"APRIL 1982 75p COMPUTER PINBALL BOUNCES BACK Brighter,brasher and with a lot more lip ENGINEER Sinclair. VIC. Tandy, Pet and Atari games programs KRIEGSPIEL DOO "


"EXPAND @VIC 135 YOUR LLY APA From FFICIA OROVED CON plus VAT. ARFON PRINTER A low cost stand alone printer which will be almost essential for your larger programs will be launched in the Spring of 1982. The power plug for this unit is already on your expanded system. EXPANDABLE TO 7 CARTRIDGES You will now be able to use up to seven cartridges to expand from your basic Vic 20. These can include RAM memory expansion up to nearly 30K of usable memory, ROM cartridges with packaged programs, user expansion cartridges, printer software, disc software, RS232 IEEE interface, line expansion firmware and many othersbesides of course all your games cartridges. ARFON EXPANSION MEMORY Immediately available from Arfon in cartridge are 3K RAM +2 sockets, 8K RAM, 16K RAM, 8K ROM, 16K ROM. Also a basic Vic simulator cartridge to allow tape and cartridge use without altering the system. VIC 20 Expansion System INTERFACES Slots have been left to allow normal use of the cassette socket, disc socket etc., which will still run normally with your expanded system The Arfon Vic 20 Expansion System is a finished metal cased unit that integrates your Vic 20 with an expansion board for up to seven cartridges and a toroidal power supply (fully enclosed) to give you sufficient power for any expansion and also to power the Arfon Vic Printer. Your Vic and its screen modulator are incorporated into the expansion system to produce one unit and there is an optional lid that covers the expansion area and allows your TV. to sit on top. Access to the various input sockets on your basic Vic 20 is not restricted while it is in the expansion unit. Stocks are available now through your own Vic Dealer. I would like to be included on your mailing list. Send to: Name Arfon Microelectronics Ltd., Address Cibyn Ind. Estate, Caernarfon, Gwynedd, N. Wales. Arfon Micro AM "


"No 6 APRIL 1982 COMPUTER GAMES VIDEO CONTENTS NEXT MONTH page 25 .....page 28 UTWIT unknown human opponents in a fantasy world adjudicated by computer. Games moderated by computer are ripe for take-off in the U.K. In May we will give you a rundown on the no-holdsbarred computer moderated games scene where you have to stay on the alert even when you're not playing! W ITH Packman games cropping up everywhere, we felt it was time we featured one ourselves. Meteor Storm, Earth Port II, Spiderman and AntiGravity Flyer also feature in an issue packed with the best games. TUST how far can you expand a Sinclair's memory? Who produces the top games software for it? What peripherals are available? Our May Hardcore section is given over to the possibilities of this unique machine. and page 46 MAILBAG ... ...........page 5 Readers comments and queries. COMPETITION ..... ......page 9 Our VIC-20 winners and a Bug confesses all. BUGS ........page 13 Mal Function declares war on all adventurers. GAMES NEWS ..........................page 14 page 14 Save Earth's inhabitants from Microchip brain transplants. VIDEO SCREENS ....... ......page 18 Out now the first games centre Packman. CHESS ........page 21 Can Chess computers take on the grandmasters and win? BRIDGE .... .. ..............page 23 PRESTEL ...... Prestel's games pages: the most popular thing on the system. ARCADE ACTION ....... .........page 26 Are you an arcade record breaker? POKER Try your hand at Poker on the Sinclair ZX81. STARFIGHTER .......page 34 Search and destroy enemy targets on your Pet in this game of deadly tactics. KRIEGSPIEL Join in a full-scale World War II battle on a TRS-80 and outmanoeuvre the computer's forces. ENGINEER Aliens have destroyed the Golden Gate bridge and it's up to you and your Atari to rebuild it. MOON-LANDER .................. page 48 Only your skill on the Atom keyboard can save the space shuttle out of fuel and plummeting towards the moon's surface. SUB-ATTACK ... Destroy convoys of enemy ships with missiles from your VIC-20 submarine which lurks deep beneath the waves. YAHTZEE. ......page 56 What lurks in the monster-infested maze? PRACTICAL PROGRAMMING ...........page 62 Learn how to handle data in your programs. AMERICAN DREAMS ....................page page 65 3 Robin Bradbeer unveils the Ultimax Commodore's latest computer. PINBALL .........page 66 You'll believe a pinball can talk! DOWN TO BASIC Moira Norrie gets to grips with character strings. ADVENTURE Delve into dungeons with the Hellfire Warrior and Keith Campbell. REVIEWS .. ......page 76 What lurks in the monster infested maze? GRAPHICS ... Garry Marshall looks at high resolution graphics on the Apple. KIT KORNER More circuit training with Keith Mott. BRAINWARE Champagne for those with agile brains. HARDCORE .page 84 Check out our guide to low cost computers. SOFTWARE GLOSSARY page 86 ...page 54 Editor Terry Pratt Assistant editor Elspeth Joiner Editorial assistant Susan Cameron Design Linda Freeman Production editor Tim Metcalfe Advertisement executives Rita Lewis, Neil Wood Advertisement assistant Louise Flockhart Publisher Tom Moloney Editorial and advertisement offices: Durrant House, 8 Herbal Hill, London ECIR 5B: Telephone Editorial 01-278 6556, Advertising 01-278 6552 ......page 70 Page 72 COMPUTER AND VIDEO GAMES POSTAL SUBSCRIPTION SERVICE By using the special Postal Subscription Service, copies of COMPUTER AND VIDEO GAMES can be mailed direct from our offices each month to any address throughout the world. All subscription applications should be sent for processing to COMPUTER AND VIDEO GAMES (Subscription Department). Competition House, Farmdon Road, Market Harborough, Leicestershire. All orders should include the appropriate remittance made payable to COMPUTER AND VIDEO GAMES. Annual subscription rates (12 issues); UK and Eire .00 Overseas surface mail .00 Airmail Europe .00 Additional service information including individual overseas airmail rates available upon request. Published and distributed by EMAP National Publications Ltd. Printed by Eden Fisher (Southend) Limited.  Computer & Video Games Limited ISSN 0261 3697. ..........page 79 Page 81 Page 83 Cover: Photograph by Linda Freeman Other Illustrations by: Elphin Lloyd-Jones, Jon Davis, Dorian Cross and Terry Rogers. NEXT ISSUE ON SALE APRIL 16th "


"zx 80/1 16K RAM PACKS 5) inc. VAT MASSIVE ADD ON MEMORY FULL SIZE KEYBOARDS WITH REPEAT KEY S.95% Sinc. VAT Why wait to pay more.m Fast delivery: Post to: Dept. CVG, Kayde Electronic Systems, 48/49 Exmouth Road, Great Yarmouth, Norfolk NR30 3DP Tel: (0493) 55253 Please send me ...... Ram Pack(s) at .95 each Please send me ....... ......... Keyboard(s) at .95 I enclose .. Name Name ....... Address......... Please add  P&P and make cheques payable to | Kayde Electronic Systems. ALL PRODUCTS ARE FULLY GUARANTEED & COME COMPLETE WITH MONEY BACK GUARANTEE 4 COMPUTER & VIDEO GAMES "


"MAILBAG Do you have any views or comments on Computer & Video Games? If so we would love to hear from you. We will also do our best to find answers to any queries you may have or solve problems you might be experiencing with your computer. Please drop us a line at: Computer & Video Games, EMAP, Durrant House, 8 Herbal Hill, London EC1R 5JB. VIVE LE SINCLAIR CHEAP AND CHEERFUL GETTING IT TAPED on Friday, February 26. calculator and the moves convert your Sinclair tape Mr Harry Cuthbert is the made are displayed on a to load, so I'm afraid you acting chairman and Mr small L.C.D. screen. You will have to either buy a David Jones the acting sec. just position your pieces Sharp games tape from a both can be contacted most accordingly. It's official supplier or have a go at Dear Mr Editing-Person, evenings after 6.30pm on name is Acetronic writing your own games. I'll start by saying what a Hartlepool 71027 or 66001. Electronic Chess and costs fab piece of material your It is hoped that anyone .95 from Ace mag is. Well thought-out, who has an interest in distributors. For a full list of dealers contact Ace at 3 interesting, colourful, witty computing will join the in places and highly club, non-owners are also Fulton Road, Wembley entertaining to the last most welcome. Park, Middlesex. Dear Sir, computer-packed page. David R. V. Jones, I am in the process of Absolutely wizard and all Hartlepool, purchasing a Sinclair ZX81 that. Cleveland and would like to know But may I outline one whether or not a cheaper slight fault ... so far you 16K RAM is available for it have only published small, Dear Sir, other than the Sinclair rather feeble IK Sinclair I want to use a Sinclair one? ZX8l games. I know the pre-recorded tape on my I would also like to know ZX8l cannot be described Sharp MZ-80K computer. As if 16K is the limit of the as the greatest personal the Sinclair ZX8I's are ZX8I's memory? If not, I'd computer but give it some Dear Sir, simple machines I thought like some details please. I would be grateful if you credit, please. it would accept it, but it I own a JVC T.V. cassette If it's not too much for could help me with some wouldn't load. radio set and could you tell information. All the your megabytic brain to Could you tell me if it is me if I can use it in manage, could you print computer chess games possible to load these conjunction with the ZX81 an exciting, highly advertised seem to work on cassettes on to my machine for the T.V. and cassette interesting and graphically boards and pieces are and what I should do to facilities? I would also like stunning 16K Sinclair game supplied. make it work? to know if the ZX8l can which will be a credit to Have you any knowledge I look forward to the next have sound facilities. all ZX8l owners and will of a straightforward chess issue of your magazine and V. Buchanan prove to other more computer i.e. to cater for hope you don't forget the Dollar, advanced computer owners the persons like myself Sharp MZ-80K Scotland that it's more than a child's who already own a chess P. Alsen, board and pieces. toy. Stockton Lane, Editor's reply: There are a Ronald Whiteside, Everyone knocks the York couple of firms who supply ZX81 but I think other Lisnasharragh, 16K RAM packs for the Editor's reply: First the Belfast Sinclair ZX81 which cost computer manufacturers good news Mr Alsen, we should follow Sinclair's less than Sinclair's own Editor's reply: The only will continue to feature the example and produce a version. These are: Audio Sharp MZ-80K in the computerised chess game basic, low-cost and Computers of on the market which you magazine. Now the bad compact machine which Southend-on-Sea which can be expanded to be news. You can only use can use your own chess costs . Byg Byte of cassettes which contain board and pieces with is more powerful through the Petersfield, Hampshire made by Ace of Wembley. programs specially written addition of plug-ons, like which sells one for .95. memories, keyboards, The actual computer looks for the Sharp with an Expansion boards are sound systems etc. MZ-BOK. There is no way to very like a pocket available for the ZX81 right Peter Townend up to 128K. Audio Walmer, Computers is the firm selling that, and smaller Kent. memory boards: 32K, ; 64K, ; 128K, . I'm afraid that your JVC is not one of the cassette recorders Sinclair Research recommends. I suggest you Dear Sir, write to Sinclair and they We would be most obliged will give you a full list of ZX81 compatible cassette if you will let your readers recorders. know that a computer club Alternatively, you could has been started in the Hartlepool area, via your wait until we publish our next issue (May) when we Mailbag pages. The first meeting of the will be featuring the ZX81 club was held at The in our Hardcore pages Welfare Hall for the Blind, giving details of Avenue Road, Hartlepool peripherals available. COMPUTER & VIDEO GAMES 5 CLUBBING TOGETHER "


"ZX 80/81 HARDWARE/SOFTWARE ZX KEYBOARD Now with Repeat Key A full size keyboard for the 80/81. The keyboard has all the 80/81 functions on the keys, and will greatly increase your programming speed. It is fitted with push type keys as in larger computers. The keyboard has been specially designed for the Sinclair computer and is supplied readybuilt. It also has facilities for 4 extra buttons which could be used for on/off switch, reset, etc. .95 222222222 @eeeee2120 ele 4K GRAPHICS ROM The dk Graphic module is our latest ZX81 accessory. This module, unlike most other accessories fits neatly inside your computer under the keyboard. The module comes ready built, fully tested and complete with a 4K graphic ROM. This will give you 448 extra pre-programmed graphics, your normal graphic set contains 64. This means that you now have 512 graphics and with there inverse 1024. This now turns the 81 into a very powerful computer, with a graphic set rarely found on larger more expensive machines. In the ROM are lower case letters, bombs, bullets, rockets, tanks, a complete set of invaders graphics and that only accounts for about 50 of them, there are still about 400 left (that may give you an idea as to the scope of the new ROM). However, the module does not finish there; it also has a spare holder on the board which will accept a further 4K of ROM/RAM. IT NEEDS NO EXTRA POWER AND WORKS FROM YOUR NORMAL POWER SUPPLY. .95 RAM 80/81 16K RAM Massive add-on memory for 80/81. 16K KIT-A-KIT VERSION of a 16K Ram. Full instructions included. All memory expansions plug into the user port at the rear of the computer. 16K RAM .95 16K KIT .95 2K & 4K RAM Static Ram memory expansion for the 80/81. They both work with onboard Ram i.e. 4K plus onboard = 5K. This is the cheapest small memory expansion available anywhere. 2K RAM .95.4K RAM .95 16K 81 SOFTWARE As seen at the ZX Microfair. DEFLEX This totally new and very addictive game, which was highly acclaimed at the Microfair, uses fast moving graphics to provide a challenge requiring not only quick reaction, but also clever thinking. One and two player versions on same cassette. .95 3D/3D LABYRINTH You have all seen 3D Labyrinth games, but this goes one stage beyond; you must manoeuvre within a cubic maze and contend with corridors which may go left/right/up/down. Full size 3D graphical representation. .95. CENTIPEDE. This is the first implementation of the popular arcade game on any micro anywhere. Never mind your invaders, etc., this is positively shining, the speed at which this runs makes ZX invaders look like a game of simple snap. .95. Please add  p&p for all hardware, Software p&p free. Specify ZX80/81 on order. ALL OUR PRODUCTS ARE COVERED BY A MONEY BACK GUARANTEE dK'tronics 23 Sussex Road, Gorlestone, Great Yarmouth, Norfolk. Telephone: Yarmouth (0493) 602453 6 COMPUTER & VIDEO GAMES "


"THE SEARCH FOR SPEED SYSTEMS ANALYSIS | looking for the fault. My experts the adaptor, which far it is possible to enlarge friend's father, who deals is expected to cost between the system capacity and in computers, was also  and , is only capability. If the ZX81 puzzled by this. I would be worthwhile if you have possibilities are limited very pleased if you could relatively small amounts of without major surgery! Dear Sir, assist me to solve the data to store if you can't then I would seriously Congratulations for a new, problem. afford the price of a have to consider another excellent and very different E. Bryant, Commodore recorder. system. I was horrified to magazine. The series on Haxby. Commodore's expert did see no less than 49 Sinclair writing Adventure type York. say that the quality of ZX80/81's for sale on the games is superb and material stored using this transaction page of another Round the Horn was the Paul Jay replies: There is, adaptor would not be as magazine. Could it be that best program I've ever seen in fact, no fault in the good as a Commodore other ZX owners are losing published for TRS-80. Nibblers program. The compatible because normal heart? Help!!! I know you're more of a trouble is that you have got recorders record audio Who makes the 64K RAM software magazine, but as an old PET. signals rather than NRZI slot-in mentioned in your yours is the only mag I buy Many of the memory signals the method used January issue? regularly (grovel, grovel) I Locati locations have been to record computer signals. Chris Wilkes would like to ask a changed since the original Commodore itself does Harefield, hardware question; I know machine came out. The not make an adaptor to Middlesex. the clock in the TRS-80 can location that has been convert a normal recorder be speeded up, but I'm not changed in this particular for use with the VIC-20. sure how and what program is 151. When the Editor's reply: You can components have to be machine looks at this part enlarge the ZX81 up to 128K bought. Could you tell me of memory, it can tell if a memory using a range of how or suggest where a kit key is being pressed down. expansion boards. Audio can be bought? I want it All you have to do to make Computers is the firm to switchable between old the game work is to contact at 87 Bournemouth and new speeds for change the 151 which Park Road, purpose of tape transfer. appears twice, to a 515. Southend-on-Sea. My set-up is TRS-80 Model This will also be necessary Dear Sir, 1 Level 11 16K with Here is a list of prices: if you want other PET As the proud owner of a cassette and Aculab. 16K  programs to run on old ZX81, I would greatly like C. Bennett 32K  machines. For example to expand it in all Bamkin-of-Craigs, 64K  Dragon Druggin'. directions. However, the Dumfries. 128K $123 proliferation of add-ons, Editor's reply: According to software and books too Audio Computers will be Martin Soble of Tandy numerous to mention have happy to give you further Corporation's reduced me to gibbering details of goods available merchandising department, lunacy! for the ZX81 if you get in it is possible to increase I would like to know how I touch with them. the speed of the Dear Sir, microprocessor in your I have recently acquired a computer itself but he does VIC-20 and after hearing not recommend doing so. from a friend about a He told Computer and connection to fit a normal Video Games that a couple tape recorder to it. I of small dealers sell kits to decided not to buy the  carry this out, but he plus, special tape recorder. likened it to doing a \"hot i asked in the shop my rod\" conversion on a car. It friend told me about and goes faster but wears it out they said they were more quickly. expecting some in soon. So if you want your Impatiently I asked at TRS-80 to last, take Martin another shop and they Soble's advice, you will be didn't know anything about better off in the long run. it. Is the connection made by Commodore or by another firm? Nadeem Farugue Newton-with-Scales, Lancashire. CONNECTIONS NIBBLERS NIGGLE... Dear Sir, Having tried out the Nibblers program in the first edition of Computer and Video Games, I found that I could not fire missiles or drop bombs on the Nibblers. I am new to computers and so would not know where to start Editor's reply: A firm called Stack of Liverpool is in the process of bringing out an adaptor designed to link up a normal cassette recorder with the VIC-20. but has not yet brought it out. But according to one of Commodore Business Machine's technical "


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Telephone us with your name and address and we will add your name to our computer mailing list. T.V. GAME CARTRIDGES HAND-HELD GAMES EARTH INVADERS We specialise in the whole range of TV games and sell cartridges for the following games ATARI MATTEL ACETRONIC PHILIPS DATABASE ROWTRON INTERTON YELENG Let us know if you own any of these games and we will let you have details of the range of cartridges available Attention INTERTON & ACETRONIC owners we have over 75 assorted used cartridges in stock all with 1 year guarantee SPECIAL OFFER (8.95 each We also have a number of secondhand games and cartridges These inden we tweed of creature that nown toman They cannot be killed by traditional methods they must be buried The conducted in a more whereas of aliens the home troops The only way of eliminating them by doing holes and buying them NOW  OFF R.R.P. .95 NOW .95 inc. 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VAT ZR THE AFFORDABLE ANSWER RADOFIN TELETEXT CALL / LESS THAN V PRICE worden voor SALE PRICE .50 NOW  OFF BACKGAMMON COMPUTER 12 THE PRICE OF COMPARABLE MACHINES The Post Office certified telephone answering machine Sorry darling, I will be late home-Love John The Call Jotter I brings the affordable answer at the amaring price of 59 for 99 for the Call Jotter 2 with built-in remote recall facilities These amazing telephone answering machines are Post Office certified and guaranteed for one year. They make a thoughtful gift for home or business use Call Jotter 3 illustrated NOW .00 inc VAT WINTAPE 19 ADD-ON ADAPTOR WAS 199ine VAT SALE PRICE  Now .95 inc VAT in VAT Silica Shop FOR FREE BROCHURES -TEL: 01-301 1111 SILICA BHOP CREDIT FACILITIES Full crea t es available 12 24 36 months at com SILICA SHOP LIMITED CVG0482 1.4 The Mews, Hatherley Road, Sidcup. Kent DA14 4DX Telephone 01-301 1111 or 01-309 1111 8 COMPUTER & VIDEO GAMES "


"ITIONCOMPETITIONCOM THE PICK OF OUR PUZZLERS Confessions of a  The octagon puzzle which featured on the cover of our first issue, certainly set your greymatter alight. Over 700 entries of programs to solve the puzzle by computer, deluged our office and caught us quite unawares. Whittling down all the entries was a long and difficult task for our judges but they have finally come up with the three best entries. To give everybody a fair chance we laid down a set of criteria for the judges to use as a guideline in making their comments. Entrants could score a possible total of 45 points for the programs submitted, but no-one managed a 100% score. The most important aspects of the judging were on the standard of programming. Exactly how concise the programming was and whether it contained unnecessary frills into the entry. Another important factor in judging was the speed each program took to find the solution. Highest marks went to those whose programs found the solution quickest. Further points were awarded if it proved there was only one solution. The three to emerge as winners are Gorden Bennett of Hampshire, Adrian Womack of Doncaster, and Christopher Holt of Gravesend. Gordon achieved the highest score of 43, Adrian got a close 41 and several reached the 40 mark. Our judges finally selected Christopher Holt's entry as the third winner because it was the best presented of the three tying programs. Congratulations to the three final winners and our commiserations go to the other unlucky hundreds who entered. The winning program by Gordon was written for a Microtan 65 computer and earned high points because of its simplicity of execution and accuracy in programming. With his program listing he submitted documentation but none of it was in-depth details about converting symbols to numbers or letters. You also didn't have to sit and wait for a long time for the program to do something, which was a common complaint. Another interesting feature of this program was that instructions were explained in the program itself, making it easy to use. The solution was found in one minute 44 seconds. The other two winning programs were of an equally good standard of programming finding the solutions quickly. But they fell down on other points, particularly presentation. They were written for a Sinclair ZX81 and an Acorn Atom. Three VIC computers will be winging their way towards the winners as soon as possible. We wish the winners hours of happy programming and also offer our thanks to the many judges for their time and effort. Just in case any of you out there weren't appreciating the work which we Bugs are putting in behind the scenes here, I've persuaded the editor to give me my own column to explain. Changing Hearts in the March issue was one of our biggest successes-made all the more so by the fact that many readers managed to enter it first time. The listing itself was error-free but two all-important commas went missing from the accompanying write-up. Line 40 in the write up should read: G$ = \"ABDE,ABC,,BCEF, ADG.,BDEFHCFI,DEGH,GHIEFHI,\" Alien Hunt in the February issue also caused some problems for readers whose Acorn Atom did not have sufficient of the necessary memory to run it. Unfortunately author John Kirk was all too quick to their rescue, suggesting that they remove instructions subroutine in line 1 and lines 32000 to 32111. T. Hitch was put to work at the printers to give Dogfight fans a little extra workout on the Apple in the February issue. He transposed lines 1160 to 1190 out of position, which itself would have been easily righted, but then he cunningly continued with: ITS\";M(2);\"MISSILES\" which belongs to line 1309. Screaming Foul-up did the printing run for the March issue and pulled seven lines out of the Air Attack listing. The missing lines are: 2050 LP=O:K=0:GOTO 100 2100 FOR ZQ=1 TO 21 2105 ZX=ZQ*41+X+1: POKE ZX, 28 2110 BN EPEEK (ZX +41): IFBN = 32 THEN 2120 2115 GOTO 2200 2120 POKE ZX, 32: NEXT ZQ BRAINWARE ANSWERS The answer to our March Mind DUALDISK DRIVE Routines problem is that there E E ON are 34 prime numbers. The highSHIFT T O P est is 95731 and the lowest is c T SURROUND 13497. The total of the 34 prime RUGBY ST numbers is 1842502. A A05F The correct solution to last month's Nevera Crossword is BLACKANDWHITE printed right and the winners BK ON names will be published in next L E A S SWORD month's issue. ENVELOPED For more puzzles to tax your ET o COVER mind turn to page 83 where you NEO will find this month's problems. NATURALWINGER 2130 GOTO 100us Mal "


"it's here at last! www Upgrade your atom with our NEW3 new low cost disc pack only  plus VAT www 40 -track single-sided 5%\"disc drive -power supply to run both the disc pack and a fully expanded Atom disc controller card with 4K DOS ROM 3k bytes of static RAM -64-way Euro-connector plug and cable full operating instructions and manual The disc controller is based on the Intel 8271 chip. This highly itelligent device minimises the amount of control software and memory requirement and so allows phenomenal high speed operation. Both soft and hardware has been vigorously tested and proved very, very reliable. You will need an Atom with bus buffers and indirect edge connectors. The mail order price is  including VAT post, packing and insurance, the price at your Atom dealer , If you do not have a dealer near you just write to us at the address below, or credit card holders can ring Cambridge (0223) 245200 and order directly Disc pack for the atom Acorn Computers Ltd., VACORN Fulbourne Road, COMPUTER Cherry Hinton, CAMBRIDGE The disk operating system (DOS) decodes the following commands used to control the storage of files on disk: CAT catalogue files on disk LOAD load image of memory contents as file *SAVE save image of memory contents as file \"DELETE delete file from disk *SPOOL store all printer characters on disk * EXEC read characters from disk as if from keyboard The DOS also replaces the cassette operating system vectors as used by BASIC to allow the use of the following commands in Atom BASIC: LOAD load BASIC program from disk SAVE save BASIC program to disk FOUT open file for output FIN open file for input SHUT close file EXT find extent of file PRT find value of pointer into file PUT put number to file BPUT put byte to file SPUT put string to file GET get number from file BGET get byte from file SGET get string from file These commands provide full random access of up to 5 disk files simultaneously, Use Your Atom forPlanning .... Projecting .... Writing .... Estimating ... Scheduling ....Calculating .... Recalculating .... Erasing .... Revising .... Critical Path Analysis.... With ATOMCALC only .10 inc. VAT What is it? Atomcalc is supplied as a plug-in 4k ROM with an all-purpose planning and modelling program. It is so easy to use. If you can use a calculator you can use Atomcalc. No programming skill needed. The ROM creates an enormous grid of columns and rows like a ledger. All you do is to enter the headings and formula once and Atomcalc does the rest. Supplied with a very detailed 30pp user handbook. What will it do? Atomcalc can cope with anything from a household budget to company accounts. You set up a series of automatic calculating functions like totalling or percentages. Then fill in the columns with your figures and the program produces the answers. If you want to change one figure in the calculation it immediately changes the relationship of all the other figures involved. So, for example, you can see what effect on profit a 5% increase in sales might have or a 10% increase in production, or a 3% drop in transport. And do not forget you can print them out on an optional printer or store them on tape. How Can I Buy One? Go to your Atom Dealer, or if there are none in your area just send a cheque for .10 (incl. VAT and P & P) to the address below. Credit Card holders can ring Cambridge (0223) 316039 and order direct. Dept. 6 Acornsoft Ltd, 4a Market Hill, CAMBRIDGE. ACORNSEFT Brand new colour board www NOW YOUR LIFE CAN  BE MORE COLOURFUL! Im The board fits inside the Atom and generates colour output suitable for all makes of monitors and TV's. Two colour palettes can be achieved Red, Yellow, Green, Blue and White, Cyan, Magenta, Orange. In text modes this provides green on blue or orange on black displays. Three outputs are provided:Red, Green, Blue drives at TTL levels with a composite sync, the polarity of which may be link selected. A lv composite video in monochrome only. A PAL encoded signal on Channel 36 suitable for feeding into the aerial socket on a domestic television You can fit the board yourself using a fine soldering iron or your dealer will fit it for you. The board can be used in a minimum Atom with the existing power supply, or if used in a maximum Atom a 5V exernally regulated supply will be necessary. Available from all Acorn Dealers or direct from Acorn at .24 inc VAT and p+p. Credit card holders can ring (0223) 245200 and place their orders direct. Acorn Computers ACORN Fulbourne Road, COMPUTER Cherry Hinton, Cambridge 10 COMPUTER & VIDEO GAMES "


"ACORN COMPUTER ACORN DEALERS For all the latest Atom hardware and software contact the dealers below Ltd., Personal Computers, 20 Wellington Square, AYR (0292) 285082 Broadway Electronics The Broadway BEDFORD (0234) 213639 Microcentre Ltd., Commercial House, 19 Station Road, BOGNOR REGIS (0243) 82779/828108 Eltec Services Ltd., 231 Manningham Lane, BRADFORD (0274) 491372 Gamer, 24 Gloucester Road, BRIGHTON (0273) 698424 Cambridge Computer Store, 1 Emmanuel Street, CAMBRIDGE (0223) 65334 M. D. Wright Data Services Ltd., 13 Vernon Place, CANTERBURY (0227) 69090 Cardiff Micro Centre, 46 Charles Street, CARDIFF (0222) 373072 Computer Shack, 14 Pittville Street, CHELTENHAM (0242) 584343 Vixon Computer Systems, 49 Grimsby Road, CLEETHORPES (0472) 58561 Datron Micro Centre, Duckworth Square, DERBY (0332) 380085 Lendac Data Systems Ltd., 8 Dawson Street, DUBLIN (0001) 372052 Cardigan Electronics, Chancery Lane, CARDIGAN (0239) 614483 Microage, 135 Hale Lane, EDGWARE 959 7119 Silicon Centre, 21 Comely Bank Road, EDINBURGH (031) 332 5277 Northern Computers, Churchfield Road, Frodsham, Nr WARRINGTON (0928) 35110 H.C.C.S., 541 Durham Road, Low Fell, GATESHEAD (0632) 821924 P. J. Equipments Ltd., 3 Bridge Street, GUILDFORD (0483) 504801 D. A. Computers, 184 London Road, LEICESTER (0533) 549407 Group 70, 208 Maybank Road, South Woodford, LONDON E18 505 7724 The Centre of Sound, 120 Notting Hill Gate, LONDON W11 727 0511 Euro-Calc 55/56 High Holborn, LONDON WC1 405 3113 N.S.C. Computing Shops, 29 Hanging Ditch, MANCHESTER (061) 832 2269 Q-Tek Systems Ltd., 2 Daltry Close, Old Town, STEVENAGE (0438) 65385 Arden Personal Computers, 166 Park Road, PETERBOROUGH (0733) 47767 R.D.S. Electrical (Portsmouth) Ltd., 157/161 Kingston Road, PORTSMOUTH (0705) 812478 Computers For All, Romford Computer Shop 72 North Street, ROMFORD (0708) 752862 Datron Micro Centre, 2 Abbydale, SHEFFIELD (0742) 585490 3D Computers, 230 Tolworth Rise South, SURBITON 337 4317 Computer Plus, 47 Queens Road, WATFORD (0923) 33927 Datex Micros, 193 Tarring Road, WORTHING (0903) 39290 ACORN COMPUTER COMPUTER & VIDEO GAMES 11 "


"SPACE FIGHTER (6K +3Kgr) Super High-speed \"Defender game. 5 types of intelligent aliens, Repeating laser cannon, smart bombs, hi-score, rankings, bonus pts. 6 skill levels Exciting sound effects .95 COWBOY SHOOT-OUT (12K) Full feature, two-player, arcade shooting game. Cactus plants, moving chuck wagons, animated cowboys. Superb graphics & sound 25.96 WARLORDS (12K). Another hi-speed arcade game with the medieval touch. Defend your castle & destroy your opponent's. Play against computer or other player. Exciting graphics. .95 MUNCHYMAN (6K) Outrun the munchers for puckmen), Eat your way to a high points score and confrontation with the SUPER MUNCHERSIE .95 ATOMSTORE (12K+) General purpose 'database' filing & printing pro gram. User-defined fields. Variable field & record length. Highly economical. Use for names & ad dresses, product lists, price list -any data file. File search, printing & saving options. .95 ACORN ATOM CHESS (12) Improved graphics, plays back or white, mid-game level changes, look ahead up to 8 moves, often Sive, normal & defensive play. 10 sub-levels, casil ing. \"En passant\" by player. Rejects illegal moves. Take back moves & action replay with take-over, Set up problem games. ONLY .95 ASTROBIRDS (12K) New version of this incredible GALAXIAN type game. Fantastic sound effects! Screaming missiles & Swooping bird-men. NOW DOUBLE SPEED OPTION. The best game on the market. .96 INVADER FORCE (12) Terrific version of 'Space Invaders 4 types of invaders, mother ship. great sound, hi-score, 6 skill levels. .96 LUNAR LANDER (12) Superb version of this arcade game. incl. long & short range scan. limited fuel supply. .96 3D ASTEROIDS 16K + 2Kgn Steer through the rolling, hurthing asteroids. Excellent real life graphics MARTIANS (12K+VIA) Use your force field to stop them landing. Beware the imposters. Needs quick reactions. CONSTELLATION 112K+FILPt) Turn your ATOM into a telescope. View the stars from any point in the N.Hemisphere. 448 stars in 50 constellations instantly plotted against the night sky. Zoom in & out, raise & lower angle, rotate clockwise & anti-clockwise. .95 EXTRA MEMORY — Low power chips as recommended by Acorn 2 x 2114L .25 WRITTEN ANY PROGRAMS? WE PAY 20% ROYALTIES! ***SPECIAL OFFER Deduct  per cassette when ordering 2 or more.\" Please add 55p/order P&P + VAI @ 15% Send Sae for FULL CATALOGUE PROGRAM POWER 5. Wensley Road, Leeds LS7 2LX. Tel. (0532) 683186, Acorn Atom SPECIAL ANNOUNCEMENT ATOM ADVENTURE ALL THE EXCITEMENT, INTRIGUE AND FRUSTRATION OF A MAIN-FRAME ADVENTURE! CRAMMED INTO A 12K ATOM Explore the tortuous forests, dark caverns & castle dungeons Beware the maze of twisting tunnels and the desert wastelands Outwit the predators. Rescue the PRINCESS and carry off the treasures PROGRAMMER'S TOOL-BOX A packed 4K EPROM (fits Utility Socket) containing: 1200 BAUD CASSETTE OPERATING SYSTEM Visible Load and Save routine PLUS TRACEX) controlled execution, line no display  STEP single step execution FIND any string of chars, in program VAR list variables LVAR print variables AUTO XY automatic line numbering (any start, any step RENUMBER X,Y any start, any step DELETE X to Y any range to line nos (\"VIA chip required) HEX Hex and ASCII Dump IHEX Hex Dump in Instruction format PLUS Additional BASIC statements READ,DATA & RESTORE KEY X scans keyboard-input to variable INKEY $X scans keyboard-input to string variable IF... THEN... ELSE WHILE ENDWHILE CURSOR X,Y -position cursor as required ON ERROR BEEP XY sound a note-any duration, any pitch ZERO zeroes all basic variables POP close out sub-routine STOP Useful debugging instruction Suitable for any memory size. Greatly enhances the Atom's existing facilities. Real Value at .50+VAT & 25p P&P 5, Wensley Road, Leeds LS7 2LX Tel. (0532) 683186 PROGRAM Send S.A.E. for details & full catalogue. VISA POWER (State Atom) Great skill & imagination are required to play this excellent game & you may still never exhaust all the possibilities. By devising methods of condensing messages, the author has been able to include many features which would otherwise be available only on much larger computers Start your Adventure now .95 (+ VAT & 55p P&P) from PROGRAM POWER 5. Wensley Road, Leeds LS7 2LX. (Tel. 0532 683186) 12 COMPUTER & VIDEO GAMES "


"MAL FUNCTION SNAG JNR SCREAMING FOUL UP T. HITCH HELP! SOMEONE GIVE HIM SOMETHING TO APPEASE HIM! 000 * ALERT* TROLL LOOSE CIRCUITS SO000 THAT'S IT!IM FED UP WITH THESE ADVENTURE CREATURES RAMPAGING ABOUT IN OUR MACHINE..... PRISE! 3 ood logo HMM! A 2114 JUST WHAT I NEED FOR MY ACORN ATOM A PROTEST MEETING WILL BE HELD IN THE MEMORY SECTION BE THERE! .. SO WE ARE AGREED THEN, WE WILL NOT STAND BY WN ILE WIZARDS, GOBLINS ADVENTURERS... .. AND OTHER HORRORS USE OUR MICRO AS A PLAYGROUND FOR THEIR PERVERSE FANTASIES. THEREFORE.. NO ENTRY RANDOM ACCESS ONLY MUB BUB! MEETING ANTI ADVENTURERS ASSOCIATION **::: HEAR! HE 1 ACCEPT! AWISE CHOICE IF I MAY SAY.. you! S PROPOSE WE ELECT SOMEONE TO TELL THE LEADER OF THAT MOB TO PULL OUT THEIR PLUGS AND GET OUT !! YOURE ELECTED! GOOD OL MALFUNCTION SNIGGER) GO GET EM!' SO! IF YOU COULD SEE YOUR WAY CLEAR TO KEEPING THE NOISE DOWN A BIT. "


"NEW PRODUCTS NEW PRODUCTS NEW PRODUCTSN KEEP THE ASSASSIN'S KNIFE AT BAY DEADLY BLADES IN THE NIGHT Deadly blades flash as you relive DUEL IN THE DARK Being the President of a small the duelling days of the eighstate can cause you a few probteenth century in a darkened lems. Often your country is on dungeon. single player mode the computer the brink of civil war or revoluYou must kill your opponent takes the role of a bear seeking tion. after searching him out in Duel in you out. But as the head of the state the Dark, a game for one or two During play you discover your job is to ensure the smooth players. information about the dungeon's running of political life and aim to The screen is divided into a layout making notes of the achieve prosperity for your rectangle of squares which forms location of windows, doors, people. your battleground. It represents objects and walls. That's just what you have to a dungeon which has two win. When the crunch comes you do in Dictator, an adventure dows. But you can't see anything have three methods of doing game for the ZX81 in 16K. because it's dark outside none away with your opponent. Either The object is to prevent your too helpful. throw the knife at him, stab him people revolting. At your disThe only good thing is that with your dagger or grab him and posal are the army and secret DICTATOR your opponent faces the same grapple him down. police who you can use to your handicap — he can't see you Duel in the Dark costs .93 advantage if the threat of a coup to maintain a secure economy. If either. from Bexhill based Molimerx and arises. you fail unrest could mean your Objects litter the dungeon is designed to run on a TRS-80 You must be vigilant because ultimate downfall. which are hazardous but also level II. spies may infiltrate your close An eight page instruction give you clues to your oppoknit party. Assassination booklet is supplied with the casnent's whereabouts. attempts are regular events. sette giving full information. Both of you are given a dagger To keep the people happy you A copy of Dictator can be and a knife as weapons in the have to make the right decisions bought from Bug-Byte for . two player version. If it's in GALACTIC WAR FLEET SPACE FIGHTER OOOO boo. HERE'S THE LATEST IN BRAINWARE Alone in deepest, darkest space you come face to face with a horribly beweaponed and decidedly unfriendly galactic war fleet. With the stars your only company your mission is to find and destroy five enemy fighter craft. They patrol different sectors of the sky and when they are within range you line them up in your sights and blast them. Your armament consists of laser guns A band of roving aliens are scanwhich instantly reduce the ADVENTURE C ning the universe for humanoids enemy ship to fragments of with the decidedly unfriendly aim space dust. of taking out their brains and through space into all sorts of The fighters are equipped with replacing them with microchips. hazards. You explore computer In the last issue of Computer & missiles and can return rapid fire What do you mean you know rooms, an android pleasure room, Video Games, the cassettes for at your ship so you have to avoid someone they found already!? penetrate force shields and fend Tank Raid, Six keys of Tangrin destruction. Your task is to defend your off laser guns. and Tanlan Adventure were Space Fighter is a re-vamped ship from the aliens and escape Adventure C makes full use of attributed to the Tangerine User version of the original game and the gravity beam which has the Sinclair ZX81's 16K memory Group (TUG). now runs on a TRS-80 Colour sucked your ship into the alien packing in as much as possible. In fact, these games are supComputer. Molimerx, the supcruiser's flight path. Artic Computing in Hull is the plied and distributed for the Mic plier, claims the game lends itself It is during a reconnaissance supplier and will sell it for . rotan 65 computer by Microtanic to colour graphics which make it mission that your android Fred Artic Computing is establishSoftware of Dulwich in London. more realistic. spots the alien ship and warns ing a series of adventure games Tanlan Adventure and Tank You need joysticks and 16K you of their intentions. which are written in-house in Raid run in 16K and The Six Keys memory as well as .06 to get Your adventure leads you machine code for speed. of Tangrin in 8K the game up and running. MICROTANIC'S which instantly reduce the TAPE TRIO "


"JEW PRODUCTS NEW PRODUCTS NEW PRODUCTS NEI NEWS TGIVING THE CUBE A NEW DIMENSION That most frustrating of puzzles Rubik's Cube is maintaining its RUBIK'S CUBE popularity with the arrival of two computerised solutions. cube has a four-by-four grid so A game to help you solve your there are even more combinacube on your screen without any tions to puzzle over. of the thumb twiddling is now To cope with the complexity available for the Texas Instruthe program uses special comments 99/4A computer. mands allowing up to 30 moves Sticking to the original conto be stored for scrambling or cept dreamed up by Rubik the unscrambling whenever the user game allows the player to simuwishes. late every possible rotation in Work Force of Luton take the order to solve the Cube. If you blame for any extra frustration find it all too mind-blowing you this might cause you. And if you can always save it on tape and part with  you can take on the pick up where you left off later Quadcube. after giving your addled brain a rest. Another feature of the simulation enables the player to spin the cube to see the reverse sides. But for those of you who can solve the Cube in 30 seconds flat, there's always the Quadcube. The sinister sounding QuadCASSETTE TWO A BUMPER PACKAGE OF 10 But for those of you who can GAME ON THE A bumper package of games to BACKGAMMON jolt your brain into action comes in the shape of this tape for the The joys and frustrations of If it's an illegal move the comZX81. Backgammon come to the small puter will tell you so. There are 10 games; Othello, screen with this computerised A special feature of the game Awari, Laser Bases, Word version. is a tumbling dice effect repMastermind, Rectangles, Crash. The game, beloved by the resented by a graphics demonRoulette, Pontoon, Penny Shoot gambling fraternity, is well suited stration. A full instruction sheet and Gun Command. to computerisation and makes a and rules of Backgammon come Each of the games on the tape capable opponent. with the program, which is writis explained in the accompanying There are six strategies to ten for the Nascom and costs leaflet plus loading instructions. Choose from and the computer .95 from Future Software of You'll need a 16K machine to run soon latches on to your attempts Chelmsford. the games tape which is simply to defeat it. For the uninitiated, Backgamcalled Cassette Two. The makers, Futura Software, mon is a simple race game, with It's the second cartridge in claim the game has a fast two players trying to be first to this range produced by Michael response time as well as a high move into the home section and Orwin of Willesden, London, and standard of play. When you make off the board. But counters left sells for . Copies can be a move the computer brain alone can be returned to the obtained from him by mail order. automatically checks if it is valid. start by an alert opponent. MEETING METEORS HEAD-ON Cosmic Zap is one of the latest in of the deadly asteroids. COSMIC ZAP a batch of Sharpsoft games for Another feature of the game is the Sharp MZ80-K computer. the mother ship, which makes an You are fighting against time facility for the five top scorers to appearance after 10 minutes of 10 minutes to be precise be put into the memory. the game. The mother ship could and your job is to survive an The asteroids can be deceivbe your saviour because it has a asteroid storm while destroying ingly menacing. Without warning device which your ship can use aliens at the same time. the aliens you think you are for docking purposes. Points are scored for each ramming, fly into your flight path C osmic Zap is on sale from object you destroy and there is a and on face transforms into one London based Sharpsoft for .85. "


"THE VIC NEEDS VIC REVEALED THE DEFINITIVE REFERENCE BOOK ON THE VIC SYSTEM FROM NICK HAMPSHIRE Now available. Price .00 from Commodore dealers and bookshops. Nick Hampshire Publications, P.O. Box 13, Lysander Road, Yeovil, Somerset. 16 COMPUTER & VIDEO GAMES "


"NEW PRODUCTS NEW PRODUCTS NEW PRODUCTS GAMES NEWS VICMEN GHOST OF A CHANCE OUTPOST WTTTA CRUDS! A HARD RAIN'S GONNA FALL VIC software is at last filtering You are only given three lives through to owners of the long so you must be careful manoeuvawaited machine and Bug Byteering your glooper along the has leapt in quickly with some paths of the maze. If you run into games. a ghost, your life is lost as he Kicking off the range is Vicgobbles you up. man, the VIC version of the popuWhen you eat one of the lar arcade game Pacman. Bug ghosts a pair of flashing eyes Byte says this game is a very darts back to the centre of the good copy of the original with screen. You can use either joylots of little mazemen and a sticks or keyboard controls to \"glooper\" who runs around the run the game, depending on your maze devouring dots as he goes. own preference. Fruits appear in the maze The screen has to be cleared when you amass a certain of all the dots to earn a new one The Kamicosmic Cruds are one of a meteor shield. Your square number of points and large flashand a new fruit to consume. the most hostile species to be shaped ship has weak spots, paring dots cause the mazemen and The colourful VIC is well suited found in space-like Vogons ticularly vunerable to enemy fire. glooper to change colour. Some to reproducing a good replica of except without any literary pre. Two hits on the same side of times the mazemen are in a conthis absorbing and addictive tensions. the ship spell death. One hit sumable state and it's then that game. You only have two types of prevents the propulsion unit they run away from the Vicman runs on the unexweapons to call on to defend rotating the ship to that position. glooper ... but be careful, they panded VIC and costs  from yourself when you come across If you overwork the unit it will may suddenly turn tail and turn in Bug Byte of Liverpool. them in Outpost. overheat and stop working. pursuit of you. They are a propulsion unit and Outpost is difficult to operate because you have to use eight keys to control the action. But once you have mastered the A deadly rain of missiles is falling MISSILE BASE space bar. The enemy's fire will technique it proves a demanding on your cities. You must save destroy your bases if you do not game. them from destruction. stop them in mid-flight. It runs on an Apple Il in 48K The Acorn Atom version of the The cross will move to the Missile Base forms the maior and is available from Richmond popular arcade game Missile appropriate spot that the degame on Games Pack 11 accombased SBD Software for .95. Command is included on the pressed key represents. As you panying a version of snooker and latest Acornsoft package. can guess it takes a while to traditional dominoes. Available You get three ground bases to work out and memorise exactly from Acornsoft of Cambridge for form your defence sites. Aim where the cross will land up. .50. your fire at a marker cross which you can also select the top or you position on the screen using bottom area of the screen as any key on the keyboard. Each your target area and can swap letter and number key has a locathem at will by pressing the THE BIBLE tion mapped on to the marker cross corresponding to In the beginning was the word a memory site. and the word was \"oops ...\" That is, the word according to The Bible of Automata Cartography in its new game. Sticking to the firm's humorous line in games tapes. The Bible takes you through 10 games programs on a journey along the well trodden path of the Old Testament. It kicks off with a game entitled Genesis, and then moves on to Adam and Eve. Later on in the tape you can relive Moses' experience on Mount Sinai and deliver the 10. Copies are obtainable from Portsmouth based Automata and costs .00. It runs on a Sinclair ZX81 in 1K WORD WAS OOPS ... COMPUTER & VIDEO GAMES 17 "


"TVGAMES CENTRES TVGAMES CENTRES TVGAMES VIDEOSCREEN BEST SELLERS THE MONSTER FROM OUTER SPACE SAVE THIS POOR SOUL'S NECK A bright red monster from space is still tormenting Philips G7000 owners up and down the country, causing widespread frustration and havoc. Running riot on video screens is Space Monster, which was recently topping the sales figures for Philips. The game is a space invader spin-off, but with additions which demand some quite different tactics from the hide behind. Whenever the blob The blob is quite obviously a HANGMAN HANGMAN player or his robots score a direct hit on thinking creature and a capable The space monster itself lurks the player's tank it turns him into dodger of the player's missiles. It Save a soul from transcending at the top of the screen behind a a little human creature skating to also has a mean streak which will into the stratosphere simply by bank of robots which form the find refuge behind a shield. Each send him hurtling down from the using your brain to unravel one main part of the tentacled blob's time he needs another reserve top of the screen to finish the word. attacking force. Each robot is tank one of the shields disapplayer off, if it senses victory The game hangman which has equipped with a cannon from pears from the screen, leaving much more interesting than the long been a great favourite with which he hurls down bombs and the player more open to enemy unthinking invaders. schoolchildren has now been a shield which he can use for fire. If he is hit while tankless the The two different varieties of transferred to your video screen. protection. It sounds quite game ends in victory for the monster also make a change from This game for the Interton impregnable but the robots' Space Monster. the usual green meanies and VC4000 follows that old guessing weakness is that their shields Space Monster is the closest their numerous imitations. game popularised years ago. The must be held to one side for Philips has come to a space The Space Monster Videopac computer selects a word which them to fire. invaders' type game. is available from G7000 stockists the player, or players, must try A tank is your means of attack But it does have some innovaand costs around the  mark. A and guess. and defence. You have three tions all of its own which make it worthwhile alternative to the Quick thinking is also import reserves and three shields to attractive to would-be buyers.classic game. ant in this game, because you must guess the right word before the man on the screen is hung. Each time you place a letAtari is following the current ter of the word incorrectly a trend of producing cartridges PACKMAN section of a hanging platform and based on the most popular its scaffolding is added. Before arcade games. Due out in distributors' shops These are displayed on the you know it the entire frame of The latest addition to be in April, this version sticks screen where the action took the scaffold has been erected in turned into video computer sysclosely to the original concept. place. And a fruit is displayed at front of your eyes. The next tem form is 1981 success story. You operate a circular mouththe centre of the screen which stage is the completion of the Packman. opening creature which speeds can also be consumed for extra victim's body itself. along the paths of a maze, some points. Whenever you make a mistake times referred to as a house. With every cleared screen a in the formation of the word one Littered along the paths are small new fruit from the series, which limb of the convict is added. dots, each one representing is worth more points, appears The game ends either when points, for the hungry Packman within the labyrinth. you have guessed the word corto consume. There are three lives for your rectly, in which case you emerge Other characters in the maze man to play with during the as the winner. Or, if you can't are ghost-like creatures which game, and as play progresses the unravel the hidden word the poor move out from a central square number of ghosts increases, mak unsuspecting victim meets a very of the maze at regular intervals. ing your life more difficult. The untimely and unpleasant death. These run around the corridors, game continues as long as you Hangman is written in a 4K sometimes chasing your gobble. keep your lives without being ROM cartridge and is produced man and sometimes with you in devoured by the ghosts. When by Hanimex for Interton. It is pursuit of them, if you have manyou clear the maze of all the dots, available through the firm's UK aged to eat an energy post. the screen flashes up a new one. dealers ranging from Asda Successfully chasing and Available from U.K. distributor Supermarkets to high street munching a ghost, helps the Ingersoll this top of the range specialist shops. Hangman's player to score bonus points. cartridge costs .95. retail price is listed at .95. THINGS THAT GO MUNCH IN THE NIGHT "


"CENTRES TV GAMES CENTRES TV GAMES CENTRES BAFFLED BY THE BLACK AND WHITES TAKE THE TRENCH TO DARTH'S STAR commonly known, is displayed a BURN UP THE CIRCUIT BACKGAMMON, CHECKERS STAR STRIKE Two traditional board game favourites have been given a new Relive the final conflict of Star lease of life through the video Wars against the Empire's Death medium. Star when failure means your Checkers and backgammon planet's destruction. have been transferred to the Take the role of Luke television set via the Interton Skywalker on his do-or-die misVC4000 Video Computer system, sion to blow up Darth Vader's for enthusiasts who cannot giant man-made planet. In Star always find human opponents to Strike you have to guide your play against. Star Cruiser through space, Both are easy boards for the dodging enemy space fighters as computer to display and combine you travel to the Death Star. simple rules with plenty of scope Missiles whistle past you and for tactical play so the computer you must retaliate with the makes a worthwhile opponent, deadly laser guns positioned on even it if it will have a tendency your star cruiser. If you successto play safe. fully navigate through the space Checkers or draughts as it is hazards and reach the narrow commonly known, is displayed as trench, which you must fly along a board and pieces and there is to destroy Darth Vader. no deviation from the traditional Turbocharged cars are currently Expert flying skills are vital for rules. You can play either black or burning up the formula one race GRAND PRIX success because the trench is white black goes first and tracks and now you can catch lined with obstacles and filled then try to out-think your comup with these high powered combine speed with safe driving with enemy fire. Use your photon puter opponent. Be wary of the machines in this latest Activision to come out on top. torpedoes and maneouvre your computer if it appears to be offergame. Grand Prix is produced by ship away from the attacking ing up a sacrifice it probably You are at the wheel of a Activision for the Atari Video Crossfire like laser posts has something nasty planned for highly tuned turbo race car lined Computer System and has good positioned on the walls and floor. you. up on the grid for a Grand Prix. graphics and sound effects makJudge the distance from your As usual the opening strategy The circuit ahead is filled with ing the game more realistic. It ship to the trench carefully and determines who ends up with numerous hazards which you sells for the standard price of when you approach the last few the most kings and that is the must overcome with expert conE14.95. miles focus your sights on that player who will usually win the trol of the Atari joysticks. Apart Philips' new concept in video single exhaust vent the only game. from avoiding other vehicles games combining a television weak spot in the trench. Backgammon too keeps to the watch out for oil slicks. If you adventure with an actual playing If you've got an Intellivision, traditional rules but without the drive over them you're taking a board is to be unveiled this Star Strike is available from stockgambling element, it is not as risk and it could cause a multiple month. ists now, the price is .95. skilfull as the original. It will, pile-up. Quest for the Rings, which Intellivision owners can also however, help to sharpen up the Manoeuvring the car round featured in our March issue, is subscribe to a new newsletter players' skill at outmane ouvering the circuit is tricky. Not only are scheduled to be on distributors' produced by Advanced Conan opponent on the board. And it there sharp bends to contend shop shelves in April. A price is sumer Electronics, which gives will teach beginners the folly of with,.but you also have to drive still to be decided but it is likely details of the latest cartridges leaving an exposed piece in a your car over narrow bridges to be more expensive than the and new developments planned vulnerable position. The race is run against the standard Philips Videopac price for the Intellivision and Acetronic For those of you who have clock which means you must (.95). MPU1000 never played the game, it involves moving counters around the board in the opposite direction to your opponent and trying to get yours home first -but if a counter is left alone it can be captured by your opponent and returned to start. These cartridges are available from retailers in the U.K. from specialist dealers and some large department stores. The retail price is .95 "


"AT LAST! Sinclair ZX81 NEW RELEASES DICTATOR VIC SOFTWARE VICMEN Another great adventure game from Bug-byte for the 16K ZX81. This time, you are the president of a small state. The object of the game is to avoid revolution, escape assassination attempts, and maintain your popularity while managing the secret police and army, and maintaining a secure economy. This is a very complex simulation, utilising the whole 16K, and the cassette comes with an 8-page booklet giving full instructions and hints on how to survive. Can you stand up to the pressures of life as a dictator, and prevent unrest from spreading before it's too late? PRICE .00 A full-feature version of the popular \"Puckman\" arcade game for the UNEXPANDED VIC Written entirely in machine code for fast action SUPPLIED ON CASSETTE at .00 CONSTELLATION Turn your ZX81 into a telescope! This program will produce a simulation of the night sky as seen from any chosen point on earth at any time this century. You can point your \"telescope\" in any direction, move it up down, left and right, zoom in or pull out, and display the stars by magnitude or constellation. PRICE .00 VICGAMMON Standard Backgammon game for the VIC with 3K expansion Rapid computer responses Instructions on how to play are included SUPPLIED ON CASSETTE at E7.00 OTHER ZX81 SOFTWARE FROM OUR RANGE:ZXAS assembler .00 INVADERS .00 ZXDB disassembleridebug .50 3D OXO & MARS RESCUE E4.50 MULTIFILE filing system .50 VIEWTEXT .00 THE DAMSEL & THE BEAST .50 STARTREK .00 NOTE: all require RAM pack More VIC software will be available by the time you read this. Phone 051-227 2642 for details. Generous DEALER DISCOUNTS available-phone Dave on 051-227 2299 for details ACCESS BARCLAYCARD orders accepted on 051-227 2642 (24 hrs) 98-100 THE ALBANY OLD HALL STREET LIVERPOOL L3 9EP BUG-BYTE SOFTWARE ACORN ATOM SOFTWARE CHESS 747 Acorn Atom INVADERS 256 E PLA Acorn Atom FRUIT MACHINE 102XL241 202020 * BYTES BYTE NUDE NUDGE NUDGE RESPIN mum The hea FLIGHT SIMULATION PROGRAM FOR THE 12K ATOM Written for Bug-byte by a 747 pilot Accurate simulation of a 747 cockpit display aspeed audeat of climbaudeHape we, and graphic display of horizontal situation and del allows you to guide your car to the landing strip On making your final approach the display changes to a high resolution 3D rep resentation of the runway coming up to meet you. Areal of skill Finding the runway que challenge landing s lys even more difficult. If you succeed, you are awarded as a rating and the chance to take off and try again REQUIRES FLOATING POINT ROM t TOTAL EL. 90 \"A brilliant incredibly fat model with lovely sound & graphics Your Computer Nov 1 BK graphics mode 2 expand your Alam. It is a 02020202 YA 1241 ABCDEFGH and for your computer Nov 01 12 graphics THE PROGRAM YOU VE BEEN WAITING FOR Fantastic machine code chess game for the 12K Atom Features includes thighs alphanumerical many levels of play Casting & en passant computer plays black or white Suplied onc e with instructions BACKGAMMON BASIC) 4. GALAXIAN gammon board and allows you to play the standard DONT FORGET OUR PRICES INCLUDE VAT & POSTAGE * Fantastic high-resolution (mode 4) arcade game with fast-swooping aliens, excellent sound effects, and high score. 12K PRICE .00 onds and the program will no t Dice throwing is controlled by the com moves LUNAR LANDER 112K, BASIC & se, Gr. Mode A highly addictive arcade wyle program. A rugged LABYRINTH 112K, F.P. BASIC, GR MODA sound) High-resolution colour graphics (also effective in Black & White make the mare program one of the best the bewildering array of corridors of the 30 x 15 call random m e, you can call up to a 20 map of the maze in the harder game option, this map shows only the portions of the man which you have explored to land your crant safely on the flat areas, by varying the thrust of your main & steering rockets. You Succeed, the ship takes off and you have to try to land continues, until you have reduced 3 ships to heaps of rubbie On screen readout of fuel and score. Several skill levels A record kept of the high score. If you are a suficiently expert plot you will be rewarded with extra ships Definitely aut above the average lunar GOLFISK, FP BASIC An 18 hole, par 72 course, complete with airways, rough, bunkers, trees, streams & greens. Skiland careful club selection are required to get round with good score. To make things more difficult, you have to specify a fault in your game, which the program will reproduce, and your handicap. At the end of the found the program produce your corecard for the round A highly entertaining program, which is likely to have you uplate into the right training for a part 5.00 REQUIRES THE FLOATING POINT ROM ALL OUR PRICES ARE INCLUSIVE! Please cross cheques POS make them payable to \"Bug.byte Payment may be made by Access or Bare laycard, and there is a 24hr answering service on 051-227 2542 the centre of the more and then escape through the including the dreaded Minotaur) are loose in the man, and you will have to get your past them The types of mon present and their weapons can GENEROUS DISCOUNT AVAILABLE FOR DEALERS PHONE FOR DETAILS REQUIRES THE FLOATING POINT ROM BUG-BYTE SOFTWARE 98-100 THE ALBANY, OLD HALL STREET LIVERPOOL L3 9EP 20 COMPUTER & VIDEO GAMES "


"Will a chess computer ever be able to take on a grandmaster and give him a challenging game? Well, maybe the masters of the game will become wary of the machines after reading the results of a fascinating experiment reported by grandmaster Raymond Keene in Massacre at Merano his account of last year's world championship between Anatoly Karpov and Viktor Korchnoi. After the match some of the positions from the eighteen games were put to Sci Sys Chess Champion Mark V, one of the strongest of the commercially available chess machines. The results were impressive on a number of occasions the computer was able to improve on the play in the match. The following position occurred in game nine, with Korchnoi White. White again has to play 42. Q-KB1, to avoid checkmate and then 42. ... R-B8 wins White's queen, more quickly than by the line chosen by Karpov! In the next position, Korchnoi Black with very few minutes left to reach the time control on move 40 had hastily moved his queen to Q4. Karpov now has 35 minutes to make his next move but probably to keep up the pressure on Korchnoi he replied instantly and played 40. N-Bl to save his threatened knight. contest arranged against grandmaster Dr John Nunnan extremely strong chess-problem solver at the end of a recent international tournament at Brighton. Man and machine were each set six difficult problems, selected by the vice president of the Problem Commission of the International Chess Foundation. One of the problems was this prize-winning composition by the Soviet problemist L. Zagorujko, which appeared in 1972. It is White to play and mate in four moves. Nunn was unable to find the solution to this extremely difficult problem, but the Mark V did so; in fact it found three solutions an extremely embarrassing outcome since a problem is considered spoiled if there is more than one solution found. ti 1 * 1 A 1 D Korchnoi has just played 41. Q-Nlch and Karpov now replied 41. ... P-N3 and the game continued 42. Q-KB1 (forced to avoid mate on KN2), Q-B4ch; 43. K-RI, Q-Q4ch and white resigned (after 44. K-N1, R-Q8 wins the queen). This win gave Karpov a 4-1 lead -draws did not count in the match. It is hard to imagine that Black's play can be improved here, but in the diagrammed position Chess Champion Mark V, after about 30 seconds analysis, found the improvement 41. ... R-QB7! This kind of move is difficult for a human player to perceive, since it pins Black's rook against his king, an action which tends to be avoided instinctively by strong players. In this case, Korchnoi now played 40. ... B-K5! With an irrestible attack on White's king knight pawn. Karpov played 41. B-B4 and adjourned the game until the next day, but resigned without resuming after Black's 41... BXKNP: 42. N-K3, QB6: 43. NXB R-K7; 44. Q-Q1, QxBPch: 45. K-RI, QxN mate is one likely continuation. Karpov's blunder in the diagrammed position gave Korchnoi his first win of the match. How did Mark V handle the position? After 38 seconds' analysis, it found the far superior alternative 40. N-K2! Now Black cannot take the knight without losing his queen and white threatens 41. N-B4 which would fork Black's queen, rook and bishop, attack the queen pawn and defend White's own king knight pawn. These and other examples clearly impressed grandmaster Keene, not least because of Kar pov's decisive and accurate play throughout almost all the match. The same machine scored a further success in a challenge As an indication of the complexity of this problem, the reader is invited to work out the analysis after the key move 1. R-K8! For a computer to do this is impressive, but to find two other solutions was beyond the powers of the many problemists who have examined the position since then. However, there is a considerable difference between analys. ing a problem position and play. ing a game. The Mark V's achievements should not be taken to suggest that a grandmaster program is imminent, but they do show that in some areas of the game computers are already capable of more effective deep analysis than humans. By Max Bramer "


"F LONDON CON WPUTER CLUBS Proudly presents SSOCIATION OF THE 3rd LONDON COMPUTER FAIR APRIL 15th 16th & 17th 1982 10am-6pm (7pm 16th] Including: Retail Exhibitors  Hobbyists Club Stands  Seminars Workshops Bring and Buy Sale (17th only) Admission .00 POLYTECHNIC OF NORTH LONDON THEATRE  Opposite Holloway Rd. tube station O SPONSORED BY EDUCATIONAL COMPUTING, COMPUTING TODAY and The Polytechnic of North London INFORMATON INFORMATION82 TECHNOLOGY 22 COMPUTER & VIDEO GAMES "


"BRIDGE Here's how the Fidelity Bridge Challenger Mark I had been at Challenger dealt with a recent BY ALAN HIRON its weakest, failing to draw hand encountered during trumps or sometimes drawing match-play. were instructed to play a strong them too enthusiastically. Although the Mark II Chalno-trump 16-18 points. It It had never seemed to count lenger has the facility of shouldn't have made any differtricks and refrained from taking generating its own random deals ence to the final contract, but: finesses that were necessary. it seemed more sensible to try it West East Perhaps over-zealous advertisout on an actual hand. This way INT 4C ing had suggested that Chalyou get a human comparison as 4S lenger played the cards well. well. This was the hand, dealt at 5S 7D Both large stake money matches love all: pass and legal action were North The Four Clubs bid and threatened by its detractors and SK 987 indeed the Five Clubs bid — certainly the play had to be HQJ7 were Gerber and on finding tightened up. D Q 107 South with two Aces and two Even now there are problems. C 32 Kings North plunged on to the It is extremely difficult to lay West East grand slam. It is perfectly true down a set of anxioms on how to SA 5 SJ 10 that if South had held DQ as well plan the play of a hand there H A 10 94 HK 6 are so many variable factors. DK53 DAJ 98 62 On the deal we have been CKQ 64 CAJ 5 considering Challenger had no South trouble at all in its Three noS 6432 trump contract. After the lead of H8532 a top spade, it cashed its nine D4 top winners albeit in a C 10 9 8 7 slightly odd order, but efficiently Setting the Challenger aside enough. for a moment, if you were a In the Seven Diamond conbridge player, in what contract tract, Challenger won the spade would you like to play the lead and, playing to the perEast-West cards? Six Diamonds centages, correctly played off DK is undoubtedly the best spot. and DA. But the Queen did not It makes if the trumps are 2-2 fall and the slam was doomed. or the Queen is singleton and But when Six Diamonds was there is the extra chance that as his other high cards he would the final contract, things weren't even if a defender has started have bid exactly the same and so good. After taking the spade with a guarded Queen of Seven Diamonds would have lead and trying the top trumps diamonds he may have to follow been a doddle. As things stand, unsuccessfully, the normal play to three rounds of clubs. it is not an outrageous contract. is to try the clubs, hoping to get First Challenger was set to The next thing to try was a the losing spade away before the work with the instructions that it little interference bidding. Supdefender with the Queen of was playing a weak no-trump pose that over One Club North diamonds can trump. (13-15 points) and that there was overcalls with One Spade. Any tournament player would no opposition bidding. Its Should this affect things?. see this immediately and would auction went: Apparently it did for now the waste no time in trying it out. Not West East bidding went: so Challenger, who rather 10 ID South West North East weakly conceded a trump trick IH IS C IS 2D and so went one down without 3D 4NT pass 2NT pass 3NT even trying the Clubs. 5H 6D pass pass pass Perhaps he wanted to get pass Let us be fair. The grand slam started on the post-mortem and Not at all bad! The One Spade was not too wild, the small slam criticise his partner's bidding! bid was 'fourth-suit forcing' in distinctly better, and nine tricks Incidentally, the best line of the best modern style and both in no-trumps were simple. But play doesn't work, but a finesse halves of Challenger's split perthe difference in valuation is of DJ the second round of the sonality valued their hands well intriguing. suit would have done. Whatever after that. What about the play of the Challenger's faults, he doesn't For a second run, East-Westcards? It was in this area that peek! COMPUTER & VIDEO GAMES 23 "


"INNOVATIVE TRS 80-GENIE SOFTWARE from the professionals Defend! First there was Invaders, then came Asteroids, and now DEFEND!!! Carrying on in the same tradition, Defend is a fast arcade type action game, complete with sound effects. Enemy spaceships come at you fast and furiously. If you succeed in shooting them down before they get your ships, you must still get yourself through a meteor shower (but at least they don't shoot at you) and finally, if you emerge unscathed, you must navigate a tunnel in order to get yourself completely out of danger. An enthralling game with excellent graphics, personalisation of highest scores and points bonuses. One of its best features is the crisp and immediate control the player has over the manoeuvreability of his ship which includes diagonal movement Machine language, of course, for speed. A matter of taste, but we think it beats Invaders and Asteroids. Suitable for TRS-80 Models I and Ill and all Genie models. Tape (16K) ........ ..00 + V.A.T. = .95 Disk ...........00 + V.A.T. = .40 MOLIMERX LTD AJ HARDING (MOLIMERX) A A . 1 BUCKHURST ROAD, TOWN HALL SQUARE, BEXHILL-ON-SEA, EAST SUSSEX. AMERICAN DU3055 TEL: (0424) 220391/223636 TELEX 86736 SOTEX G TRS-80 & VIDEO GENIE SOFTWARE CATALOGUE .00 [refundable) plus  postage. 24 COMPUTER & VIDEO GAMES "


"Ever since Prestel started three years ago, games have been the single most popular thing on it. That's not what it was designed for, but games are a very good way of finding out about Prestel. There are now dozens of different games, ranging from short and simple ones to fairly complex ones. ON SH GRID By Peter Linton Although Prestel runs on computers, there is a vital difference between it and even the smallest micro-computer. Prestel has no processing power. It cannot perform calculations, store variables or do clever things with the display at least, not at the moment, but it's coming. What Prestel does have is simplicity, colour and routeing. All games are therefore essentially games of choice. The key point about Prestel is that it is a computerised information system that anyone can use. All you need is a numerical keypad, and with that you can control and drive the computer. You don't need to be an expert. Colour is a very important element in Prestel — it gives it much greater impact than ordinary monochrome computer displays. There are six colours, plus black and white. Three are the primary colours — red, blue and green. A colour T.V. screen is coated in thousands of phosphor dots which give out these colours. If you mix the primaries, you get some surprising results — red and green together produce yellow. Blue and green become cyan light blue and red and blue is magenta. Mix all three primaries together to get white. If that puzzles you, think what would happen if you could shine all the colours of the rainbow back through a prism. You would not get a muddy brown colour, but vivid white. It's the same on a T.V. screen. Routeing is the secret weapon in Prestel. Each page on a T.V. screen has an invisible \"back\" side to it, with various bits of information on it. The most important thing after the page number is a list of other page numbers up to 10 of them. Suppose you are on page 12345, and number three on the routeing list is 7654321. If you press three, the Prestel computer is programmed to search that list for number three, and pick out that new page. Then it searches for that particular page among the 200,000 stored on every Prestel computer, and sends it back down the phone line to your set. The amazing thing is that all that takes only a fraction of a second. And it can be repeated as many times as you like. It is as if you had a filing cabinet from which you could extract a sheet of paper in an instant — and that sheet could call up further sheets just as fast. This facility presents great opportunities and challenges for Prestel designers. Effectively it means that you must think in ten-dimensional terms. Any page can lead to any of ten other pages, which in turn can lead to ten further pages, and so on, for ever. It is almost impossible to put that down on paper, which is only twodimensional, and things like flowcharts are usually little help. A Prestel designer therefore has to visualise a logical path through a maze of information and allow for all the alternatives. It can get pretty mindboggling at times, but it does provide a useful mechanism for games. It means you can provide a range of simple choices. All the player then has to do is to key the number of his choice, and this calls up the result with a new set of choices. A good example is a game called Superbike on 4782111 (pictured above). You are racing ex-world champion bike racer Barry Sheene, and you have to make a constant series of choices, whether to overtake him on the inside or outside. This routeing structure is the basic mechanism of almost every Prestel game, and a look through the games index shows the ingenuity that's gone into devising variations. By providing a steady series of choices, it can provide a large combination of different possibilities. The catch is that if you play the game again, you get the same choices. There is no randomising element. Another catch with designing a Prestel game is that you need to provide for every conceivable possibility, otherwise some players are going to get stuck. That can involve large numbers of Prestel pages for games where there are many choices. Think, for instance, how many different variations there can be in Noughts and Crosses. On Prestel that requires several hundred pages! Prestel games are not as \"intelligent\" as most microcomputer games. But there are dozens to try, and new ones being devised all the time. Now that you know how they work, you'll enjoy them even more! COMPUTER & VIDEO GAMES 25 "


"ARCADE KEEPING WARFARE IN PERSPECTIVE TIPS ON BATTLE ZONE Bate Zone \"\"unique game, hiting if they pass in front of you THE RECORD BREAKERS Patience is not usually demanded of arcade players, who are happier feverishly pushing buttons to destroy as much as possible before the next missile with their name written on it, homes in. of the plain. These are well worth Battle Zone a unique game, hitting if they pass in front of you where the player is encouraged (5,000 points) but it can be lethal to manoeuvre until the right to chase them, even though they Breaking new ground on arcade record and it presently stands at opening to hit back comes along. don't fire back, as a tank may use machines is turning into an 30,100,000, knocked up in 50 The game simulates tank warthis opportunity to creep up on endurance test as much as it is a hours by a New Yorker. fare giving a view from inside the you. test of skill. David Birkett claims all four tank. Tank controls are also faith. With the missiles, which fly This is proved by the fact that Kent players have previously fully duplicated with two levers towards you from the back of the four students from Kent Univer been over the million mark: \"1 which can be pushed into forscreen, it is possible to increase sity are planning to spend eight have scored five million in a ward or reverse position simulatyour chance of hitting them by days at the controls of an double game which lasted eight ing the two tracks of the tank. going into full reverse and waitasteroids machine to put their hours and we were left with 113 Beginners quickly learn that ing until they get up really close. names in the record books. bases. pushing both levers forward it is also possible to put an David Birkett, David Hill, Tony \"We will have no shortage of sends their tank off in that direc obstacle between you and the Thomas and Alan Tilling are the people willing to invigilate the tion, while pulling them back missile which will cause it to four whose endurance will be attempt as we are being sponsends the machine into reverse. miss but it will come back to try tested in shifts on the universored for the rag week charity With one at full reverse and one again be ready for it. sity's machine in Canterbury. As and any money we make will be at full forward the tank turns A good player uses the radar this issue goes to press the unigoing to spina bifida sufferers. quickly on the spot. to place tanks as half of them will versity's rag week will be taking Are you record-breaking But even with a good shooting materialise behind you. Scoring place around the four of them as material? From our next issue we eye, this knowledge is not 150,000 will give the player a they attempt to return an will publish some of the best enough to help a player survive 15/20 minute game but beginners unbeaten score of 100 million. Scores we have heard of on for long. As turrets swivel in your should watch for games which If their attempt succeeds it popular arcade machines to give direction, the best tactic is to go offer extra tanks for your money, will leave the present world top scorers something to aim at. off diagonally to escape. to learn on. Our thanks go to record for dead. Atari, which If you can beat our highest This is achieved by pushing Simon Eyre of Waterlooville, in manufactures the Asteroids Scores and are willing to prove it, one lever hard forward and the Hants, for the tips. machines, monitors the world please write and let us know. other only halfway forward. The enemy's shells will fall just behind you. When you have gone right past the tank, check the After Asteroids, came Asteroids and they move around the screen radar to see the enemy's position De Luxe and now Space Duel SPACE DUEL in tandem, firing independently, behind you. Then reverse hard continues Atari's efforts to turn but moving as one. until it appears on the screen rock-bashing into a fine art. under fire into smaller segments This takes some getting used quite close up and turn on the Space Duel's asteroids are far of themselves. Alien spacecraft to and teamwork is very importspot. You will have two chances from featureless chunks of space still frequent the pathways beant when moving out of the way to get in a shot before the tank is debris though. They come in a tween them and your craft is still of an oncoming asteroid. One in a position to fire at you again. multitude of different colours and equipped with shields to protect craft can pull the other out of If you miss with both, then whirl through space, breaking up itself from rogue meteors. harm's way, but if both try to go repeat the tactics. One danger is But the most interesting feain different directions at once, that you may run into the enemy ture of Space duel is that two the meteors will come out on as you reverse and then you will people can play at once. It is top. be helpless but the radar check possible for both to take to the The advantage is the should prevent this. screen as enemies and go indiincreased fire power which can After 30,000 has been scored, vidually for a high score, or play blast an asteroid out of harm's the super tanks are unleashed, as a team to knock out as many way very quickly. these turn much faster but the asteroids screens as possible When both craft are on the same tactics work, although you between the two of you. screen at once, a good player can will only have time for one shot. A further break with tradition help a beginner to pull through Among the other inhabitants is that the two spaceships can as the game continues until both of this machine is a flying saucer team up to give real fire-power. A have lost the required number of which flies swiftly along the back chain is tied between the two lives. THE ART OF ROCK BASHING 26 COMPUTER & VIDEO GAMES "


"ACTION HERO WITH A YELLOW STREAK EXPLORE THIS OH-SO LENGTHY TOMB other six move up and down KNOCKS OFF UFF The treasure of the Pharaoh's TUTANKHAMUN tomb is awesome but so are AMIDAR the creatures that guard it! The monsters hunt in a pack The Earl of Carmarthen's some trying to get in behind you The Amidar may look like cuddly expedition into the mysterious and others trying to draw your toys but their touch is deadly. depths of King Tut's famous fire before leaping into some half The game which is named pyramid proved hazardous but forgotten recess. after these creatures combines arcade players have to face even your explorer has a limited the fashionable arcade themes of more terrors. amount of ammunition in his maze chase and space capture. The explorer who braves this weapon which occasionally In Amidar, you take the part of video pyramid resembles a carneeds replenishing. But his main a gorilla, who swings around the toon prospector character com deficiency is that he can only fire screen on blue bars which are plete with a bushy white moushorizontally and is in real danger covered in white fruits. As he tache and with tools strapped to if he ever gets trapped in a vertimoves along the bars he clears his back. cal part of the maze. them of white fruits. If all four This treasure hunter is also To help him avoid this happensides of a square all cleared the armed, which is just as welling the top of the game screen centre is filled in red and gradubecause he will have to face a offers a \"radar\" display of the ally the screen becomes a horde of guardian creatures in whole maze. On this the monpatchwork of red rectangles. this tomb. sters can be seen as white blobs, There are seven Amidars on This motley crew of monsters converging on you from the far the screen. One runs around the include a mummy and a cobra as end of the maze. outside four corners and the well as some less explicable Although it doesn't help you other six move up and down dungeon denizens. Their touch is much in dodging the advancing always turning the nearest deadly horrors, it does prepare you for corner. These creatures are not The labyrinth which leads to their charge so you can ensure a as intelligent as the Puckman the treasure is long and tortuous. long horizontal passage stands \"ghosts\" when it comes to huntbetween you and them. ing down their prey. LADYBUG You have three lives to try and All the dots must be erased to make it to the treasure but clear the screen and start on the Any gardener will tell you that these blue beetles appear rather they are not nearly enough second area of the game. This ladybirds are a force for good on slow and cumbersome and even especially since, you are time a framework of red lines the rosebushes. a beginner has a chance of doing returned to the beginning of the comes up on the screen and the They are now also undertaking well against them. But these are tomb each time the monsters player is transformed into a paint heroic feats in the arcade in a later replaced by some faster catch you. roller. The Amidars, which new maze game. pink beetles who track down the The biggest danger among the resemble toy cats, still undertake the player takes the part of ladybirds much more swiftly first batch of creatures is the their regular patrols of the the ladybug, which also gives its An interesting game for the sarcophagus-like being which is screen. name to the machine, and sets beginner but the controls for the invulnerable to your fire-or so The aim on this screen is to off on a spot consuming trip ladybird are not designed for he seems at first. In fact a use your paintbrush to pick up a around the maze. fluid movement which can result sequence of three hits will make yellow streak at the bottom of In this game the spots are few in frustration when they do not him turn away and rethink his the screen and extend it. With and far between and the purrespond quickly enough. avenue of attack. the Amidars making life as hard suers are in the form of large as possible you first have to run blue beetles which try to corner the yellow around the border of your rampaging insect. the nearest rectangle, filling it in But you do have one big with a bright green and pocketadvantage over your adversaries, ing the bonus score which the your ladybird can walk through space previously featured the maze walls, as these are From this start it is possible to hinged doors which the creature fill in the entire screen, with the can push open. really big bonus scores waiting As one way opens another is for you at the top. inevitably closed as the door It is important to keep a cool swings around in 90° to seal head as the Amidar are quite a different passage. The blue capable of turning away from you beetles cannot pass through even when they seem to have the doors. you surrounded. Just keep a The good player will plan to check on where the next corner block off the beetles completely, comes up and be sure that they surrounding them within four will turn down it. doors and leaving them helpless. COMPUTER & VIDEO GAMES 27 "


"The Sinclair ZX81 has a real poker face — it gives nothing away about its hand. No beads of sweat will form on its keyboard if it's bluffing on a Jack high and you won't notice its RAM-pack trembling with excitement if it holds a full house. In draw poker, claim the best players, the early part of the game is all mathematical odds and the final betting is all down to psychology. This program will hardly give the ZX8l a believable personality but it will help the uninitiated learn how to play poker hands and how much to gamble on them. The ZX81 deals out two poker hands, one to itself and one to its opponent, you. After a quick look at the possibilities of your hand, you must key-in how much money you are willing to gamble on drawing the right cards against the ZX8I's hand. The ZX81 will always cover your bet and often give you odds if it thinks you have made a rash decision. Then after you have changed your hand in search of that elusive full-house, the ZX81 does the same and it's winner takes all. Not quite Cincinnati Kid stuff but it will give a good understanding of the game and show why experienced gamblers never draw to an inside straight. After all everybody should know how to play poker, if only to help them understand why the west was as wild as it was. Bu ZX POKER 28 COMPUTER & VIDEO GAMES "


"TAMT =100 ON 598 INPUT B 595 PRINT AT 8,;\" 600 IF BE THEN GOTO 780 510 LET F=1 M 1     616 LET 617 LET 53SHEARTS. www DOI 110 =\"CLUBS\" IAMONDS\" =\"SPADES 20{1*2) AUTO H  HHHH UNDOOOOO00000 OOOOHOOOHHUMMOOOOOOOOOOOOOOO. U CUJUCI CUCCU 00000 DONN0000-+ HAM ( VAR >XONOMHO UITZIIIIIIIIIZCZU an WHHHHulu lui o WWHHHHHH Wu Wu WwWw wWoowww Count             620 UB 6000 630 F= THEN PRINT AT 8,0; \"I NURLID REPLY TRY AGAIN\" 64@ IF F= THEN GOTP 590 651 LET TEMP =C (N) 710 PRINT AT 8,; \"MY HAND : 720 PRINT ;\" 730 NEXT D 800 REM ANALYSE COMPUTER HAND 810 GOSUB 2000 820 GOSUB 2070 838 IF X12) <6. THEN PRINT \"I CHA 840 IF X (2) <6 THEN GOTO 2145 844 IF X12) = AND T418 THEN LE 845 if X(2) =9 AND GS > THEN LE TGES STRO K (5) H$ 18, 14) H$ (1) =\"STRAIGHT FLUSH\" H$ (2) =\"FOURS\" H$ 3) =\"FULL HOUSE\" (4) =\"FLUSH H$ (5) =\"STRAIGHT HS (6) =\"THREES\" H$(7) =\"TWO PAIRS H$16) = \"ONE PAT ze FoR SES TO 14   TO 0 N=N +1 258 LET CIN) = 10 *R+S OR N=1 TO 52 ET M=INT (RND *52) +1 LET T=C M) LET C(M)=C(N) LET CIN) =T NEXT N SLOL 340 LET N= RUNS ON A ZX81 IN 16K BY DAVID LAMB 341 PRINT \"YOUR HAND : 3423PRINT FOR D=1 TO 2 FOR T=1 to LET NEN+1 FoR PL TO LEN STR$ G ET HIT,D) =C (N) *10+T ET TEMP=C (N) OSUB 4000 540 PRINT T; TAB 10; R$;\" OF \";S$ NEXT T PRINT IF AMT > 9 THEN LET MEINT (AM 562 IF AMT <10 THEN LET M=1 570 IF D=2 THEN GOTO 800 571 PRINT \"BET NOW MAXIMUM ST 572 INPUT STAKE 573 IF STAKE >M THEN PRINT AT 8 ; \"SORRY YOU MAXIMUM BID IS  574 IF STAKEM THEN GOTO 572 575LET AMTERMT-STAKE 576 PRINT AT 8,0;\" 580 PRINT AT 8,0; \"ENTER NUMBERS OF CARDS TO CHANGE\" ET I=UAL G$ (T) ET RI,D) = (ID) #10+VAL Q$ LET Q$ (I) =\"0\" 0 NEXT T 910 FOR T=1 TO go IF @sit) < THEN LET B=B* 10+VAL OST) 930 NEXT T 935 GOSUB 7000 940 IF B<10 THEN PRINT \"I CHANG E CARDB 950 IF 6 >10 THEN PRINT \"I CHANG  NOODOH + SARDOSub 4200 COMPUTER & VIDEO GAMES 29 "


"IZX81 USERS From «BYG BYTE' comes a fully compatible, assembled, tested and guaranteed 16k RAM PACK PLUG-IN MEMORY Send to Name.......... Address.. All cheques and postal orders made payable to CAPS LTD Dept. B And forward to 28 The Spain Petersfield, Hampshire GU32 3LA Allow 28 days for delivery WHY PAY MORE? Fully inclusive price each 1.95 30 COMPUTER & VIDEO GAMES "


"N Q000 8206 REM FOURSO 2 UD J(I +2) = RETURN REM FOURS FOR I=1 TO 2 IF WII) = (1+1) AND JOI+2) = AND JI+1) =(I+2) THEN GOT 20 NEXT I 30 RETURN LET X (D) = 2 LET GEI+1000+ (1+1) #100+ {1+2 RETURN REM FULL HOUSE IF XD) = THEN RETURN 2020 FOR TE1 TO 2 000+0HD BOOM0009000SHOHOHOHOS +90988HO wwwwwwwwwwwwwwwwwwwwwwwwaaa  H + ++++ UCU OOOOOOOOOOOOOOOOOOOOHHHHHHHHHHH In N00001 OOOOOO nos DOHONNON O ' IN E RETURN REM FLUSH FOR I=1 TO as EXT: LET S4= LET GS=2 FOR I = 1 TO 5 LET K (I) =H (ID) -JCI) #10 LET TOK (I) =T EK (I) ) +1 NEXT I su 2099 REM ANALYSE HANDS FOR D=1 TO 1920 GOSUB 2000 GOSUB 2070 NEXT D 104. GOTO 2145 2008 REM SORT HAND 2010 FOR F=1 TO 1 2030 IF HIT,D) YH (T+1,D) THEN GOS UB 3000 3040 NEXT T 2058 NEXT F 2065 RETURN EM ANALYSE HAND D XD) = ET @= @ LET G=0 R I = 1 TO 5 2002 LET JETI =INT I,D) /100) ET TEMP=HEI,D) ET HEID)=INT CHCI,D)10) ET Q=0*1 +TEMPHE OR C=1 TO 9 OSUB (3090+ 100) IF (D} < THEN LET C=9 NEXT C iTg==| 7 LET YD) EJ VAL G$ (LEN G$)) RETURN 5 REM PRINT RESULTS LET U= LET C=10 FOR D=1 TO 2 IF XID) < THEN GOTO 2154 LET TEMP=H 15,D) GOSUB 4.000 PRINT AT 0,0; R$:\"HIGH\" GOTO 2155 PRINT AT V. CH$ (XD)) LET U= LET C=8 NEXT D REM PRINT SCORE 2160 PRINT AT 16,0\" 2165 PRINT AT 16,0 217 IF X (11) X (2) OR (Y (1) SY (2) AND X (1) X (2)) THEN GOTO 2220 2180 IF X (1) X(2) OR CY (1) >Y (2) AND X (1) =X (2)) THEN GOTO 2260 2190 PRINT DRAW YOUR MONEY RE TURNED LET AMT AMT +STAKE 2200 GOTO 2291 210 GOTO 2230 20 PRINT \"YOU LOOSE 3 LET WIN=STAKEHO TX {2)) LET AMTEAMT-WIN IF AMT <1 THEN PRINT \"YOU HA RUN OUT OF MONEY IF AMT <1 THEN STOP LET ODDS=O (X (2)) 8 GOTO 2280 50 PRINT \"YOU WIN\" 70 LET WIN=STAKE*O (X (1)) 2 LET ODDS=O CX (1)) PRINT \"E\"; STAKE;\" AT \"ODDS TO 1 =  WIN; + \"; STAKE; 22STARE 2291 PRINT YOU ARE E, AMT; \" IN \"LEWIN+STAKE\" PRINT \"ENTER FOR ANOTHER 2310 INPUT 3328 IF <> THEN STOP CLS GOTO 279 REM SURP CARDS LET F= LET TEMP=HT,D) LET HET D} =HT +1., DI LET HIT+1D) =TEMP RETURN REM STRAIGHT FLUSH GOSUB 3400 LXD) = THEN RETURN LET XD) = OSUB 3500 F XCD) =@ THEN RETURN LET APP SAMT U IN +STAKE #WWW+ Hwwwwwwwwwwwww FOR_I=1 TO 4 IF TUI) =S THEN LET XD-4 IF T (I) = THEN LET S4=T NEXT I IF XD) =4. THEN LET G=12345 IF S4=3 THEN RETURN FOR ISITOS IF KPI) =S4 THEN LET GS=GS#1 NEXT I 84. RETURN 0 REM STRAIGHT @5 LET T4= 3510 IF (1 +4 =J (2) +3 AND J (3) +2 =J (4) +1 AND J (5) J(1) +4 AND J (2) +3= (3) +2 THEN LET XD) -5 3520 IF J5) = 14 AND J1) =2 AND W (2) =3 AND J(3) =4 AND J14) =S THEN LET XD) =5 3530 IF J 1) +3= (2) +2 AND J(3) +1 354. IFJ (2) +3= (3) +2 AND J (4) + 1 J(5) AND (3) +2=J 4) +1 THEN LET T4 =2345 NONOH000 SO HOM LET X112515 COMPUTER & VIDEO GAMES 31 "


"home computers Atari's expanded to 32k Doubles the memory A ATARI NATARI DOO 400 with 32k of RAM only  800 with 32k of RAM only  excl. VAT excl, VT SPECIAL SPECIAL FEATURES FEATURES . One cartridge Expandable via slot.  Ridged plug-in cartridge to pressure sensitive keyboard. 48K.'. Two cartridge Recessed system keys. slots. Full typewriter .00 excl. VT style QWERTY keyboard.  Monitor jack for use with high quality monitors or VCS machines. .00 excl. VAT STANDARD FEATURES 400/800.  6502 central processor unit.  10K ROM Operating system, 8K ATARI Basic.  Four game controller sockets.  16 colours each having 8 different luminosities.  4 sound generators with four octave sound range plus volume and distortion Controls.  High Resolution graphics, 7 modes, highest resolution 320 x 192.  Control for up to four disc units.  Control for printers, peripherals and communication devices.  Alternative languages, e.g. MICROSOFT, PASCAL, etc.  Full screen editing.  Plugs into your own television. Tape deck-for 400 & 800 .48 excl. VAT. Joy stick controller .26 excl. VAT. Le Stick .74 excl. VAT. Software Ask for details of our extensive range of software Goods required Price MAIL ORDER to Adda Home Computers Ltd. FREEPOST, London W3 6BR or telephone your order 24 hours a day) to 01-992 9904 quoting your Visa. Access or American Express number \"I enclose a cheque, made payable to Adda Home Computers Limited for * Please charge my Visa/Access/American Express account My acount Add 400 post, packing and insurance for Total E number is special deal and .00 post, packing and * Please add my name to your mailing list insurance for all other items. Add 15% to all *Delete as applicable prices for VAT Date Name: SHOP ADDRESS Adda Home Computers Lid. 154 Victoria Road, Acton, London, W3 Address: (near North Acton tube station) Tel 01-992 9904 OPEN: 10am-6pm (Tuesday-Friday). 10am-5pm (Saturday) TERMS AND CONDITIONSAll goods sold subject to Adda terms and conditions of sale. Full details available on request, but include: 7 day money back guarantee, Adda 12-month hardware warranty. Please allow 21 days for delivery. Allow 7 days for personal cheques to be cleared. Quoted prices are exclusive of VAT =adda32 COMPUTER & VIDEO GAMES "


"ETURN Uw CAM YOUR HAND : TWO PAIRS 5 OF HEARTS 7 OF CLUBS JACK OF DIAMONDS 5 OF SPADES 7 OF HEARTS MY HAND : ACE HIGH KING OF SPADES ACE OF SPADE 9 OF HEARTS 3 OF HEARTS JACK OF CLUBS YOU WIN 25 AT 6 TO 1 =  + es STAKE =  YOU ARE  IN CREDIT ENTER FOR ANOTHER DEAL 355@ IF (5) = 24 AND (1) =2 AND (2) =3 AND J(3) =4. THEN LET T4 = 123 3560 IF XD) =5 THEN LET G=12345 3570 RETURN 3603 REM THREES 01 FOR I=1 TO 3 IF UTI) = (1+1) AND J(I) =JCI EN GOTo 364 NEXT I TXD) = 6 3650 LET G=1#108+ (+1) *10++2 68 RETURN LET TEMP M 2 PAIRS FOR I = 1 TO 4 3720 IF JFI) = (1+1) THEN LET TEM F J(I) = {I+1) THEN LET GEG 100+I+10+I+1 NEXT I F TEMP=2 THEN LET XD) =7 M 1 PAIR T G =0 SUB 3700 3818 IF TEMP=1 THEN LET X (D) S M HIGH CARD T XD) = 9 T G=5 TURN M RETURN RANK TREINT (TEMP/10) TS=TEMP-R*10 + RS=STRSR FR=14 THEN LET R$=\"ACE\" IF R=13 THEN LET R$ =\"KING\" F R=12 THEN LET R$=\"QUEEN* IF R=11 THEN LET R$=\"JACK\" ETURN EM COMPUTE CARDS TO CHANGE ET M= OR I=1 TO 5 IF $ (I) (\"\" THEN LET MEM* w NNNNNNCNNNNNN.00000000000000DAAAAAAAAAAAAAAA 000000000000* OWwwwwwwwwwwwww ou no NUME DONNNNNNN00000000 . Woulu lu lu lu lu WOL + UL. WIL +100 HOU+UNO HOO9W NOOOOOOO000000000000000OOHOOOOOOOOOOOOOOOOOOOOOOOOO 000000 QUIJONQO000000000-H: HOOO0000000 HOLCU.HIZOJEKJUH HHZHOU JOHOKJJJHHHHOUJLN ZXJJLMWZHILJOO Q ZOLLH + OL lui il w w WILLILI. WW WOLI W JOLFUL OWOCOW W HUZULON .  OOL (DUN 0100 E CARDS 5$ TR H RI=1 TO LEN STR$ B B ${I} > \"5\" OR B$ (I) ( ##IZH zin TH 1 F FEO THEN RETURN FOR I=1 TO LEN STR$ B T NEN+1 T TEVAL M$ (I) LET HET D} = (N) *10+ LET TEMé=C (N) GOSUB 4000 PRINT AT QUAL (5$ (ID) +0), 10 6120 PRINT AT VAL (B$(D) ) +0), 10 \";S$ (5) XT 1 TE=STRE FOR F=1 TO 2 FOR T=1 TO LEN STR$ 0-1 IF B$ (T) >B$ (T+1) THEN GOSUB 7050 NEXT T 7060 LET BEVALB*TO LEN STR$ 7090 RETURN 100 REM SUAP NUMBERS 7105 LET F=0  LET T$= $(T) LET ET) == LETE] =  RETURN + COMPUTER & VIDEO GAMES 33 "


"STARTER MESSAGE TO STARFIGHTER: Your mission is to destroy enemy craft and bases in this sector. Our intelligence service has been unable to obtain exact locations of these targets but your shipboard computer will aid you in the search. Your ship is armed with neutron mis siles and phaser weapons. Beware of asteroid storms in your sector. GOOD LUCK OK space fans -the object of this game is to search and destroy targets positioned randomly around the galaxy which in this case is represented on the screen of a 40 column PET. The game uses the whole screen for the galaxy, which is poked into position. This allows moves and action to be displayed as and when they happen. A second screen displays the co-ordinates of targets, starfighter and starbase of shields, energy, weapons and the number of targets available. The starfighter which you pilot can stock up with weapons and refuel at a friendly starbase. All major parts and sub-routines of the program are prefixed by REM statements describing their function. Other significant parts of the program are: Line 119 number of targets per sector. Line 125 — frequency of starbases. Line 142 — frequency of asteroid storms. Line 150-hostility of the targets, this increases as the number of targets decrease. Line 158 frequency with which the targets move and attack. Line 620 frequency with which new targets enter the current sector during combat. Lines 899-910 prevent the program crashing by loading the commands into a file. RUNS ON A PET IN 6K 50 REM STARFIGHTER 55 REM P. B. MORGAN. HORTHVILLE. 120381 90 GOSUB 5000 BY P. B. MORGAN 99 REM INITIALISE VARIRELES 199 ELRDIM S(36)K SE=2600 W=400 H=8 105 TII=\"000000\" 189 REM INITIALISE MEW SECTOR (5) 110 D=31 GOSUB 450 115 FOR NED TO 36:S(N) G: NEXI 116 FOR N=11 TO 34: GOSUB 200 I NEXT 119 C=INT(6*RND(19 IF THEH C#k 120 T=C#240. GOSUR $550 125 IF RNI(1 25.03.GOTO 12 130 N=85 : GOSUB 700135 N=38: GOSUR 780 140 PRINT\" GOSUB 565 141 REM ASTEROID STORM 142 DF-RND 0.9) GOTO. 150 144 FRINT WARNING MASTEROIL STARM-SHIELD DAMAGE 146 FOR N=117004 GOSUB 700 FORES 46NEXT 1 46 F=20914 N=BW=w*0.7 GOTO 155 49 REM THLTFTTHC. 159 REGN=INT RND(1KC 16. 155 SOR NEN TO 12: GOSUB 490 NEXT GOSUB 34 158 GOSUB 505 IF FHD (108.7 GOTU 150 159 REM SELECT COMMANDS 160 GOSUB 800 PRINT SCOMMAND26 GOSUB 960 185 IE TOE 36 GOTO 1661 173 IN O GOTO 240, 1900, 220,200 116,286 199 REM NEUTRON MISSILES 6 200 IF HUGOTOL.1900 261. HEHGOSUE 300: IF PEEK 48 BOT 206 364 FRINT SE TARGET NISSED-INCORRECT COORDINATES\":GOTO 150 326 GUSUB 3015: IF DC32 GOTO 210 ZG6 PRINT SEE THEGETI MISSED-OUT OR RANGE \":GOTO 150 219 TET-TOGOSUR 600: P=6 NEOGOTO 155 219 REM SHIELD CONTROL 3 220 GOSUB 800 EE+W: PRINT BENERGY\", INTCE), \"SHIELDS?\"; : GOSUB 900 223 W=0 E=EW IF EC1 GOTO 229 225 GOTO 160 229 REM PHASER CONTROL (4) + 230 GOSUB 800 PRINT\" SENERGY\" INTCE), \"PHASERS?\"; : GOSUB 990 233 PEQIF ECP OR PCO GOTO 230 235 E=E-PIN=G: GOTO 155 34 COMPUTER & VIDEO GAMES "


"Free 239 REM HELM CONTROL (1) 249 GOSUB 309: GOSUB 305: GOSUB 450 245 IF PEEK(X) 48 GOTO 255 246 PRINT\" SRSTARFIGHTER DOCKED-REFUELED AND REARMED 250 E=2600 W=499: H=85(35)=0: GOTO 256 255 IF PEEK(X) 32 GOTO 240 LC 256 POKE S(36), 32: S(36)=X: POKE X,87 GETU 1982 299 REM CO-ORDINATE SUEROUTINE 390 GOSUB 800: PRINT \"SCO-ORDINATESCYX)? GLISUB 999 : X=Q 301 X=X-60*INT (X/100)+32398 IF X33767 OR X32808 GOTO 300 303 RETURN 380RE DISTANCE SUBROUTINE 305 D=ITSUBCR328982491)-INT( Bene 310 D=ABS S(36448*DRESURFETURN 339 REM SET-UP TARGETS SBEROUTILE 345 FOR N=0 TO 19: POKE SCN).32 STN = NEXT 350 FOR N=0 TO 101: IF N=C THEN RETURN 360 GOSUB 780: NEXT 399 REM PHASER SUBROUTINE 400 IF CC1 THEN RETURN 495 IF PEEK(SON)43 THEN RETURN 410 X=S(N): GOSUB 305: D=D*C:IF P/DCT/C GOTO 415 T=T-T/C: PEP-P/C: GOSUB 600: RETURN 420 TOT-P/D:W=W-T/D: IF PC1 GOTO 423 421 GOSUB 750 : POKE X,43 423 X=S(36): GOSUB 750 : POKE X,87 425 IF W0 THEN RETURN 430 GOSUB 750 : POKE X, 32: W=0 435 PRINT\" MISSION FAILED-STARFIGHTER DESTROYED \"GOTO 1000 449 REM STARFIGHTER ENERGY SUBROUTINE 450 E=E-D: IF EX31 THEN RETOUR 455 FOR Q=@ TO 20: PRINT\" ENERGY DEVELS ORIDICAL REDUCE SHIELDS\":NEXT 460 IF EU THN RETURN 465 E=0: PRINT\" SMISSION FAILED-STARFIGHTER DEAD SPACE\":GOTO 1000 499 REM POKE CURRENT SECTOR 505 FOR N=0 TO 36 510 IF SHE THEN NEXT 515 IF N>10 HND <35 THEN POKE S(N), 42 520 IF NCIT THEN PEKERS(N), 43 525 IF N=35 THEN POKE 4 8 530 IF N=36 THEN POKE SONG 535 NEXT: RETURN 599 REM TARGET DESTROYED SUBROUTINE 600 D=5 GOSUB 750 POKE X.32:C=C-1 KERST 18 K GOT0 670 605 IF CC1 THEN RETURN 610 IF S(35)=0 GOTO 620 615 D=2 X=S(35): GOSUB 750 : POKE X, 32:5(35)=0 626 IF RND(1) <0.9 THEN RETURN 525 k=K+CC=2*C:T=2*T: RETURN 670 PRIT\"SMISSION COMPLETE-ALL TARGETS DESTROYED\" : GOTO 2000 699 REM RENDOM POSETION SUBROUTINE 700 SCN)=38858+INT980: RND(1)) RETURN 749 REM ANIMATION SUBROUTINE 750 FOR Q=0, TENGELD POKE X,86: POKE X, 42: POKE X,91 : NEXT: RETURN 800 PRINT\" \"RETURN 899 REM OPEN FIE UBROUTINE 900 OPEN 1.03 965 INPUT#1, 0 F Q$=\"\" THEN 995 310 QEVAL(Q$): CLOSE 1 : RETURN 999 PEM SCORE & NEW GAME 1000 FOR Q=0 TO 2000: NEXT: GOSUB 2000 1902 TM=VAL (LEFT$(TI$.4) ) +VAL(RIGHT$(TI$, 2))/60 1004 PRINT\" MUAYYOU SCORED\"; INT(<5-SOR(K))*(30-TM)); \"POINTS 1995 PRINT\" PRESS ANY KEY FOR ANOTHER GAME\" 1010 GET 0$: IF Q$=\"\" THEN 1910 1015 GOTO 90 1899 REM SCAN SUBROUTINE (2) 1900 GOSUB 2000 PRINT\" PRESS SPACE BAR OR 'I' FOR INSTRUCTIONS\" 1905 GET Q$: IF Q$=\" \" GOTO 1920 1910 IF QO\"I\" GOTO 1995 COMPUTER & VIDEO GAMES 35 "


"SEX AND YOUR COMPUTER??? THE NAUGHTY ONE SPECIAL FREE OFFER READ ON! VI$20 An adventure for Iveryl broadminded people Pay your way through gambling dens, bars and houses of vice, be secluded or seduced, earn a slave, acquire part of your opponents' bodies Loose your money and borrow. Tha..there is no bank, only a pawnbroker, whose sole collateral will be some of your clothesl Gamble for the clothes of your opponents. force the pawnbroker to auction some clothes (preferably from other players...), be given some saucy tasks or dole some out Build a massage parlour and bankrupt for undress) your opponents, if they are unlucky A mini version of this game is now available on cassette. The maxi version on disk is much more expanded and contains in between other things 40 pubs and bars, 20 gambling houses and also.. no, we won't tell. Play it safe (for tokens) or play it hard. If you dare, that is... A SPHINX COMPUTER GAME THE FIRST FULL FEATURED COLOUR COMPUTER AT UNDER !! 1620 xava NM THE SIGN OF HADRIN Become familiar with dark age Britain and dig your way to a ,000 treasure which is actually buried in this country A game which will tax the highest intelligence and needs real application to find the solutions It also includes a lot of outside activities. Follow the trail of this dark age magician and discover his tomb, with the real treasure in it A SPHINX COMPUTER GAME GOLD Find your way to more than forty rooms, collect the treasures and try to get out with them Very addictive. With the game come instructions on how to win a Memotech Memory Expansion On the same tape: Pick a Word, a game of skill Try and beat your children at it A HILDERBAY GAME FEATURES *Sound \"Colour *5K Memory Expandable to 27K *Standard PET Basic Full size typewriter Keyboard Graphics Plug-in memory expansion \"Low-priced peripherals. THE FOLLOWING ITEMS NOW AVAILABLE CODE: VICI VIC 20 computer at .99 incl. VAT VICII VIC cassette unit at .95 incl. VAT VIC III VIC 3K RAM cartridge at .95 incl. VAT VIC IV VIC 8K RAM cartridge at .95 incl. VAT VIC V VIC 16K RAM cartridge at .95 incl. VAT ARFI Arfon Expansion Unit at .75 incl. VAT SPECIAL FREE OFFER 3K RAM CARTRIDGE WITH EVERY VIC 20 COMPUTER ORDERED PLUS FREE GAMES TAPE WITH EVERY CASSETTE UNIT ORDERED. Offer Ends April 30th 1982 437 Stoney Stanton Road, Coventry, CV6 SEA West Midlands Tel: (0203) 86449 SYSTEMS THE MAZE GAME Go through three dimensional mazes which are unmapped and find your way about The game cannot become boring because the mazes change all the time. If you are a maze addict A SPHINX COMPUTER GAME GOLF A step nearer to the real thing Played on actually existing courses, with a full selection of clubs. Contains all the necessary like weather, wind, and other atmospheric circumstances. You control yourself whether you slice or hook and you also determine yourself the impact on the ball Available in March with full colour graphics A SPHINX COMPUTER GAME THE SECRET CODES Not a mastermind type of game at all There are many coded texts on the disk (or cassettel which may be very difficult to decipher We undertake to pay .00 to the sender of the first complete listing of all the texts, listing which must be faultless of course Sample? HOGARIM MESHA STWAND TARAGHON MOTASHIN SOMETIMES DRASHTIM MEGRAHON SHARDSOMSH KRIDNAHAM A SPHINX COMPUTER GAME ORDER FORM GAME TITLE Cassette (16 ) | | | | THE NAUGHTY ONE mini version 9.50 9.50 THE NAUGHTY ONE (maxi version) THE SIGN OF HADRIN THE SECRET CODES 8.50 8.50 THE MAZE GAME 8.50 8.50 GOLD (A Hilderbay Game) 8.00 GOLF favailable March) Circle items wanted IBEK TSOT VICI ,99 + .45 P & P VIC II .95 +  P & PO VIC III .95 +  P & P O VIC IV .95 +  P&P VIC V .95 +  P & P D ARF | .75 +  P&P diskette (48K) Atari Apple il Name: ......... Address: ............... 24.5024.50 29.50 29.50 12.00 12.00 12.00 12.00 12.00 12.00 29.50 29.50 Please charge my Barclaycard Access No. 000000000000000 Name Address Signed: .... Or telephone order Town. Postal Code Remittance enclosed. V.A.T. is included. Please add 50p for PSP if order less than .00 Send to HOLDCO LTD. 14 BRITTON STREET LONDON EC1M 5NQ 36 COMPUTER & VIDEO GAMES "


"1915 GOSUB 5000 1926 PRINTO\" GOTO 158 2000 PRINT\" DATASCAN STARDATE \";TI$ 2005 PRINT\" ENERGY, INTCE)\" SHIELDS\" INTCW)\" MISSILES 2015 PRINT\" TARGETS: CURRENT SECTOR\" C\" TOTAL\";K;\"X\" 2050 IF W<1 GOTO 2056 2953 N=36 GOSUB 3050 2055 PRINT\"STARFIGHTER POSITION\"X;\"#\" 2056 IF S(35)=0 GOTO 2060 2952 X=S(35): GOSUB 305: N=35: GOSUB 3850 2958 PRINT\"STARBASE POSITION=\";X RANGE\";D;\"0\" 2060 Q=100: IF C=0 THEN RETURNS 2070 FOR NEO TO C-1: GOSUB 3000: NEXT 2975 PRINT \"OMINIMUM PHASER ENERGY\" INTCT*Q+0.9);RETURN 3000 X=9(M) GOSUB 365 GOSUB 3050 3005 PRINT \"TARGET POSITION \"X\" RANGE\":D 3010 IF QD THEN Q=D 3015 RETURN 3050 K=60#INTCCS(N)-32408)/40) +SXN)-32398: RETURN 5000 PRINT\" STARFIGHTER-COMMANDS 5016 PRINT\"1 HELM 5015 PRINT\" MOVES STARFIGHTER IN CURRENT SECTOR 5020 PRINT\"2 SCAN 8 5025 PRINT\" GIVES CURRENT STATUS AND CO-ORDINATES 5030 PRINT\"3 SHIELDS 5035 PRINT\" DEBITS OR CREDITS ENERGY IN MAIN BANK 5040 PRINT\"4 PHASERS 5945 PRINT\" ENERGY WEAPON, THE EFFECT IS DIVIDED 5050 PRINT\" BETWEEN TARGETS IN CURRENT SECTOR 52 5060 PRINT\" AND BY DISTANCE. THE RESULT IS TAKEN 5065 PRINT\" FROM THE TARGET'S ENERGY BANK. ANY 5070 PRINT\" TARGETS LEFT IN THE SECTOR ATTACK 5080 PRINT USING THE SAME PROCEDURE. 5085 PRINT\" EACH TARGET'S PHASER ENERGY IS 240 5090 PRINT\"5 NEW SECTOR 5995 PRINT\" MOVES STARFIGHTER TO NEW SECTOR AND 5100 PRINT\" DEBITS 31 FROM MAIN ENERGY BANK 5105 PRINTYS NEUTRON MISSILES E 5110 PRINT\" DESTROYS BY A SINGLE SHOT. DIRECTION 5115 PRINT AS HELM. MAXIMUM RANGE 31. TARGETS 5120 PRINT\" LEFT IN THE SECTOR ATTACK AS IN 4 13 5125 FRINT\" PRESS SPACE BAR 5130 GET Q: IF Q$0\" \" GOTO 5130 5135 PRINT\" SIASTARFIGHTER-NOTES: 5140 PRINT \"A. THE GRID IS 24848, Y CO-ORDINATES RUN 5145 PRINT\" 10 TO 33 AND X CO-ORDINATES 10 TO 49 5150 PRINTB. IN HELM OR SCAN TARGETS ATTACK AND 5155 PRINT\" OR MOVE AT RANDOM 5160 PRINT\"C. IN ATTACK TARGETS MOVE AND MAY ENTER 5165 PRINT\" THE SECTOR AT RANDOM. TARGETS LEFT 5170 PRINT\" ALSO DESTROY STARBASES 5175 PRINT\"D. ALL MOVES REDUCE ENERGY S180 PRINT'E. TO REFUEL HELM ONTO STARBASE (ONCE 5185 PRINT\" ONLY PER STARBASE) 5190 PRINT\"F. ASTEROID STORMS REDUCE SHIELDS BY 5195 PRINT\" AT LEAST 30% AND DAMAGE OR DESTROY 5197 PRINT\" TARGETS AND STARBASES. 5200 PRINT\"G. DISTANCE IS THE SUM OF .X AND Y 5295 PRINT\"H. STARFIGHTER: O TARGET: + STARBASE: 0 5219 PRINT\"I. SCORE IS A FUNCTION OF TIME & NUMBER 5214 PRINT\" OF TARGETS LEFT. (STARDATE=TIME) 5215 PRINT\" PRESS SPACE BAR 5220 GET Q$: IF Q$ \" \" GOTO 5220 5225 PRINT\"9\" : RETURN READY. COMPUTER & VIDEO GAMES 37 "


"KRIEGSPIEL Wargamers have long realised that computers would add a lot to their hobby. BY RON POTKIN When the ranks of carefully painted warriors have been moved into their starting positions, the game proper gets RUNS ON A TANDY TRS-80 IN 16K underway only through some persistant dice throwing and careful consideration of tables. The microcomputer can make short work of these leaving Each must be oriented left or Before getting involved in the right so squares and oblongs are detailed programming, you the general free to concentrate on his tactics. And although out. should understand the overall the game is certainly not as picturesque, it does mean that Keyboard characters are operation of the program. There wargamers without the necessary patience to spend time unrealistic. When playing, one are four arrays which control all building up and decorating their armies. should be totally involved and movement and attack, these are: Ron Potkin's Kriegspiel is based on a Second World War feel as though the battle is really Video screen: run the program tank battle and has become an extremely popular game on happening: I am afraid the letter and put the hex board on the the Tandy. We'll leave it to Ron to tell you a bit more about \"A\" for army does not turn me screen. Each hex is numbered the game. on. according to its first \"print O\" position. The top left-hand hex is number 4. The next is number 12 I finally determined that four and so on up to 60 in steps of 8. battle and not be tied down to bytes were required to build up a The second line runs from 64 rolling dice and consulting neat shape and meet all my to 120. Note that alternate rows charts. The TRS-80 has changed requirements. After allowing for are offset by four so that the About three years ago all that. Think of the advantages: a line of messages and spaces hexes fit together. The same bought several boxes of those It determines when conflict between the pieces. I had a format continues down to hex small one-inch high plastic should occur and the nature of board of about 120 hex. In number 956 leaving the bottom soldiers. They represented the the conflict. Kreigspiel II, have adopted a line for messages. Let's look at a French and British from the rolls the dice and resolves different approach so that it is section of the screen using hex Battle of Waterloo. In all there all combat between opposing possible to have 500 hex. number 400 as an example. Now must have been 400-500 pieces. sides. I think you will enjoy the game. deduct 400 from every number to The next three months were it is an impartial referee and it My son Leigh, and I have played arrive at the offsets. If we know spent painting the detail on each will not tolerate heavy breathing it many times and have the direction. These enable us to piece using a magnifying glass, or that gasp of relief that moves developed our own personal move a piece from one hex to but after the first 100 regreta complete armour division strategies. Invariably, one another. We could calculate that my enthusiasm began to across the Mediterranean scenario becomes particularly them but it is faster to use \"on wane. There is no doubt that the Real hidden movements is interesting and we play it over direction-goto\" (line 21500). As sight of several hundred warriors possible. No longer does one and over. an alternative a table of values lined up for battle is very appeal need to write down on a piece of Kriegspiel is a further could be used. ing but I felt there had to be an paper the current location of development of this game with Piece table \"PC\": This is a 32 easier way each hidden piece. more preces, minefields, by 6 array and contains details of All this occurred about 12 It was with these points in weather, recruiting, a larger the 16 pieces on each side. The months before the Birth of the mind that I wrote Kriegspiel. board and other features, but the first column is the current hex Byte.\" I had played several comWhile designing the game. I same basic strategies apply. number position on the screen. mercial wargames and although had to consider: I am not going to give any The second contains the type of they were very interesting, there The minimum size of hex. advice on tactics other than to piece-tank, infantry, engineer or was a lack of realism because the shape of each piece. urge you to study the table of capital. The other four columns felt that a General should be the necessity to be able to odds very carefully before you contain combat pointers which allowed to concentrate on the distinguish pieces on each side. attack will be described later. When a 38 COMPUTER & VIDEO GAMES "


"piece is eliminated, column 1 is 2. Turns are determined by \"5\" COMBATI Lines 1750 to 2500 carry out set to zero. in line 1000 which sets the varithe results of the combat result The board \"BO\": This is a 16 able 1, to either 1 or 17 indicating SEQUENCE \"R\" as follows: by 16 array, including the zero the index of the first piece to be 1. Exchange: index and is an internal represen moved. Lines 1305 to 1500 are a The defender is automatically tation of the map. Each indexed 3. Gets the hex number FL, the prompting routine and settle all eliminated (line 24000) but a test position is equal to one hex on number of moves \"MV,\" and the attacks. Note that the use of the must be made to check how the screen. Each vacant position character \"FL$.\" (lines 1010, flag 22\". This is set to one if an many factors the attacker had on the screen is set to zero on 1020). attack is found. If it is zero at line (line 1706/7). If they were less or the board. An occupied position 4. Prompt for a decision by 1550, it means there are no equal to the defender's, then contains the index of that piece flickering \"FL$\" and \"MV.\" (line attacks and the combat elimination is automatic. Otherin the piece table. Positions 1030). sequence is finished. wise the attacker is prompted for occupied by mountains contain 5. If the input is a number, Lines 1600 to 1745 are more the pieces to be eliminated. -1, -2, or -3 according to the type check if valid and either move the complex. They are concerned 2. Attacker Eliminated of mountain. piece or continue prompting with determining which pieces This is automatid and all Characters \"PC$\". This is a 7 (lines 1050-1210). are involved in each individual attackers are eliminated using by 4 character string holding the 6. Checks during movement combat, whether the defender the routine at line 25000 shapes to be printed on the line 1065) for the winning condihas support; whether the attack 3. Defender Eliminated screen. The correct character is tion. is across the river; and finally This is automatic and the obtained by means of its index in 7. Line 1075 checks \"river selecting a random result from defender is eliminated using the the second column of the piece crossing,\" If this is true, an extra the attack table. routine at line 24000. table, movement factor is deducted. A defender table \"DR, is set 4. Defender Retreats: It will be apparent that, using 8. Line 1182 checks one hex in up. This holds details of each The player is prompted for the the information in each of the every direction using \"Search\" defender as it is found in the direction of retreat and a check is arrays, we can easily move from looking for an opponent. piece table (line 1620). The made for legality. If there is no one table to another. There is attacker is put in the attacker's retreat then an \"E\" is typed and one missing link. This is the contable \"0\" (lines 1680-1690). We the piece is eliminated. The varinow go through the rest of the able \"RD\" is 7 count of the piece table searching for any number of hexes moved. other pieces attacking the same Remember that the defender is defender. These are added to the now allowed to move next to an \"Q\" table. As each is added, the opponent. attack factor \"AT\" is increased 5. Attacker Retreats: (and increased again if the This is essentially the same as attacker is a tank), the river \"Defender Retreats\" except, of crossing flag is \"and\" ED with course, that all attackers must \"DR(3)\" and column 3 of the retreat. The program now piece table negated so that piece returns to line 1600 to look for 9. Intermingled in the coding is cannot be involved in another further combat. Exit back to the the Hold routine. Follow this attack. main routine via the return in line version from the hex number to through watching the variables Lines 1700-1710 calculate the 1610. the board coordinates which is \"HD,\" \"K1,\" and \"HL\" in lines defender's factors and go to the The following is a list of the carried out in line 2100: 1000, 1010, 1017/8, 1047/8, and subroutine at 4000/4200 to check variables used in the program: Y1=INT(P/64) 1218 for support. X1 SP-64.Y1/4 10. The \"C\" \"S\" and \"F\" Lines 1720-1740 calculate the (Where \"p\" is the hex commands are easier to follow.attack ratio and find the appronumber) but note that \"C\" jumps immedipriate column in the attack table Much of the program is conately to line 1300, whereas \"F\" from which it selects a random direction indicator cerned with the manipulation of carries out a full check of pieces result. If you are like me, you input from keyboard these arrays. It is in motion by that have not been prompted to probably find typing the rules is PAD\" defender support putting the initial hex position of check for possible attacks. Since drudgery, so if you want to see factors. each piece in each array and then this involves checking six hexes the attack table, look at lines \"AF\" attack ratio running through the piece table for every piece, it is a slow pro20162-20167. Now read through \"AJ\" piece in adjacent prompting for a decision on each cess and therefore, if it can be lines 40192-40415 which tell you hex. hex. piece in turn. Assuming the piece seen that no pieces are adjacent, the outcome for each value in the attack factors. is on hex 400 and you type direcit is better to use \"C\" table. \"AT\" plus 50% tion 6, the program calculates the Let us take stock of what we Note the use of the flag \"RV\",\" temporary variable. board coordinates, checks that have when we finally reach line which indicates whether the \"B$ temporary keyboard hex 352 is vacant and, if it is, 1300 the start of the attack attack is across the river. The input moves the piece. sequence: rules state that the defence fac\"B1 piece index in It now checks the six hexes 1. The board, video, and piece tor is doubled unless the adjacent hex surrounding the new hex to see table have been updated in defender is also being attacked \"B2\" used during whether it is next to an op. respect to all movement. on the same side, of the river. Initialisation ponent. One side has indices 1 to 2. Mountains will have been Put simply, this means that if the \"BD\" internal board 16; the other 17 to 32: So if piece adjusted on the board and video river flags of all attackers (colCL\" used in calculating 12 (less than 17) is next to piece when they have been eaten awayumn 6 of the piece table) are set, attack result. 24 (greater than 16), an attack by the engineer. then the attack is across the \"CT\" temporary variable, takes place and any further 3 Columns 3, 4, 5, and 6 of the river. If any flag is not set then all \"DF\" defender's factors movement ceases. piece table contain information others are nullified and the (including support) The following is an outline of regarding attacks. Note that if defence is not doubled. This \"DR\"defender pointers the movement sequence: column 4 is set to one that attack result is very easily obtained by \"D\" defender's factors. 1. Line 200 controls the whole will be automatic and requires no using the \"And\" instruction and \"EX\" used in exchange to game. At the end of a player's prompting. If it is greater than what at first appears extremely ensure that enough turn, the program returns here then a decision is required by the complex is resolved in a single attackers are and changes sides. player. instruction! removed. A ASUM COMPUTER & VIDEO GAMES 39 "


"\"K1\" \"RT\" \"RV\" — save \"X1\" \"S\" \"SD\" \"FLS \"SE\" MT\" \"MV\" \"P\" \"F2\" attack flag \"F3\" flag used when looking for support. current hex number. current piece character. pointer to current attacker when looking for defenders in combat sequence. \"HB\" maintains count of attackers in table \"Q\". \"HC\" temporary count. \"HD\" \"hold\" variable \"HL \"hold\" variable. \"HX$ hex board request. \"1\" index to piece being moved. \"J\" temporary variable. \"K\" temporary variable. \"PC\" \"PCS \"hold\" variable. used to save pointer. used to create river. used for prompt messages. number of mountains. moves left. new hex number. piece table. piece characters. table of attackers. used in random number generator. hex board. hex board. hex board. used in random number generator. hex board. retreat count. random number. attack result. \"X2\" river crossing flag. \"Y\" see \"X\" whose turn is it? see \"Y1.\" random number \"Y2\" see \"X2.\" seed. \"Z\" hex offset. holds \"SD.\" This is \"ZZ\" attack flag necessary since the hope you will enjoy this pronumber of mountains gram and maybe, with the help requested could of this explanation, find ways to upset the shape of improve it. I adopted most of the the river. The river ideas in this game in Kriegspiel II can't be placed first but the programming methods because it would be changed in several instances. For destroyed by the example, I found that many mountains. routines particularly \"search used to create river. and \"river crossing\") could be table of attack simplified by using tables of data. outcomes. Probably the best change I made coordinates to river however was to surround the graphics to check for board with a boarder of 99s. This river. greatly simplified checking for hex number to board movement off the edge of the coordinates. board. \"R1\" \"SR\" \"TB\" \"R1$\"R25 = \"R3$\" \"R3\" \"R4$ \"RD\" \"RN\" De Ach a tooth CLS:PRINT0143,\"111111111111111111111111111111111';: PRINTO207, KRIEGSPIEL :PRINT0271,' A WARGAME FOR TWO PLAYERS :PRINTI335,\" 1 B Y RON POTKIN 2 PRINT2399,111111111111111111111111111111111 3 CLEAR290: DEFINTA-Q,T-Z: RANDOM 5 DIMPC (32,6), TB(6,11),BD (15,15) 6 GOSUB20000:CLS 10 INPUT DO YOU WANT THE RULES\";BS:IFLEFTS(B5,1)=\"YTHENGOSUB400 00 13 INPUT DO YOU WANT A HEX BOARD\";AXS: IFHXS=\"Y\"THENRV$=\"N\" 14 PRINT\"SET YOUR SCENARIOS: INPUT\"HOW MANY MOUNTAINS (OT025) \";MT : IFHX$=\"N'THENINPUT DO YOU WANT A RIVER\":RVS 16 IF (NT>O) DR (RVS)'N' THENINPUT\"ENTER THE SCENARIO NUMBER\";SD:S DESD1.528416: SE=SD 100 CLS:60SUB20450:S=17: IFRND (2)=15-1 200 GOSUB1000:S=18-5:60T0200 1000 A$=INKEYS: A$=\"*:PRINT2960,\"1.. MOVE SEQUENCE\" :: I=S: HD=0: HL= 1005 FORKI=1T032:PC(K1, 3) =0: PC(1,4)=0: NEXTKI 1010 MV=3-21(I< (5+7));K1=ABS (PC(1, 1)): IFPC(1,1)=OTHEN1200 1017 IFHLEOTHEN1020 1018 IFPC(1, 1) >OTHEN1200ELSEPC(1,1)=-PC(1,1):HD-HD-1 1020 IFPC(1,3)<>O THEN 1200EL SEFL=PC(1,1):FLS=PCS (PC(1,2)) 1022 IFAS=\"F' THEN 1182 1025 MSS=STRS (MV) 1028 PRINT 980,\";IFI=STHENPRINT ENGINEER'; EL SEIFIC (S+7) THENPRI NT'TANKELSEPRINTS INFANTRY\"; 1029 PRINTSTRS 11);:R451-100 INT(1/10);IF(1310) ANDIK(21) THENPRINT TH\"; ELSE IFR4=1THENPRINT ST\";EL SEIFR4=2THENPRINT'ND\"; ELSE IFR4=3TH ENPRINTERD\"; ELSEPRINT TH\"; 1030 GOSUB 23000 1040 IFAS=\"S' THEN 1182 1045 IFAS=\"F' THENFORKESTOS+14:PC (K,1)=ABS (PC (K, 1)): NEXTK: HL=0:H D=0:6070 1182 1047 IFA8=\"HTHENIFKI<>PC(1, 1) THEN1030EL SEIF (PDXI, 1) >0) THENPCI, 1)=-PCII, HD-HD+1:60T01200 1048 IFAS=\"C\" THEN FORK=STOS+14: PC (K,1)=ABS (PCIK, 1)): NEXTK:HL=0; HD=0:PRINT2980, STRINGS (12, 9;: 60T01300 1050 A=VALTAS): IF(A(1) OR (A) THEN 1030 1060 GOSUB 21500 1065 IF (S-17) AND (P=200)) OR ((S-1) AND (P=820) THEN 30000 1067 12=X1: Y2=Y1:60SUB 31075:Y1=Y2:X1=X2: IFAJK)-2THEN1070ELSE TFRUTHENPRINT01000, \"MOUNTAIN ACROSS RIVER\":FORK=1T01000: NEXTK:P RINT01000, STRINGS (22,' ');60T0 1030 1068 MV=1:BD(81,1)=BD (Y1, X1)+1: IFBD (Y1, X1)<>OTHENPRINTOP, MTS-B D(81, XIX): GOT01182EL SEGOSUB21010:IFY>1THENRESET 1X+2,Y-2): RESET I+5,Y-2) 1069 PRINTOP, \": RESET (X+2, Y+2): RESET (X+5,Y+2):6OTO 1182 1070 IFAJ( 0 THEN 1030 1075 IFMV=1 ANDRVTHEN1030EL SEMV=MV+ (RV=1) 1170 PRINTOFL,. ';:PRINTOP, FLS; 1175 GOSUB 21000 1180 PC(1,1)=P:BD (91, X1) = 1:P-FL: GOSUB 21000: BD (Y1, X1)=O: FL=FL+2 1182 FORA=1T06:60SUB21500:60SUB22000: NEXTA 1189 IFA$=\"S'ORAS=\"F\"THEN1200 1190 MV=MV-1: IFMVTHEN1020 1200 PRINT2980, STRINGS (15,' ');:1=1+1) IFK< (5+15) THEN 1010 1210 IFHD>OTHENHL=1:I=S: 60101010 1300 PRINT3960, 2.COMBAT SEQUENCE\"; STRINGS (45, 1305 17=0 1310 FORI-STOS+14 1315 IF (PC(1, 3) =0) THEN1500 1318 72=1 1320 IF (PC(1,4)=1) THEN1500EL SEFL=PC (1,1) FLS-PCS (PC(1,2)) 1325 MSS=\"AT\" 1330 60SUB23000 1340 A=VAL (AS) IFA=(A1) OR(A) THEN1330 1350 GOSUB21500 1370 GOSUB22000 1380 IFF2=060T01330 1500 NEXTI 1550 IFZZ=ORETURN 1600 AT=0: HA=S:HB=0 1610 IFPC (HA, 3)(=OTHENHA-HA+1: IFHA(+14) THENRETURNEL SEGOT01610 1620 DR (1) =PC CHA,3): DR(2) =PC (HA,5): DR (3)=POCHA,6) 1630 GOSUB1680 1640 HA-HA+1: IFHA? (S+14) THEN1700 OF 40 COMPUTER & VIDEO GAMES "


"SPECIAL ANNOUNCEMENT FOR ESOAVERSOS ATARI OWNERS NETWORK COMPUTERSOFT PRESENTS personal computer software A NEW CONCEPT IN COMPUTER MAGAZINES NETWORK THE MEDIA MAGAZINE CASSETTE TAPE .50 16K/ZX 81 SOFTWARE \"STARTREK\" 16K STAR TREK: Exciting space adventure game including klingon, starbases, phasors, 8X8 galaxy, etc. \"SUPER-WUMPUS\" 16K SUPER-WUMPUS: Can you hunt and catch the mysterious wumpus in his underground labyrinth? Intriguing underground adventure. \"GRAPHIC GOLF\" 16K GRAPHIC GOLF: Test your golfing skills on SILVERSOFT'S 18-hole golf course. Many hazards including lakes, trees, streams, rough, etc. \"3D-MYSTERY 16K 3D MYSTERY MAZE: Amazing three dimensional maze, uses fast mc display, hundreds of different mazes. \"GAMES PACK 1\" 16K GAMES PACK 1: Fantastic value for money, nearly 50K of programs on one cassette. Five games including \"Real Time Graphic\" Lunar Lander, Starwars, Hammurabi, Minefield, Mastermind. Price .95 per cassette .95 for any two Coming soon Arcade Games Send S.A.E. for catalogue SILVERSOFT (Dept CVG) 40 Empress Avenue, Ilford, Essex. p&p included Join all ATARI owners with this exciting new cassette Magazine, Send coupon today for NETWORK No 1 PERSONAL COMPUTER SYSTEMS MICROCOMPUTERS ATARI ATARI 400 & 800 A MAGAZINE A USER GROUP PROGRAMME EXCHANGE NETWORK is a new idea in computer Magazines, comprehensive, colour graphics programme for all Atari 400/800 users with 410 recorders. Featuring: Computer C.B.; New product information; The puzzler'; Switch and Swap: details of discounts for subscription holders; Your letters and much more... Including a FREE, exciting graphics game sampler 'HOT-FOOT'. NETWORK is on a C30 cassette tape for ATARI 400/800 computers (16K minimum). Also available for the ATARI 400/800: NEW!! K-RAZY SHOOT-OUT The latest CARTRIDGE received from the USA A MUST FOR AL 400 800 OWNERS Prices include VAT K-RAZY SHOOT-OUT CARTRIDGE .95 An exciting fast action game. Eliminate the alien robots and escape. IF YOU CAN!! GALACTIC CHASE 16K Cass .95 as below) GALACTIC CHASE 16K Disk .95 A fast moving invader game with great sound and graphics GHOST HUNTER 16K Cass .50 All action MAZE GAME with two player option and Ghost hide function. A really compelling game. GIANT SLALOM 16K Cass .99 Ski down the slopes in your own home. Great fun for all. CHARACTER GENERATOR 16K Cass .50 Design your own characters and create games yourself with ease. A very useful utility programme. TEXT WIZARD 32K Disk .50 A comprehensive word processor, use your ATARI to produce letters and reports Easy to use, includes: Expanded print option, underlining. search and replace etc.. Please reply to: Dept CVG 1 COMPUTERSOFT LTD Administration Office 5 Watkin Road, Wembley Middlesex ATARI FREE! HOT FOOT IN MANCHESTER Air Strike 16K cassette .95 Galactic Chase 16K cassette .95 Crypt of Terror 16K cassette .86 * SOFTWARE * Ghost Hunter 16K cassette 1945 inc VAT * COMPUTER CHESS GAMES www BARCLACARD VISA N NNN MANCHESTER'S A TAR BEST ATARI DEALER JATARI YOUSSE ONTG CUR NIWATANZ VIDEO COMPUTER SYSTEM SPECIAL MAN ORDER ACTIVISION SERVICE WRITE OR PHOME FOR FULL DETAILS Please reply to: Dept.CVG 1 Administration Office, 5 Watkin Road, Wembley, Middlesex Please supply me: with the following: state number required name and address & remittance. Qty NETWORK MAGAZINE @ 4.50 p&p included But with @ @ @ @ @ @ Add 55p p&p ammador VIR PLUS GAMES NOW IN mamuvum Commodore VIC STOCK! GEMINI ELECTRONICS Dept.cvG, 50 Newton St.,Off Piccadilly, Manchester M1 2EA. Tel: 061-236 3083. WE ARE AT THE CORNER NEWTON ST./ HILTON ST. I enclose cheque/postal order TOTAL  Imade payable to Computersoft Ltd.) Name (print clearly). Address "


"1650 IFPCHA, 3) < >DR (1) THEN1640 1660 GOSUB 1680 1670 60101640 1680 HB-HB+1:0THB, 1) =PC (HA, 1):Q (HB, 2) =HA: ATEAT+1: DR (3)=PR (3)ANDPC (HA, 6):PC (HA, 3)=-PC(HA, 3) 1685 IF (PC CHA, 2) ) OR (PC (HA,2)=5) THENATEAT+1 1690 RETURN 1700 DT=1 1710 IF (PC (DR(2),2)=2) OR (PC (DR(2),2)=5) THEN DT=PT+1 1712 60SUB4000 1715 IFDR (3)< >0 THEN DEEDTADT 1720 AX-INTYAT+.51AT): IFAX (DT+AD) THEN AF SINT (AX/(DT+AD) ): DF=1: CL-AF+5:50T0 1740 1730 DF=INT (DT+ADTAX): AF=1:CL=7-DF 1740 IFAF6 THEN RTE1 EL SEIFDF6 THEN RT=-1ELSERT-TB (RND (6),CL) 1745 PRINT0980, \"ATTACKER\";AX; \"DEFENDER\";DT+AD; 1750 IFRTO THEN 1900 1755 PRINT\" EXCHANGE\"; 1770 GOSUB 24000 1780 HA=1 1785 IFHB=1 THEN GOSUB 25000:60T0 1900 1786 K=O:FORHA=1TOHB:K-K+1: IF (PCHA, 27, 2) =2) DR (PC(QCHA,21,2)=5 THENK=k+1 1787 NEITHA: IFK(=PTTHENFORHA=1 TOHB:BOSUB25000: NEXTHA: 60T01900 1790 HA=1:EX=DT:CT=HB 1795 IFO CHA,1)=0 THEN1880 1800 MSS=\"EL\":FL=PC(QCHA, 2), 1):FLS=PCS (PC (CHA, 2),2)) 1810 GOSUB 23000 2045 KP=FL:FLAR: A=1 2050 GOSUB 21500:1FAJKO THEN 2070 2055 IFPEKP THEN 2070 2000 IF ((5=17) AND CAJE) AND (ALC7110R (5=1 AND (AKAND (AJ>01) THEN FLEKP:SOT02020 2070.A-A1: JFAK7 THEN 2050 2075 P=FL:FL-KP:PRINTOFL,' ';:PRINTOP, FLSDR (1) =P:PC(DR(2), 1 1 =P:GOSUB 21000:BD (Y1, X1) =DR (2):P=FL: GOSUB 21000: BD1Y1, X11=0 2080 RD=RD+1: IFRD=2 THEN 2018 2100 IFRT=-2 THEN PRINT\"ATTACKER RETREATS 2\"; ELSEBOTO 2500 2110 FORHA=1 TOHB 2115 RD=1 2120 MSS=\"RT\":FL-PC(QCHA,2),1):FLS-PC (PCOQCHA,2),2)) 2130 GOSUB 23000 2140 IFAS=\"E' THEN GOSUB 25000:60T0 2195 2145 A=VAL (AS): IF (A1) OR (A) THEN 2130 2150 GOSUB 21500 2155 IFAN<>O THEN 2130 2160 KP-FL:FL=P:A=1 2165 GOSUB 21500: IFAJCO THEN 2185 2170 IFP=KP THEN 2185 2175 IF4517) AND ((AJ+2) OR (AJ=3) OR (AJ=11) THENFLXP:60T02130 2180 IF (S-1) AND AJ=4) OR (AJ+5) OR (AJ=6)) THENFLEKP:60T02130 2185 A=A+1:IFA47THEN2165 2190 P=FL:FLEKP:PRINTOFL,' ';:PRINTOP,FL$; : CHA,1)=P:PC (QCHA, 2), 1) =P: GOSUB 21000:BD (91, X1)=Q (HA, 2):P-FL:GOSUR 21000: BD (Y1/11) 20 2192 RD=RD+1: IFRD-2 THEN 2120 2195 NEXT HA NA AN 1B20 IFAS=\"E\" THEN 1850 1830 IFA$=\"X' THEN 1880 1840 GOTO 1810 1850 GOSUB 25000 1860 Q (HA,1)=0 1865 CT-CT-1: IFCT=0 THEN 1900 1870 IFEX<=0 THEN 1900 1880 HA-HA+1: IFHA (HB+1) THEN 1795 1890 IFEX THEN 1790 1900 1910 IFABS (RT)(>1 THEN 2000 1920 IFRT--1 THEN PRINT'ATTACKER ELIMINATED\"; ELSESOTO 1950 1930 FORHA=1 TOHB: GOSUB 25000: NEXT 1940 GOTO 2000 1950 PRINT\" DEFENDER ELIMINATED\"; 1960 GOSUB 24000 2000 IFRT=2 THEN PRINT DEFENDER RETREATS 2', EL SEGOTO 2100 2005 RDL 2010 MSS=\"RT\":FL=PC (DR(2),1): FLS=PCS (PC (DR(2), 2)) ,2020 GOSUB 23000 2030 IFAS=\"E\" THEN GOSUB 24000:60T0 2100 2035 A-VAL (AS): IF (A1) OR (A7) THEN 2020 2040 GOSUB 21500: IFAJ 0 THEN 2020 2500 FORK=110500: NEXTK:PRINT2980, STRINGS (42, \");BOTO 1600 4000 CHECK FOR DEFENDER SUPPORT 4010 AD=0:FORBITOHB:FL-Q18,13 4020 FORA=1 TO 6: BOSUB21500 4040 IF (AJ<=0) OR (AJ=7) OR ((S-17) AND (AJ)3) OR (S-1) AND (AJ<41) THEX4 200 4055 IFPC(B1,3)=1 THEN4200 4060 F3=0:FORI ESTOS+14 4070 F3=0:FORI=STOS+14:F3-F3-TABS (PC (1, 3))=P) 4075 NEXTI 4080 IFF3=OTHENAD=AD+1: PC(B1,3)=1: IF (AJ=2) OR (AJ+5) THENAD=AD+ 4200 NEXTA, BE RETURN 20000 DATA1,516 20060 DATA2,576, 456, 276, 156, 208,328 20080 DATA3, 216, 336, 396,268,140, 80,260,320 20100 DATA7,200 20110 DATA4,504 20120 DATAS, 444,564,744,864,692,B12 20140 DATA6,804,624,684,752,700,760,880,940 20150 DATA7,820 20160 DATA-1 20162 DATA-1,-1,-2,-2, 2, 1, 1,1,1,1,1 20163 DATA-1,-1,-1,-2,0,0,0,0,0,2,2 20164 DATA-2,-2,-2,-2,-2, 2, 2, 2,1,1,1 20165 DATA-1, -2,-2,-2,-2, -2, -2, 2,2,2,1 20166 DATA-1,-1,-1,-1,-1,-1, 0, 0,2,1,1 20167 DATA-1,-1,-1,-1,-1,-1,-1, 1,1,1,1 42 COMPUTER & VIDEO GAMES "


"20180 1=1 21600 IF(X1ANDI)=YANDIMOR (Y1>14) OR (YKO) THEN AJ=-1: RETURN 20200 READY: IF (XO) THEN 20262 21610 BIEBD (Y1, X1) 20220 IF (XB) THEN Y=X: 60TO 20200 21615 IFB1<0 THENIFTS THEN AJ=-1: RETURNELSEAJ--2: RETURN 20240 PC(1,1)=1: PC(1,2)=Y 21620 IFB1< >OTHENAJ=PC(B1,2) 20260 1=1+1:60 TO 20200 21630 RETURN 20262 FORT=1T032:P=PC11, 1), SUB21000:BD (YI, X1)=1: NEXTI 22000 GOSUB34000: IFF2=ORE TURNELSE: PC (1, 3) =P: PC41, 4) =PC (1,4) +1: PC 20265 FORI=1T06:FORJ=17011: READTB(1, JI NEIT J, 1 (1,5) =B1:F2=1OSUB 31075: PC(1,6)=RY 20280 PCS (2) CARS (183)+CHR$(187)+CHRS (132) 22005 PRINT1000,\"ATTACK, IFRVI THEN PRINT\" ACROSS RIVER\"; 20290 PPS (U +CHR$(157)+CHR$(140) +CHR$ (132): 22007 FORK=1T01000: NEXT:PRINT0992, STRINGS (30,''); C$ 4)=CHR$(136) +CHR$ (140) +CHR$ (174) 22010 RETURN 20300 PCS (5) ECHR$(136) +CHR$ (183)+CHRS (1934 23000 'FLICKER FOR INPUT 20320 PCS (3)=CHRS (168) +CHR$(173)+CHR$(94): 23010 A$=INKEYS: IFAS)\" THEN RETURNELSEPRINTOFL,MS$; *;:FORJE PC$ (6)=CHR$ 193) +CHR$ (168)+CHRS (173) 1TOSO:NEIT :PRINTOFL, FLS;: 60T0 23010 20340 PCS (7)=' +CHR$ (191)+CHR$ (191) 23999 DEF. ELIM 20350 AS=CHRS (166):B$-CHRS (153): 24000 FORHA=1 T040:PRINT DR (1),MTS (RND (3)); NEXT:PRINTDR (1), MTS (1)=A$+CHR$ (162)+CHRS (145) +B$: :: PC (DR(2),1)=0: PC (DR(2), 3)=0:P=DR (1): GOSUB 21000: BD(Y1, X1)=0: MT$ 421=A$+A$+B$+B$: RETURN MTS (3)=AS+CHR$:(174) +CHR$ (157)+B$ 25000 FORHC=1T040:PRINTQCHA, 1), MTS (RND (3));: NEXT :PRINTQ (HA, 1) 20355 RETURN , :PCO(HA, 2), 1) 0:PC(CHA, 2), 3) +0:P-Q (HA, 1): GOSUB 21000: B 20450 IFHX$=\"Y\"THENB19= \":B2=CHR$ (153)+CHR$ (140)+CHR$ (140) + DIY1, X170 CHR$(166): R1$=B16+B25: R25=B25+B18:R46=*:R38=\"FORT=1T08:R35=R325010 EX=EX-1: AJ=PC(QCHA, 2),2): IF (AJ-2)OR (AJ=5) THEN EX=EX-1 $+RIS:R45=R45+R25: NEXTI 25020 RETURN 20500 IFHXS=\"Y\"THENFORI=070832STEP:28:PRINTOI,R48;:PRINT2I+64,R3 26000 IFRV=2THENGOSUB26900:60T026100 $;: NEIT:PRINT2896, R45; 26010 FORJ=0705STEP2: SETASR+J, LN): NEXT: SR=SR45:50SUB26800 26100 LN-LN+3; RETURN 26500 IFRV=1 THENGOSUB26800:60T026580 26510 FORJ-OTOSTEP2: SET (SR-J, LN): NEXT:SR-SR-5:60SUB26900 26580 LN-LN+3: RETURN 26800 16.(B1=KVOR(B2=K) THEN26810EL SESET (SR+1, LN+1): SET (SR+2, LN+27 26810 SR=SR+3:RETURN 26900 IF (BI=K) OR (B2=K) THEN 26910EL SESET (SR-1, LN+1}SETASR-2, LN+ 20520 FOR I =1T032:PRINTOPC(1,1),PCS (PC(1,2));:NEN 20525 IFMT 1THEN20580ELSEFORK=1 TOMT 20530 SD=S0+.528416:3=15:60SUB32000:X-RN: R3=14:GOSUB32000:Y=RN 20532 IF (LANDS = {YAND1) THENX=X+1: IFX>15THENXX-2 20535 P=641Y+41X 20537 FL=P:A-1 20538 GOSUB2150061FAJ=OTHEN20540ELSEA=A+INEA>6THEN20530EL SE2053 20540 BOSUB21000: R3=3:50SUBJ2000: BD/Y1, X1)=-RN:PRINTOP, HTS-BEY 1,1)); 20550 IFY)1 THEN SET (X+2,Y-2): SETAX+5,Y-2) 20560 SET (X+2, +2): SET(X+5, Y+25:60SUB33000 20570 NEXTK 20580 IFBVS=\"#\"THEN20600ELSESD=SE: SR=64: SET(SR,O): SR=SR+1:LN=1 20583 R$=10:60SUB32000:BI=RN+2:60SUB32000:B2-RM+2 20585 FORK=0T014 20586 TFSR>110 THENRV=2EL SEIFSR 20THENRV =1ELSER3=2: GOSUBJ2000: RVRN 20590 IF (SRAND1) = 1 THENGOSUB 26000EL SEGOSUB 26500 20595 NEXTK 20600 RETURN 21000 YI=INT (P/64): I1=-64141/74 21010 Y=1+Y113: X=X118: RETURN 21500 21510 ONABOTO21520,21530,21540, 21550,21560,21570,21520 21520 Z=-60:50TO 21575 21530 V=68:6OTO 21575 21540 Z=128: 60T0 21575 21550 Z=60:50TO 21575 21560 1=-68:SOTO 21575 21570 15-128:60T0 21575 21575 PEFL+2 21580 YIEINT (P/64):X1 = (P-641411/4 21590 AJ=0 26910 SR=SR-3: RETURN 30000 GOSUB33000: IFS=17THENPRINT2960, \"SOUTHEAST WINS\"; ELSEPRINT 960, \"NORTHWEST WINS ; 30010 PRINTOP, \"WIN' 30020 B$-INKEYS: IFB$=\"\"THEN30020ELSEEND 31074 RIVER CHK 31075 IFHX$=\"Y\"THENRV=0: RETURNEL SEKP:P:P=FL:60SUB21000:P=KP:RV=0 31080 ON A GOTO 31085, 31090, 31095, 31100, 31105,81110, 31085 31085 IF(X)120) OR (Y(2) THENRETURNEL SEIFPOINT (X+7,Y-2) THEN RVT 31086 RETURN 31090 IF(1 120) THENRETURNELSE IFPOINT (X+7, +2) THEN RV=I 31091 RETURN 31095 TF02124) THENRETURNEL SEIFPOINT (X+2, Y+3) ORPOINT (X+3,Y+3) TH EN RV=1 31096 RETURN 31100 IF (X(1) THENRETURNEL SEIFPOINT (X-1, Y+1) THEN RV=1 31101 RETURN 31105 IF(X<1 )OR (Y<1) THENRETURNELSE IFPOINTX-1,Y-1) THEN RV=1 31106 RETURN 31110 IF(X)124) OR (Y3) THENRETURNELSE IFPOINT (X+2, Y-3) ORPOINT(X+3. Y-3) THEN RV=1 31111 60TO 31120 31120 RETURN 31999 RANDOM NO. 32000 R1=SD1997:5D=RI-INTURI): RNINT (SDOR3+1: RETURN 33000 PRINT2960, STRIN6916), *); RETURN 34000 F2=0: IF (AJ=7) ORTAJ(1) THENRETURN ELSEIFNOT((S=1) AND (AJ)3)) ORI(S-17) AND (AK4D) THEN RETURNELSEF2=1 : RETURN 35000 LPRINT' .':FORX=1536010163595TEP64: A$=\" 35010 FORY=0T063: A$=A$+CHRS (PEEK IX+Y) 35020 NEXTY:LPRINTAS:NEXTX: A$=\"RETURN 40000 CLS:PRINT, \"TRS-80 WARGAME 1.1 :PRINTS200, THIS SAME SIMULATES A WAR BETWEEN TWO COUNTR TES: ':PRINT2400F NORTHWEST VERSUS SOUTHWEST 40002 PRINTE5B6, PCS (2);:PRINT3816, C515777PRINT3687, PCS (6); :PRIN T3712, PES (3) ; :PRINT2758, PCS (4): PRINT3720, PCS THE 40010 GOSUB51000 COMPUTER & VIDEO GAMES 43 "


"VIC 20 SOFTWARE QUALITY SOFTWARE FOR THE 3.5 VIC 20 COMPUTER DEFLEX TEN SUPERB 3.5 PROGRAMS ALL TEN FOR .95 Fast-moving action and spectacular colour and sound effects add to the excitement of this original game. Deflect the rapidly moving ball to hit stationary or moving targets. Records top ten high scores. 20 skill levels. ROX GEM+ Create and store your own custom character sets. TANX Tank battle for 2 players. MUSIC Encode tunes in three-part harmony up to 130 notes long on 3.5k machine SPACE ZAP Destroy alien spacecraft attacking your space station. BREAKOUT Superb sound and colour effects. HI-RES Sketch on a 128 x 128 pad using keyboard or joystick SPIRO Create spirograph-type patterns in hi-res. VIC TRICKS Program demonstrates the special uses of VIC chip registers MASTERMIND Uses colour and sound to the full WORD GAMES Unusual and challenging game for 2 or more players. At last an original and compulsive space game. Defend your moon base from the deadly ROX from space. Increasing levels of difficulty and superb visual and sound effects make this the greatest new arcade-type game since Space Invaders. DEFLEX and ROX on same cassette .95 dK'tronics? 23 Sussex Road, Gorleston, Great Yarmouth, Norfolk. Telephone: Yarmouth (0493) 602453 ATARI MAIL ORDER BASICS OF ANIMATION: This program shows you how to animate sinple shapes (with sound) using Print & Plot commands and also has a nice Player Missile graphics game you can play with 16K (C) .95 GHOST HUNTER: Rid the mansion on Huckleberry Hill of Ghosts. An exciting, fast action, arcade type game using excellent sound and graphics 16K (C) .95 CAVERNS OF MARS: Fly your attacking spacecraft right into the bowels of an enemy Martians base, blasting away at fuel dumps and Martian fighters as you twist and veer from sodden, cavern rock lizards. The combination of stark haunting subterranean graphics and the fast-paced continuous battle action makes this one of the most exciting games on a computer. 16K (C) .25 INTRUDER ALERT: This is a fast paced graphics game which places you in the middle of the Dreadstar\" having just stolen its plans. The droids have been alerted and are directed to destroy you at all costs. You must find and enter your ship to escape with the plans. Five levels of difficulty are provided. INTRUDER ALERT requires a joystick and will run on 16K systems 16K (C) .99 PLAYER/MISSILE GRAPHICS: This program shows you how to create a simple shape called a player, then takes you through over 25 examples to create a complete business application and a small game. 32K (C) E19.95 SOUND: Unless you have spent many hours experimenting with the four voice channels of the Atari, you will learn a lot from this one. With many examples of special sound effects. 16K (C) .95 FOREST FIRE!: Using excellent graphics and sound effects, this simulation puts you in the middle of a forest fire. Your job is to direct operations to put out the fire while compensating for changes in wind, weather and terrain. Not protecting valuable structures can result in startling penalties. Life-like variables are pro vided to make FOREST FIRE! very suspenseful and challenging. No two games have the same setting and there are 3 levels of difficulty. 24K (C) .99 GALACTIC CHASE: 16K cassette. A fast real time galaxian type game in playing to the fullest ability the graphics and sound capability of the Atari computer. .95 MURDER AT AWESOME HALL: Colonel Awesome and a few friends are gathered at the Hall! Colonel Awesome has just been murdered. Using your incredible powers of deduction can you solve the case? You must find the weapon, the murderer and the room in which the crime was committed. Twenty rooms on two floors, seven weapons and seven possible murderers. Excellent floor plan graphics 16K (C) .95 MEMORY MAP: A list of all those useful memory locations you wish you knew how to access E4 95 MINI WORD PROCESSOR: Requires printer and 32K of memory Suitable for simple editing of text, and storage of text up to 5 pages of length or either disc or tape. Great value. 32K (C) .95 KIDS PROGRAM 1: Three programs on one tape. Maths: test your child's maths skills: Dialogue: talk to your computer: Lost Treasure: search over a small island looking for a treasure 16K (C) .95 BOB'S BUSINESS: Programs on this tape include Amortisation Table, Monthly mortgage payment. Depreciation schedule, Savings and Loan Averages, Square Feet and Yards, Paycheck Calculation, Interest on Investment, Mortgage Companion, Projects Expenses, Monthly Bar Graphics, Decimal Hex Conversions, US Metric Conversions, Checkbook Balancer 32K (C) .95 KIDS 2: Three more programs for your children Spelling Bee, input and test those monthly tests; jumbled up letters give a lot of fun: Touch, follow the computers instructions and stop yourself laughing 16K (C) .95 THE GRAPHICS MACHINE: Type in simple commands like line, boc, circle. polygon, fill and save screen to get hires picturesyou can save and retrieve in seconds. Several demos are included in this great program. 48K (D) E13.50 SANTA CRUZ TRICKY TUTORIALS PLAYER PIANO: Turns your keyboard into a mini piano. Create your own songs save on cassette or disc, up to 400 notes in memory 24K (C) .95 DISPLAY LISTS: Teaches you how to alter the screen format of small and large text on the screen together and high and low res graphics 16K (C) .95 HORIZONTAL VERTICAL SCROLLING: Enables graphics or text to be moved up. down or sideways. You could move only the text on the bottom half of the screen or create a map and scroll smoothly over it. 16K (C) .95 Atari 400 from Atari 800 from Atari 410 16K Ram from 32K Ram P.O.A. .99 .99   PAGE FLIPPING: Learn how to have the computer draw the next page you want to see while you are still looking at the previous page then flip to it instantly. A very useful program. 16K (C) .95 Calisto Computers Ltd. SPECIALISTS IN MICROCOMPUTERS AND SOFTWARE 119 JOHN BRIGHT STREET, BIRMINGHAM B11BE Telephone: 021-632 6458 She S HIS EVEN MORE COMPUTERS AND SOFTWARE 44 COMPUTER & VIDEO GAMES "


"40115 PRINT IF YOU WISH TO MOVE LESS THAN THE MAXIMUM PRESS S 40015 PRINT315,\"OPERATING INSTRUCTIONS: 40020 PRINT 40025 PRINT:PRINT DO YOU WANT A HEX BOARD? IT IS ADVISABLE TO PLAY ON A HEX BOARD UNTIL YOU ARE ACCUSTOMED TO THE MOVEMENT OF THE PIECES. 40030 PRINT\"HOW MANY MOUNTAINS? MOUNTAINS CREATE A MORE INTERESTING GAME. THEY APPEAR AT RANDOM ON THE BOARD. 40040 PRINT DO YOU WANT A RIVER? \"THIS OPTION IS NOT AVAILABLE ON A HEX BOARD. 40045 PRINT ENTER THE SCENARIO NUMBER THIS ENABLES THE SAME SCENARIO TO BE REPLAYED.:60SUB51000 40056 PRINT EACH PLAYER HAS 16 PIECES CONSISTING OF: 40060 PRINTTAB(15); \"NORTHWEST\"; TAB(27); \"SOUTHWEST'; TAB(38); \"NUMB ER'; TAB (46); \"VALUE\"; TAB (54); \"MOVEMENT\" 40061 PRINT 40065 PRINT CAPITAL\"; TAB (20); PCS (7) TAB (30); PCS (7) TAB(40);1; TAB (49);0; TAB(58);0 40066 PRINT 40070 PRINT'ENGINEER';TAB (20) ;PCS (1); TAB (30); PCS (4) ; TAB(40);1;TA B(48); 1; TAB(58);5 40071 PRINT 40075 PRINT'TANK\"; TAB (20); PCS 12); TAB (30); PC$(5) ; TAB(40); 6; TAB ( 48 );2; TAB(58);5 40076 PRINT 40080 PRINT*INFANTRY\"; TAB (20) 3PCS (3); TAB (30);PC(6) ; TAB (40); 8;TA B148);1; TAB(58);3 40081 PRINT 40085 PRINT'OBJECTIVE: THE FIRST PLAYER TO ENTER HIS OPPONENT'S CAPITAL IS THE WINNER. 40090 GOSUB51000 40100 PRINT MOVEMENT: THE FIRST PLAYER IS RANDONLY SELECTED. IF YOU WISH THE OTHER PLAYER TO MOVE FIRST PRESS + C = EACH PIECE WILL, IN TURN, FLIC KER ON THE SCREEN SHOWING THE MAXIMUM NUMBER OF MOVES AVAILABLE. 40105 PRINT'TO MOVE THE PIECE: PRESS DIRECTION 1 TO 6 ACCORDING TO THE FOLLOWING: 40110 PRINTTAB(B); 6; TAB (20);\"(THESE DIRECTIONS ARE ALSO PRINTTA B46);5; TAB (10); 1TAB(20); \"USED TO ATTACK AND RETREAT)':PRINTTAB 6);4; TAB(10);2:PRINTTAB(B);3 YOU MUST STOP IF YOU MOVE NEXT TO AN OPPOSING PIECE (EXCEPT THE CAPITAL). IT TAKES TWO MOVES TO CROSS A RIVER. 40120 60SUB51000 40125 PRINT:PRINT NO PIECE MAY ENTER A MOUNTAIN SQUARE. IF YOU WISH TO MOVE A PIECE IN AN ORDER DIFFERENT FROM THE ORDER FLICKERED PRESS = M = AND THE TRS-BO WILL REPEAT THIS PIECE WHEN OTHER MOVEMENT IS COMPLETE. 40130 PRINT IF YOU DETERMINE THAT MOVEMENT IS COMPLETE AND NO FU RTHER PIECES NEED BE MOVED PRESS = F -, YOU CAN ALSO PRESS =C. THIS IS FASTER BUT DOES NOT CHECK FOR PIECES STILL ADJACENT FRO M THE LAST COMBAT.': 60SUB51000 40135 PRINT ENGINEER THIS PIECE IS ABLE TO CUT A ROAD THROUGH MOUNTAINS. THERE A RE THREE TYPES OF MOUNTAIN:':PRINT: 40140 FORA=1T03:PRINTTAB (A116);A; TAB(A116+5);MTS (A);: NEITA:PRINT FORY=117015STEP4:FORX=44T0108STEP32: SET(1,Y) SET(X^3, Y): NEITT, Y :PRINT:PRINT 40145 PRINT' TO CLEAR THE ROAD MOVE THE ENGINEER IN THAT DIREC TION. A 3 MOUNTAIN CHANGES TO A 2 MOUNTAIN; A 2 TO A 1 AND A IT O A BLANK SPACE. 40150 PRINT THE ENGINEER STOPS WHEN CLEARING THE ROAD AND THE R EMAINDER OF HIS MOVEMENT IS LOST.\":PRINT: GOSUB51000 40155 PRINT \"RIVER IT COSTS TNO MOVES TO CROSS A RIVER UNLESS THERE IS A BRID SE. ENGINEERS MAY NOT CLEAR A ROAD IF THE RIVER IS IN BETWEEN 40160 PRINT:PRINT THE VALUE OF A DEFENDER UNDER ATTACK IS DOUBLE D IF THE RIVER IS BETWEEN THE DEFENDER AND ATTACKER UNLESS IT IS ALSO ATTACKED BY ANOTHER PIECE ON THE SAME SIDE OF THE RIVER.\" GOSUB51000 40165 PRINT\"COMBAT: WHEN PLAYER MOVES AND PLACES A PIECE NEXT TO AN OPPOSING PIECE HE MUST ATTACK. EACH ATTACKING PIECE MUST ATTACK ONEDE FENDER. IF THERE IS AN OPTION, THE PIECE WILL FLICKER WITH AT=, 40167 PRINT THE PLAYER MUST INDICATE THE DIRECTION OF ATTACK. 40170 PRINT\" ALL COMBAT TAKES PLACE SIMULTANEOUSLY ON COMPLE TION OF MOVEMENT\" 40175 PRINT'ATTACKER'S FACTORS: INTEGER VALUE OF 150% OF VALUE O F ATTACKERS. 40180 PRINT DEFENDER'S FACTORS: VALUE OF DEFENDER PLUS ANY DEFEN DER ADJACENT TO ATTACKER PROVIDED THAT PIECE IS NOT ALSO UNDER ATTACK. : 60SUB51000 40185 PRINT\"COMBAT RESULT: ATTACKER'S AND DEFENDER'S ODDS ARE ROUNDED TO SIMPLE ODD S(E.6. 11 VS 4 BECOMES 2-1). THE FOLLOWING TABLE IS CONSULTED AN DA RANDOM ROW SELECTED: 40190 PRINT' 1-6 1-5 1-4 1-3 1-2 1-1 2-1 3-1 4-1 5-1 6-1\":FORA= 1T06: FORB=1T011:PRINTUSING\"**\";TB(A,B); : NEXTB:PRINT:NEITA 40192 PRINT:PRINTS-1 A ELIM: -2 A RET: 0 EXCH6: 1 ELIM: 2 D RE T\":60SUBS1000 40195 PRINT\"-1 ATTACKER(S) ELIMINATED. 40200 PRINT\" I DEFENDER ELIMINATED. 40205 PRINT' O EXCHANGE ATTACKER MUST ELIMINATE UP TO VALUE OF DEFENDER. IF THERE IS AN OPTION THE ATTACKERS FLICKER WITH =EL=. PRESS =E= TO ELIMINATE. PRESS =N= IF YOU DO NOT WISH TO ELIMINAT E.FLICKERING CONTINUES UNTIL SUFFICIENT ELIMINATED. 40210 PRINT\"-2 ATTACKER RETREATS 2 HEX:':PRINT 2 DEFENDER RETRE ATS 2 HEX: 40415 PRINT THE PIECE FLICKERS WITHERTS, IT MUST RETREAT AND NOT PASS THROUGH ANY HEX ADJACENT TO AN OPPONENT OR MOVE OFF BOARD. I F IT CANNOT, PRESS E= TO ELIMINATE. 51000 PRINT3960, \"PRESS ENTER= TO CONTINUE #P-TO PRINT\": 51050 B$INKEYS: IFB$=\"THEN51050 51060 IFB$=\"P\"60SUB35000 51080 CLS: RETURN COMPUTER & VIDEO GAMES 45 code OM part A204 "


"ENGINEERI Have you ever had the urge to build a bridge but just couldn't find the time or place to construct one? If so, then this simulation is for you. The object of this game is to successfully build a bridge from the ground up. You have been hired by the San Francisco Public Works Commission to rebuild the famous Golden Gate which was recently destroyed by a powerful invasion from space. You must connect the two blocks at the top of the screen. You do so by placing beams from the bottom until you can support the connecting beams across the top. There are only a few rules, as you are your own boss. You must have the right end of the beams supported by either another beam or the rocky cliffs on the side. The only other item to be aware of is the ever-present inspector, who will walk up and down during construction. All he asks of you is that you lay beams below his feet only so you can't drop one on his head. The game itself is simple to play and win, so the challenge is in completing the entire work in as few days as possible. To play, all you need is an 8K Atari with one joystick, which goes into the leftmost slot. VARIABLES DA — days of construction so far. X, Y location of inspector. M, N location of pointer on screen 10 GRAPHICS 0:POSITION 13,0:? *BRIDGE BUILDER\":POSITION 19,1:? \"BY\":POSITION 14,2:? \"JAMES HAGANI 15 POKE 752, 1:OPEN #2,4,0, \"K:' 20 ? :? :?YOU ARE NON AN OFFICIAL E NGINEER!!!\":? 'YOUR MISSION IS TO BUIL D A BRIDGE 25 ? 'CONNECTING THE TWO BLOCKS AT THE TOP\":? \"OF OF THE SCREEN. YOU DO SO B Y PLACING\"; 30 ? \"BEANS BELOW THE INSPECTOR'S FEET .':? \"SIMPLY MOVE THE POINTER TO THE P LACE 35 ? 'WHERE YOU WISH TO PLACE THE BEAM THEN\";:? 'ENTER THE DIRECTION YOU WI SH TO SET 40 ? \"THE BEAM. TRY TO CONSTRUCT THE B RIDGE\":? 'IN AS FEW DAYS AS POSSIBLE. :? :?' HIT ANY KEY TO BEGIN...\" 50 GET 12, 150 GRAPHICS 5: SETCOLOR 2.0.0:POKE 752 , 1: SETCOLOR 1,11,10: SETCOLOR 0,15,0: SE TCOLOR 4,8,4 155 COLOR 1 160 FOR Y=0 TO 79:PLOT X, 39: NEXT X 165 PLOT 0,8: DRAWTO 5, 8:PLOT 0,9: DRANT 0 5,9:PLOT 79,8: DRAWTO 74,8:PLOT 79,9: DRANTO 74,9 170 Y=10:D=71:1=4 190 PLOT 0,Y: DRANTO X+3,Y:PLOT 79, Y: DR ANTO X+D-3, Y 200 Y=Y+1: IF INT (RND (1) 110) >3 THEN Y=X +1:D=1-2 210 IF Y=39 THEN 220 215 SOTO 190 220 X=29+INT (RND (1) 117): Y=38 230 GOSUB 1030 240 MEINT (RND (1)131) +25: N=0 260 LOCATE M, N+1, II 262 IF XX< >0 THEN 280 270 N=N+1:60T0 260 280 N=N-10:IF NKO THEN N=0 285 ? :? :?:? :? \"USE JOYSTICK TO MOV BEAM POINTER...':?' DAY. :DA "


"RUNS ON AN ATARI IN 8K WITH A JOYSTICK BY DAVID BOHLKE +1;' OF CONSTRUCTION.\":? 290 COLOR 2:PLOT M,N:PLOT M+1,N 320 FOR IX=1 TO 20:NEXT XX:C=STICK (0): IF C=15 THEN 320 330 IF C=7 THEN 380 340 IF C=11 THEN 400 350 IF C=13 THEN 420 360 IF C-14 THEN 424 370 GOTO 290 380 LOCATE M+2, N, IX: IF XX<>O THEN 440 390 COLOR 0:PLOT M,N:PLOT M+1, N: M=M+2: COLOR 1:60T0 290 483 IF CC=0 THEN D=2:11=18 484 IF C=7 THEN D=3:11=18 485 IF D(1 OR DX3 THEN 480 510 DA=DA+1: M1=M:N1=N 520 FOR I=1 TO 18 525 SOUND 0,100,60,100:FOR XX=1 TO 10: NEXT XX: SOUND 0,0,0,0 530 IF MX76 OR NK 4 OR MC2 THEN 620 540 COLOR 2: PLOT M,N: PLOT M+1, N 550 LOCATE M+2, N, XX: IF XX<>0 AND XXCX3 THEN 770 560 ON D GOTO 570,580,590,600 570 I=I+INT (RND (1) 12):N=N-1:11=11+1:60 TO 610 580 M=M+1: N=N-1:60T0 610 590 M=M+1:60T0 610 600 M+M+1:N=N+1 610 NEXT I 620 LOCATE M+2, N-1, XX: IF IX)0 AND XX< >3 OR D=1 THEN 770 630 M=M1:N=N1 650 ? :? :? *RIGHT END OF BEAM MUST BE SUPPORTED!':? :20=I:FOR I=1 TO 200:50 UND 0,36,36,36: NEIT I: SOUND 0,0,0,0 670 IF QQ=19 THEN 20=18 672 FOR 1=1 TO QQ:COLOR 0:PLOT M, N:PLO T M+1,N 675 SOUND 0,100,60,100:FOR XX=1 TO 10: 860 LOCATE X,Y-1, XX: IF XX=0 THEN Y=Y-1 : 60T0 910 870 GOTO 910 880 LOCATE X+1, Y+1, XX:LOCATE X+3, Y+1, X 1:LOCATE X,Y+1, X2: IF 12=0 AND TY=0 AND X1=0 THEN Y=Y+1:60T0 910 890 LOCATE X+3,Y, IX: IF XX=0 THEN 1=X+1 : 60T0 910 900 LOCATE X,Y-1, XX: IF XX=0 THEN Y=Y-1 : 60T0 910 910 GOSUB 1030: IF Y6 OR X<5 OR X>69 T HEN 930 920 NEXT I 930 REM 960 FOR 1=5 TO 75 STEP 5:FOR J-5 TO 10 970 LOCATE I, J, XX:IF XX<>0 THEN 990 980 NEXT J:GOTO 240 990 NEITI 1000 FOR Z=1 TO 5:FOR 71=200 TO 80 STE P-7: SOUND 0,11,10,7:SOUND 1, Z1+7,10,7 SOUND 2,71+14, 10,7:NEXT Z1:NEIT Z 1005 ? \"YOU'VE FINISHED!!!!!!!! IT TOO K YOU\":? 'A TOTAL OF \";DA;' DAYS!!!!!!! 1007 FOR X=D TO 2: SOUND X,0,0,0:NEXT X 1010 ? \"PRESS ANY KEY TO PLAY AGAIN... ......:GET 12, A: RUN 1030 COLOR 3: PLOT X,Y:PLOT X+1,Y-1: PLO T X+2,Y: PLOT X+1, Y-3: PLOT X,Y-2:PLOT X +1, Y-2:PLOT X+2, Y-2: RETURN 1050 COLOR 0:PLOT X,Y:PLOT X+1, Y-1:PLO I X+2,Y:PLOT X+1, Y-3:PLOT X,Y-2:PLOT I +1,Y-2:PLOT X+2,Y-2: RETURN 400 LOCATE M-1, N, XX: IF XX<)0 THEN 440 410 COLOR 0:PLOT M,N:PLOT M+1,N: M=M-2: COLOR 1:60TO 290 NEXT II: SOUND 0,0,0,0 420 LOCATE M, N+1, XX: IF XX< >0 THEN 440 680 ON D GOTO 690,700,710,720 421 COLOR O:PLOT M,N:PLOT M+1, M:N=N+1: 690 N=N-1: 60T0 730 COLOR 1:6OTO 290 700 M+M+1:N=N-1:60T0 730 424 COLOR 0:PLOT M, N:PLOT M+1, N:N=N-1: 710 M+M+1:60 TO 730 IF NK1 THEN N=1 720 = +1: N=N+1. 425 COLOR 2:60TO 290 730 IF NK2 THEN 750 440 IF NCY THEN ? :? 'STICK MUST START 740 NEXT I BELON INSPECTOR!!: COLOR 0:PLOT M.NP 750 REM LOT M+1,N:COLOR 1 760 GOTO 240 450 IF NCY THEN FOR I=1 TO 200: SOUND O 770 SOUND 0,0,0,0:IF W=0 THEN W=1:60T0 ,36,36,36: NEXT I: SOUND 0,0,0,0:60TO 24 790 780 W=0 459 REM in lines 460-465: 790 ? ' INSPECTION...':? :? d=shift-down arrow 810 FOR I=1 TO INT(RND (1) 140)+10 r=ctrlR f=ctrl-F 820 SOUND 0,60,6, 10:SOUND 0,0,0,0:605U 460 ? :? :? USE JOYSTICK TO SET B 1050 BEAM\":? 'IN EITHER d ORFF DIRECTION 830 IF W=1 THEN 880 465 ? 'TO SET IN + DIRECTION, PRESS BU 840 LOCATE 1-2, Y+1, X1:LOCATE X,Y+1,12: TTON. LOCATE X+2, Y+1, X3: IF X1=0 AND X2=0 AND 480 D=0:C-STICK (0):CC=STRIG (0):IF C=1513=0 THEN Y=Y+1:60T0 910 AND CC=1 THEN 480 850 LOCATE X-1,Y, XX: IF XX=0 THEN X=X-1 482 IF C=14 THEN D=1:11=18 : 60T0 910 "


"LANDER MOON CONDITION REDI \"Commander... the space shuttle's fuel tank is leaking. We have to make a forced landing on the lunar surface — and soon. The fuel is fast running outWhat shall I tell the passengers ? Commander...\" You have the lives of the shuttle's passengers and crew in your hands as your craft plummets towards the moonscape, hundreds of barren lunar miles from safety will you save them? Unlike most lunar lander games Moon-Lander provides lateral thrust controls which acclerate the craft left and right rather than just moving it. Facilities are also provided for changing your fuel capacity, vertical thrust, lateral thrust, and the strength of gravity. You have four instrument readings and a video display of your landing. The instruments consist of two speed indicators one vertical and one horizontal a fuel gauge, and last, but not least, an altimeter, Using these instruments you must land, with a vertical velocity of 10 metres/second or less, on a reasonably flat piece of ground. The program is written in Acorn Atom Basic for a machine with a fully expanded lower text space. For those with other machines who may want to convert the program to run on their systems the shortened form of the statements is usually the first one or two letters of the relevent statement followed by a dot. Variables preceded by a % symbol are, unlike the convention used by most other Basics, real variables, and those without the % are integer variables. All GOTOs and GOSUBs in the program use labels for speed ie G. A. program control to the section beginning with the label in the given program this would be line 1090. Returning to the program itself line 30 calls the instruction printing subroutine which, having printed the instructions, waits for the shift key to be pressed before returning control to the main program. Lines 40 to 140 then input fuel capacity, gravity, etc and check for illegal inputs. The following lines, up to line 320 set the screen to graphics mode nought and draw the moonscape with two randomly positioned, random height peeks. Line 340 prints out the instrumentation headings (P.$30 homes the cursor). Lines 350 and 360 turn the moonscape grey, and lines 370 and 400 place 80 stars (white pixels) in random formation on the screen. The next two lines perform all the necessary initialisation (height, fuel, etc), and then, at line 430 the main program loop starts. Lines 440 to 470 mirror the effect of gravity and input the controls — the instrument readings are then updated by lines 480 to 550. Control is then transferfed to the routine with label 'A' which starts at line 1090. This routine works out the new position of the lander and replots it accordingly. The next three lines in the main loop (570 to 590) check to see if the craft has landed or gone off-screen and, depending on the results of these tests, either loop back to line 430 or continue to line 600. Lines 600 to 700 then determine whether or not the ground on which you touched down was acceptably flat. Lines 710 to 1080 output the evaluation of your piloting abilities. 48 COMPUTER & VIDEO GAMES "


"BY S. DRAPER RUNS ON AN ACORN ATOM IN 12K MO 1@DIMHH63, NN8 20Q=#9000) L=#9090 30GOS. i 409P. $12$10$10 50FIN. \"GRAVITY (1 TO 10 )\"%G 601F%G<BOR%G>10P. \"BETWEEN & 10.\");G.9 70hp. $10;FIN. \"THRUST (0-20%\"%T 800=#7F7F7F7F; H=32 901F%T OORZT%20P. \"BETWEEN 0 & 20.\");G.h 100 JP.$10; IN. \"FUEL CAPACITY (1-999)\"G 110IFG<10RG>999P. \"BETWEEN 1 & 999); G. 120KP. $10;FIN. \"LATERAL THRUST (0-2)\"%R 130IF %R OOR %R>2;P. \"BETWEEN AND 2.\"); G.K 140yGOS.W 150CLEARO 160X=0; Y=5; F=G; HHO=5; R=A.R.%54 17OMOVEO.; DRAWO,5 1801P=A.R.%54 190IF(P<R+9A.P>RDOR(R<P+9A.R>P>;G. 1 200T=P; IF R.%3>G. 2100T=A.R.%54 2201FCT<R+9A.T>R SORC RCT+9A.R>T); G.O 230nDO X=X+1 2401F X>R A. X<R+9G.P 250Y=Y+R.%3 260IF A.CX-PX50R A.CX-TX5.G.9 279 IF Y>15 Y=14 280P MOVEX, 290DRAWX, Y 300IFY Y=0 310HH(X)=Y+5 3200. X=63 330B=#40404040;T=#40404040; Y=#8000; V=176 340P. $30 \"ALT: F: V.V: H.V: 350F. I=#8000TO#8200 360?I=?I 1128;N. 370F. I=1T080 380X=#8000+A.R.%512 3901F?X=1920R?X<128; ?X=65 400N. 410%.Z=44;%V=0;XH=0;%S=FLTCA.R.%56+1) 420M=1 430DO 440r%V=%+%G 450IF?#B001<128;%H=%H-%R 4601FC?#B002 >864< >64%H=%H+%R 470IFC?#B001 %&64< >64AND F>0; XV=%Y-%T; F=F-%T; IF FCO F=0 480?#8013=V+A.XV/100;?#8014= V+A.((%>%100/10 490?#8015=V+R.C%>%10;?#8012=171, IF%<0; ?#8012=173 500?#801C=V+A.((%>%10) 510?#890A=V+F/100)?#800B=V+(F%100)/10;?#800C=V+F%10 520?#8004=V+%2/100; ?#8005=V+((%2)%100/10 530?#90065V+C%2>%10 540x=%; ?#801E=V+A.%CC%H-X)*10) "


"HOW TO GET SERIOUS ABOUT ZX GRAPHICS FOR ONLY .50 PLOT Fed up with listings that ignore the graphic approach? Is your PRINTING and PLOTTING still guesswork? Do you want to write data programs with graphic PRINTAT and PLOT and professional looking windows and scrolls? Or maybe you're still trying to find the successor to Space Invaders! All you need is ingenuity... and the PRINT'N'PLOTTER JOTTER. It's the professionally produced ZX Graphicsaid designed by enthusiasts.... for enthusiasts. Just take a look at the specification-then think of the possibilities for real graphic graphics! PRINT N'PLOTTER FILM TOO FOR ONLY .25! Jotter 'FILM' is a matt Polyester film version of the \"JOTTER\" Grids identical in size so you can co-ordinate precisely PRINT and PLOT or you can copy photographs, drawings, maps, charts! The surface of the film is ideal for drawing (with pencil) and erasure With both JOTTER and FILM the graphics possibilities are enormous despite low resolution. Isn't it time you got serious about ZX Graphics? Flyleaf cover PRINT ZX8180 2 hole punched. Post to Butler, Currie & Hook, 19 Borough High Street, London SE19SE. Please send me **Jotters' @.50 (inc VAT, P&P) Please send me \"Films\" @  [inc VAT, P&P) Please send me your illustrated leaflet-lenclose a stamp Please bill my Access/Barclaycard No. PRINTPLOTTERJOITER your ZX 81 into werful picture Numbered PLOT Grid. Numbered PRINT Grid. Program ZX81 Keyboard. Board backing notes 100 Sheets. Size A4. Also available over the counter at Deriny's Booksellers, 2 Carthusian St, London ECI Buffer Micro Shop 374a Streatham High Rd London SW16 Name Address Livros e seriament and remove the presenta com a non Post Code All goods are despatched within 48 hours of receipt. If you requires Class return post please add 50p 10 Jotter price TWICKENHAM W20 COMPUTER CENTRE LTD With the best microcomputers available C commodore apple ] V2 day Wednesday 'phone for latest Prices PRINTERS SOFTWARE ACCESSORIES Anadex Micro Modeller Z-80 Softcard Epsom Visicalc Monitors Ricoh Magic Window Graphics Tablet SPECIAL * OFFER WE PAY YOUR VAT ON MOST ITEMS NEW TO OUR RANGE Prestel.th lan .00+ VAT. 01 892 7896 01 891 1612 TWICKENHAM COMPUTER VISA CENTRE LIMITED 72, Heath Road Twickenham Middlesex TW1 4BW 50 COMPUTER & VIDEO GAMES "


"55@?#801B=171; FIF%H<@;?#801B=173 560G. 570CIF%Z<0;%S=10;G.M 5801F%S>560R%S<1G. 590U. %Z<HHC%S+1 +20RXZ<HHCXS+3)+20RXZ<HHCXS+6)+2 600B=0 610F. I=%S-C%S %2 TO %S-C%S %%2+6 620NNC I +1-%S )=0 630IF HHCI >>B B=HHCI) 640N. 650F. I=%S-(%S %2 TO %S-(%S %%2+6 660IFHHC I XB-7NN1=1; NN2=1; NN3=1;G. 67NNC B-HHCI)=1 680sN. ;C=D 690F. I=@T07, IFNNC I)=1C=C+1 700N. 710P. $12$10$19\" YOUR TOUCH DOWN VELOCITY WAS\" 7200=0 730P.XV\" METRES PER SECOND WHICH \" 740034 7501FXX<6P. \"WAS LOVELY\"); G.d 7601F%V<11P. \"WAS A BIT ROUGH ON YOUR PASSENGERS.\");G.e 7701F%<15P.\" MODERN LANDING CRAFT JUST CAN'T TAKE.\"); G. f 780P.\"IS SOMEWHAT HIGH.\") 790P. \"I DON'T KNOW WHAT YOU THINK YOUR\" 800P. \"DOING, BUT YOU WON'T BE DOING IT\" 810P. \"ANY MORE YOUR SHIP HAS JUST\": 820P. \"BEEN SPREAD LIBERALLY OVER 50\" 830P. \"SQUARE KILOMETERS OF MOON-\" 840P. 'SURFACE.\" 850IFC<3G. 8601FC>2P.\" AND TO TOP IT ALL OFF, YOU\" 870P. \"DIDN'T EVEN MANAGE TO FIND A\" 889P. \"FLAT PIECE OF GROUND TO LAND ON!\" 890G. t 900DIFC<3G. 910P.\" HOWEVER, YOU DIDN'T\");P. \"FIND A FLAT AREA TO LAND\" 920P. \"ON AND YOUR SHIP WAS DESTROYED\": 930P. \"ANYWAY.\";G.t 940e IFC<3G.t 958P. \"HOWEVER, IN VIEW OF THE FACT\": 960P. \"THAT YOU CAME DOWN ON ROUGH 970P. \"GROUND I SHOULDN'T THINK THEY\" 980P. \"FELT MUCH SINCE YOUR LANDER WAS\" 996P. \"SPLATTERED OVER A FAIRLY LARGE\" 1000P. \"AREA.\"); G.t 1010f IFC<3G. t 1020P.\" IN RETROSPECT YOUR TOUCH\": 1830P. \"DOWN VELOCITY WAS LARGELY \" 1948P. \"IRRELEVENT SINCE YOU SUCCEEDED\": 1050P. \"IN FINDING A MINATURE MOUNTAIN\": 1060P. \"RANGE TO LAND ON AND YOUR SHIP: 1070P.\"WAS DESTROYED ON IMPACT.\") 1080G. 1090a IFM=16.b 1100IFPKY+H; G.b 11101 PER;P!H=B "


"MICROAGE ELECTRONICS LONDON'S BIGGEST ACORN STOCKIST GREEN SCREEN Juan ***** ACORN OFFICIAL BBC STOCKIST FROM THIS TO THIS ATOM KITS ORDERS TAKEN NOW In our books the best computer FOR BBC MACHINE AT THE FLICK OF A SWITCH kit available. Build yourself an Acorn Atom for only . With the new ZENITH Monitor. Choose between small or large format plus .50 p+p depending on what you're doing. Small format for definition, ATOM SOFTWARE large format for display. Full 12\" GREEN screen, Only  while Games Packs 1-8, Database, stocks last. It doesn't change the output from your computer, just FORTH, Atomcalc, everything changes the size of the display. Ideal for VIC 20, TRS 80, Atom, BBC in stock. 30p ptp + Genie machines. .50 p+p BBC ROM RACOMM COLOUR MONITOR Update your Atom to the BBC Blank Absolute high resolution. 700x300 operating system Cassettes pictals 12\" +  ptp Atom, Atom Discpack.  40p each, BBC, & Genie machines. THE GP-80A dot matrix printer. 5% discpack only , operating .50 ATARI VIDEO SYSTEM GAMES LOWEST EVER PRICE manual, cables. plus .50 p+p ONLY  .50 ptp for 10. Warlords .95 DAI Personal Computer.  Dot Matrix, Full 96 ASC11 70pp+p Missile Command .50 48K RAM 24K ROM character plus many, many more The BBC Cassette Recorder  ACTIVISION GAMES ZX81 Owners  off As chosen by the BBC, but Also available: Skiing .95 Bring us your working ZX80 or 81 2114 IC's, Paper for most cheaper! .50 pp Kaboom. .95 and get  off any AtomIf it's not in the advertisement, printers, Enormous selection of plus many, many more send for our mail order lists. kit or built. Books, Leads, etc, etc, etc, 30p pip ALL PRICES INCLUDE VAT ABSOLUTELY NO MORE TO PAY. 135 HALE LANE EDGWARE MIDDLESEX HAS 90P SEE US AT COMPUTER FAIR 23-25 APRIL TEL:01-959 7119 TELEX 881 3241 MICROAGE ELECTRONICS ZX-81 16K SOFTWARE The breakthrough you've waited for: PROGRAM THE ZX-81 IN ENGLISH!! with GAMAL 81, you can now write adventure programs in hours not weeks and with GAMAL 81 you'll have every adventure you'll ever want for the price of one. Comes on cassette with instruction book, .95. (requires 16K) (.00 see below) PACK 16/1 includes all of: AIR TRAFFIC CONTROL: Animated radar screen of busy airport shown, you must bring planes into land; INVADERS: INVADERS SELF PLAY: PHONEBOOK; keep friends and relatives numbers on cassette; DATE '81: computer dating program, who will it pick for you? ALL ONLY .95 PACK 16/2 includes all of: ADVENTURE ATLANTIC: You may become very rich or you may be marooned forever; BREAKOUT: SQUASH PRACTICE: TRANSLATOR: translates any European language to any other, vocab on cassette; COMPUTAPRINT: use this program to predict horse races, or football pools! ALL ONLY .95 Both packs come with full instructions, booklets and are saved on cassette ready to run. ZX-81 PACK 16/1 ONLY .95 SAVE .95 PAXK 16/2 TAPEBOOK 50 version 3 PACK 16/1+ ONLY SAVE PAXK 16/2+ Tapebooks 50.3 .95 .90 SPECIAL OFFER TO ZX-81 OWNERS GAMAL is .00 only if you order either offer 50 PROGRAMS for the IKRAM ZX-81. The latest version includes: SQUASH, INVADERS, COLUMBIA, SPLAT, INTEGRATION, BANK A/C, CREDIT CARD CALCULATOR AND LOTS MORE. All on cassette and ready to run now. With full instructions. Still amazing value at .96 the lot. CONTROL TECHNOLOGY 39 Gloucester Rd, Gee Cross, Hyde, Cheshire SK14 5JG 061-368 7558 ZX AUTOCODER Converts Basic to Machine Code Automatically You enter your Basic program and Autocoder prints out the equivalent 280 assembly language program .95. C*tech Big ideas for small computer all software by return of post!! 52 COMPUTER & VIDEO GAMES "


"11206%2=%2-%V/10;%S=%S+%H; IF%8>56;G.C 11301F%S(1G.C 1140P=Y+%5/2-H**%2/3)+512 1150IFP<Y+H;G.C 1166M=0; R=!P;B=P!H 1170G. (1180+30*((%2)%3>) 1180!P=#40424140IR;P! H=#4C7C7C4CIB 1198 IP P80 PI H=P! H&D 1200G.C 1210!P=#40484740R;P!H=#70707070 B 1220!P=!P&O;P!H=P!H&O 1230G. 1240!P=#436F5F431R;P!H=B 1250!P=! P&O:P! HOP!H&O 1269G.C 1280tGOS.W 1290xP.$12$10$10; IN. \"WOULD YOU LIKE ANOTHER GAME\"$Q 1309$L=$Q: Q?1=13 1310IF$Q=\"Y\"G.U 1320IF$Q=\"N\" G.V. 1330P.$L\" NOT VALID, PLEASE REDO.\" 1340F. I=1T080; WAIT:N. 1350G.X 1360VP. $19\"AW SHUCKS....BYE\" 1370F. I=1T015; WAIT;WAIT.P. \"E\";N. 1380P.' E. 1390P. $10; IN. \"WITH PRESENT GRAVITY, THRUST, ETC\"$ 1400$=$Q; 74Q+1 )=13 14101F$Q=\"Y\"G. 14201F$Q=\"N\"G.9 1430P.$L\" NOT VALID, PLEASE REDO.\");G.U 14409IFR.%4>2G.P 1450Y=Y+A.R. 24 1460G.P 1470iP. $12$10$10\" MOON LANDER\" $10 1480P.\" THIS IS A MOON-LANDING\" 1490P. \"SIMULATION IN WHICH YOU PILOT\": 1500P. \"THE LANDING CRAFT.\") 1510P.\" IN ORDER TO SURVIVE THE\" 1520P. \"LANDING YOU MUST LAND ON FLAT\"> 1530P. \"GROUND WITH A VERTICAL VELOCITY\": 1540P.\"(V.V.) OF LESS THAN 11 METRES\": 1550P. \"PER SECOND. TO DO THIS YOU HAVE 1560P. \"THE FOLLOWING CONTROLS:\"/ 1570P.\" SHIFT'-ACCELERATE LEFT.\") 1580P.\" REPTY -ACCELERATE RIGHT.\") 1590P.\" CTRL' -ACCELERATE UPWARDS.\"* 1600GOS.W 1619P. $12519\" ON THE DISPLAY AS WELL AS 1629P. \"THE VIDEO OF YOUR LANDING ARE\"? 1630P. \"YOUR INSTRUMENT READINGS -\") 1640P. \"VERTICAL VELOCITY-V.V. (-VE UP),\" 1650P. \"HORIZONTAL VELOCITY-H.V.\" 1660P.\"(+VE RIGHT), ALTITUDE-ALT AND\" 1670P. \"FUEL-F.\"? 1680P.\" ALL PARAMETERS ARE VARIABLE\" 1690P. \"BY THE USER BUT NOTE HIGHER\" 1700P. \"THRUSTS MEAN MORE FUEL IS USED.\" 1710GOS.WR. 1720wP. $18\"PRESS 'SHIFT' TO CONTINUE.\" 17302IF?#B001>127G. Z 1748R. COMPUTER & VIDEO GAMES 53 "


"Deep beneath the waves lurks a horribly beweaponed submarine waiting for its prey — a convoy of cargo ships protected by launches, fast patrol boats and aircraft carriers. The aim is score the highest number of points in one minute. You have an unlimited supply of missiles which are fired by pressing 0. If O is pressed again before the first missile has reached its target it will self-destruct and a second will fire from the sub. Bonus points are awarded for accuracy. The closer to the centre of the ship your missile lands the more points you score. I and P are used to move the sub left and right. The highest score for this program so far is 1100. Can you beat it? Notes on the program: S$=submarine: T${cargo ship. E=2; C$=carrier, E-I; LA$=launch, E=3; SP$=speedboat, E=4. B: random number -I or I, which decides which direction T$ AND C$ move. C: height of the missile. It is used to stop the missile going over the scenery. D: random number, 1, 2 or 3, which decides the height of the ships up the screen and volume of sounds. E: changes for each ship and is used for scoring and printing of the sinking ships. G: random number 1-10, which provides probability of ship appearing. I: gives the horizontal position of the missiles. J: used as a delay to create radar sound. 5 POKE 36879,61 7. GOTO2000 :REM INTRODUCTION 10 PRINT\" : 11 DEFFNR(X) INTCXWRND(2))+1 REM RANDOM NO. 12 NO=36877:V=36878:50=36876 REM WHITE HOISE VOL. & SOUND 15 REM BACKGROUND 20 PRINTITR 30 PRINT\" .... 35 PRINT\" 45 PRINT\" 50 REM SUB & SHIPS 110 S I RET \":T-8:0030720 120 T L 2 2062 130 SP$=\" TER . THIS 26 F 14a C$\" ER D ER 150 LA$=\" har NTU SATU 155 IFK=1 THEN2065 157 REM SAND ON BOTTOM 162 PRINTS WIBIDITIONS \";S:PRINTTT 170 POKE8185,227 :POKE38905,7 180 POKE 198.0REM CLEAR KEYBOARD BUFFER 190 TI$=\"000000\" 270 GOT0700 280 IFTI$%\"000100\" THEN292 285 IFCOTHEN650 :REM MOVE MISSILE 290 GOTO1000:REM MOVE SHIPS 292 POKENO,0 295 PRINT YOUR SCORE IS\";SC:FORT=1T0seee .NEXT:CLR:GOT016 300 POKESO. :POKE 38417,1 :GETA:IFA$=\"0\"THEN600:REM TEST FOR FIRING 305 IFPEEK (203)=64 THEN280 310 IFPEEK(203) 12 THENT=T-1 :GOTO500 320 IFPEEK (203)=13 THENT=T+1 :GOT0500 340 GOTO280 400 REM MOVE SUB 500 IFTCOTHENT=T+1 :GOT0289 510 IFTD14THENT=T-1:GOT0280 520 PRINT\" STORIINICIO Cotto\" TAB<T>S$:GOTO288 590 REM START MISSILE  IFFEEK (4) =93THENFOKEM, 32 618 POKESO,250 :M=8100+T: POKEM,93:POKEM+C0, 1:C=1 :I=T+1 :GOT01000 642 REM MOVE MISSILE 650 POKESO POKEM,32:M=M-22:0=C+1 660 IFC15THENC=@:GOTO1000 675 IFPEEK(M)=32 THENPOKEM+C0,1 #POKEM,93:GOTO1000 680 GOSUB910:GOSUB1500:CO:SC.SC+(20#E) 700 D=FNR(3) G-FNR(12) REM D-VOL. & HGT. SUB ATT 54 COMPUTER & VIDEO GAMES "


"710 BOINT 24RND(i))*2-1 :REM DIRECTION OF SHIPS 715 GOSUB900 :POKEV.D 720 ONGGOT0752,780,782,780,802,800, 800, 800,838.833 750 PRINTSP$T(4)=U:E=4: POKENO,152:GOTO1080 780 POKENO,210 :E=2 785 IFB=1 THENT(2)=0.PRINTT:GOT01000 790 T (2)=14:PRINTTAB(14)T$:GOT01000 800 E=1 : POKENO, 230 810 IFB=1 THENT(1)=:PRINTC#:GOT01000 820 T(1)=14:PRINTTAB(14)C#:GOT01000 839 POKENO,148:PRINTTAB(14)LA$:T(3)=14:E-3:GOT01900 999 PRINT \":FORX=1 TOD :PRINT:NEXT:RETURNEREM SETS THE HEIGHT 910 GOSUB900 :PRINTTABCTUR E , W:POKEV, 15 #REM EXPLOSION 929 FORX=255T0128STEP-1 :POKENOX NEXT:POKENO,250 921 GOTO1512 922 REM SINKING 923 FORX-15TOESTEP-.04:POKEV,X:NEXT 925 POKEW 2:POKE198,6 930 POKENO.0.GOSUB900:RETURN 999 REM MOVE SHIPS 1000 POKE38417,0 1902 T=J+1 :IFJ-10 THENJE: POKE36876,230 :REM RADAR SOUNDS 1003 GOSUB900 1005 ONEGOT01690.1@5a, 1110, 1012 101 T4 T4+1 1015 IFT<4>>16THENGOSUB 1500 GOTO700 1920 PRINTTABCTC4> SP:GOTO380 1050 T(2)=TC2)+B 1955 IFT 2) -10RT(2)=16THENGOSUB1500.GOT0702 1060 PRINTTABCT (2)T$:GOTO800 1990 T(1)=T(1)+B 1995 IFT(1)-10RT(1)=15THENGOSUB1500.GOT0700 1100 PRINTTABOT 1 >>C$:GOTO300 1110 T(3) T 3)-1 1120 IFT(3) COTHENGOSUB1500.GOT0700 1130 PRINTTABCT(3) LA$:GOT0300 1500 PRINT\" 1595 PRINT\" \"RETURN:REM CLEARS SHIPS FROM SCREEN 151 GOSUB900: GOSUB1500 1515 PRINT ID\"SPCCTCE) R p . ---:REM SINKING SHIP 1517 REM BONUS POINTS 1520 IFIT(E) +3THENSC=SC+(TCE)+6-1 10.GOT0923 1530 SC-SC+CI-TCE))*10:GOT0923 2000 PRINTING********************** >>>>> SUB-ATTACKK<\", 2005 PRINT\" N*** *************** ** 2010 PRINT\" BY STUART HALL. 11, BEELEY CLOSE,\" 2020 PRINT\" INKERSALL. CHESTERFIELD.\" 2030 PRINT\" DERBYS.\" 2040 FORX=1 T0709@:NEXT 2050 PRINT DESTROY AS MANY ENEMYPSHIPS AS POSSIBLE IN ONE MINUTE.\" 2060 K=1:GOT011e 2065 K2070 PRINT\" :C: 20 POINTS\". 2080 PRINT\"\",T#\" 40 POINTS\" 2090 PRINT\" LA$:\"W 60 POINTS\" 2100 PRINT ,SP$: 80 POINTS 2102 PRINT\" ST + BONUS POINTS!\" RUNS ON A VIC 20 IN 3-5K 2105 FORX=1T07000 :NEXT 2110 PRINT\" CONTROLS :\" 2130 PRINT\" I MOVES LEFT\" BY STUART HALL 2140 PRINT\" P MOVES RIGHT\" 2150 PRINT\" 0\" FIRES A MISSILE\" 2160 PRINT\" PRESS A KEY TO START.\" 2165 POKE198,0 2179 GETR$:IFRE=\"THEN2170 2180 GOT010 ACK COMPUTER & VIDEO GAMES 55 "


"BU 10 CLS:DEFINTA-Z:CLEAR500: RANDOM 20 DIMX(15), H(15).CP (15), T(S),K3 (30), 4(30).FH(30) LS 14).M(14) 25 DIM HS(2), VHC6), (2), JJC28).K(1), KK (6).L<18).LL(S).263 3e DATA 1112, 11131114,1115, 1116, 1222.2223, 2224, 2225, 2226 1 DATA 1333. 2333.3334, 3335,3336, 1444, 2444,3444, 4445.4446 32 DATA 1555,2555, 3555.4955.5556.1666.2666.3666.4666,5666 33 FORIE1T030: READK3(I): NEXT 40 DATA 11112. 11113 11114, 11115, 11116.12222.22223.22224, 22225, 22226 41 DATA 13333.23333.33334.33335.33336. 14444, 24444.34444.44445,44446 42 DATA 1555525555, 35555,45555,55556.16666.26666.36666.46666,56666 43 FORI=1 TO 30: READK4(I): NEXT 50 DATA11122, 11133 11144, 11155, 11166.11222.22233, 22244, 22255.22266 51 DATA11333.22333.33344.33355, 3336611444.22444,33444.44455.44466 52 DATA11555, 22555, 33555, 44555.55566.11666.22666.33666,44666.55666 53 FORI1T030: READFHCI) NEXT 60 DATA11234. 12234, 12334.12344, 12346.22345.23345, 23445,23455 61 DATA 13456.33456.34456, 34556.34566 62 FORI=1T014: READLSCI): NEXT 70 DATA 12345.23456 80 FORI=1T02: READHS(I): NEXT 118 DATA 11111.22222, 33333.44444.55555.66666;FORI=1T06: READVHCI): NEXT 111 GOSUB38000 130 C :GOTO 3700 140 CLS ELSE PRINTVS# 150 IF AX<>1 PRINTOO. VS$+Z 3.. \"TAB(23)X(1) TAB(26)/ 160 PRINT264,\"1. ACES 1+1+1 = \"+TABC60) X(9) 170 PRINTTAB(28) 9.3 OF A KIND (TOTAL DICE 180 PRINT0128. 2. TWO'S 2+2+2 = 6..\" TAB(23)X(2) TAB (26) 190 PRINTTAB(28>\"10. 4 OF A KIND (TOTAL DICE) \"TABC60) X(10) 200 PRINT0192,\"3. THREES 3+3+3 = 9..\"TAB(23)X(3) TAB(26) 210 PRINTTAB(28) 11. FULL HOUSE <SCORE 25) TAB(60)X(11) 220 PRINTS256, \"4. FOURS 4+4+4 = 12. \"TAB (23)X(4) 1 TAB(26)\"/\" TABC60)X(12) 230 PRINTTAB(28) \"12. LOW STRAIGHT (SCORE 30) 240 PRINT2320,\"5. FIVES 5+5+5 = 15.. \"TAB(23)X(5) TAB(26)/ 250 PRINTTAB(28) \"13. HIGH STRAIGHT (SCORE 40\" TAB(60)X(13) 260 PRINT384,6. SIXES 6+6+6 = 18.. \"TAB(23)X(6) TAB(26) 270 PRINTTAB(28) \"14. YAHT ZEE (SCORE 50) \"TAB(60)(14) 280 PRINT0448,\"7. TOTAL IF 63 +35) \"TAB(23)X(7) TAB(26) \"/\": (TOTAL DICE TABC68)X(15) 298 PRINTTAB(28) \"15. CHANCE 300 PRINTAS12.\"GRAND TOTAL CLEFT SCORE + RIGHT SCORE).. 310 FORI=T01 25: SET (I. 27): NEXTI 320 RETURN : NEXTI 340 FOR 1=1T015:HCI1:CP (I) 369 FOR 1 TO 15:X(T) =HCI) NEXT I: GOSUB140 378 PRINT2640. \"YOUR THROW \":25: 380 PRINT TAB(26) \" ABCDE\" 390 PRINT2704, \"YOUR SCORE \"12 \"TAB(59) RUNS ON A VIDEO GENIE Lady Luck presides over the popular dice game of Yahtzee) but you make the calls, and the computer makes a worthy opponent. For those not familiar with Yahtzee, it involves five dice but a good deal of skill and judgement as well as a fair slice of luck. There is a poker type scorecard for each player with a list of things to be achieved and scored. The player throws the five dice and decides which section of the scoresheet that throw is dedicated to. The scoresheet is made up of: ones, twos, threes, fours, fives, sixes, high run (2, 3, 4, 5, 6) and low run, four of a kind, three of a kind, two pair, a full house, a pair, a Yahtzee and a chance. Bonuses are scored for making a Yahtzee (five-of-a-kind) and scoring well on the first section: ones-sixes. Say the player throws 2, 2, 2, 6, 5. He then has the choice of trying for: a three of a kind, threes on the lefthand side of the scoreboard or keeping the three twos and re-rolling the other two dice to achieve a four of a kind or a Yahtzee. Three throws is the Jimit before he fills in his scorecard. If he is not successful in his two further throws he can still go in the first two options, if however, he fails to score any of the combinations, he scores O in one of the boxes. The game involves a fair amount of strategy and the computex plays a fair game. But there is plenty of scope for improvement and all that is needed is to add to the data statements in lines 30000 through to 30140, or try adding further options to lines 7310; 7365; 7305; 7414. Yahtzee is written for the Video Genie but it will work on a TRS-80 and, as there are no PEEK or POKE statements, the reader should have little difficulty in adapting the graphic part to other machines. Arrays: x(15) is used to swop data when turns are transferred from computer to human, or vice versa. H(15) Stores human scorecard, CP(15) Stores computer scorecard. t(5) Is for storing throw of dice. z(3) Is used for storing 3 new throws by computer YAHTZEE BY KEITH HOOK 400 GOSUB 640: GOSUB1010 402 GOSUB691 403 IF X$<> \"N\"GOSUB691 410 PRINT2832. \"WHICH SCORECARD DO YOU WANT TO USE LEFT) OR RCIGHT ?\" 411 X**INKEV: IF X GOT0411 420 IFXE=\"L\" GOSUB 1300ELSE IFX=\"R\"GOSUB 2009 421 GOSUB 140: GOSUB 15000 432 FOR I = 1 TO 15:HCI-XINEXT I 433 IFX(7)<> ANDX(8) >1 THEN434 ELSE440 434 FORI=1T01000: NEXTI:H( <8): GOT04068 440 FORI=1 T02000: NEXTI:C-C+1: GOTO7140 640 PEM GOSUB THROU 650 FOR IS 1 TO 5:T(I) = RND(6) : NEXT I 651 GOSUB 16000 660 RETURN 691 PRINT2832. STRING(64.\" \"SPRINT2832,\"DO YOU WANT TO CHANGE ANY NUMBER? 692 X$INKEY 693 IF X GOT0692 \" GOT0692 694 IF X$=\"N\" THEN RETURN EL SEIFXY 695 PRINT2832, \"HOW MANY NUMBERS DO YOU WANT TO CHANGE + + INPUTOHIFK1 ORQ>SGOT06 696 PRINT2832. STRING(64.\" #:ON O GOTO697.699, 701,783.705 697 PRINT2832, \"UHICH NUMBER DO YOU WANT TO CHANGE\"*+ INPUTY 698 GOT0780 699 PRINT3832. \"WHICH TWO NUMBERS DO YOU WANT TO CHANGE\" :: INPUTYS, V 700 GOT0780 701 PRINT2832. \"WHICH 3 NUMBERS DO YOU WANT TO CHANGE\": INPUTYS.WS.K 702 GOT0780 703 PRINT1832. \"WHICH 4 HUMBERS DO YOU WANT TO CHANGE\" : INPUTYS.VY.K$, KK 704 GOT0780 705 FOR 1=1 TOS:T(1)=RND(6) NEXTI: GOTO 903 780 IF Y 'AV=1 790 IF Y=\"B\"=2 800 IFYS=\"C\" 810 IFYDY4 820 IFYEE\"5 821 TCV)ERNDC6): IFQ1GOT0903 830 IFYY \"B\" 2 840 IFWYCHY-3 85@ IFVV$=\"D 4 860 IFW\"EVE 861 TCVY)=RND(6): IFO-260T0903 "


"870 IFK\"C\"23 880 IFKS=\"D\"24 898 IFK=\"E2-5 891 T ZERND (6) IFO360T0903 900 IFKKE=\"224 901 IFKXS=\"E22-5 902 TOZZ) SRND (6) 903 GOSUB16000 $=\"#\": \" KK 920 Y=\"#\": V -:-:20:23 ! 1000 PRINT704. YOUR SCORE 1010 PRINTTAB(25)T(1) TAB(30)T(2TAB(35T63) TAB 40)T(4) TAB(45)T(5) 1820 RETURN 1300 GOSUB 16000 1310 SC=(T(1*103)+(T(2)*1002)+(TC3)*10+T(4) 1320 FOR I=1TOSO: IFINT(SC) INTCK361) THEN1380 ELSE NEXTI 1321 SCOT(2*10[3+ (T3)*10[2)+(T(43*10+T (5) ) THEN1380 ELSE NEXTI 1322 FOR I = 1 TO 3B: IFINT (SC) INT(K 1323 IF AX RETURN WHIC 1330 PRINT2832. STRING(64,\" \"):PRINT3832,\"SORRY !! **2\" YOU MUST SCORE H BOX\"IT INPUT I 1340 IFI6THEN1330 1350 IFXCIX1THEN PRINT2832. STRING(64.\" \":PRINT2832, \"CHEAT !! VOU'VE USED THA T BOX\": FOR I=1 T0500: NEXTI ELSE 1370 1360 GOTO1330 1370 XCI=B: RETURN 1380 IFT(3) THENX(1)3 1381 IFT( 32THENX (216 1382 IFT3) 3THENX(3)=9 1383 IFTC3)=4 THENX(4) 12 1384 IFT(3) 5THENX<5 15 1385 IFT(S)*6THENXC618 1386 RETURN 2000 REM 2011 SCOT(1)*1004+CT(2*1003)+(T(3)*182)+(T 4)*10+T(5) 2021 FORI=1T06: IF INT(SC)=INT VHCI THENALI GOTO2067EL SENEXTI 2031 FORI=1 TO 2: IFINT(SC)=INTCHS (I)) THENAL=3:GOTO2067ELSE NEXTI 2841 FORI=1T014:IFINTCSC)= INTCLSCI) > THENAL+4GOTO2067ELSENEXTI 2051 FOR IT030: IF INT(SC) INT(FHI)) THENAL2: GOTO2067ELSENEXTI THENAL 5: GOTO2067ELSENEXTI 2061 FOR I= 1T030: IF INT(SC) INT(K4(I 2062 SCCT(1*1003)+(T(2)*10C2)+(TC3)*10+T64) 2063 FOR I = 1 T030: IF INT(SC)=INTCKS(ISTHENAL=6:GOTO2067ELSENEXTI 2064 SC=(T(2)*1003)+(T( 3 182)+(T+4)*10+T(5) 2065 FOR T=1T03: IF INT CSC)=INT (KICISTHENAL=6:GOTO2067EL SENEXTI 2066 AL=7 2067 IFAX=1 THEN RETURNELSE ONAL GOTO3030, 308, 3110, 3150.3190.3240, 3298 VAHTZEE \"124: : INPUTI 3030 PRINT2896. \"DO YOU WANT 3040 IF LEFT${I$. 1). \"N\" THEN 3190 305e IF X(14)=1 THEN X(14) = 50 ELSEX(14)XX14)+100 3068 GOTO3351 \"12$: INPUTIS 3880 IFX(11) >1 THEN3240 ELSE PRINT0896. \"DO YOU WANT | FULL HOUSE 3090 IFLEFT*C1, 1)\"N\"THEN3240 ELSE X(11)=25 3180 GOTO3351 3110 IF X(13) THEN 3150 HIGH STRAIGHT\"\"$$:+INPUTI 3120 PRINT 896. \"DO YOU WANT 3130 IF LEFT*CI$ 1) THEN 3150 EL SEX(1340 3140 GOTO3351 3150 IF X(121 GOTO 3290 10W STRAIGHT \"Z$: : INPUTTA 3168 PRINT3896, \"DO YOU WANT 3178 IF LEFT$I. 1)\"N\" THEN 3290 ELSE X(12) 30 3180 GOTO3351 3190 IF XC10> 1 GOTO3240 4 OF A KIND \"25: INPUTIS 3200 PRINT3896. DO YOU WANT 3210 IFLEFTECI. 1).\"NO\" THEN3240 3220 X(10) : FOR INI TO 5: X(10)=X(10) TCI): NEXTI 3230 GOTO3351 3240 IF X(9<>1 GOTO3290 3250 PRINT2896. \"DO YOU WANT 3 OF A KIND . \":21: INPUT I$ 3268 IF LEFTCI$. 1)\"NTHEN 3290 3270 XC9) : FORI=1T05:X(9)X(9) TCINEXT I 3280 GOTO3351 3290 IFX(15) >1 GOTO3340 *Z : INPUTI 3300 PRINT2896, \"DO YOU WANT CHANCE 3310 IF LEFT* 1$. 1) \"\" THEN 3340 3320 X(15) : FOR I=1T05:X(15) X(15)+TI: NEXT 3330 GOTO3351 ZERO\"? WHICH BOX\": 1 INPUT I 3348 PRINT2896, \"SORRY \"+251\" YOU MUST SCORE 3341 IF 1 90RI > 15 THEN3340 3350 XC) 3351 RETURN 3700 PRINTO, \"COPYRIGHT K. HOOK 3. BULCOCK STREET, BURNLEY, 57427 3705 FOR IS 1 TO 1000: NEXT:CLS YAHTZEE ** 3710 PRINT448. \"THIS IS THE GAME OF 3715 PRINT2512.\"IT IS BASED ON MILTON BRADLEY LTD' VERSION OF THE RULES.\" 716 FOR I = 1 TO 1800: NEXT 3720 PRINT2832,\"PRESS NEW LINE) TO CONTINUE.....\": INPUT 3725 CLS: INPUT DO YOU NEED INSTRUCTIONS........\" 3730 IF LEFT$I$.1 \" GOTO3810 3735 IF RIGHTI$, 1)) THEN 3225 3740 CLS:PRINT0512, TAB(18) \"V AHT ZEE 3745 PRINT2896. \"THE RULES WILL FOLLOW.... 3758 FOR 1-1 TO 500: NEXT I 3751 CLS:PRINTOS. TAB (18) VAHT ZEE 3755 PRINT THE OBJECT OF THE GAME IS TO OBTAIN THE HIGHEST SCORE. 3760 PRINT\" THE PLAYER WITH THE HIGHEST TOTAL SCORE WINS.\" 3765 PRINT\"YOU ARE PLAVING AGAINST THE COMPUTER, BUT THE COMPUTER WILL 3770 PRINT\"KEEP AN EVER WATCHFUL EVE ON YOUR MOUES. IT WILL NOT LET YOU\" 3775 PRINT\"CHEAT.\" 3789 PRINT \"THE SCOREBOARD IS DIVIDED INTO TO HALDES LEFT AND RIGHT. 3785 PRINT VOU ARE ALLOWED THREE THROUS IN ANY ONE GO AND THE POINTS\" 3798 PRINT AWARDED ARE SELF EXPLANATORY.\" 3795 PRINT** FULL HOUSE IS :-11155ETC.\" 3796 PRINT:PRINT 1800 PRINTPRESS NEW LINE TO CONTINUE... \"INPUTU 3810 CLS:PRINT3512. \"WHAT IS YOUR NAME\" : INPUT 2 3815 CLS:PRINTO448. THANK YOU \"+2+ 3828 PRINTO512. TAB(20) \"MY NAME IS GEAN 3825 FOR ITO 1000: NEXT 3830 VS=\"THIS YOUR SCORE CARD \"GOTO340 X -DO YOU WANEN 3290NEXT I "


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Upper and lower case  True Descenders  Bi-directional Paper Mode  Underlining capability Condensed/Expanded Print Sub-Scripts and Super Scripts  Pin and Friction Feed. 80/132 Column 739 as above with special feature of Dot Resolution Graphics. NOW INCLUDED: Sound, Upper and lower case, Extended BASIC and Machine Code enabling the Writing and Execution of Machine Codes Programming direct from Keyboard 16K RAM 12K Microsoft BASIC Extensive Software Range Self-Contained PSU UMF Modulator Cassette External Cassette Interface. Simply plugs into TV or Monitor Complete and Ready to Go Display is 6 lines by 32 or 64 Characters Switchable 3 Mannuals included Users Guide Beginners Programming and BASIC Reference Mannual BASIC Program Tape Supplied Pixel Graphics  THE ANADEX DP9500 and DP9501 A PROFESSIONAL PRINTER GENIE 11 GUARANTEE BY .Bi-directional printing .Up to 220 chars/line with 4 print densities .500 char buffer  RS232C and Centronics Parallel interface built in Full software control of matrix needles allowing graphics capability  200 chars/sec  Adjustable width tractor feed DP9500 ONLY  VAT DP9501 ONLY  + VAT NEC SPINWRITER only  + VAT NEC's high quality printer uses a print thimble that has less diameter and inertia than a daisy wheel, giving a quieter faster, more reliable printer that can cope with plotting and printing (128 ASCII characters) with up to five copies, fric tion or tractor fed. The ribbon and thimble can be changed in seconds. 55 characters per second bidirectional printing with red/black, bold, subscript superscript proportional spacing, tabbing, and much, much more. NOBODY CAN GET NEAR OUR PRICES EXCEPT OUR CUSTOMERS E299 VAT The NEW GENIE I an ideal Business Machine 13K Microsoft BASIC in ROM 71 Keyboard. Numeric Keypad Upper & Lower Case Standard Flashing Cursa Cassette Interface 16K RAM Expanded externally to 48K WE ARE NOW STOCKING THE APPLE II AT REDUCED PRICES AUTOSTART EURO PLUS 48K  GENIE I & II EXPANSION UNIT WITH 32K RAM  VAT PARALLEL PRINTER INTERFACE CARD 35 0 VI OMPUSAS VAT HITACHI PROFESSIONAL MONITORS 9''  .95) 12'' 189  VAT . Reliability Solid state circuitry using an IC and silicon transistors ensures high reliability 500 lines horizontal resolution Horizontal resolution in excess of 500 lines is achieved in picture center.  Stabla picture Even played back pictures of VTR can be displayed without jittering  Looping video input Video input can be looped through with built-in termination switch. External sync operation available as option for U and C types)  Compact construction Two monitors are mountable side by side in a standard 19 inch rack Getting Started APPLE Iis faster smaller and more powerful than its predecessors. And it's more fun to use too because of built in features like .BASIC The Language that Makes Programming Fun High Resolution Graphics in a 54,000 Point Array) for Finely Detailed Displays Sound Capability that Brings Programs to Life Hand Controls for Games and Other Human Input Applications Internal Memory Capacity of 4BK Bytes of RAM, 12K Bytes of ROM for Big System Per formance in a Small Package Eight Accessory Expansion Slots to let the System Grow With Your Needs You don't need to be an expert to enjoy APPLE II It is a complete, ready to run computer Just connect it to a video display and start using programs for writing your own the first day. You'll find that its tutorial manuals help you make it your own personal problem solver TEAC DISK DRIVES NEW ACORN ATOM UNIQUE IN CONCEPT THE HOME COMPUTER THAT GROWS AS YOU DO Fully Assembled .50 VAT inc. PSU TEAC FD-50A has 40 tracks giving 125K Bytes Unformatted single density capacity  The FD-50A can be used in double density recording mode The FD 50A is Shugart SA400 interface compatible  Directly compatible with Tandy TRSBO expansion interface Also interfaces with Video Genie, SWTP TRS80 North Star Horizon Superbrain, Nascom etc, etc Address selection for Daisy chaining up to 4 Disks  Disks plus power supply housed in an attractive grey case 40 TRACK Single Disk Drive -VAT E389 + VAT 77 TRACK Single  VAT Double  VAT Disk Drive LOS Disk Drive APPLE DISC II 3.3 Dos Disc with Controller E389 + VAT Additional Drives F289 + VAT  Powerful Disk Operating Software Supports up to 6 drives Name Access to Files for Ease of Use .BASIC Program Chaining to Link Software Together Random or Sequential File Access to Simplify Programming Dynamic Disk Space Allocation for Efficient Storage Individual File Write Protection Eliminates Accidental File Alterations Loads an BK Byte Binary Image in 6.5 sec (12 sec in Pascall . Storage Capacity of 116 Kilobytes (143K Bytes with Pascall on Standard 5% Diskettes Powered Directly from the APPLE TUp to 6 Drives for Convenience and High Reliability Packaged in Heavy Duty, Colour Coordinated Steel Cabinet Colour Monitors for Apple 296 + VAT TENDED Special features include  Full Sized keyboard . Assembler and Basic Top Quality Moulded Case  Optional High Resolution Colour Graphics 6502 Microprocessor SALE 4K FLOATING POINT ROOM 19.50 + VAT  coi 0UR ENCODER E19,00 + VAT Step We give a full one year's guarantee GHWUCNEE on all our products, which normally only carry 3 months guarantee. MEMORY UPGRADES S 16K (8 x 4116) .90 +VAT 4K Compukit (8 x 2114) .90 .VAT LUXOR 14\" COLOUR MONITOR FOR THE APPLE  + VAT A SELECTION OF APPLE INTERFACES ARE NOW AVAILABLE AT OUR EDGWARE ROAD SHOWROOM WE HAVE ONE OF THE LARGEST COLLECTIONS OF COMPUTER BOOKS UNDER ONE ROOF, ALONG WITH SOFTWARE FOR THE GENIE, TRS80 AND APPLE. 58 COMPUTER & VIDEO GAMES "


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KIT ONLY .95 +VAT Fully Assembled  + VAT PLUS 14.50 Post Packing snr Build, Understand and Program your own Computer for only a small outlay 48K  + VAT The Radio Shack TRS 80TM Model ill is a ROM-based computer system consisting of A 12 inch screen to display results and other information  A 65 key console keyboard for inputting programs and data to the Computer . AZ 80 Microprocessor, the brains of the system A Real Time Clock Read Only Memory IROMI containing the Model II BASIC Language fully compatible with most Model I BASIC programs) Random Access Memory (RAMI for storage of programs and data while the Computer is on amount is expandable from 16K to 48K\" optional extra). A Cassette Interface for long term storage of programs and data (requires a separate cassette recorder, optional/extral. A Printer Interface for hard copy Output of programs and data frequires a separate line printer, Optional/extral Expansion area for upgrading to a disk based system (optional/extral Expansion area for an RS 232 C serial communications interface (optional/extra) All these components are contained in a single moulded case and all are powered via one power cord Disc Drives Kit with 2x 40 Track Drives 599 + VAT Disc Drives Kit with 2x80 Track Drives  +VAT NEW MONITOR IN ROM available separately at .90 +VAT Improved BASIC 3 ROM revised GARBAGE routine allows correct use of STRING ARRAYS E4.90 This chip can be sold separately to existing Compukit and Super board users 4K Upgrade Kit VAT .90 FOR THE COMPUKIT Assembler Editor .90 Case for UK 101 29.50 GAME PACKS 11. Four Games .00 21. Four Games .00 Super Space Invaders (8K) .50 Chequers .00 Realtime Clock .00 10 x C12 Cassettes .00 40 pin Expansion Jumper Cable .50 All Prices exclusive VAT CASIO VL TONE 0.25 VT GLIARANTEE BY EXTENDED A TUTTI GUARANTEE BY Q0D SHARP PC1211 .95 + VAT COMPUTER POWER THAT ONCE FILLED A ROOM CAN NOW BE CARRIED IN YOUR POCKET!  Programs in BASIC \"QWERTY\" Alphabetic Keyboard .9K Random Access Memory  Long Battery Life. BEEL ELEE FECE FREE It's a new kind of musical instrument A computer controlled Synthesiser that helps you create play and arrange composi tions that normally take years of music training Also a calculator YOUR ZX80 IS NOW NO LONGER REDUNDANT Upgrade your ZX80 to the full animated graphics of the ZX81. (No screen flicker FOR ONLY .95 + VAT IN KIT FORM Works only in conjunction with NEW 8K ROM from Sinclair (Not Included) OUR NEW SUPER LOCATION IN IRELAND 19 Herbert Street, Dublin 2. 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Music in three voices and three octaves  Language and sound effects  + VAT  4 Mhz 2-80CPU. Dynamic RAM 2K ROM. BASIC is provided High Resolution Graphics  9\" High Focus Green Display Upper and Lower Case  80/40 Characters x 25 line display  Electro Magnetic Cassette Deck included ASC11 Keyboard  Numeric keypad . Sound Output  Built-in Clock and Music Available Soon-Discs, Printers and other Accessories BBC COMPUTER Please phone for availability and price Delivery is added at cost. Please make cheques and postal orders payable to COMPSHOP LTD., or phone your order quoting BARCLAYCARD, ACCESS, DINERS CLUB or AMERICAN EXPRESS number MAIL ORDER AND SHOP: CREDIT FACILITIES ARRANGED send SAE for application form 14 Station Road, New Barnet, Hertfordshire, EN5 10W (Close to New Barnet BR Station Moorgate Line) Telephone: 01 441 2922 (Sales) 01-449 6596 Telex: 298755 TELCOM G TELEPHONE SALES OPEN (BARNET) -10am 7pm Monday to Saturday NEW WEST END SHOWROOM: OPEN 24 hrs. 7 days a week 311 Edgware Road, London W2. Telephone: 01-262 0387 01-449 6596 OPEN (LONDON) 10am Epm Monday to Saturday LANCA CARD IRELAND: 19 Herbert Street, Dublin 2. Telephone Dublin 604165 VISA COMPSHOP USA, 1348 East Edinger, Santa Ana, California, Zip Code 92705 Telephone 0101 714 5472526 \"Europes Largest Discount Personal Computer Stores\" COMPUTER & VIDEO GAMES 59 "


"4068 PEM 4069 IFH(7)=1 THENFOR 1=1T06:H(7)H7)+HI: NEXTI 4078 IFH(8)=1 THENFOR I =9T015:H(8)H(8)+H INEXTI:HCSHC8H07) 4098 IFCP=1 THEN FORT=1T06:CP (7) CP(7)+CP (I): NEXTI 4108 IFCP (8) = 1 THENFORI=9T015:CP (8)=CP(8)+CPCI): NEXTI:CP (8)=CP (8)+CP (7) 4128 CLS:PRINT3448. TAB20) \"YOUR SCORE \"Zt. H(8) 4138 PRINT2512. TAB(20) \"MY SCORE \"ZI.CP.8% 4139 FORI=1 TO2000: NEXTI 4148 IFCP(8) H(8) THENBE.\"I'UE LION !! \" ELSEBETYOU'VE WON THIS TIME! 4158 CLS: PRINT0512, TAB(20) B$+26: FOR 1=1 T01000: NEXTI:CLS 4178 PRINT0512, \"DO YOU WANT ANOTHER GAME\":2! 4188 INPUTI$ 4198 IFLEFTI$.1 GOTO 340 4208 IFLEFT*CI, I N GOT04178 4218 CLS:PRINT3512,\"0. K. CHICKEN!!\": FOR I = 1 TO 5eet NEXT 4228 CLS:PRINTaS12, \"GOODBYE\" :FOR I 1 TO 1800: NEXT:CLS 4238 END 7000 VS \"THIS IS MY SCORE CARD...... 7010 GOSUB 140 7020 PRINTa640,\"IT'S MY THROW \"+2; 7830 PRINT TAB(26) \"A B C D E 7040 IF CMOGOT07080 2050 FOR X = 52T089:FOR X1=52T089STEP3 7860 SETCX, 34): RESET CX1.34): NEXTX1, X 7070 FORX52T091 : RESET(X.34): NEXTX 7080 PRINT 704, \"MY SCORE \"+ 251 7090 PRINTTAB(25) T(1): TAB(30)T(2): TAB(35)T(3): TAB(40)T(4) TAB(45)T(5) 7091 PRINT2832, STRING64.\" 7108 RETURN 7140 CM : CC1: T=0:AX=1: IFC 1 THEN7160 2150 FORI1T015: XCI)1HEXTI 7160 FORIS1T015:XCI) CPI NEXT I 7170 GOSUB640: GOSUB16008: GOSUB7000 7180 CM=1:T=T+1 7181 PRINT2832, \"I'M THINKING \"ZT:FORI+1T01000: NEXTI 7182 GOSUB 2880 7187 ON AL GOT07190.7220.7270, 7290.7385,7365.7435 7190 IF X(14) = 1 GOTO 30780 7195 IFX(10)=1 GOTO 30780 2200 IFX(9)=1 GOTO 30800 7205 IF X(9)<>1 AND X18X1 ANDX(12) >1ANDX(13) 1GOTO 30700 7210 BEAS 7215 GOTO30200 7220 REM FULL HOUSE 7225 IFX(11=1 GOTO 30760 7230 IFX(9)=1 GOTO 30800 7235 IF T(1)=T(3) THEN WET(1) 7240 IFXCW)=1 GOTO 7500 7245 IF T(5)=T(3) ET (5) 7250 IFXCW)=1 GOTO 7500 7255 IFT(1) T(3) B$=\"D & E7260 IFT(5) T(3) B$=\"A & B 7265 GOTO 30200 7270 REM 7275 IFX(13)*1 GOTO 30720 7280 IFX(12)=1 GOTO 36740 7285 GOTO 30509 7290 REM 7295 IF X(12)= 1 GOTO 30740 7300 GOTO 8009 7305 REM FOUR OF A KIND 7310 IFX<10)1 60T030780 7311 IFT=STHEN7315 7312 IFX(14)*1 ANDTCIT(4) B EELSEBETA\":GOTO30208 7315 IFX(9)=1 GOTO 30800 7320 IFT(I)=T(4) THEN IT (1) 7325 IFXCW)=1 GOTO 7500 7330 IFT(5)=T(2) THEN WET(5) 7335 IFXCW) = 1 GOTO 7500 7340 IFX(11)=1 GOTO7350 7345 GOT07488 7350 IFT(1) T(4) BED & E # 7355 IF T(5) ET (2) BWA&B 7360 GOTO30200 7365 REMS OF A KIND 7370 IF X(9)=1 GOTO 30800 7375 IFT(1) T(3) THENT(1) 7380 IF X(W) =1 GOTO 7500 7385 IFT(5)=T(3) THEN WET(5) 7398 IFXCW)=1 GOTO 7500 7395 IFT (2)=TC4) THEN WTC4) 7400 IFXCW=1 GOTO 7500 7405 IFX(11)=160T07420 7410 IFXC10 )=1 GOTO7420 7411 IF T T (3B\"ABC\" 7412 IFT<5)T(3) B CDE 7413 IFT(2)=T(4) BOD\" 7414 GOTO 38200 7420 IFTCIT (3) B D & e 7425 IFT(ST3) BATA EBH 7430 IFT(2)=T(4) B#=\"A&e.\" 7431 GOTO30280 7435 PEM CHANCE 7440 X=@: IF T<>3 GOT07450 7445 IFX(15)=1 GOTO 30821 ELSE 7550 7450 FOR I9T014: IFX(I) THEN X=X+1 EL SENEXTI 7455 IF XH ANDX(15) GOTO 30821 ELSE 30509 7480 REM CHANGE ALL DICE 7485 IFT-3 GOTO_755@ELSEPRINT2832, \"I'M CHANGING ALL THE DICE\":25 7490 FOR I TO 5:T(I)ERND (6) INEXTI 7495 GOSUB16000: GOSUB7080: GOT07188 7500 (W)= REM LEFT SSCRCRD 7505 ON XOW GOTO 7510,7515,7520,7525, 7530 7535 7510 X(1)=3:B$\"ONES\":GOTO7540 7515 X<2)=6: B TWOS\":GOT07540 7520 X(3)=9:B$\"THREES\":GOT07540 7525 X(4)=12:B \"FOURS\":GOTO7540 7530 X<5>= 15:B=\"FIVES\": GOTO7540 "


"7535 XC6) 18:01SIXES\":GOTO7540 7540 PRINT1832. \"I'M GOING LEFT \"Z$:\" INTO \"$B$:FOR I=1T05@G: NEXT 7545 GOSUB7000:GOTO 30840 7550 REMZERO 7555 PRINT2832, \"i'LL HAVE TO SCORE ZERO THIS TIME \"2 7560 FOR I = 1 TO 6: IF XCD) THENXCI) :GOTO30840 ELSE NEXT I 7565 FOR I=9TO 15: IFX(I) THEN XI) : ELSE NEXT I 7578 GOTO30840 8089 REM DATAONE 8010 IFX(13)<>1 GOTO8016 8011 IFT(1)T(2) B \"A\":GOT08021 8012 IFT(2)=T(3) B$\"C\":GOT08021 8013 IFT(3) T(4) B D\":GOTO8021 8014 IFT(4) T(5) BEE\":GOT08021 8015 GOT07480 8016 IFT(2)T(3) B ADE \"GOTOB021 8017 IFT(3) T(4) B ABE \"GOTO8021 8018 IFT(4) T(5)B \"ABC\":GOTO8021 8019 IFT(1)T(2) B CDE\":GOTO8021 8828 GOT07488 8821 GOTO38280 15800 IFXC7><>1 GOTO15086ELSEFORI=1T06: IFX )=1GOT015806 ELSE HEXTI 15601 A1B:FOR IT06IARRAREXCI): NEXTI 15082 IF AR-16 GOTO15006 15803 X(7) : FORI1T06:X(7)X(7) +X(I): FOR J=1T010 15094 PRINT2448. \"TOTAL (IF 63 +35)\": TAB(23)X(7): NEXTJ. I 15605 IFX(7)*63 THEN((7) 985 15006 IFXC8/ 1 RETURNELSE FOR I=9T015: IF XCD)=1 THEN RETURN ELSE NEXT I 15007 FF-10: FORI=9T015:FF:FF-XI) INEXTI 15008 IF FF-16 RETURN 15889 X(8) :FOR *9T015+X(8)*(8)+X(I) FORJ=1T018 15010 PRINT0512, \"GRAND TOTAL LEFT PLUS RIGHT)....... ......\":TAB(59)X(8): #NEXTJ-I 15811 IFXC7><>IANDX(8)<>1 THENX(8)=X(8)+X(7): FORI=1T01980: NEXT I 15812 RETURN 16000 FORITOS+FORV2TOS 16810 IPTV THEIGHT 1620 TV TIV-IV-22 16038 NEXTY 16040 NEXTX 16050 RETURN 30000 K=k+11 IFK< >I RETURNI DATA 11235.11236 38018 FORI=1T02: READ J(I) NEXT 38020 DATA11223. 11224. 11225. 11226.11334. 11335, 11336. 11445, 11446. 11556 38821 DATA11226. 11336.11446, 11556.22336.22446.22556.33446.33556, 44556. 24566.3456 623566.13466.14566. 13455, 12455. 12356 30030 FORI=1T028: READJJCI) INEXTI 30040 DATA11233, 11244.11255, 11266.11344.11355, 11366.11455, 11466 30050 DATA11566, 22344, 22455, 22355, 22366,33455,33466,33566,44566 30068 FORI=1T018: READKCI) NEXTI 30078 DATA12235, 12236, 13356.23356, 23346.24456 30880 FORI=1T06: READKKCINEXTI 30898 DATA12233, 12244.12255, 12266, 13344, 1335513366, 14455, 14466 30100 DATA15566.23355, 23344,23366.24455, 24466,34455,35566.45566 50110 FORI=1T018: READL(I): NEXTI 3014 RETURN 30120 DATA12355, 12356, 12366.23566,23556 30200 REM RETHROW 30130 FORI=1 TOS: READLLCI INEXTI 30201 IF T3 GOT07550 30131 DATA11332, 11335, 11334.11336, 11226, 11225, 11224,11223 30210 2(1) RND(6):262)RND(6): Z(3)-RND(6) 30132 DATA22334,22335.22336, 33446,33445.44556 30220 IF B$=\"A\" T(I)*2(1):GOTO38350 30133 FORI=1T014: READMCI): NEXT 30238 IFB-\"C\"T(3)=2(1): GOTO30350 3@240 IFB:\"D\"T(4)2(1): GOTO30350 38241 IFB$=\"B\"T2)=2(2): GOTO30350 30250 IFB:=\"E\"T<5)2(1): GOTO30350 38251 IFBB & E T (2)2(2):T(5)=2(3)GOTOJ@350 38260 IFB$=\"CDE\" T(3) Z(3)T(4)2(2):(5)2(1) 1 GOTO30350 30261 IFBB CD \"T(2)2(1): T(3)2(2):104)23) GOTO30350 56278 IFB$=\"ADE \"T(1) Z(1): T(4)*22)T(5)=2(3)+GOTO38350 30280 IFBA BE \"TCI)2(1) T(2Z<2)T(5) Z(3) GOTO30350 38290 IFBE \"ABC\"T(1)=2(1):T(2)Z(2)T(3) 2(3)+GOTO38350 30380 IFBA & B \"T(1)=2(1)T(2) Z(2) GOTO30350 38310 IFB:\"D & \"T(1)=2(1):T(5) Z(2): GOTO38350 30311 IFE A & C \"T(1) Z(1) T(3) 2(2). GOTO30350 36312 IFB$=\"ATE \"T(1)=2(1):7(5)Z(2) 50350 PRINT2832. \"I'M CHANGING \"1851\" \"1Z5IFOR 1-1 T010001NEXTI 30351 GOSUB 1602B: GOSUB7080GOTO7180 30509 REM DATA SORT 30510 SCOT(I*10[4+(TC2)*10[3)(T(3)*1002)+(TC4) 10)T(5) 30580 IFT<>SGOTO30590 30520 FORI=1T02: IFINT(SC)=INT(JCI) >GOTO30580EL SENEXTI 38581 IFX(15)<>1 GOT07550 EL SE30821 30530 FORITO101IFINT SCINTJJCI >> GOTO30600 ELSE NEXTI 30590 B TA\"GOTO30200 38540 FORITO18: IF INT(SC) INT(KCI>) GOTO30610 ELSE NEXTI 30660 BS=\"E\":GOTO38288 30550 FOR IT06IFINT (SC)INT (KKC6)GOTO30620 EL SE NEXTI 30610 B=\"C\":GOTO38280 3856B FORI=1T018: IF INT<SC) INT(LI) GOTO38590 E LSE NEXTI 30620 B B\":GOTO30200 38570 FORI=1T05: IF INT(SC) INTCLLCI >> GOTO 30600 ELSE NEXTI Case E5*à 1 * BT00206 30571 FORI=1T014; IFINT(SC) INTCM(I)1 GOTO30630 30631 GOTO30280 58700 IFX(14) THEN X(14)-50 ELSEX(14)=X(14) +100 30710 PRINT0832.\"I'M GOING FOR YAHTZEE !! \":25:GOTO30840 30720 X(13)-40 38730 PRINT0832, \"i'M IN FOR HIGH STRAIGHT \"ZE:GOTO30840 30740 x1230 50758 PRINT2832, \"i'VE GOT LOW STRAIGHT THIS TIME \" Z5:30T038840 30760 X(11)=25 30770 PRINT2832, \"FULL HOUSE \"+Z$:\" I'M PLEASED ABOUT THAT!\":GOTO30840 30788 X(10) O:FORI1T05:X(10)=X(10)T(I)NEXTI 30798 PRINT3832, \"MANAGED FOUR OF A KIND \"+ Z5: GOTO38840 30800 XC9) : FOR I1T05:X(9)X(9)+T(I) NEXTI 3e810 PRINT2832, \"THREE OF A KIND \"ZU: GOTO30840 30820 IFX(15) >1 GOTO30831 30821 X(15) O:FORT1T05:X(15)X(15)+TI) NEXT 58838 PRINT832,\"PHEW !! JUST MADE CHANCE THIS TIME ZS:GOTO30840 38840 FOR I=1 TO 1000: NEXT IHREM END BIT 3885@ GOSUB7000: GOSUB15000 38860 IF X<><>1 AND 8)<>1 THENCP (8)X(8): GOT04868 30870 FORI=1 TO 15:CPI (I) NEXTI Saeeo FORINT01000: NEXTI 50890 AX : #33CC3089: YST \"THIS IS YOUR SCORE CARD 38900 GOTO369 "


"By TED BALL PRACTICAL PRACTICAL PRACTICAL REE PROGRAMMING SY TED BALL MANIPULATING YOUR DATA Lines 220 and 230 give D equal to the remainder after dividing NI by 16; which is the value of the rightmost digit in the hexadecimal form. Lines 240 and 250 give A equal to the ASCII code for D. In the ASCII code the digits 0 to 9 are coded as the numbers 48 to 57, and the letters A to Z are coded as 65 to 90; thus adding 48 to D gives the correct ASCII code if 0<=D<=9, but if 10<=D<= 15 it is necessary to add another 7 to get the ASCII code for a letter from A to F. This method is machine. dependent, as it makes use of specific ASCII codes, and while it will work on most home computers it will not work on all of them. The Sinclair machines, for example, do not use the ASCII codes. However, it is easy to convert the program so that it does not depend on the particular code used to represent the characters. If we add 10 LET C$ = \"0123456789ABCDEF\" An important part of designing a program is deciding exactly how data is to be represented and organised The same data may be represented and organised in many different ways, and a particular form will allow some operations to be performed more easily than others. For example, arithmetic of any kind is very difficult with Roman numerals, but much easier with modern positional notation, and in positional notation the choice of base makes a difference to some operations. The simplest and best known example is the way in which we can multiply or divide by 10 in base 10 by shifting the digits left or right relative to the decimal point, while in base 2 the same operations give a multiplication or division by 2. A less familiar example is found in tests for divisibility. Some commonly used tests are that a number is divisible by 2 if its last digit is divisible by 2, divisible by 3 if the sum of its digits is divisible by 3, and divisible by 9 if the sum of its digits is divisible by 9. However, these tests rely on the number being written in base 10 and will not necessarily work if the number is written in any other base; for example 9 in base 3 is 100 and none of the tests works in this case. Character sets in computers vary in the number of characters available, the graphics characters included, and the internal code used to represent the characters. For many purposes it is not necessary for the programmer to know the internal code since high-level programming languages usually provide functions for converting from code to character and vice versa. In Basic the commonly used 62 COMPUTER & VIDEO GAMES functions are ASC (\"x\") or CODE (\"x\") which gives the code for the character x, and CHR$(N) which gives the character correspond ing to the code number N. In some machines the same code gives different results according to how it is used; for example, on the PET PRINT CHR$ (N) and POKE S N where S is a location on the screen, do not generally produce the same character. In programming it is always best to use methods that do not depend on special features of the machine, as this will make your programs easily transportable. The following program for converting numbers to hexadecimal (base 16) demonstrates a method that is often used for calculating the character code corresponding to the digits of a hexadecimal number. 100 PRINT \"DECIMAL NUMBER\": 110 INPUT N 200 LET NI = N 210 LET H$=\" 220 LET Q = INT (N1/16) 230 LET D = NI 16*Q 240 LET A =D + 48 250 IF A > 57 THEN LET A = A + 240 LET H$ = MID$ (C$, D +1, 1) + H$ and delete lines 250 and 260 the program will work on any machine with Microsoft Basic regardless of the character code used. It still will not work on a Sinclair ZX8l as Sinclair BASIC does not have the MID$ function. However, in Sinclair Basic line 240 can be replaced by 240 LET H$ = C$(D+1) + H$ DEFINING CODES . . . What we are doing in the second method is, in effect, defining our own code so that the code used in the machine is irrelevant to the working of the program. In most applications we have to define our own representation for the data because the machine does not provide exactly what we want. As an example, consider the problems of representing playing cards in a program. Some home computers have graph symbols for the suits but others do not; in the latter case we can 260 LET H$ = CHR$ (A) + H$ 270 IF NI < 16 THEN GOTO 300 280 LET NI = 0 290 GOTO 220 300 PRINT N; \"IN DECIMAL IS\"; H$; \"IN HEX\" 310 GOTO 100 "


"use the letters C,D,H, S, as easily remembered abbreviations. A card-playing program will have to accept cards input from the keyboard, perform various operations on the cards, and display cards on the screen, and these three phases may require entirely different representations of the cards and hence require conversion between the different representations. For example a card may be typed in as CA, held as the number 14 for calculations concerning the play, and displayed on the screen as a picture of the Ace of Clubs. The programmer will have little choice in the input and output forms as these must be easily recognised by the user, but the internal form may be chosen in many ways differing in both representation and organisation. The choice of an internal form suitable for the operations that must be carried out can make a great difference to the ease or difficulty with which the program is designed and coded. STORING CARDS ... If the program began by deal we want the hand sorted with ing the player's hand we must cards of the same rank together also check that the card he typed regardless of suit we define in was included in the hand he P$(1)=\"CA\", P$(2)=\"DA\", was dealt. P$(3)=\"HA\", P$(4)=\"SA\", On exiting the above routine I P$(5)=\"C2\", etc. points to the array element cor In many card games we will responding to the card typed in, need to separate the suit and which with P$ as defined means value of a card, and possibly that the cards are coded as perform some manipulations CA=1, C2=2, etc. with the value. This simple method of obtain If we store the cards in an ing a numeric code may be all array such as P$ the suit can be that is needed for some pur found easily as S$ = LEFT$ poses. For example, to sort a (P$(I), 1) and a numeric code can hand we can simply sort the be devised from this if necescodes into ascending order and sary. when we convert the codes to It is usually more complicated strings by looking up the P$ to deal with the rank or value of array we will find all cards of the the cards; it is rare to find a card same suit together and in order game that requires any operafrom Ace low to King high. tion on the suits other than orderOther orders can be catered for ing or testing for equality, and by defining P$ differently. If we sometimes for colour. However, want the cards sorted into suits different card games require a and in order from two low to Ace wide range of operations to be high we define P$(1) =\"C2\", carried out on the ranks or valP$(2)=\"C3\", ..., P$(12)=\"CK\", ues of the cards and there are P$(13)=\"CA\", P$(14)=\"D2\", ...; if | frequently special cases. GAMES YOU CAN PLAY If we look at a few games we the highest total without going can see some of the necessary over 21, where 2 to 10 count as operations and special cases the spot value, J,Q, K count 10, that affect the suitable represenand A may count as either 1 or 11 tations of the cards. as the player wishes. In evaluatCRIBBAGE ing a hand it is necessary to allow for the two different values Points are scored for cards in that may be assigned to an Ace. sequence, with 10, J,Q,K entering into sequences in that order, BRIDGE so it would appear that these In the bidding the suits rank cards can be given a value of 10, from low to high, Clubs, 11, 12, 13 respectively. However, Diamonds, Hearts, Spades, No points are also scored for combiTrumps. In the play, however, nations of cards totalling 15 and there may be a trump suit, in in this case 10, J, Q and K all which case a card of the trump count as 10. Thus we need a suit ranks above cards of any different representation for J, Q. other suit whenever it is played K according to what we are in a trick. To allow for this we doing. need a valuation of the cards POKER that may change from hand to hand. A run of five cards may have Where we have a straightforan Ace as the high card or the ward ordering of the cards in a low card, but cannot have an suit, whether from Ace low to Ace in the middle. Thus, A, 2, 3, King high as in Cribbage, or 4, 5 and 10,J,Q,K, A count as from two low to Ace high as in runs, but J. Q, K, A, 2 does not. Bridge, it is possible to calculate However, elsewhere in the game the rank of a card from its posiAce is always high. Probably the tion in the P$ array. easiest way of dealing with this anomaly is to include a special For example, using the third test for runs of the type A, 2, 3, 4, definition of P$ above, LET R = INT( (I +3) 14) would give R the value 1 when I was 1, 2, 3 or 4 BLACK JACK (i.e., for an Ace), 2 when I was 5. The aim of the game is to get 6, 7 or 8 (i.e., a Deuce), etc. One method of storing cards which simplifies many operations is to use a string array in which the array elements are the input forms and the array indices are used either as numeric codes for the cards or as pointers to another array giving numeric codes. For example, we could define a string array P$(52) with P$(1)=\"CA\", P$(2)=\"C2\", ..., P$(13)=\"CK\",P$(2)=\"DA\", ..., P$(52)=\"SK\". We can then use a simple routine to check that what the player has typed in is actually a valid card: 100 INPUT C$ 110 LET I = 1 120 IF C$ = P$(I) THEN GOTO 200 130 LET I = I +1 140 IF I< 53 THEN GOTO 120 150 PRINT \"NOT A VALID CARD, TRY AGAIN\" 160 GOTO 100 200 COMPUTER & VIDEO GAMES 63 "


"-FULLER FD SYSTEM FOR ZX80/81 THE MOST VERSATILE SYSTEM FOR EXPANDING YOUR ZX STANDARD KEYBOARD AND CASE Fuller IIIIIII TTTTTTTTT TTTTTTTTTT This splendid keyboard and case houses your ZX81 printed circuit board, which is simply screwed into place, the keyboard plugs into the ZX. You can now enter data with ease. The 40 key switch board is a custom unit not made up out of other manufacturers parts. The keytops are our own design and have the ZX Qwerty and functions foil printed onto them. Access to the user port, TV, MIC, and ear sockets are as per the ZX case. Built keyboard and case .70 or .70 as a kit plus .10 postage and packing EXTENDED KEYBOARD AND CASE The case is designed to house not only the keyboard and ZX but also our motherboard, power supply, RAM cards and two other boards, not necessarily of our manufacture. The injection moulded case measures 200 mm x 350 mm x 60 mm and houses a 42 keyswitch board, the extra keys can be assigned to other functions. The case is supplied with a \"'Power On\" LED. Fuller Built keyboard and case .95 or kit .95 plus .50 postage and packing. Motherboards .95 plus 80p postage and packing. 16k RAM board .95. 64k RAM board .95. Keyboard Only Available! Built .95 Kit .95 (+P.P.80p) Send SAE for details to:FULLER MICRO SYSTEMS, The Zx Centre, Sweeting Street, Liverpool 2. The Essential Software Company Not Only 30 Programs for the Sinclair ZX 81:1K ESSENTIAL ZX81   30 PROGRAMS SINCLAIR Not only over 30 programs, from arcade games to the final challenging Draughts playing program, which all fit into the unexpanded 1K Sinclair ZX 81 but also notes on how these programs were written and special tips! Great value! Understanding Your ZX 81 ROM A brilliant guide for more experienced programmers by Dr. lan Logan, this book illustrates the Sinclair's own operating system and how you can use it. Includes special section on how to use machine code routines in your BASIC programs. The Complete Sinclair ZX 81 BASIC Course At last, a comprehensive text for your Sinclair ZX 81! The complete BASIC Course is a manual which will immediately become an indispensible work of reference for all your ZX 81 programming Order Form: Machine Language Programming Made Simple for the Sinclair A complete beginner's guide to the computer's own language Z80 machine language. Machine language programs enable you to save on memory and typically give you programs that run 10-30 times faster then BASIC programs Sinclair ZX 81 ROM Disassembly by DR. I. LOGAN. The definitive book for the programmer that needs those answers about the Sinclair ZX 81 ROM. Orders to The Essential Software Company, Dept BT (Visconti Ltd.) 01 837 3154 47 Brunswick Centre, London WCIN 1AF .50 NAME The Complete Sinclair ZX 81 BASIC Course .50 DI Basic Course Programs on Cassette Sinclair ZX 81 ROM Disassembly Part A-0000H-OF54H  7.000 Not Only 30 Programs/Sinclair * ZX 81:1K  6.95 Machine Language Programming Made Simple  8.95 O ... Understanding Your ZX 81 ROM  8.95 ! Postage and Packing  0.70 1 . Remittance enclosed ADDRESS:... ......... Postcode .. 64 COMPUTER & VIDEO GAMES "


"ULTIMATE ULTIMAX american NOW WATCH THIS SPACE . ALL AT YOUR FINGERTIPS In Las Vegas everybody's talking General Consumer Electronics about the Ultimax, Commodore's have looked around for some new games machine. This novel games to bring to the mar$149.95 system has a higher ket. They have succeeded with a specification than the VIC-20, new range of wrist watch size which is twice the price. We can games. expect it in Europe in the sumArcade Time has Hyperblast, mer with a price tag of around Planet Raiders, Galaxy Gunner and Cosmic Clash; Game Time The Ultimax is a programmable Touch & Tell has Firing Squad, Missile Strike, Alien Assault and Blast Away: colour computer which connects directly to the TV. It has a memwhilst Sports Time has Football, brain keyboard, like the ZX81, and Basketball and Soccer. They also tell the time! can be programmed in Basic. It uses both plug in cartridges The animated LED displays not VIC 20 compatible and occupy an area of just 1\" x 1\". cassettes, and uses some of the Casio introduced a whole range VIC 20 peripherals like joyof calculators that sing, tell forsticks, paddles and light pens. It tunes, play games, tell the time does not have any expansion ... and even calculate! They parts, and is not planned to take included a calculator that sounds any communication, disc or like ten different instruments; a printer peripherals. calculator that is really a miniaIt has a polyphonic sound ture player piano that can store generator, and an overlay up to 240 notes and then play keyboard turns it into an elecThe Texas Touch and Tell is a out for the educational game them back automatically; one tronic organ similar to Casio's game based on the original market. that has three different games, early VL-Tones. Speak and Spell. This one is A new cheaper Speak and and one that simulates a boxing Commodore have signed an aimed at younger children, and Spell -the Compact -has just ring. agreement with Bally to transfer instead of a keyboard, a series of been introduced and costs only The MG777 has three built in some of their arcade games to overlays present pictures, let$45. games in addition to the usual VIC 20 and Ulitmax cartridges. ters, numbers and shapes. Texas Instruments have also calculating facilities. The games Ultimax has a resolution at least The machine then asks the introduced 26 new software include Digicube, Digislot and twice that of the VIC 20, with a 40 player to touch the appropriate packages for the 99/4 computer. Trackdown. Digicube is quite difcolumn by 25 row character drawing and responds accordThese include: T.I. Invaders; Car ficult, and involves getting all screen. ingly. With the success of the Wars; Adventure; Munch Man; nine squares filled up with a The VIC 20 has some exciting Speak and Spell, and its other Speak and Spell and Speak and preset number, in a preset new programs, including VIC systems like the Little Professor, Math; lots of educational softnumber of moves. Avenger, a copy of the original Texas Instruments is going all ware; and business aids. Each press of a key adds one arcade game, Slots which is a to the randomly arranged severy realistic slot machine, quence. Digislot is a slot machine Poker, Jupiter Lander, Super tle caveman past a ravenous game and Trackdown involves Alien, Midnight Drive and Magic dinosaur which is between you Mouse. and the cave. Just to make life An 8K memory expander and a interesting you also have to dodge random lightning bolts. cheap modem ($109) have also been released for the VIC 20. It One company that made its King Kong involves saving a now has a big brother, the VIC 20 debut in 1981 was Tiger Eleclady held captive by, a giant gorilla on top of the Empire State 16 which has a 16K memory as tronic Toys. Their systems are standard. Also introduced is the just available in the UK. Building. In Space Flight you defend your space fleet from the Commodore 64, a 64K colourThey have introduced some invaders. computer that looks just like the hand held games which include a VIC 20, has a 40 column screen, built-in clock. The models have Monster Maze has joystick runs all VIC peripherals and all animated figures and the L.C.D. control and full colour animation Ultimax cartridges. This is priced displays use multi-coloured and involves avoiding a monster whilst getting to the centre. tabletop arcade game Super FootPictured is the U.S. Games Corp's at $595 say  when it graphics. They also have sound Finally, Dragon involves saving ball. This game is based on Amerieventually reaches the home effects. maidens from a tower while at can football. Caveman involves getting a litmarket. the same time avoiding a fire breathing dragon. following lighted squares on the Tiger also have a couple of keyboard. Model BG8 has a built commodore educational games based around in boxing ring when the game is COMPUTER their K-Z-8 talking learning comactivated two boxers appear in puter. These cartridges now the display area of the unit. consist of subjects such as geoIt is up to the user to knock graphy and grammar. They have out the contender by pressing also introduced a talking picture various keys on the calculator. As book which looks very similar to both fighters exchange punches, the Texas Instruments Teach and the unit automatically keeps Tell. score. "


"1 2 3 PINBALI machines you can simply bash See me, feel PINBALL me, touch me, the ball around the playfield IS BACK hear me! ... and not know why lights are demand the flashing or if you've collected loud, flashy bonus points. machines Players face a real challenge STYLE which have if they step up to one of Bally's quietly found latest pinball creations called their way back to their tradiCentaur. This sinister looking tional haunts in pubs and machine it is resplendent in horror show black and white arcades. Pinball is back — brighter and brasher than artwork is packed with skill ever. features. The video boom almost Unique to the machine is a wiped out this denizen of the feature called equitable multiamusement palaces but ball. What that means is that behind the scenes the pinball each player has to build up his makers were working out a own store of balls for multiball way to beat Space Invaders play, getting no advantage and video machines at their from the skills of a previous own games. player. Aided by the microprocesThe play centres around sor, a new generation of releasing captive balls. This is \"pins\" were born. And now achieved by hitting a configyou'll believe that pinball can uration of targets with talk! They challenge, encourO.R.B.S. lettering. age and even insult the player Hit in sequence these release using a wide vocabulary of a captive ball. Hit out of sequelectronic utterances. ence they store up a number of Between the Xenon possible captive multiballs in machines' sensuous tones that the machines memory to a them with video games. Now before. There's always going to maximum of four. to the Medusa's fierce \"Chal there's a shift back to pinball. be pinball.\" These can be release by lenge the Medusa!\" there are a One of the first machines shooting the right passageway variety of words and phrases Bally produced in their fight TAROSTO The TARHS The new when it is lit. the dedicated pinball player against the video games was neon-bright The Centaur also has one can wring from his favourite cheekily called Space InvaderTO TEST Pinball other disconcerting feature machine. and it produced sounds just machines have it plays itsell. When no-one has But how did pinball bounce like the video game of the same YOUR plenty of sur-approached its coin-slot for back? Computer and Video name. prises in store what it regards as an Games visited the Wembley \"Kids get to a certain level SKOTT for the uniniti unfriendly length of time it headquarters of Bally Conti on a video machine. Say they ated who step blasts out live balls and sends score 10,000 points every time up to sample their delights. them rocketing around its own on their favourite machine, Experienced players like to playfield just to get a bit of and they keep on scoring see ingenuity used in the design attention. 10.000 points. They get so good of the machines. Multiball feaIf this singular machine's that they become bored with it. Itures are a big favourite but hipper buttons are pressed \"With pinball, no two games tests of skill, in whatever form when the game is over it speaks are the same. They could score they appear on the playfield, out listing its skill features 10,000 one game and an are essential if a pinball is to anyone who will listen while embarrassingly low score the going to be a winner. colour coded lights flash in next time they play. They keep Players also like to get clear unison. coming back to play again to instructions on the machines Elektra is another Bally about target sequences or machine soon to be seen in the He adds that pinball debonus features and how they arcades. This has a novel three signers now concentrate on can get them. On some level playfield — with a minibuilding more features into machines to test the skills of the beat the mac Pictures by Linda Freeman players. Features like captive balls only released when targets are nental one of the big three hit in the correct sequence, pinball manufacturers and dis multi-level playfields and skill tributors. There we talked to shots which send the players' David Adams, managing direcscores soaring. '' tor of Bally's operation in this 1 There are machines which country. send several balls rocketing \"The video boom gave pin down the playfield at the ball a shot in the arm,\" Adams player during a game just to told us. «It encouraged the keep him on his toes. evolution of the machines. With the voice, revamped \"I've been in the business 20 sounds and lights and the skill years and it's incredible the features these new pinball way they have developed. The machines are in good shape to new games are tremendous give the video games tough quality-wise and player-wise. competition in the arcades, \"Three years back, arcade managers were taking out their \"Pinball is always going to pinball machines and replacing have knocks. It's seen it all 66 COMPUTER & VIDEO GAMES "


"SCREEN TOPPERS a fourth, Stern field at its heart. This can only PLAYING Microcompu-play and, depending on the be reached by collecting ters have taken version of pinball, the player is Elektra \"time-units\" on the ON THE pinball out of given a different number of upper levels. the arcade and balls with which to bump up It has two captive balls on SMALL given it ahis score. the top and second levels screen image. Pinball is also available on which are released after targets Now that television games centres, are hit in the correct sequence. colour has although they are not the most Once on the mini-field players become an integral part of so popular of the range. Philips can earn up to 195 thousand many home computers, the has a version for the G7000, points on its bonus features. game can be brought to life in ACE does a pinball game for Multiple flippers feature on your own living room. It can the Acetronic MPU 1000, and Bally's Medusa game which I like the Motorola 6800 which like the Motorola 6800 which still be an exhilarating game Voltmace produces one for the has a two-level playfield. It also masterminds absolutely every-1 although the action bears little Database games centre. has a useful shield post located thing. resemblance to the feel of a DATED The T.I. 99/4a between the lower flippers One of the most successful buzzing machine beneath your RASIERT computer also which — if you've built up companies, Bally, claims it will outstretched fingers. enough bonus points enables be changing this microproces Computers do have certain BLASTER has a pinball cartridge simiyou to save a doomed ball with sor soon in order to cut down advantages, however and Tandy has brought out an DOWN a touch of a button. It also on the number of matrix lar to the Tandy aughs at you when you lose a boards inside the machines. version giving a exciting innovation for SI TAT TO ZERO custom-designed A ball which can be very Artwork is now a big feature TRS-80 Colour Computer vergame. This is irritating! called Zero Zap. You have to set up your own field positionTHE BIG The big three ing on it diamonds and crosses pinball makers to increase your chances of THREE are all American — Bally, scoring points. This game difTABLE Gottlieb and fers from the original arcade Williams, with game because you have to aim an arrow which you control at 00 a target, either diamonds or taking some of crosses, and fire. When you the market. There is also a score a direct hit the diamonds Spanish manufacturer but change into crosses, and vice their products are specifically versa. for that country. One of the best standard The biggest market for pinballs is of course in the computerised pinball games is an American one on sale in the USA. Germany and France are UK. It has the memorable also pinball provinces as is name Raster Blaster and is Italy. In comparison, Britain is available through Apple softstill a small market for the ware dealers including Zynar machine makers. and SBD Software of RichBally based in Chicago mond. Pat Salt of Zynar said: has a large design team work\"It's really pretty good. Of the ing on new themes and designs pinball machines I have played for its products. I think Raster Blaster is as Prototype designs are tested good if not better than some in on site before the pinball factories swing into production of arcades.\" «The flippers in arcade a new model. One of the new microprocessor models would games haven't always worked when you want them to, or as cost the buyer around ,000 but second-hand models can quickly. With Raster Blaster be picked up for around . they are very prompt and easy Older, electro-mechanical of the pinball with elaborate sion of the game. to control and handle.\" models can be found for less. designs decorating the back-1 This cartridge will allow the Other computers are wellsplash the artwork on the player to design his own table. catered for on the pinball UNIT ! In its late 50s machine's scoreboard and He decides how many flip-front, as well. Cassettes rangI heyday, pinball playfield. pers in each game, where they ing in price from .50 up to PINBALL was a really Bally produced a machine should be positioned and the top-of-the-range discs with simple machine called Lost World with an degree of difficulty involved in sophisticated sounds and PAMELO with a few Adventure/Fantasy theme the game. graphics in the  range, are pot-bumpers and received orders for the In the past computerised proving popular with software and couple of backsplash alone for people to pinball games have fallen short buyers, as the home market nippers, comhang on their walls. Some were of the arcade machines but this follows the arcade trend. pleted by one-dimensional art stolen from exhibition stands. now seems to be changing. work on the playfield and What will the future offer? Computerised pinball is repbacksplash. Yet more mind-boggling play. resented on the screen in sev Inside it was full of electro fields and tests of the players' eral ways. As a table layout, mechanical levers and switches skill. One of the newest complete with mushroom a real plumber's nightmare. machines, yet to be seen in shaped bumpers with the difThese machines are now collec-arcades, is the vector. ferent scores marked on them, tors' items and Bally often get This has a shooter lane gates which open and close at requests for parts and spares which fires the ball out at an random intervals and bats for vintage machines from pin angle onto the lower playfield which represent the pinball ball enthusiasts. if you are lucky or skilful table's flippers. Nowadays pinballs are conenough it whips up a chute to Most of the games have trolled by a microprocessor the top level. sound effects which enhancel 00 AGE ledus "


"MACRONICSZX80 and ZX81 ZX81 another ZX80 ARCADE GAMES FROM QUICKSILVA IK Space Invaders ALL PROGRAMS WRITTEN IN MACHINE CODE TO ENSURE FAST FLICKER-FREE GRAPHICS 26 Spiers Close Knowle, Solihull West Midlands B93 9ES England A superb version of the famous arcade game in fast interactive graphs. A4 x2 array of aliens descend moving right & left and they can detect your Laser Base so keep it on the move. Previous and current game On screen scoring. Destructable protective shields and keyboard control of the Laser Base & Laser Bolt firing using (& and the Rubout key. QS DEFENDER Generally considered to be the best arcade type game available for the ZX-Computers IK Breakout QS ASTEROIDS An interactive graphs 9 ball game, as Invaders written in mic for good graphs Try your skill and patience at knocking all bricks from the wall.Use & to control the paddle. First and only full screen display Software to drive OS sound board Moving planet ary surface Up to 84 fast moving charac ters on screen at once. On screen scoring Ten missiles at once increasing attack patterns as the game progresses Quicksilvas new arcade game Left-Right Thrust Fire Software to drive OS sound board. Multiple missiles firing in 8 directions On screen scoring increasing number of asteroids Full mobility of ship to all areas of the display Asteroids break up into smaller asteroids when hit Wrap around screen. IK Music From a range of 8 notes you can use your ZXos a toy piono Your selected notes are written to cassette-continous prompt for new selection of notes-play back your cassette and just listen to it sing. Example tunes. 3 CASSETTES & PROGRAM LISTINGS FOR ONLY .95!! Startrek 16K All the usual features .95 Life 16K — Fast full screen M/C version .95 Mission of 16K A dangerous recovery mission The Deep in the murky depths. 3 play levels. .95 Pontoon/Fruit Machine 16K Good graphics .95 16K Ram Pack (ZX81) .50 All programs are recorded twice on high quality cassettes to ensure reliability, Cassette inserts are full colour reproductions of original artworks by \"STEINAR LUND. Full instructions sent with order STOP PRESSOS Invaders 7K-STOP PRESS AS-DEFENDER SK For ALL machines with BK ROM and minimum of 3K of RAM QS ASTEROIDS For ZX-81 (or ZX-80 with 8K ROM and FAST/SLOW mod) 4K RAM All at the fully inclusive price of .50 each For complete arcade realism Quicksilva also produce a range of high quality hardware. QS SOUND BD For 3 channel sound effects or tunes AS CHRS BD Program your own characters for use with any program. Enables display of real SPACE INVADERS characters on your machine Also OS MOTHER BD and QS 3K RAM BD Send S.A.E. for data sheets on our complete range of products. Orders and enquiries should be sent to the following address: QUICKSILVA, 95 UPPER BROWNHILL ROAD, MAYBUSH, SOUTHAMPTON, HANTS PLAY FOR TODAY COMMODORE VIC VIDEO GENIE I Machine Language monitor Sound and Lower Case Renumber and Screen Print .00 TRS80 MODEL Colour Sound Programmable Function Keys SK Memory Expandable to 32K Standard PETBASICI Full sized Typewriter Keyboard Graphics Character Set Plug-in Program Cartridges Low Priced Peripherals Self Teaching Materials E189.95 VIC Compatible Cassette .95 TEAC DISK DRIVES Interfaces with Video Genie, North Star Horizon SIEW W W 71 . 10 Track Single 1 0 Track Double .00 Disk Drive * .00 O Track Single O Track Double Disk Drive .00 Disk Drive 599.00 ACORN ATOM 48 K User Ram Extended Microsoft Basic Parallel or RS232 Interfaces With 10 Track Single Density Disk Drives .00 With 80 Track Double Sided Disk Drives .00 With 80 Track Double .00 SHARP MZ8OK 48K User RAM Extended Basic Integral .00 NEW THE COMPUTERSHACK .8K Rom + 4K Ram Sound  20 Introductory Programs 0000  Built-in Colour .00 Computer Shack Ltd. 14. Pittville Street Cheltenham Glos. Telephone:(0242)584343 Credit available through major credit company. Access or Barclay Card Accepted, Mailorder Enquiries Welcomed. Prices include VAT 68 COMPUTER & VIDEO GAMES "


"ZX81 HEWSON CONSULTANTS ZX81 00000000000000000009 FOOTBALL? MANAGER 4. HINTS & TIPS For the ZX81 by Andrew Hewson E4.25 \"Good value and quite fascinating... a very inexpensive way of acquiring months of programming experience\" YOUR COMPUTER Nov 81 \"Excellent... very good value for money\" SYNC Saving Space... Understanding the Display File... Converting ZX80 Programs... Chaining Programs pass data between programs, call subroutines from cassette, establish data files Machine Code Programs write, load, edit, save and debug machine codel. Routines and programs are scattered liberally throughout the text and the final chapter consists of twelve useful interesting and entertaining programs 16k RAM PACK .50 A top quality add-on 16K dynamic memory specially designed for the ZX81. Simply plugs into the port at the back of your Sinclair. Can be used in conjunction with the ZX printer. Neatly packaged in a black plastic shell to match your ZX81 Incredible value, why pay more? A GREAT A NEW GAME from Addictive Games 000000000000000000000 ZBO OP CODES .45 A must for the beginner and the experienced programmer alike. This handy ready reckoner lists all 600 plus 280 machine code instructions in decimal and hexadecimal with the mnemonics. Each Op Code is succinctly explained and Cross-referenced Supplied in a protective transparent wallet for easy reference and durability, PROGRAMMERS TOOLKIT (4k) .50 Are you writing your own programs for the ZX817 Then use our TOOLKIT to do the donkey work. Copy it into RAM before you start work then you will have it at your fingertips. Comprehensive LINE RENUMBER including GOTOs and GOSUBS; LOAD, EDIT and RUN machine code programs; INSPECT the ZX81 system routines; COPY them into RAM and PATCH and or EXTEND them: FIND a given piece of Basic code and REPLACE all occurrences of it move blocks of Basic lines with EDIT for ZX81, ZX80, TRS80, VIDEO GENIE JUST LOOK AT THESE FEATURES 4 Divisions Promotion & Relegation *FA Cup Full League Tables Transfer Market (Buy and Sell Players) Pick your Team for each Match (but watch out for injuries!) * As many Seasons as you like *7 levels of Play (from Beginner to Genius!) * Managerial Rating (tells you how good you REALLY are!) Save Game Facility (continue again another time) All this and much much more packed tightly into 16K RAM 0000000000000000000000000000000 \"IF YOU LIKE FOOTBALL YOU'LL LOVE THIS GAME' STATISTICS (1) .75 Three programs on the one cassette 1) i) Statistics prints the current mean and standard deviation after each value is entered il Regression prints the current mean and standard deviation of the y andx values and the intercept and slope of the regression line Trend prints the current mean and standard deviation of the y and x values and the intercept and slope of the trend lines 21 CHI SQUARED TEST prints the current value of the Chi squared statistic and the current sample size 3) GRAPH PLOT plots a graph of data entered from the keyboard To Order send Chequel P. for 9.95 made payable to ADDICTIVE GAMES 2 HARDWARE REQUIRED:ZX81/ TRS80/ ZX80 Video Genie 8K ROM LEVEL 11 16K RAM 16K RAM Cheque with order or quote Access or Barclaycard number to: HEWSON CONSULTANTS (C.V.G.). 7 Grahame Close, Blewbury, Didcot, Oxon OX 11 9QE. Tel: (0235) 850075 P0. Box 28 CONNIBURROW MILTON KEYNES MK 14 NE PLEASE STATE COMPUTER OOOOOO0000000000000 AVALON HILL MICROCOMPUTER GAMES No less than 10 thrilling, action packed games on cassette, suitable for use with Pet, TRS 80 and Apple computers. And our latest titles include programs for the Atari. COMPUTING TANKTICS TANKTICS A unique game which uses a board and counters as well. The computer moderates combat and movement and keeps records letting you plan your strategy in this classic tank vs tank battle. .95 + .60 p&p Also available in this series: . MIDWAY CAMPAIGN .95 + PLANET MINERS .95  B-1 NUCLEAR 11 LORD OF KARMA .95 BOMBER .95 # EMPIRE OF THE  NORTH ATLANTIC OVERMIND .95 CONVOY RAIDER .95 . CONFLICT 2500 .95  NUKEWAR .95 ACQUIRE .95  16k all machines + 16k TRS 80, Apple, PET: 24k Atari 1t 48k TRS 80: 32k Apple, PET: ** 16k TRS 80, Apple, PET: 32k Atari 40k Atari # 48% TRS 80, Apple: 40k Atari: All games on cassette only not available for PET When ordering by mail, please add .60 postage & packing per game. Please send cheque/PO's to: AVALON HILL GAMES, 650 High Road, North Finchley, London N12 ONL, Dept CVG4182 LOOK OUT FOR MORE NEW MICROCOMPUTER GAMES IN 1982. Trade enquiries welcome. MOVING AHEAD WITH ZX SOSTWARE ZX CHESS I reduced to .50 Very popular machine code program, with six levels of play and an analysis option. Unbeaten except by ZX CHESS II now only .99 A new improved version, with a faster response time, seven levels of play, and in addition a recommended move option. ADVENTURES Exciting machine code games with instant response, choose from the range below ADVENTURE 'A' .00. You find yourself stranded on an alien planet. Can you reach your ship and escape? ADVENTURE 'B' .00. In a jungle clearing you come across an Inca temple. You must break in, collect treasure and escape alive, Beware. Includes a cassette save routine ADVENTURE 'C' E8.00. You are unfortunate enough to be drawn to an alien cruiser. Can you reach the control room and free yourself or will they get you first? Includes a cassette save routine GALAXY WARRIOR .00 Fast and exciting interactive animated graphics game. Hunt Clingons and go through black holes GALAXIANS .50 All the features of the arcade game in a fast machine code program, swooping attackers, explosions and personalised scoring 1K GAMES PACK .00 and many more. For a catalogue giving full details, please send a S.a.e. to: ARTIC COMPUTING 396 JAMES RECKITT AVENUE, HULL HUS OJA COMPUTER & VIDEO GAMES 69 "


"DOWN TO BASIC DOWN TU Dr.BY MOIRA NORRIE VARIABLE VALUES .. AVOIDING MISTAKES There are many occasions when it is desirable to perform a calculation in a program without immediately printing the result. It may be that the value produced is only an intermediate value in some calculation, or, the value is to be stored for use later in the program it would be wasteful to perform the calculation more than once. The LET statement is used to allocate a value to a variable. The general format of the LET statement is <line no. > LET <vari. able> = <arith. expr. > The operation of the LET statement can be described as follows: the arithmetic expression on the right of the \"=\" is evaluated; the resulting value is then assigned to the variable on the left of the \"=\". Assume that a program has three variables A, B and C. At some point in the execution of the program A has the value 2, B has the value 5 and C has the value 3.5. If the next statement is: 80 LET S = A + B + C then after this statement has been executed, the value of variable S will be 10.5 and the values of A, B and will be unchanged. If the computer now encounters: 90 LET A = A +1 then the following sequence of events occurs: the computer first looks up the current value of A and finds \"2\", this value will be copied into the part of the computer that performs arithmetic; it then adds on \"1\" to get the value \"3\" for the arithmetic expression. On examination of the variable name on the left of the \"\" it stores the value \"3\" for A thus 70 COMPUTER & VIDEO GAMES overwriting the old value of A with the new value. The statement: 90 LET A = A +1 therefore means, increment the value of A by 1. Last month, I gave an example of a program to count the number of words with four letters that were typed in. In that program, I used a statement similar to the one above to increment the count each time a four-letter word is input. Another common use of the LET statement to update the value of a variable, is the idea of maintaining a \"running total\" in a program. I will now look at an example of a program that uses this technique. A football team wants a program to calculate their average crowd attendance in a season of 40 games. The outline of the program would be: running total = 0 repeat 40 times input no. in crowd let running total = running total + no. in crowd end repeat let average = running total/40 print results In many versions of Basic, the first line is not essential since all variables are assigned the value \"0\" initially. When a variable is used as a count or a running total, a vital part of the logic of the program is that the variable should be initialised to \"0\" -it is a matter of convenience that most versions of Basic automatically perform the initialisation for us. Although the calculation of the average could be included in the Print statement, I shall put it in a separate LET statement so that the Print statement is less cumbersome. 10 REM CALCULATE AVERAGE 20 REM CROWD ATTENDANCE 30 FOR I = 1 TO 40 40 INPUT N 50 LET T = T +N 60 NEXT I 70 LET A = T/40 80 PRINT \"AVERAGE CROWD ATTENDANCE =\";A 90 END Even this simple program could be extended. One improvement would be the use of printing messages to tell the user what the format of the data typed in should be. Examples of this were introduced last month. Another improvement would be the inclusion of data checks. I am sure you are all well aware of how easy it is to make typing mistakes. A great problem in computing is the detection of such errors in the data. Some errors are very difficult to detect-for example, someone might type their age as \"22\" instead of \"33\" however, others are easier to detect for example, a person typing their age as \"322\" lies outside the possible range of values. Let's assume in my previous example that the maximum crowd that the ground could hold is 20,000. Then the value of N should lie in the range 0 to 20,000. The section inside the FOR loop could be extended to 40 INPUT N 44 IF NOTHEN 54 48 IF N>20000 THEN 54 I 50 LET T = T +N "


"52 GOTO 60 54 PRINT \"ERROR — PLEASE RETYPE\" 56 GOTO 40 COMMON USAGE A further check is that N should be an integer value. This can be done using the function INT INT(N) returns the integer part of N. If N has an integer value, then INT(N) will equal N. I can there. fore introduce one more statement in the loop: 42 IF N<>INT(N) THEN 54 For reasons of brevity, I am unable to include all these data checks in my sample programs. I have already used the functions INT and RND in the series. A number of commonly used functions are available in Basic as standard functions. This saves the programmer having to write his own programs (or parts of programs) to evaluate such functions. The standard functions provided will often depend upon the power of the version of Basic. In the table, I have listed the most common standard functions and briefly described their use. As many of them are mathematical, I can only suggest that you ignore those you don't understand! Wherever the function operates on a value enclosed in brackets after the function name -that value may be given as a constant, a variable or an expre. ssion. For example: INT(6 = RND+1) LEN(\"CAT\") Note that brackets are not required after the function name on the Sinclair ZX81. TABLE OF STANDARD FUNCTIONS Olli Function INT ABS SGN SQR LOG EXP SIN COS Description integer part absolute value the sign of a number square root natural logarithm exponential function sine (radians) cosine (radians) arctangent Example INT(3.2) = 3 ABS(-) = 2 SGN(-2) = -1 SQR(4) = 2 LOG(2) = 0.69315 EXP(1) = 2.71828 SIN(0.5) = 0.47943 COS(0.5) = 0.87758 ATN(1) = 0.78540 ATN LEN length of string LEN(\"CAT'') = 3 RND pseudorandom number between 0 and 1 RND = 0.217873 However, you should include them in any programs you write. Don't assume that someone running your program won't make mistakes or deliberately try to sabotage your program! The IF statement tests whether a specified condition is true. So far, the conditions have been simple in that they only involved one test. For example: NO or N<>INT(N) a specified range. In my example, I had an error condition if either N was less than 0 or N was greater than 200000. This required two IF statements lines 44 and 48 of my program. It is possible to combine these into one IF statement: NEXT ISSUE SYSTEMS SUMMARY 45 IF NOORN>20000 THEN 54 When moving to a new computer system, or converting programs from one system to another, it is useful to have a summary of the main features of the version of Basic used. In each future issue, I will provide a reference table for one particular system. The table will outline the main differences between standard Basic and the version used on that system. It is envisaged that most of the popular systems will be included. Next month, I will start by looking at the Sinclair ZX81. Thus, simple conditions can be combined using \"OR\" to form complex conditions. If any of the simple conditions are true, then the whole complex condition will be true and a jump will be made to the given statement. It is also possible to check that a number of conditions are all true by combining them with 'AND' in a single IF statement. 115 IF NS = \"SMITH\" AND A = 20 THEN 200 could be used to identify persons with the name SMITH and age COMPLEX CONDITIONS It is possible to have more complex conditions that involve a combination of simple conditions. This is particularly useful when testing that a value lies in NEXT ISSUE COMPUTER & VIDEO GAMES 71 "


"Adventure 100 REM start of main loop 150 LET OT$ = \"\" LET OW$ = \" LET OS$ = \"I CAN SEE.\" 160 FOR I = 0 TO 3: IF P (1) = IN THEN LET OW$(I = $(1) + TO SCROLL OR NOT SCROLL What is the best way to use the screen to display your adventure? Sooner or later in writing an adventure you must decide whether to use the conversational scrolling technique or a whole screen approach. The disadvantage of scrolling becomes obvious when the player has to recall details of his location, which can soon become tiresome. As soon as the machine reply is decided it may be screened with a PRINT statement, and the program looped back to the INPUT line. However, I prefer to clear the screen and redisplay the location details together with the machine's reply. In my opinion this gives a more polished appearance to the game, the player having more relevant information displayed at any one time. It is also useful to display the player's last command — if the computer's reply is a bit mystifying he can check what it was responding to, a typing error maybe? If the screen is cleared when INPUT is received, and PRINT statements executed as each piece of information to be displayed is available, the presentation will look very jerky, leaving the player in a state of nerves waiting for the whole thing to crash! This can be avoided if all the replies are assigned to variables and only when all are set is the screen cleared. All these variables can now be screened at once, providing a smooth change and giving the illusion of speed, since the screen is never really blank. Using Qi$ for the reply, the lines 3000 to 3050 described last month will look like: 3030 LET Q1$ = 'IMPOSSIBLE : GOTO 100 Between lines 100 and 150 we will insert some IF statements later. Using OT$ and OW$ for the objects, display coding will now look like this: 170 IF LENOS$) + LENOW$) < (no of characters per line on the screen) THEN LET OS$ = OS$+OW$ ELSE IF LEN(OTS) + LENOW$) <(no. of chars) THEN LET OT$ OT$ + OWS. 171 REM to prevent object lists wrapping round 180 (clear screen) :PRINT LS(LN): IF LENOS$) > 12 THEN PRINT OS$ : IF LENOWS) > 0 THEN PRINT OW$: IF LEN(OT$) > 0 THEN PRINT OT$ 190 PRINT \"YOU TOLD ME TO\", R1$: IF LEN(QI$) > 0 THEN PRINT QIS IF LEN(Q2$) > 0 THEN PRINT Q2$ 191 REM only print replies that exist 200 LET Q1$ \"*: LET Q2$ = \". : REM set replies to null for next time round 210 INPUT RI$: REM continue with next command ENTER THE HELLFIRE DUNGEON Many Adventures are trying to more faithfully recreate the fantasy roleplaying Dungeons & Dragons game which originally spawned the computerised version Hellfire Warrior is an example of the D&D Style very different from the plain language type of game but just as intriguing The version I played was supplied on cassette for TRS-80 (Model ! only, the game also being available for Pet, Video Genie and Apple machines, and on disc. The package is very impressive, and includes loading instructions for the particular machine, a command code prompt card, and a well produced and nicely illustrated booklet deseribing the background to the dungeons, monsters and treasures. After loading the first program on the tape. The Innkeeper you are given gold coins and assigned varying degrees of the attributes intelligence, intuition, strength, constitution, dexterity and ego. These all have a bearing on the outcome of future actions. You are now invited to bid for weaponry and armour which come in different shapes and sizes, and for slaves and elixirs. This turns into a real bartering session, with a very realistic simula tion you will need your wits about you to obtain what you need at the lowest possible price. If you offer an insultingly low price, the chances are you will get an equally insulting reply! When fully equipped you are asked which level of the dungeon you wish to enter. Data followed by a second program The Dungeon Master is automatically loaded, all previous data being preserved during this load. You are now in the dungeon, your immediate environs being displayed graphically alongside such details as: fatigue, wounds, room number. You must explore the dungeon, seeking out secret doors and traps, avaiding or killing monsters en-route whilst collecting treasures. This is where familiarity with the command codes is useful hang around too long and the Giant Red Ant or the Great Tick will get you! Should you be lucky enough to get your treasures back to the inn before Olias the Dwarf catches you, they can be exchanged for gold. You can then input your latest experience level and attributes back into the Innkeeper program, and start oft again towards another more difficult level. Altogether a very deep game, and cleverly written. It should please Dungeon & Dragons fans and Adventurers alike. Many thanks to Allgray for the review tape, and to Mark Jenkins for initiating me into D&D, before 1 tackled this game! By KETH CAMPBELL "


"132 OFTWARE EDUCATION 2 SUBTWAFIE FOLEDAD G Make the most of your Sinclair ZX Computer... Sinclair ZX software on cassette. .95 per cassette. OFTWARE 2X8I The unprecedented popularity of Cassette 1-Games the ZX Series of Sinclair Personal For ZX81 (and ZX80 with 8K Computers has generated a large BASIC ROM) volume of programs written by users. ORBIT-your space craft's Sinclair has undertaken to mission is to pick up a very valuable publish the most elegant of these cargo that's in orbit around a star. on pre-recorded cassettes. Each SNIPER you're surrounded program is carefully vetted for by 40 of the enemy. How quickly interest and quality, and then can you spot and shoot them when grouped with other programs to they appear? form a single-subject cassette. METEORS-your starship is Each cassette costs .95 cruising through space when you (including VAT and p&p) and comes (including VAT and pocp) and comes meet a meteor storm. How long can wions can complete with full instructions. you dodge the deadly danger? Although primarily designed LIFE-J.H. Conway's Game of for the Sinclair ZX81, many of the Life' has achieved tremendous cassettes are suitable for running popularity in the computing world. on a Sinclair ZX80-if fitted with a Study the life, death and evolution replacement 8K BASIC ROM. patterns of cells. Some of the more elaborate WOLFPACK-your naval programs can be run only on a destroyer is on a submarine hunt. Sinclair ZX Personal Computer The depth charges are armed, but augmented by a 16K-byte add-on must be fired with precision. RAM pack. GOLF-what's your handicap? This RAM pack and the It's a tricky course but you control replacement ROM are described the strength of your shots. below. And the description of each cassette makes it clear what Cassette 2-Junior hardware is required. Education: 7-11-year-olds 8K BASIC ROM For ZX81 with 16K RAM pack The 8K BASIC ROM used in the CRASH-simple addition-with ZX81 is available to ZX80 owners the added attraction of a car crash as a drop-in replacement chip. if you get it wrong. MULTIPLY-long multiWith the exception of animated graphics, all the advanced features plication with five levels of of the ZX81 are now available on a difficulty. If the answer's wrongthe solution is explained. ZX80-including the ability to run much of the Sinclair ZX Software. TRAIN-multiplication tests against the computer. The winner's The ROM chip comes with a new keyboard template, which can train reaches the station first. be overlaid on the existing FRACTIONS fractions keyboard in minutes, and a new explained at three levels of difficulty. A ten-question test operating manual. completes the program. 16K-BYTE RAM pack ADDSUB-addition and The 16K-byte RAM pack provides subtraction with three levels of 16-times more memory in one difficulty. Again, wrong answers complete module. Compatible with are followed by an explanation. the ZX81 and the ZX80, it can beused DIVISION with five levels of for program storage or as a database. difficulty. Mistakes are explained The RAM pack simply plugs graphically, and a running score is rt on displayed. into the existing expansion port on displayed. the rear of a Sinclair ZX Personal SPELLING-up to 500 words Computer. over five levels of difficulty. You can even change the words yourself. Cassette 3-Business and Household For ZX81 (and ZX80 with 8K BASIC ROM) with 16K RAM pack TELEPHONE-set up your own computerised telephone directory and address book. Changes, additions and deletions of up to 50 entries are easy. NOTE PAD-a powerful, easyto-run system for storing and retrieving everyday information. Cassette 5 Junior Use it as a diary, a catalogue, a Education: 9-11-year-olds reminder system, or a directory. For ZX81 (and ZX80 with 8K BANK ACCOUNT-a BASIC ROM) sophisticated financial recording MATHS-tests arithmetic with system with comprehensive documentation. Use it at home to three levels of difficulty, and gives keep track of where the money your score out of 10 BALANCE-tests understanding goes, and at work for expenses, of levers/fulcrum theory with a departmental budgets, etc. series of graphic examples. Cassette 4-Games VOLUMES -\"yes' or 'no' For ZX81 (and ZX80 with 8K answers from the computer to a BAS BASIC ROM) and 16K RAM pack series of cube volume calculations. LUNAR LANDING-bring the AVERAGES-what's the average lunar module down from orbit to a height of your class? The average soft landing. You control attitude shoe size of your family? The average and orbital direction but watch the pocket money of your friends? The fuel gauge! The screen displays your computer plots a bar chart, and flight status-digitally and graphically distinguishes MEAN from MEDIAN TWENTYNE-a dice version BASES-convert from decimal of Blackjack. (base 10) to other bases of your COMBAT you're on a suicide choice in the range 2 to 9. space mission. You have only 12 TEMP-Volumes, temperatures missiles but the aliens have -and their combinations. unlimited strength. Can you take How to order 12 of them with you? SUBSTRIKE-on patrol, your Simply use the order form below, frigate detects a pack of 10 enemy and either enclose a cheque or give subs. Can you depth-charge them us the number of your Access, Barclaycard or Trustcard account. before they torpedo you? CODEBREAKER-the Please allow 28 days for delivery. computer thinks of a 4-digit number 14-day money-back option. which you have to guess in up to 10 tries. The logical approach is best! MAYDAY -in answer to a distress SNDEN ZX SOFTWARE call, you've narrowed down the search area to 343 cubic kilometers of deep space. Can you find the astronaut before his life-support system fails in 10 hours time? Sinclair Research Ltd, 6 Kings Parade, Cambridge, Cambs., CB21SN. Tel: 0276 66104. Please print Total To: Sinclair Research, FREEPOST 7, Cambridge, CB21YY Please send me the items I have indicated below. Qty Code Item Cassette 1-Games Cassette 2 Junior Education Cassette 3-Business and Household Cassette 4-Games Cassette 5 Junior Education *8K BASIC ROM for ZX80 *16K RAM pack for ZX81 and ZX80 *Post and packing (if applicable) Item price .95 3.95 .95 (3.95 3.95 .95 149.95 .95 Total *Please add .95 to total order value only if ordering ROM and/or RAM I enclose a cheque/PO to Sinclair Research Ltd for Please charge my Access/Barclaycard/Trustcard no. * Please delete as applicable Name: Mr/Mrs/Miss LLLLLLLLLLLLLL COMPUTER & VIDEO GAMES 73 "


"Sinclair ZX81 Personal Compu the heart of a system that grows with you. D .  95 SDFGHE VBNM Built: 1980 saw a genuine breakthrough the Sinclair ZX80, world's first complete personal computer for under . Not surprisingly, over 50,000 were sold. In March 1981, the Sinclair lead increased dramatically. For just .95 the Sinclair ZX81 offers even more advanced facilities at an even lower price. Initially, even we were surprised by the demand over Higher specification, lower price 50,000 in the first 3 months! how's it done? Today, the Sinclair ZX81 is the Quite simply, by design. The ZX80 heart of a computer system. You can reduced the chips in a working add 16-times more memory with the computer from 40 or so, to 21. The ZX RAM pack. The ZX Printer offers ZX81 reduces the 21 to 4! an unbeatable combination of The secret lies in a totally new performance and price. And the ZX master chip. Designed by Sinclair Software library is growing every day. and custom-built in Britain, this Lower price: higher capability unique chip replaces 18 chips from With the ZX81, it's still very simple to the ZX80! teach yourself computing, but the New, improved specification ZX81 packs even greater working Z80A micro-processor new capability than the ZX80. faster version of the famous Z80 It uses the same micro-processor, chip, widely recognised as the best but incorporates a new, more power ever made. ful 8K BASIC ROM the trained Unique 'one-touch' key word Kit or built-it's up to you! intelligence of the computer. This entry: the ZX81 eliminates a great You'll be surprised how easy the chip works in decimals, handles logs deal of tiresome typing. Key words ZX81 kit is to build: just four chips to and trig, allows you to plot graphs, (RUN. LIST. PRINT, etc.) have their assemble (plus, of course the other and builds up animated displays. own single-key entry. discrete components) a few hours And the ZX81 incorporates other  Unique syntax-check and report work with a fine-tipped soldering iron. operation refinements the facility codes identify programming errors And you may already have a suitable to load and save named programs immediately. mains adaptor 600 mA at 9V DC on cassette, for example, and to Full range of mathematical and nominal unregulated (supplied with drive the new ZX Printer. scientific functions accurate to eight built version). decimal places. Kit and built versions come com Graph-drawing and animated plete with all leads to connect to display facilities. your TV (colour or black and white)  Multi-dimensional string and and cassette recorder. numerical arrays. Up to 26 FOR/NEXT loops. Randomise function useful for games as well as serious applications.  Cassette LOAD and SAVE with named programs. 1K-byte RAM expandable to 16K bytes with Sinclair RAM pack. Able to drive the new Sinclair printer. Advanced 4-chip design: microNew BASIC manual processor, ROM, RAM, plus master Every ZX81 comes with a comprehensive, specially written chip unique, custom-built chip manual a complete course in BASIC programming, from first principles to complex programs. replacing 18 ZX80 chips. "


"puter PORE 9905 POKE 9986 LET 9987 RETU 9988 REM 40 PRINT AT 10,0;\"---ESN. F BURI) 2981 FOR a on 2000 Available nowthe ZX Printer for only .95 Designed exclusively for use with the ZX81 (and ZX80 with 8K BASIC ROM), the printer offers full alphanumerics and highly sophisticated graphics. A special feature is COPY, which prints out exactly what is on the whole TV screen without the need for further intructions. At last you can have a hard copy of your program listings -particularly useful when writing or editing programs. And of course you can print out your results for permanent records or sending to a friend. Printing speed is 50 characters per second, with 32 characters per line and 9 lines per vertical inch. The ZX Printer connects to the rear of your computer using a stackable connector so you can plug in a RAM pack as well. A roll of paper (65 ft long x 4 in wide) is supplied, along with full instructions. 16K-byte RAM pack for massive add-on memory. How to order your ZX81 by cheque, postal order, Access, BY PHONE Access, Barclaycard or Barclaycard or Trustcard. Trustcard holders can call EITHER WAY please allow up to 01-200 0200 for personal attention 28 days for delivery. And there's a 24 hours a day, every day. 14-day money-back option. We want BY FREEPOST-use the no-stampyou to be satisfied beyond doubt needed coupon below. You can pay and we have no doubt that you will be To: Sinclair Research, FREEPOST, Camberley, Surrey, GU15 3BR Qty Item Order Total Code Item price Designed as a complete module to fit your Sinclair ZX80 or ZX81, the RAM pack simply plugs into the existing expansion port at the rear of the computer to multiply your data/program storage by 16! Use it for long and complex programs or as a personal database. Yet it costs as little as half the price of competitive additional memory. With the RAM pack, you can also run some of the more sophisticated ZX Software the Business & Household management systems for example. 12 49.95 Sinclair ZX81 Personal Computer kit(s). Price includes ZXB1 BASIC manual, excludes mains adaptor. Ready-assembled Sinclair ZX81 Personal Computer(s). Price includes ZX81 BASIC manual and mains adaptor Mains Adaptor(s) (600 mA at 9V DC nominal unregulated) 16K-BYTE RAM pack. Sinclair ZX Printer 8K BASIC ROM to fit ZXBO. Post and Packing. 69.95 8.95 49.95 49.95 19.95 27 2.95 Please tick if you require a VAT receipt TOTAL  *I enclose a cheque/postal order payable to Sinclair Research Ltd, for  *Please charge to my Access/Barclaycard/Trustcard account no. *Please delete/complete as applicable. se delete/complete as applicable. LLLLLLL L L Please print Sinclair ZX81 Name: Mr/Mrs/Miss LLLL LLLLL Address: LLLLLLLLLLLLLLLLLL LLLLLLLL LLLLLLLLLLLLLLLLLL 6 Kings Parade, Cambridge, Cambs., CB2 1SN. FREEPOST -no stamp needed. CVO 04 Tel: (0276) 66104 & 21282. "


"E SOFTWARE SOFTWARE SOFTWARE SOFTWARE SOF REVIEWS REV ROMAN AROUND IN ANCIENT \"BRIGHTON\" England has always been a difficult country to conquer but Julius Caesar was one of the few foreign leaders to do so. During his governorship of Gaul he invaded Britain with 600 transports carry ing an army of five legions and over 1,000 cavalry. Sharpsoft of London has brought out a game which makes the player reenact the strategy he employed to wage war against Britain. If Sharpsoft had spelt the name of the game correctly it would have added more credence to the \"Caesar's Invasion of Britain\", which ultimately turned out to be worth sticking with \"Caesar's Invasion of Brighton\" the didn't aim high to start with) is an adventure game in which your job is to capture the stronghold of Cassivellaunus, a Celtic leader, and return safely to your ships. At the beginning of the game you are given the option of a CAESAR'S INVASION OF BRITAIN recruiting additional cohorts and cavalry you also have to deal with Roman elecand, more importantly, to hire scouts. tions, sending agents armed with money to Scouts are vital to your operation swing power your way. because without them there is no way of The game was repetitive when I played discovering the lay of the land, and the it. I seemed to wander around the counenemy's whereabouts. That's where tryside being attacked by various barmade my first mistake. barians, losing all my denarii and finally You also have a money, denarii, in your losing the vital battle. purse which comes in handy for bribing It costs .85 from Sharpsoft and runs on potentially harmful tribes. a 48K Sharp Food is also a vital necessity, without grain your troops will eventually starve unless you succeed in finding or stealing some bags. While battling out the invasion in Britain A MISSION TO WARP battle. After that I won about YOUR MIND THRESHOLD SOLAR STRATEGY keyboard, and accuracy in aiming is most important. It took me about 10 plays before I could hope to win a battle. After that I won about IRESHOLD 70% of the time, but I have not yet conquered the whole solar If Galaxians and Space Invaders are bat like creatures. These are system. caused you headaches, followed by Galaxian types which The display is nice, showing Threshold will give you migraine. plummet in a kamikaze style dive each planet in a distinctive way. It is one of the most compultowards your ship. and the scale has been well sive games I have come across the third type of alien looks GALACTIC ATTACK chosen to allow you to get lost, since green meanies and winged more like a member of the fish but not too often. Another nice creatures first flew onto my family and swims across the This battle for control of a solar feature is the ability to specify screen. screen above your ship. system relies on more than just various parameters such as Each time you successfully Your five ships are lined up on reactions and a fast finger on the number of Kzinti ships in each destroy one wave of invaders, a the right hand side of the screen, fire button. attack, speed and effectiveness different breed of creature and when play begins the The object of this dull but very of Torps, and other vital items. attacks. engines start to rev up. addictive game is to colonize a Beaming armies up and down You get five ships fully equip. Sheer compulsion apart, the solar system or free it from the between ship and planet is an ped with Delta class lasers to game boasts imaginative Kzintis-depending on your point added complication which I blast the aliens, but you must graphics and sound effects. of view. It is a difficult game to enjoyed but it is tedious in the take care not to run out of fuel by Because of the proliferation of master and requires strategic early stages. firing too many missiles. aliens, points are quite easy to thinking as well as tactical manRecommended to all commit. Also at your disposal is a hyper score and you also get bonus oeuvres and rapid reflexes. ted space war enthusiasts with warp drive which slows down ships after notching up 50,000 Control of your ship is via the time to spare! the alien action for a few sec. points, 100,000 points. keyboard, and requires quick Galactic Attack runs on a 48K onds. But because of the power Well worth spending the thinking when under attack from Apple under DOS 3.3 or Pascal, consumed during its use you can .95 on Threshold for your Kzinti ships. You also control costs .55 and is available from only activate it once. Apple || (48K). Richmond based your Torps and Phasers from the Woodland Software. The first onslaught of aliens S.B.D. Software is the supplier. "


"FTWARE SOFTWARE SOFTWARE SOFTWARE SOFTW TITTITTITUTI TAKE A SPIN DOWN THE ALLEY TENPIN SPADE AND SHOVEL WORK THE ALLEY . UNT we arrow keys and even space AMAZING JOURNEY the world, and le soin can be surven THROUGH PREHISTORY the aliens, but it varies and min, ALIEN Tenpin bowling must be one of A monster infested maze is the the last sports which would playground for a defensive seem suitable for computerisadeathgame. tion. The only way to survive in It says a lot for computer Alien is to dig holes at strategic games designers that they have spots in the labyrinth. When one come up with a version which of the killer red aliens falls into recreates the need for a good your trap, you can finish him off eye and judgement, and still by quickly filling it in. manages to be entertaining. Using the keyboard controls The screen shows the tenpin this game is awkward to play lane from the viewpoint of the joysticks are better. The keys to bowler, with the machinery, and operate your man are bunched the 10 pins that are to be backup copy together and to move him up, knocked over in the distance. ware, so should Tenpin is available from down, left or right needs some The rules of tenpin bowling a copy be spoiled, a new one Molimerx for the Tandy TRS-80, getting used to are simple, but for those not would be provided, but it would Models I and III and Video Genie, It's impossible to get around familiar with them, adequate have been nice to have the facil models I and II. The tape version this by using two fingers from instructions are included with ity (such as there is on the origicosts .93 and the disc version, each hand to manoeuvre the man the program. nal adventure game) to make one .95. about because you must work A ball is rolled down an alley the 'A' and 'D' keys to activate with the aid of the computer's the digging action with your left two arrow keys and the space hand. bar. Markings, a third of the way Points are scored by killing off down the alley, assist in aiming the aliens, but it varies randomly, the ball, and a spin can be given sometimes it could be 200, someto the ball any time up to it times 300 reaching these markings. A game Wandering around the fairground on MONOTCD MADE 3D MONSTER MAZE Alien requires concentration consists of 10 frames per person, sideshows, I heard a busker to work out the best places to you are allowed up to two balls enticing the crowd to roll-up and nosaurus Rex look suitably frighdig your holes without hemming per frame to knock down the 10 see the prehistoric monster tening as it paces toward you. you in you could be devoured by pins. The computer keeps your paid up and entered the tent. The maze corridors are cona monster). Don't dig holes which score, and displays this, together only to be enveloped in a grey stantly changing as you press the are too far apart. If you have a with any \"strikes\" or \"spares\" mist which transported me back 5, 7 or 8 keys to walk forward or long way to move your man into (knocking over all 10 pins with into the era of that mightiest of turn the corners. There is a way position by the time you reach one or two balls respectively) at beasts, Tyrannosaurus Rex. out of the maze but I have only the hole containing the founderthe end of the lane, to the left of Exploring tentatively, I stopmanaged to find it twice. If you ing monster it will be too late. He the pins. To the right of the pins ped at an intersection and looked do manage to exit then your only remains vulnerable for a few is shown a plan view of the pins around me. Then came the sound score is increased accordingly. It seconds. remaining standing of approaching footsteps. I ran, would be nice to have a high Not one of the most graphiAt the end of the game the turning this way and that but score facility included in the cally exciting of games for the scores for each player is shown there, looming above me, was program, though. VIC-20 from Commodore but will and you have the option of taking the dreaded monster. The huge The play can be speeded up or keep you busy for a while. Price part in another game. jaws opened to reveal his great slowed down if you alter the .95 from VIC software dealers. There can be between 1 and 4 teeth. I could just make out listing slightly. Instructions on players and the game has the something inside, I started to how to do this are included in the added effect of sound available read: \"You have been posthumnotes supplied with the cassette. through an amplifier. ously awarded 130 points and I have found myself wandering As usual the Tandy graphics sentenced to roam the maze around the maze with the monsare a limiting factor with this forever. If you wish to appeal, ter lying in wait, somewhere and simulation, though not as seripress 'stop' else press \"cont.\" I not wanting to come out. It does ously in this game as in others, pressed cont... I might get out give you a chance to find the exit, and should not spoil the enjoy this time. but it does take away some of ment. A more serious problem is 3D Monster Maze, is the best the fun. This did not happen very the fact that the ordinary user game I have seen for the Sinclair often though. This program then would find it difficult to take a ZX81. can be highly recommended and backup copy of the program. The grey and black walls of the is available for a 16K ZX81 from J. Distributor Molimerx is to be maze provide the 3D effect and K. Greye Software on its games praised in supporting his soft. the graphics make Tyrantape 4 and costs .95. "


"MICRO-GEN JOYSTICKS FOR THE ZX81 AS SEEN AT THE ZX MICROFAIR * THE MOST EXCITING DEVELOPMENT EVER FOR THE ZX81 * TURNS YOUR ZX81 INTO A TRUE PROGRAMMABLE GAMES MACHINE * FREE YOURSELF OF THAT DEAD, UNRESPONSIVE KEYBOARD * PLAY INTERACTIVE GAMES WITH IMMEDIATE RESPONSE CONTROLLER BOARD FITS INBETWEEN THE RAM PACK AND THE ZX81 (NO SKILL IS REQUIRED TO MAKE THIS CONNECTION AND IT ACTUALLY IMPROVES THE STABILITY OF THE RAM PACK) * UP TO 2 JOYSTICKS MAY BE ATTACHED TO THE CONTROLLER BOARD SO ALLOWING 2 PLAYERS TO PLAY GAMES AGAINST ONE ANOTHER * THIS ADD-ON EXTENDS THE CAPABILITY OF THE MACHINE IMAGINE THE TREMENDOUS VARIETY OF GAMES THAT NOW BECOME POSSIBLE DETAILS SUPPLIED ON HOW TO USE THE JOYSTICK IN YOUR OWN PROGRAMMES For the games presently available you will require a controller board, price: .50 and 1 joystick, price: .60. Please add .80 p&p. Games available (many more to follow, especially 2 player games) ZX Space Invaders + Space Maze .95 + 40p p&p. ZX Breakout .50 +40p p&p. ZX81 CHESS ZX NEW YORK Look at these features Fast Addictive Game Graphic display of positions on chess board Can you bomb and shoot your way out of trouble before your plane * Displays separate record of your move and the computer's crashes into the buildings.  Written in Superfast Machine Code Written in Machine Code. Different pattern each time you play Plays all legal moves including Castling and Enpassant but if an Score continously incremented illegal move is entered will answer illegal move  Records highest score and displays at end of game Six levels of play. Nine levels of play  Random weighting computer doesn't always play the same move * Simulated bombs and rockets in an identical situation  Random amount of building that is destroyed by bomb. Board can be set up to any configuration and you can even alter or PLUS ZX Reflex exchange sides in mid game Are you as fast as you thought find out with this game,  Amazing power is 10k of memory WARNING: This game has proved to be so addictive Micro Gen PLUS Chess Clock! Records and displays time taken per player accepts no responsibility for insanity, divorce proceedings, or any  Resetable function. other damage so by incurred. Now only .9540p p&p Single key entry Now only .50 + 40p p&p. If you write a program which is exceptional submit it to us and if suitable we will offer a royalty. Cheques and POs payable to Micro Gen, Dept VG, 24 Agar Crescent, Bracknell, Berks. Tel: (0344) 27317. VoxBox JAMES CENTRE The Largest Selection of Games in the World including the product that speaks for itself! Speech adds a new dimension to computing and the Mutek VoxBox, unlike most other systems, gives the capability to generate unlimited vocabulary speech from your computer. The unit is easily programmed via a parallel or serial port and a version is available for most popular computers. The principle of phoneme synthesis is used and, because phonemes are the \"building blocks of speech\", all English words and a large number of foreign language components may be easily constructed An increasing range of software is available to enable quick and easy sentence construction The hardware is supplied complete and tested with inbuilt power supply and connectors for your computer. Versions range from  for connection to PET, Apple, TRS-80, Video Genie, OSI, UK101, VIC and Acorn with no hidden extras for connecting leads, free demonstration software and excellent documentation Listen before you buy We can honestly say the quality is nearly as good as human speech, so why not call us after 6pm and listen to our computer talking through VoxBox. You may place a credit card order or a request for further information after the message. VIDEO GAMES 22 OXFORD STREET  LONDON W.1. (near Tottenham Court Road) and also at 439 OXFORD ST. W.1. (opposite Selfridges) 126 CHARING CROSS ROAD, W.C.2 (opposite Foyles) 184 REGENT STREET, LONDON W.1 (2 mins from Oxford Circus) Mutek Quarry Hill, Box, Wilts Tel: Bath (0225) 743289 78 COMPUTER & VIDEO GAMES "


"IMAGES ON AN APPLE EESE The high-resolution graphics facilities of the Apple can be used to create and manipulate shapes. This can be done on any microcomputer with highresolution graphics. However, on the Apple, shapes can be represented and stored in a special way so that they may be drawn, erased and transformed more quickly than is possible with other micros. Animation using high-resolution images can be achieved much more realistically and impressively on the Apple than on any other machine. The way in which images have to be stored when using the Apple appears rather awkward at first, but in fact it is no more difficult than any other way of Fig. 3 use the special features. The facilities needed by a programmer to create graphic effects are all available, and the user who wants to do so can create his own graphics system. The first diagram shows how a shape is represented, so that it can be stored and the special Applesoft commands can then be used to draw and transform it. The simple bat shape shown in (a) is decomposed into simple vectors which all have the same length but which point north, south, east or west, as in (b). The vectors making up the shape are then \"unwrapped\" as in (c) and are then coded. The coding table is representing and storing an image and is soon mastered If you want to achieve realistic animation, the effects that the Apple can give are amazing. No system which relies on Basic alone, possessing no comparable special features, gives anywhere near the same speed of execution. Of course, if you are more interested in creating graphics than in looking at them, you may feel that the Apple makes it too easy by doing all the interesting work, but then you don't have to given in (d), and the order in which the vectors are coded and written down is shown in (e). The coded form of the shape is to be stored in eight-bit memory locations. Since the code for each vector has three binary digits, two codes can be stored in each location while the remaining pair of binary digits in each location are both zeros as shown in (e). The resulting table of binary digits is given as (f). In (g) this table has been translated to hexadecimal and given a header and an end marker, and this is the shape table which represents the bat shape. The shape table can be loaded into any convenient part of the memory where it will not be over-written, and the address at Fig. 1 which it starts should be placed in the locations with hexadecimal addresses E8 and E9. When a shape is stored in this way, the following commands can be used. DRAW 1 ATX, Y draws shape number 1 in the shape table starting at the screen location in column X and row Y. XDRAW 1 ATX, Y similarly erases a shape. ROT = N causes a shape to be rotated clockwise according to the value of N. N = O gives no rotation, while N = 16 gives a rotation of 90 degrees. In this way, N gives the rotation in units of approximately six degrees. SCALE = M causes scaling. M = 1 gives reproduction at the original size; M = 2 doubles the size by doubling the length of each vector in the shape. The maximum value for M is 255. With these commands, animation can be achieved by repeatedly establishing a position, drawing the shape and then erasing it. Figure two was produced by the program: 10 HGR : HCOLOR = 3 20 FOR I = 1 TO 3 30 X = 50* I: Y = 100 40 DRAW I ATX, Y 50 NEXT I Figure 3 resulted from: 10 HGR : HCOLOR = 3 20 ROT = 0: SCALE = 24 30 FOR I = 1 TO 3 40 X = 50* I: Y = 70 15*1 50 DRAW I AT X, Y 60 ROT = 64-3*1 : SCALE = 24-4*1 70 NEXT I Fig. 2 By Gary Marshall "


"SOS Missile Command Multihead Destructors destroyed city SOS Missile Command Cluster Mines sighted SOS Missile Command Plasma Projectile assault SOS Missile Command Satellite Bombs in range. SOS Missile Command. Megon Annihilator destroyed further city.. SOS Kansas  'COMMAND' CONTEST Computer Fair-Earls Court April 23-25 missile HD SCOREN Together, Mike Chalk and Kansas bring you not just another Arcade game ... an EXPERIENCE! YOU command the ground-to-air missiles to save the cities from total Alien destruction, progressing to TEN levels of difficulty from not-to-easy to bloody impossible! Multiple displays with five types of Aliens and Satellite Bomber. Each type of Alien attacks on a different trajectory, even splitting and changing course without warning. Based on the Arcade game of the same name, this is easily the finest computer game of its kind available today. It demands quick responses and no small amount of skill to overcome the Aliens even at the lower levels of play. As the game proceeds, so does the risk of total ahiliation, giving at last, a very, very competitive game indeed, and one which will satisfy even the very skilled gamesman. Very spectacular explosions and sound effects complete the realism. Infinite missile 'sight' control giving movement in every direction. ONLY from Kansas-.50 Programs for the TRS-80 and Video Genie. All prices are Vat paid and post free. Same-day first class return post service. All software in stock and fully guaranteed as we are the actual publishers. Free catalogue upon request. ACCESS & BARCLAYCARD WELCOME Kansas City Systems, Unit 3, Sutton Springs Wood, Chesterfield, S44 5XF. Tel. 0246 850357 ARE YOU LOST IN THE WORLD OF ELECTRONICS? HOME RECORDING -RADIO HAMS E PROJECT ELECTRONICS MICROCOMPUTING THEN THE NEW STYLE HOBBY ELECTRONICS CAN SHOW THE WAY! April issue out Price only 70p NOW! BUY YOUR COPY TODAY 80 COMPUTER & VIDEO GAMES "


"PLAYING YOUR CARDS RIGHT method of wiring can either be by soldering singleor multi-stranded, insulated conductor or by wire-wrapping using the special cable. In the case of high density boards the most satisfactory means of making connections is to wire-wrap, and sometimes it is the only practicable method. The idea behind this process is that with extended pins on the chip holders the wire can be wound around, either manually or by the use of a hand tool, to make the connections. It means that the holders, which previously had to be spaced, can now be placed almost on top of each other, thus making the size of card required for the design much smaller, saving space and money. WRAPPING THINGS UP The eurocard is a versatile aid to those of you building your own circuits. Unlike other types of matrix board it has been designed especially for the use of chips — but it can also be used for discrete components. The eurocard comes in various sizes and designs depending on the supplier and the use to which it is to be put. Some types allow for an edge connector and others for rack mounting. The most commonly used by hobbyists just has a double row of holes at each end of the board to allow pins to be inserted and wired to. The tracks, which run on both sides of the board, are designed to accept chip holders of any standard size. You should be prepared, however, to buy special wire-wrap holders if you are using chips with more than 20 pins, as these will take up all of the solder pads on some of the boards. It is possible, in this case, to solder wires on to the pins of the holder to make connections on the underside of the board, but this is not recommended. Most boards have a pair of power lines which are placed conveniently across the top and bottom of the card where the chips are designed to go. By a single short link to the chip the necessity of individual wiring is done away with. Be certain though to make these connections to each chip first as it is possible to mistake later wiring for these. If I am using one of the eurocards for a prototype circuit I lay it out in an orderly manner with chips evenly spaced across the board making it easy to see where I have already wired connections. This, however, may not be possible with, say, a memory board which is required to fit into a very restricted space but may, nonetheless, have a large number of chips of various sizes. For a low density card the There are, as I said, two slightly different methods of wirewrapping. The first, and easier, is to take a very light gauge insulated wire, strip it and wind it around the base of the pin. Do not wind over the top of a previous solder as you may need to unwrap it if you have gone wrong. Even so you should wind the wire around a minimum of three times, so that if there are more than two connections to be made on the same pin there is enough space left. There is a tool specifically designed for this purpose, looking very much like an inverted needle. There are, however, a number of different models so try them before picking one. Using the wire-wrap tool makes light work of an often difficult job. The battery operated tool cuts the job time in half if you know how to use it correctly. The idea is to wrap an insulated wire around the pin at a very high speed but low torque. The square edges of the pin cut through the insulation and a cold forged weld is formed. This is a great improvement on the soldered contact although the number of times you can remove the join to remake it is limited. As with the other methods, the first connections made should be the power lines. You can then be sure that it is a chip that has gone down and not just lack of power. It is a good idea to loom the power lines, as it is with data or address lines. That is to say, a single is taken from the power point on the card to the first pin, terminated, and then from that pin to the next, and so on and so forth across the board. Beware of over-loading the conductor if you are using too many chips, or high-powered ones. Designing your own circuits, building them and getting them to work can be very rewarding. but unless you have an idea of how to go about it you can be stumped very easily. By choosing the right method you can cut out a large amount of the hassle involved. Experience will tell you which way is best. BY KEITH MOTT "


"Practical Computing and Your Computer present... THE April 23-25, 1982 Earls Court, London Computer Faire som Friday & Saturday: 10am-6pm Sunday: 10am-5pm Personal computers Home computing Small business systems Admission .00 adults .00 children under 16. At The Computer Fair you can see and compare an enormous range of personal and home computers. Find out what they can do and which one would suit you best. Talk to the experts and discover for yourself how much-or how little-you need to spend. Choose from an amazing abundance of software programs and packages, cassette units, VDU terminals and scores of computer games. Swap your views and know-how with hundreds of other home computer enthusiasts and find out a whole lot more from computer professionals. AURER Plus-The Micro Mouse Contest Come and watch the incredible ingenuity of computer controlled \"mice\" and how they find their way (or not!) to the centre of a maze. The knockout heats and the Euromicro British Final can all be seen at The Computer Fair! Bring the whole familydon't miss this opportunity of bringing computers into your everyday life. WS Bringing computers to everyday life 82 COMPUTER & VIDEO GAMES "


"SUPERMARKET ADULT ONLY MIND ROUTINES VIDEO CLUB! Ring day or evenings cheap ratel equal piles. In the morning they all awoke and divided the loot into four equal piles. This time it went exactly. Nobody commented on the diminished piles because they were all guilty. They all then went their separate ways picking up their hidden loot on the way. When the last man to awake in the night counted his loot he found he had a multiple of 10 bags. What was the smallest number of bags they could have stolen? David Simmons, of Colborne Way, Worcester Park, Surrey and Mrs M. Dickson from Grove Avenue, South Kirkby are this month's champagne winners. Answers to March problems on page 9. Four thieves broke into a bank and stole a number of bags of coins. They decided to lay low for a while and hide in a wood. In the middle of the night one greedy thief woke up and decided to take his share of the loot. He divided the bags into four equal piles and found he had one bag left over. So he took this spare bag and one of the piles and hid them away for himself. Each thief in turn awoke and decided to take his share not knowing some had already been taken and each in turn found one spare bag, which they also kept, when dividing into four 0373: 830563 or send coupon to: VIDEO CLUB 1. DREWSTEAD RD., LONDON S.W.16 Please send FREE details, I am over 18 NAME ADDRESS IPHONE Please remember to fill in your telephone number NEVERA CROSSWORD 81-1K starter pack Twelve programs on cassette written for the new user to demonstrate the versatility of the ZX81. Seven exciting moving graphic games including: Invaders, Tank-Shoot, Subsearch and Road Race: A sound generation program is also included. Orders despatched on high quality cassette by return, .90 with order to: Seconddation Tamworth, Stats 877 2LL ACROSS 1. Concerning advertisement just can't be edited (4,4) 5. Nudge in the RAM (4) 9. In which 0 9 A F says it all (3) 10. Asking about quinine R.G. Compound (9) 11. Star games (9) 14. Headless feline print appendage (2) 15. Energetic pursuit of tail-less micro (2) 16. Programmed literature? (1, 5, 5) 19. White power leaders in office computer equipment (2) 20. Personal assertion in middle of time (2) 22. Stray labs confused laser output (3, 5 24. Devoted as a slave peripheral (9) 26. Computers kit containing slalom equipment (3) 27. Bridge player in a stew (4) 28. Treasonable output (8) DOWN 2. Odds or their opposite (5) 3. SIN (X) * SIN(X) +COS (X) **2 (3) 4.  on the palace display (6, 7) 6. Charge on logical alternative constellation (5) ...LATEST SCORE -LATEST SCORE -... MZ 80K -* PET VIDEO GENIE: --ZX 81 OWNERS .... FOOTBALL POOLS PLANS COMPUTERISED CHECKING CHARTS Superb new programmes now available Write for details soon you could 999 be checking your favourite plan fastHours POOLSOFT 17 Blatchington Rd. Seaford. E. Sussex BN26 2AB. Tel. (0323) 890604 7. Northern genie mixed up the driving force (6) 8. Noisy plugs (4) 12. Bat round print position (3) 13. Ate up the anticipated advent (3) 15. Programming language on the back of the disk (2) 16. Allied Press paper contents (2) 17. Way amongst the deviations (3) 18. Print measures in the dodgem slots (3) 19. Restricted graphical view of a bawl on a squall (6) 21. Civil servant surrounds poetry such as ASCII and EBCIDC (5) 22. Have a care about a Grand Prix (4) 23. To know the reward from a fruit machine (5) 25. Pixel lady (3) nascom-2 Software required Imaginative Graphical Games Programs Backgammon Grand Prix 15.00 Speedway BK 5.00 Dodgems Computer Darts Downhill Skier Inter Solar Software Star Wars 32K E10.00 X-Wing Star Bantle 161550 Beam Me Up Scotty 16K 5.00 Alien Bombardment BK 4.00 FUTURA SOFTWARE 63 Lady Lane Chelmsford Essex CM2 OTO COMPUTER & VIDEO GAMES 83 "


"SUPERMARKET SHARD VIDEO GENIE-TANDY OWNERS JOYSTICKS Atari Joystick A GUIDE TO THE LOW-COST COMPUTERS A, interfaced for your computer. Will work with all the Big 5 Joystick Games Tandy Model 1 Level 2 .50 Video Genie .50 Single Joystick LE STICK The ultimate Joystick. Real Home Arcade Action. Brings those Joystick games to life. Tandy Model 1 Level 2  Video Genie  Tandy Colour Computer  Single Joystick JOYSTICK GAMES For use with Galaxy Invasion above Attack Force Robot Attack Cosmic Fighter Meteor Mission ALL L9.95 TANDY COLOUR COMPUTER OWNERS Now available Chromasette Magazine. A monthly tape of at least 6 programs Single copy .95. 6 month sub.  12 month  VIDEO GENIE & TANDY MODEL 1 & 3 Now available in UK-Cload Magazine. America's monthly program tape for games orientated people. Why pay high prices when each month you can receive a cassette with at least 6 programs. Latest issue includes: SPACE WAR Fight the enemy as he flies at you CATERPILLAR Similar to the arcade game \"Centipede\" ELEPHANT ADVENTURE Full length Safari adventure program Plus 4 other programs Single cassette .75 6 month subscription .50 12 month subscription .00 All programs for Model 1 Level 2 Most for Model 3. Over 44 back issues available plus many programs for Level 1. Post your order to MICRODEAL, Deal House, Bridges, Bodmin, Cornwall. ALL PRICES INCLUDE TAX & POSTAGE ATOM Cambridge based Acorn Computers manufactures the Atom machine which has a memory capacity of 2K, but it can be upgraded to 12K. It must be plugged into a television and is available in either kit form or ready built. As a kit it costs  for the 2K computer or  for the finished product. For a more powerful system, 12K, the price stands at  (in kit) and  completed. Acorn also makes the Systems 1, 2 and 3 which cost between  and  MICTROTAN 65 Tangerine Computer Systems produce this machine for games and personal use, like household accounts. It comes in kit form and is expandable from an initial 1K memory up to 48K RAM. The Microtan 65 costs .35 for the 1K kit, or .85 assembled from the Ely based firm. NASCOM There are two Nascoms available at the moment, both can be used for business and games. The Nascom 2 is the more powerful of the two with 8K RAM and with a Basic interpreter, It can be bought in kit form and off the shelf complete. The kit is  for 1K RAM and  for the finished 1K product.  will secure an 8K kit. Nascoms are available from Warwick-based Lucas Logic. APPLE The Apple has a solid software base for both business and entertainment applications. The machine comes with a memory capacity ranging from 8-48K. You can buy joysticks and paddles to plug in for use with computer games. Colour graphics can be used with a colour television. The 48K machine costs  and is obtainable from Apple Computer U.K., formerly Microsense which is based in Hemel Hempstead, Hertfordshire. NEWBRAIN This is a hand-held computer unit which is at the low end of the price bracket. For 2K RAM you pay  upwards and it is expandable to 20K of memory. Hobbyists often opt for this machine because of its low cost and it is used for general business and for playing games. An expansion unit is available which supports floppy disc drives, a printer and a visual display unit. It is available from the Grundy Group  PUCKMAN ACORN   REQUIRES 12K RAM. The popular ARCADE game of a mazo full of hungry ghosts. Can you at all the dots and stay ALIVETI in danger wat a star, the chase reverses. Utilises Graphics mode 4 for high speed high resolution action.Plus SOUND EFFECTS.Great FUN ON A GOOD QUALITY C12 cassette. ONLY IS Ino.Pap micromania 14 Lower Hill Rd.EPSOM, SURREY. ATARI 400/800 Most of the software for the Atari microcomputers are games or educationalwith business applications only recently being introduced. The basic 400 with 16K RAM costs  direct from Atari's UK distributors, via London-based Ingersoll Electronics. The 32K version sells for . Peripherals for the machines, like disc drive units and cassette recorders can also be obtained from Ingersoll for  and  respectively. The 800 is expandable to 48K and the 16K machine sells for . SPECIAL OFFERS * GENIE I 16k computer with SOUND for one month only  OFF now  *VIC-20 With each computer a 3k Ram Pack at half price plus free dust cover *D.AL 16 colours -stereo sound-high res graphics 48k RAM 24k ROM  Free Cover Free ProgramsFree Paddle Free Cassette * SHARP 48k computer  Free Programs Free Dust Cover VAT INCLUDED in above prices OHIO SCIENTIFIC Ohio Scientific (OSI) makes the Superboard which is aimed at the hobbyist market. Its memory capacity starts at 4K RAM and is expandable to 32K if you buy the add-on board. Other machines in this family include the Challenger 1 and 4. These are essentially cased versions of Superboard. The Challenger 4 is the cheapest of these at  and includes colour and sound options. BARCERYCARD everyman Computers 14 Edward Street, Westbury. Wilts. Tel: 0373 864644/823764 CREDIT AVAILABLE ON REQUEST BBC MICRO COMPUTER The computer adopted by the BBC to sell in conjunction with its forthcoming series is based on the Acorn Proton. The BBC has developed its own Basic to be used on the machine. Minimum memory is 16K RAM, maximum being 32K. Present plans for the machine are dual purpose, both business and games. Optional extras include joysticks, paddles, disc drives and a cassette for tape loading. Price is put at  for the 16K computer and  for the 32K version. PET Made by Commodore Business Machines, the Pet ranges from 8K RAM to 32K RAM. It is used mostly by small businesses for general applications but has a hefty hobbyist following. It is available from Commodore of Slough at a starting price of . Compatible peripherals are available for the Pet, including disc drives, cassettes for loading tapes and printers. ATOM Adventures (12K): Atom Adventure (difficult) .75 Pirate Island (very difficult) .75 Write Your Own (tape & manual) .75 Action Games (m/c code, lower text): Chaser (mode O) .75 Colour Invaders (mode 2a) .75 Disassembler (3K) .75 S.A.E. for details: HOPESOFT, Hope Cottage, Winterbourne, Newbury, Berks. RG16 8BB. DAI This is a personal computer made by Data Applications for both business use and home entertainment. The U.K. system (it is made in Belgium) has 48K RAM as well as full colour and sound commands. Data Applications is based in Cirencester, Gloucestershire. The 48K system now costs . SHARP MZ-BOK Popular with both business and home users, the Sharp's memory capacity starts at 16K and has a top limit of 48K. It comes with a monitor and a cassette recorder built onto the keyboard unit. Disk drives are also available. Manchesterbased Sharp Electronics have a recommended retail price of  for the 48K unit. 84 COMPUTER & VIDEO GAMES "


"SUPERMARKET CORES A JAILABLE IN THE UK ZX-81 CASSETTE ONE \"I had your Invaders React cassette . I was delighted with this first cassette -P. Rubython, London NW10 \"I have been intending to write to you for some days to say how much I enjoy the games on Cassette One which you supplied me with earlier this month. Please let... into the secret of your first time load every time! E, H, London SW4 CASSETTE ONE SIDE ONE 1K MACHINE CODE PROGRAMS React, Invaders, Phantom aliens, Maze of death, Planet lander, Bug splat, Bouncing letters. CASSETTE ONE SIDE ONE 1K BASIC PROGRAMS I Ching, Mastermind, Basic hangman, Robots CASSETTE ONE SIDE TWO has large screen versions of Invaders and Maze of Death, ready for when you get 16k All on Cassette One for .80 SHARP PC-1211 The smallest computer in the Sharp range. Sharp classifies it as a pocket computer and it is programmable in Basic. It also has a cassette interface for loading and costs upwards of . SINCLAIR There are two types of Sinclair's microcomputer available for under . Sinclair really brought the microcomputer into the home. The machines are ideal for learning the rudiments of computing but are limiting graphically. The ZX80 has 1K of memory and is expandable up to 8K, but is no longer in production. The ZX81 sells for .95 for 1K in kit form or .95 ready assembled. The 16K RAM packs costs .95. TI-99/4A This computer has recently been re-launched by Texas Instruments. It consists of a separate keyboard with graphics facilities in full colour and now plugs in to a U.K. television. Software available for it from Texas Instruments is mostly business and educational but the firm has recently introduced a bundle of games to run on the computer. It has 16K RAM and uses tapes, discs or plug-in games cartridges. You can buy one of these from Bedford-based T.I. for  or from your local dealers. CASSETTE TWO just out, ten 16k Basic games. OTHELLO, AWARI, LASER BASES, WORD MASTERMIND, RECTANGLES, CRASH, ROULETTE, PONTOON, PENNY SHOOT, GUN COMMAND. All on Cassette Two for  Recorded on quality cassettes, sent by first class post. From: Michael Orwin, 26 Brownlow Rd., Willesden, London NW10 9QL. SORCERER The Exidy Sorcerer is a home computer with a sizeable games following but it is one of the more expensive of the microcomputers, costing upwards of . Memory amount ranges from 48K to 55K and there is a plug-in ROM pack for extra capacity. Disc drives and visual display unit are an additional cost. Sorcerers can be obtained from a Cornish firm, Liveport of St Ives. VIC-20 The VIC is the much-publicised baby of the range of microcomputers from Commodore of Slough. At  it is one of the cheapest. Deliveries to dealers have just started. The VIC has full colour graphics on a colour T.V. and there are joysticks available. Although Commodore are plugging the business use of the machine it is tipped to be a hot games computer because of its colour graphics and low cost. TANDY TRS-80 Tandy's TRS-80 Model 1 is a machine which is often used for games and is well-supplied with software for both entertainment and business applications. Its memory capacity goes from 4K to 16K but there is an expansion unit available upgrading it to 48K if you want the extra memory. The Model 1 is the cheapest of the Tandy range. The Model 1 costs  but comes complete with a monitor to use as a V.D.U. and a cassette. The Model III is an integral unit made up of a keyboard, 12\" screen and two slots for 5]\" discs. It costs from . VIDEO GENIE The Genie is made by E.A.C.A. and is a popular games machine. It is compatible with the Tandy TRS-80 Model 1. With 16K to 48K RAM there are disc drives available. The basic unit costs from  and is available from Lowe Electronics of Matlock in Derbyshire. TRS 80 VIDEO GENIE SOFTWARE QUALITY SOFTWARE AT A FRACTION OF THE USUAL PRICES SEND S.A.E. FOR COMPREHENSIVE LISTS J. T. WILSON, 9 COTSWOLD TERRACE, CHIPPING NORTON, OXON ADULT GAMES !! ZX81 1KON CASSETTE o Can of Worms  8 GAMES ACNE, VASECTOMY, SMUT, DOLE, HITLER, ROYAL FLUSH, REAGAN, Ps & Qs Love & Death  8 GAMES SEDUCTION, CONCEPTION BIRTH, RUBIC'S PUBE, ON THE JOB POX DEATHGOD @ The Bible  10 GAMES GENESIS, ADAM & EVE, NOAH PLAGUES OF EGYPT, EXODUS, HOLY MOSES SODOM DAVID GOLIATH, JONAH, BETHLEHEM all prices include pap, soundtracks & Full notes AUTOMATA LTD. (V),65A OSBORNE RD, PORTSMOUTH, HANTS, PO5 3LR TELEPHONE (0705) 735242 TELEX 86626 GENIE 1 The replacement computer for the Video Genie is now available. The Genie 1 is an upgraded version of the Video Genie and has full upper and lower case, a machine language monitor, additional Basic, has a sound unit and is cassette based. It is being aimed at the serious hobbyist market and costs . A disc version is available, called the Genie II and sells for  for the unit,  for the expansion box needed, and  for each disc drive. TANDY TRS-80 COLOUR COMPUTER Tandy's latest addition to its range of computers is the Extended Basic Micro Colour Computer (or TRS-80 Colour Computer for short). It is available with either 16 or 32K of memory and costs . The actual computer unit consists of a keyboard which can be plugged into any television set. It is aimed at both business and games users and Tandy has bought out a variety of instant loading games program packages for the machine. Joysticks needed to play some of the games are extra and cost .95 a pair. The colour computer can be obtained from Tandy stores nationwide. U.K. 101 This machine comes in either kit form or ready built with memory capacity of 4K to 40K (with an expansion board). It contains television and cassette interfaces so you don't need a V.D.U. The U.K. 101 is a popular computer for playing games and there is a lot of software around for it. The kit costs  for 4K, ready built it sells for  DO YOU PLAY TV GAMES? It could cost anything up to  to own your own comprehensive library of cartridges for your TV games console. We have such a comprehensive library for most systems, and are prepared to offer this facility to you at low daily rentals, with the option of purchasing at Special Discount Prices those cartridges which give you most pleasure. For further details please send a large S.A.E. to E&E ENTERPRISES, P.O. BOX 8, SALTASH, CORNWALL PL12 6 YU. COMPUTER & VIDEO GAMES 85 "


"SUPERMARKET A beginner's guide to plain iarnon ZX81 16K RAM cassettes GAMES OF SKILL & TACTICS NASTY INVADERS .95 Get them before your bosses get you! NASTY MOUNTAIN .95 VERY NASTY MOUNTAIN 15.95 Adventures on your way through the Mountain. If that's too easy, try the Very Nasty Game with its 16 Levels of Play JUSTIFY THAT BUSINESS EXPENSE PETTY CASHIVAT .00 Enter Date, Narrative and Gross Expenditure for each Cash Purchase. Classifies into 20 SubHeadings and 13 Main Headings and gives Gross. VAT, Net and Exempt Subtotals and Totals. It's so good, we use it ourselves. VAT BOOK INPUTS .00 As the Petty Cash VAT Program but with the facility to add in your Cheque and Standing Order Items to give inputs Bottom Line Totals. . all programs are recorded twice check-loaded before despatch user program test facility prices include VAT and P&P Cheques P.O.s to: GILTROLE LTD., DEPT CVG3, PO BOX 50, RUGBY, WARKS, CV21 4DH SOFTWARE Suitable for use on Atari Computers) SCREEN PRINT CASSETTE At the press of one switch, prints the contents of the screen (Graphics 0 only), on your printer (P. 1.). will print disassembled machine code if using de-bugger. Very useful for those large machine code listings when no source code is available. .50 .P.P. included for UK, only LISTING 1 A machine code listing and instructions of improvements only, to space program cassette (The one in which you defend the surface of the moon.) .50 P.P. included for U.K. only. Requires Assembler QUAIL HOLLOW ELECTRONICS SCHOOL LANE, SHARNFORD, LEICESTERSHIRE, LE10 3PU ZX81 GAMES HIGH QUALITY LOW COST SOFTWARE (ABSOLUTELY NO RUBBISH) GAMESTAPE 1, for 1K, only .95 10 Games incl. Asteroids, UFO, etc GAMESTAPE 2, for 16K, only .95 Starfighter, Pyramid, Artist. GAMESTAPE 3, for 16K, only .95 Catacombs... A Graphics Adventure. GAMESTAPE 4, for 16K, only .95 3D Monster Maze... Unbelievable Graphics. Cheque/P.0.s to J.K. GREYE SOFTWARE, Dept CVG, 16 PARK ST., BATH, AVON BA1 2TE. ADVENTURE A type of game in which the player has to take a character role and retrieve a number of treasures or objects by a trial and error process giving instructions to the computer. The \"hero\" (or player) encounters a variety of hazards often taking the form of dangerous monsters, wizards and animals. Some adventure games are so complex that they take weeks, or months, to solve. ALGORITHM A process or set of rules to carry out a task or solve a mathematical problem. ARRAY A series of items (data or information) arranged to form a meaningful pattern. ARROW KEYS The keys on a computer keyboard marked with arrows. Used for moving the cursor across, or up and down the V.D.U. screen. ASSEMBLY LANGUAGE A language built up with memory codes designed to make programming easier. BUG A slang term given to a mistake in a computer program which prevents it from working. It can also refer to a mechanical, electrical or electronic defect in a computer. BYTE A term to measure a number of Bits (Binary digiTS), usually eight bits to a byte. CAPACITOR An electronic component. CHARACTER STRING A sequence of characters in a row. CHIP A tiny piece of silicon which holds all the components that make up a microprocessor. COMMAND In writing programs this word refers to an instruction word which specifies an operation which the computer must perform. COMPUTER LANGUAGE Languages are used to make the computer per form operations. They consist of instructions or commands. There are different types of language for carrying out different tasks. CONVERSATIONAL SCROLLING Data displayed on the screen, involving step-by-step communication between the user and the computer. DEDICATED CHIP A chip (microprocessor) which has been specially programmed to perform a single or special group of applications, e.g. computer games. ROMs are usually the means by which dedicated chips are developed DISC A magnetic storage device. It can be either a hard or floppy disc. Hard discs can usually store more information than floppy discs and are used with mainframe computers. DISC DRIVE A unit which is connected to the computer, used for loading the information stored on discs into the computer. DISC STORAGE The method of storing information on discs as opposed to cassettes. EUROCARD A type of printed circuit board suited to circuits with a large number of chips. FLOATING POINT This is a notation used for the calculation of numbers in which the arithmetic point, binary or decimal, is movable but not necessarily the same for each number. FUNCTION A special purpose or characteristic action. GRAPHICS The name given to pictorial representation of data. HARDWARE The general term given to all pieces of electronic and mechanical devices which make up a computer system, i.e. the actual machines. HIGH RESOLUTION GRAPHICS A method of using Basic commands to move a drawing head to any position on the screen and drawing a line between two specified points. This facility is available on several makes of microcomputer. These graphics can be recreated in greater detail and to a higher degree of accuracy. INPUT Information (data) fed into a computer. INTEGER A number which does not contain a decimal point, i.e. a whole number. INTERACTIVE A word used to describe a system which is capable of real-time man-machine communications. K Abbreviation for kilobyte. KILOBYTE A measurement of memory capacity. 1024 bytes of memory. So 8K is equivalent to 8192 bytes. LANGUAGE See \"Computer Language\". L.C.D. (Liquid Crystal Display) A display containing liquid crystals which light up when electricity touches them. Used in calculators and watches, L.E.D. (Light Emmitting Diode) Provides a simple display and consists of an electron tube which lights up when electricity is passed through it. Used MONOPOLY TANDY V. GENIE Computer challenges you at Monopoly as a For up to 6 players including computer) Unique system featured whereby computer detects the skill of best player than adjusts its skill automatically to match that player Computer's game at highest level is strong  Every game different, close, exciting and chal longing  Game data can be saved on tape to continue game at another time. Easy fool-proof entry ideal even for children to  2 versions of Monopoly included. 'Standard as to rules. Popular slight variation to rules.  Many, many hours of fun for all the family, On tape for the VIDEO GENIE and TRS-80. Model 1 & 3. Level 2. 16k .95 inclusivo COMPUTICS MICROSOFT 1 BELL LANE, WHEATLEY, OXFORD OXS 1XY 86 COMPUTER & VIDEO GAMES "


"SUPERMARKET Quality software INVADERS beginner's guide to plain jargon Also T GAMES Five games running in TRAMI SPECIAL OFFER ZX81 168 RAM Pa u guwanted with FREE Galaxy invaders se 2.00 NEWIVIC INVADERS NEW! speed full colour sound effects no extra RAM needed Computer grades and instructions BRIDGE SOFTWARE G) . E SA set VIC 20 : VIC 20 Batty BatArcade game. Guide the swaying balloon through the maze without bursting. Three levels of difficulty and the balloon sways faster as your score gets higher. Full sound and graphics. On quality cassette for basic Vic 20.34K Send cheque or P.O. value 5.95 to: G. MOORE, 4 ACKERS ROAD, WOODCHURCH, BIRKENHEAD, MERSEY SIDE as an alternative to liquid crystal. LOAD Putting information from auxiliary storage into internal storage of a computer. It can be either a complete program or any data. When you load a program you put the contents of the program into the computer's memory from storage either on a disc or a cassette. LOOP A Basic function referring to the repeated execution of a series of instructions for a fixed number of times. MACHINE CODE The term used to refer to symbols or numbers assigned to parts of a machine. MAINFRAME COMPUTER The jargon work used to describe a very large computer. MEMORY A device which information data can be copied into, stored, and later obtained from. MICROCOMPUTER A tiny computer (as the name suggests) consisting of hardware and software. The main processing blocks are made of semiconductor integrated circuits. MINICOMPUTER This is a computer which offers memory ranging from 4K to 64K and are characterised by giving a higher performance than microcomputers or programmable calculators. MONOCHROME COMPUTER DISPLAY A display screen used in a computer which shows a picture in one tone or black and white only. NUMBER CRUNCHING The operation in computing which carries out the arithmetic and logical processes which information has to go through. NUMERIC KEYPAD This is a section of the keyboard consisting of a small number of keys. They differ from alphanumeric keys because the numeral, decimal point, and enter keys transmit unique escape sequences. OUTPUT Data which is emitted from a computer system, either on the screen or in printout form. PEEK A statement used in Basic which allows you to read the contents of a specified memory address. PERIPHERALS Equipment which is used with a computer, e.g. printers, V.D.U.s and disc drives. POKE An instruction used in most versions of Basic allowing you to store integers in a specific place in memory. R.A.M. (Random Access Memory) This is a memory chip which you can load programs and data to and from RANDOMISE A Basic command referring to the procedure for making numbers, data, or events occur at random. RANDOM NUMBER A number selected at random from an ordered set of numbers. REAL TIME This is on-the-spot computing when the operation is performed during the time an event is taking place in time to influence the result. ROM (Read Only Memory) A memory chip which can only be read from and not written into. ROUTING Is the method of calling up on screen information in Prestel. On the back of each Prestel page is information in the form of lists of numbers which the computer searches to find the number of the page the user wants to move to next. ROUTINE A set of coded computer instructions used for a particular function in a program. SOFTWARE Another name for computer programs. It can also refer to computer documentation. STATEMENT an instruction in a computer program. STRING A connected sequence of characters, words or other elements usually symbolised with the dollar sign. SYNTAX The name used to refer to sentence structure rules of programming language. VALUE The numerical quantity of a data element, and is the number assigned to a variable. VARIABLE A symbol whose numeric value can be changed at all times. It is used when writing programs. V.D.U. (Visual Display Unit) A unit which is capable of showing data. They look like small televisions. ASSASSIN For 3.5k VIC 20 .99 Shoot the men in the head before your contract runs out. Send cheque or PIO payable to: Gibson & Harvey Enterprises 49 St. Leonards Road, Bexhill-on-Sea, East Sussex. ZX81 16K SOFTWARE Wartrek, Golf and Minefield on cass. .00. J. O'Connor, 5 Tennison Close, Bolton-Le-Sands, Lancaster. Tel: (0524) 822648. AD INDEX 10.11 Kansas City Systems Kayde Electronic Systems Acorn Computers Adda Addictive Games Arton Artic Computing Avalon London Computer Fair Lowe Electronics 22 50 Microage Microgen Molimon Bug Byte Butler Currie & Hook Calisto Computers Caps Ltd Compshop Computershack Computers For All Computersoft Ltd Control Technology Croydon Micro Centre Nick Hampshire Program Power DKtronics Quicksilve Essential Software Co. Fuller Micro Systems Silica Shop Silversoft Sinclair Research Sinclair User SRS Microsystems 73, 74, 75 Games Centre Gemini Electronics Hewson Consultants Hobby Electronics Holdco Ltd Tiny Publishing Co bek Soystems IPC Business Press 82 Woodland Software COMPUTER & VIDEO GAMES 87 "


"WOODLAND SOFTWARE WE ARE ONLY 30 MINUTES FROM LONDON AND ONLY A FEW MINUTES FROM YOUR POST BOX. MAIL ORDER MICROCOMPUTER SUPPLIES FOR THE APPLE SO WHY NOT TRY OUR MAIL ORDER SERVICE FOR ACORN ATOMS, VIC 20s, ATARI 400 and 800. COMING SOON BBC MICRO. Wizadry 48K P .90 Epoch 48KM 20.70 Galactic Attack 48K P 17.25 Copts & Robbers 48KM C20.70 Doom Cavern 48K VA Outpost 4BK M .25 Odyssey 48K 1 .25 Beer Run 4BK M .25 Tank Attack Death Run GK 1A 1265 Gorgon GBK M 23.00 Wilderness Campaign 48K A 1265 Sneakers 4BK M E17.25 Wilderness & Dungeon 48K VA 120.70 Gamma Goblins 48K M 17.25 Mission Asteroid 48K M .50 Autobahn 48KM 17.25 Mystery House 48K M Orbitron 48KM .25 Wizard & Princess 48KM .70 Pulsar 40KM .25 Cranston & Manor 4K M 621 85 Space Eggs 48KM .25 Hi-Res Football 48K M Phantoms Five 48K M .25 Hi-Res Soccer 48K M .25 Cyber Strike 48KM .00 Hi-Res Cribbage 48KM E14.37 Star Cruiser 32K M .95 Missile Defense 48KM .25 Both Barrels 48K A 14.95 Sabotage 48KM E-Z Draw 3.3 48K A 28.75 Gobbler 4K M Higher Graphics il 48K VA 21.85 Threshold 21.85 Soft Porn Adventure .25 Superscribe 4K M Ulysses & the Golden Fleece 21.85 Expediter il 48K A .25 \"Revised Version A Applesoft -Integer UK distributors for H/A-Integer & Applesoft Sir Tech Inc M-Runs on any Apple Trade enquiries invited P. Requires DOS 3.3 All software is disc based. All prices are inclusive. On multiple orders of 3 or more programs P&P is FREE: please add 50p P&P on orders less than 3. A list of our full range of software is free on request from: Send large S.A.E. for details or phone Romford 752862 or 60725. Access and Barclaycard accepted. Computers for A11 Romford Computer Shop 72 North Street, Romford, Essex. WOODLAND SOFTWARE 103 Oxford Gardens, London W10 6NF. Telephone: 01-960 4877 Inside BASIC Games E11 50 SHARP MZ8OK (48K RAM) APPLE Apple 48 Disk drive with controller Disk drive without controller Parallelprinter interface PRICES Program the Z-80 Your Fur Computer 6502 Applications Book E11.95 .75 10.25 RING FOR OUR THE SYMBOL OF VALUE SUS SUPAVALUE NASCOM KITS 610.00 18.00 SHARP PC1211 Interface Colour card BASIC Business Software .05 Apple Writer BASIC Computer Games ES.95 PASCAL language system BASIC Como Prop 8.55 Bank BASICA ACCESSORIES teaching guide ES.95 FOR APPLE CP/M User's Guide (Not Apple Manufacture) Osborne 10.10 TOK RAM Card Game Playing with BASIC .20 280 process card CPM di manual 90 column board Instant BASIC 19.75 162.50 Display switch C1800 Micros Velo Slot Extender BOOKS C10.10 Microsoft BASIC .75 Computers for Everyone 6.00 More BASIC Games Mostly BASIC Pror Apple il Ed Applica Apple 7.95 Apple BASIC Duta Mosty BASIC Applies PET .95 Make of Programming Micro-compungin Micro 6502 18.05 your Business 14.95 YOU'LL VALUE OUR EXPERIENCE YOU'LL VALUE OUR PRICES NAS SY51 SOFTWARE NAS-SYS 1 ROM NAS-SYS EPROM ZEAP 2.1 NAS SYSEPROM ZEAP 21 for NAS SYS on tipe BK microsoft basic in ROM 112.50 626.30 BOARD LEVEL 122.50 NAS-SYSTless PIO .00 18.00 23850 BGBEN BEGON BBB BOB EBBE GEBE BOOB BBBB gee ATARI CASED SYSTEMS Nascono RAM KRAM 16 user RAM 32K user RAM KRAM POWER SUPPLY 380 3600 .50 .25 800 Computer 400 Computer Recorder D Drive 16K RAM Joysticks pair) Blank Dukettes 151 Assembler Editor 5 SUPAVALUE MEMORY CARDS RAM memory card with 16K RAME72.00 ATARI 800 (16K RAM) SRS MICROSYSTEMS 690.00 .50 with RAM bound Additional 16K RAM Additional 32K RAM VO BOARDS boards for PO, CTC XUART Surades ROM Missile Command ROM Asteroids (ROM Invitation to Programming (1) RING FOR OUR SUPA LOW PRICES 161 Bramy Road, Oakwood, London N14 AXA Telephone: 01-363 2060 Closed Monday YOU'LL FIND SRS SUPAVALUE 40:50  .60 Touch Typing Conversational French Conversational German Conversational Spanish BRAMLEY ROAD La PO for above CTC for above UART for above DISC SYSTEMS Nacoming drive SOKB FOCard Nascom dual disc drive (350KB eh) incl FDC card NAS DOS dis s e 23.00 TAPES Blank C12 Tapes 6 minside) 1616 50 40.50 14.00 SU SUPAVALUE RING FOR OUR PRICES FREE SECURICOR DELIVERY 88 COMPUTER & VIDEO GAMES "


"The best enhancement yet for the ZX enthusiast |for just ! sinclair Sinclair GIM Inside the What is the best way to guarantee that you never become bored with your Sinclair computer? you make the right choice. There will be exclusive prerelease snippets on products which are about to hit the market. Our aim is to make Sinclair User invaluable and we will chronicle applications which are of special interest. For example, in the first issue we will look at business applications and we visit a school where the pupils are having the time of their lives using their Sinclairs. Each month we will carry eight pages of programs. Another must for every user is our first-rate helpline service. And we intend to carry as much information as possible about clubs. Last but not least let us say that the best way you can guarantee you like the magazine is by participating yourself. Don't forget to ask us your queries; send in your programs for which we will pay  if we publish and be sure to tell us if you are using your ZX 81 in a special way. Send in your club news and tell us of any interesting people out there in userland. And just in case you need further convincing, look at the editorial plans for the first six issues. Can you continue to get the most out of your ZX without reading the Sinclair User? So why not fill in the subscription order form today? Editorial Plans April August Hardware overview The Sinclair printer Software overview and its alteratives Chess programs The Sinclair 16K RAM September dissected Enhancements for the enthusiast Adventure games programs leg. colour, sound, June high resolution, speech) Business software Disks a look into the for the 2X81 future Graphics software July The ZX81 memory map analysed Debugging programs May The answer is to subscribe to Sinclair User ... written specifically for owners of ZX 80's and ZX 81's. Sinclair User is the latest monthly from ECC Publications pioneers of Practical Computing, WHICH COMPUTER?, and Computer & Video Games. Whether you bought your system yesterday or are an old hand, you are probably an enthusiast for your machine. And your biggest problem is likely to be obtaining all the information to satisfy your interest. We promise that Sinclair User will be devoted entirely to quenching your thirst for information. Issue one is Published on 1 April and is an absolute must for Sinclair devotees. So make sure you guarantee that you get your copy by taking out a subscription now. As the name suggests, the content will be geared specifically to helping the user. There will be pages of information on available hardware and software. Our expert writers will analyse established products to help Send to: ECC Publications, 30 31 Islington Green, London, Ni. No. sinclair Subscription Order Form Date Overseas rates: Europe , Outside Europe  (Including air-mail postage) Cheques should be made payable to ECC Publications Signed Please charge my credit card. I wish to start a subscription to Sinclair User. I understand that I may cancel my subscription at any time and you will refund the balance. D I enclose a cheque for  for 12 issues (UK only including postage) Card Name Name Address COMPUTER & VIDEO GAMES 89 "


"Tiny WHY COME TO US BEST VALUE FOR MONEY ALL ITEMS FULLY TESTED WIDE RANGE AVAILABLE INSURED GUARANTEES wo noon KEYBOARD OUR 'EXPERTISE? CAN HELP YOU OR RND MZ-80K (48K)  personal computer Start with BASIC on the Commodore VIC 20 Also PC1211 Pocket computer, MZ-80B & IBM Personal Computers, EPSON, SEIKOSHA and OKI printers, ALL AT SIMILAR LON PRICES. Programs & Packages of all kinds 2.9.:Asteroids, Space Invaders, Simon, Music Composer, Cribbage, PASCAL, Road Runner, Mother Ship, etc. by Don Monro Illustrated by Bill Tidy CALL US NOW 01-643 4290 Most Credit Cards Taken (At last) the real computer book for the VIC 20, the real computer that real people can afford and use. Croydon Micros .80 (inc. p&p). Send cheque or postal order to The Tiny Publishing Company Ltd., PO Box 120, Haywards Heath, West Sussex, RH16 3ST. Please allow 28 days for delivery. 202, Stanley Park Road, Carshalton, Surrey. SMS 3JP (Prices exclude VAT & delivery) (CV1) TECHNOMATIC MAJOR ATOM DEALER ATOM: Basic 8K + 2K kit  built  expanded 12K + 12K + via  (P+P .50/unit) Power supply 1.8A 8V  3 A 5V REGULATED .00. P+P .50 HARDWARE SOFTWARE/FIRMWARE 1K Ram (2 x 2114 low power)  F.P. ROM  Toolbox-ROM: Many new exciting commands incl. Buffers: 74LS244 .70, DP8304 .50, BILS95 .90 uprating cassette read/write level to 1200 baud & Via 6522 .00. visual indication whilst loading. Price incl. inst. manCONNECTORS ual .50. BUS: Plug , skt , PRINTER: Plug , skt  VDU: ATOMSOFT Plug .90, skt .90. Centronix Type 37 way .50. Games Pack 1-10, Maths Pack 1-2, Soft VDU, Chess, MEMORY EXPANSION Desk Diary, Fourth Data Base etc. .00 ea. Word 8K SRAM + up to 16K eprom or 16k SRAM can be Processor ROM + manual .00 populated as you progress. PCB: .50 (Incl. Interfac 747 Fit. Simulator, Galaxian, Chess, Invaders .00 ea. ing Data) Fruit Machine, Break Out, Disassembler UFO Bomber, 64K Dynamic RAM card (expandable to 128K). Fits Pinball .50 ea, inside the case. Std 1.8A PSU adequate. Built .00 BOOKS (no VAT): P+P 75p. \"Getting Acquainted with your Atom\" .95. \"Atom ATOM colour encoder card .00. Magic\" .95. \"Atom Business\" .95. P+P/book 70p. WATCH FOR DETAILS ON ATOM VISION TECHNOMATIC LTD All prices are exclusive 1) of P+P & VAT Add 40p P+P & 15% VAT Unless specified otherwise Send SAE for full details. Mail orders to: 17 BURNLEY ROAD, LONDON NW10 1ED Tel: 01-452 1500/450 6597 Shops: 15 BURNLEY ROAD, LONDON NW10 1ED 305 EDGWARE ROAD, LONDON, W2 Tel: 01-723 0233 Barclay & Access cards accepted For fast delivery phone us (min. order ) 90 COMPUTER & VIDEO GAMES "


"RSONAL COL 303 GENIE I ge nd vay nan, ian, ese, age. LON LONELY Genie I Microcom intel vated puter, early eighties, with large peripheral family but currently ATTI unattached, would like to meet wish may interesting, attractively packmari aged software, Genie or Tandy specification, for programming, SO problem solving, entertainment and long-lasting tion friendship. Reply in confihum dence. Box No RS232. MAL 5. Se met (ml nt DIY or a Vay, ingenious but lonely! to 10p wai wis ANSWERING MACHINES fice certified Expansion Box, Buying your first Genie I microcomputer is just the start of a long and enthralling adventure, for it won't be long before you will want to expand your system with some of the wide range of peripherals which make up the complete Genie System. Firstly there is the The supreme advantage of the Genie I system is its compatibility with the TRS 80, which means that literally 1000's of pre-recorded programs are which immediately expands your already available, just waiting to be plugged into Genie's capacity to 32K RAM, and your Genie! up to 48K RAM ifrequired. It can The recent improvements in the Genie system, be connected to 4 disk drives, a including Extended Basic, sound unit and printer, RS232 interface or S100 cards. machine language monitor, make it the ideal system for the committed hobbyist, and an Then there is the excellent and easy-to-use educational tool. Printer, a compact unit with 80 column, 5 x 7 matrix print-out, which connects SPECIAL TECHNICAL GENIE to your Genie through the HOT-LINE ON 0629 4995 Expander, or via the Parallel Printer Interface. for all your technical advice and service back-up on any aspect of the Genie system direct from the experts! The Disk Drive Please send me FREE, 16 page colour brochure on the Genie Computer System. I enclose 25p postage. Name gives you greater storage capacity and full random access file handling, with the option of double-density through a special adapter. New Dual Disk Drive now available! Finally, there is Genie's very own Address Telephone CVG-82 12\" Monitor a must if you want to let the rest of the family watch their T.V. in peace! Available in B & W or green tube. Chesterfield Road, Matlock, Derbyshire DE4 5LE. Telephone: 0629 4995. Telex: 377482 Lowlec G. "


"Adventure into ATARI With Maplin... Through a thousand galaxies of time and space... From across the ravaged oceans... From dungeons of fantasies... After battles with enchanted dragons... Come the fabulous Atari computers... the ultimate creative game computer! Command a space-ship through the dangers of deep Spanish, Italian and Touch-typing. Or just use the Atari to space where alien contact is inevitable or take your create your own programs-the Atari makes it so easy to chances as you adventure through forbidden lands in generate really incredible graphics. It's all part of the search of secret treasures or play Space Invaders, magic of Atari. Asteroids, Missile Command, Super Break-out, Shooting When you decide to buy Atarl, you're choosing one of the Gallery, Jawbreaker etc, etc, just like they are in the most advanced personal computers there is. arcades, but in the comfort of your own home. When you decide to buy Atari from Maplin, you've made Or discover the superb Atari teach-yourself programs that the best choice of all... because Maplin support will help you learn: Programming, French, German, Atari...totally! Write or phone for your Maplin/Atari information pack NOW! MiaPLIN Demonstrations at our shops NOW See Atari at 284 London Road, Westcliff-on-Sea, Essex. Tel: (0702) 554000 and at 159-161 King Street, Hammersmith, W6 Tel: 01-748 0926 Maplin Electronic Supplies Ltd P.O.Box 3, Rayleigh, Essex. Tel: Southend (0702) 552911/554155 "

