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Interact Network Newsletter

1. Hello Interacwophiles OF ABEE i le E T ob fy x Pat ri 4 t 4 ia We f a I we spend a lot of time in the lase couple of months trying no decide what form this newslereer should take the direczions the philosophy the goals Sure you say Micro Video is publishing ir so it s simple z Sell more Interact stuff Micro Video is of course running a business that s partly based on Int ract software and accessories Bact it s noe chat crass Of course one objec tive isto inform you of what s available to provide information on what the soRwete does and what the books contoin s0 you am make inteiticent selections You ean buy what fills your needs and detires and ave it perform to your expectations If yow re happy wiiitthe software you selecte you ll buy more Ard thar benefits everyone Rut luane this newsletter robe much more chan fesc an expended catalog We knew that most of you baught your compuzers for moe than pest playing games We wont to help you use and enjoy your computer to its fullest potenrial The folks a Micro Video realised that it s hard to be objective when you own the store so they asked me to write and edit the newsletter for them a cery wise move i oun an Interact program itin BASIC and machine language and hase some uniting expenenee also have a full time job My computer ismy hobby am nor an emplovee of Micro Video l manIntevect owner and Inc
2. i Li all 4 E p a ey aa ichi i i a m 4 om a E pede T bie s h i im m iba N gt ee a p a k ee it 1 SE E CE TES EE e f a bh H em eS ee i eee Ee Dear Micro Video Thank wuu fim lhe prompt reply con cerni neg Mazes and Monsters sent my old tape to You on Monday and received a new one on Friday Thats service The new ape is much better and I snm thoroughly enjoving it John Suut has really made a great game The veason I am witing if because would Jike te know f vou are going to hive game tapes in the fieture for the 32K Tam thinking about the upgrade but atm not into programming I l probably be sending for the new typing keys seon for sure enjoved the RAM Pages and am glad vau have this newsletter must compliment whoever types for Micre Viden Jt is a real pleasure to weed the instractiuns ete chat I receive und see everything spelled courreeiy and the formal is sat up so nice am a secretary nd appreciate this Sincerely Roberta Hiutz Watsontusen PA Dear Rebvrtia We ve considered putting out u 32K udlventure game Most outers re stili limited to IGN though and thote who ve upgraded their machines are generalis most tnfereshiicl m progerenuniag ar btesi ness vpplications rether ilun pemes We do hau plans for more 32K software betel cen probably ho bustacss oricuted Sue Denim De
3. i t e ao Pe Fe ee a Ty i a i a m n s IPT E e F z i m ey I no y m IF aie a a 2 o a u Pa d mai n L 7 a s i I 1 mo mm E a ti A aes z m i a 7 l a ares pT F C p 4 C s X a a a Tan a a Pai Li m Li a m n ri iT 1 s T 4 B i iJ aon ol Doctor Symptom After pressing L the tape turns but hear no loading sounds and the program doesn t load in Diagnosis Broken or loose wire on tape read head er read write con tacts Rx This preblem was brought to vur attention by David Stephen of Moatreal Quebec He reports that he s had the problem numerwuus times over the past year or se The cause is generally a broken or loase wire in one of two places the tape drive read head or the read write contacts described and illus trated in my last article jf the wire contact at the read head iS broken the head cant pick up sig nals frum the tape and nu loading will be achieved To correct this de lect remove the cassette drive from the upper main housing and the plastic cover from the drive The read I d like te talk lo you for a moment about my new book The Computer Dector and give you my prulessiunal advice Buy it F give you three gwd reasens why vou should First of all vou can save money on compuler repairs with my book A number of units come in for repair that have relatively minor problems that could usually have
4. 1 C W B W 2 920 CLS 525 LPRINT L 77 930 CLOAO X N X 0 545 IFN OGOTO100 x Asien jhe 580 Fa ABS A CVC W AE 565 FACET ENF F 568 A INT M MIFE 570 IFA lt i S80 se vi M 1 00 A INT A 1 ya 601 IFL gt 0THENPLOTI L A 602 NEXT 610 FORI 1TON LPRINTCHRS C X I NEXI 620 LPRINTCHRS 33 630 FORI lt 1TON LPRINTCHRS O X NEXI 640 EPRINT 1 G0T053 Wirth a Look Terry L Wirth of Phoenix AZ rigged a way to use his Interact to turn on and off just about any smail electrical device He reports that he discovered the idea while trying to key his amateur radio transmitter with Morse code using the computer as a keyboard He simply put a rela across the tape drive motor With the tape deck turned of any commands such as POKE operate the relay instead of the motor and give an output He uses timing loops to vary the signal lengths Reposition Proposition Another modificationTerry Wirth devised solves the problem of having to type REWIND every time you want to reposition your tape He installed a miniature toggle switch and aounted it just to the left of the write button He says it does not affect the autematiic operation of the computer when it controls the tape deck By referring to page 6 of the Interacts schematics he found amp 1 which is a transistor switch that t rns the tape motor off and on and completes the motor circuit to ground He put his switch across the transistor swi
5. Dear Micro Vidco If RAM Pages werc more substance and less style it would be worth half the price So cute So slick Henry A Morgan gee TA Dear Micro Video I have enjoyed al of the past articles in RAM pages for one would ike to see many technical articles on the internal operation of the Interact This I thmk would help all owners to diagnose some pioblems that they may encou ter for one have decn vers lucky in repairin mine but it teok me quite a white before solved it Now for the first time in two years Lenjoy using it Angelo Ippolito Bloomfield NJ Dear Micro Vidco What is the overlay for Packralt and hew does it work Wii you be coming out with a game similar to Donkey K ong Is your game Caterpillar like Trailblazers I enjoy Jungle Run very much and my whole family enjyys playing on the cem puter Scett M Buigener Phoenix AZ Bear Scat The Packrat overiay loods in afer Pack rat and offers you 20 eren game beards on which to play The new game buard yeu select overwrites the existing one and you can change buaids as oftest us yuu like Our dumping Jack program ts similar in nature to Donkey Kong Cater pillar hus similarities to Trailblazers but it is not at all the same game The object is to gobble up the other player rether ther bwa him in and personaliv f thinkiis much more ttn to play than Trailblazers RAM Pages Subscriber Survey Te help us ke2p adreas
6. trp i i hi D ra Feedback continued from page i7 leoked it in debugging the ROM w hice incidentally was produced in 1977 Dear Micro Video I think you should know that Kathe Spraklen s book and your AL and Bombs Away explanations ave horribie ways to learn Assembly pean The writers assume ieo much and explain teo little One pretty good beck that found is for 2 80 programming only but when ceupled with the above two can lead to some sert of rapid success It s called Machine and Assembly Language Pro gramming by David C Alexander Pub lisher Tab Books Inc Blue Ridge Summit PA 17214 Maybe when I learn the lang age well Jil write a really ged book for you 999 Dear Your note reached me with only a scrawled initial os a signature su I couldn t identify you for vur reeders Care lo ident yourself Thanks for suggesting another buuvk owners might find useful in learning as sembly language Dear Micro Video No haven t decided not to subscribe and no it didn t slip my mind either Nor do have a friend who has subscribed nearly all my computer friends have a _ z a r am a um LETN an pe is eee os z x k a Sere a eu i oOo a z a m ppn z 5 s 7 gee e E E 7 A 2 ygres wollen ge a oe ee ee aA ee p me ee a ee ai i a n rii T the or el ies DSE me E L
7. ACTION G iting games can be as much fun 25 playing them As you learn more about programming most of you wl l sackle an action ot atcadestyle game Maybe you already have In programming an action game in BASIC one fact readily becomes obv tous wonderful Microsoh BASIC with iss blinding calculation speed is s000000 slo e0 ow Many people feel the only solution lies in machine language Well yes machine language is many times faster than BASIC But machine language is harder to learn than BASIC and ic rakes a long time to write a machine language pame a good 8K game can aake 2 3 months cf everiags If you want to learn machine or assesobly Language by al means do se Meanwhile dont dixpunt BASIC enzsely Good ac don es are Vet ible f you give cine koust to jR r peen TN aldi program Micro Video sells quite a few BASIC games some of which can tightly be considered action games Artillery Command Bowling Drivers Sear and Dr Doom are examples Dr mia pretty fair representation of the arcade motorcycle jump Phaps you ve dropped a Gumeerortwo on is ee fol ing a few r ules designing your game carefully and using speed aechniques you can write your Own vety decent action game in BASIC I When possible design your game with action off contol When lt i dificult movement star amp take contol away from the pam by design In Artillery Com mand for example che player entezs the angie and
8. Finally the mest important ques tions you can ask yourself about your program Would I spend my hard earned dollars buying this program And if I did would I be disap pointed when I gotit Your answers to these questions alone will give you a pretty good in dication of how interested other users will be Before you send a game or pro gram in for review we recommend that you play test it extensively At present Micro Video employs two programmers full time with a third to be added in the near future John Stout is our programming manager and although he s anly been on board since March 1982 he s had a hand in almost every new piece of software in our last two Jokan Staut Tort Matuleich catalogs His latest masterpiece is Mazes and Monsters an exciting three dimensional graphic adven ture A music macstro turned pro rammer the holds B A and M A egrees in Music Composition and Conducting John has become in strumental in our program de velopment He not only coordinates our programmin f activities but also has responsibility for reviewing software submitted from outside sources John spends a large part of his time outside Micro Video arranging Get as many of your friends and re latives as you can to try it out Watch to see how long the game holds their interest Ask their opin ions and impressions and look to them for suggestions on improving it If you get consistentl
9. Modification Instructions Remove the top of the main hous ing then take off the top metal plate of the main electronic subassembly housing You ll need to detach the metal connector plate too sliding it through the hole in the larger plate The RF canister is located in the upper right section of the main elec tronics board It has a metal cover that may be soldered in place on both ends Remove this cover to expose the RF circuitry and you re ready to start on the modification itself The first step in the procedure is to take several components out of the RF section Using your soldering iron needlenose pliers and Xacto knife remove the following paris which are identified in the photo of the RF can R82 2 7 Kehm resistor R87 1 5 Kohm resistor LE 56 microhwary coil L5 4 7 microhenry coil Cig 27 pid dise capaciter When you ve campleted this pa t of the precess start recenstruction and replacement by installing two jum Audio Cable Connection Pin 11 LM1889 RF Chip P T F om E a by is i a i p i i a ll MV 209 Pin 8 R82 Pin 9 pers One replaces L6 the 5 6 mh coil solder it to the foil pads at either end ofthe L6 area The other jumper replaces coil L5 and capacitor C16 Solder it between the foil pad on the lett side of L5 and the foil pad on the rightof C16 Both jumper connectens are identified on the photo and schematic Next solder the posi
10. Now we re human and like all members of the species we do make mistakes now and then But in each of these cases the Interact s iden tits crrsis was the root of the pro lem People were simply not sure who they were dealing or not deal ing with Se ence and for all let s set the re cord straight We ll try te shew you as succinctly ns passible that al though the companies did sometimes work in cooperation with each other each has tts own separato identity mode of operation and philosophies Here s who s who Interact Electronics This Ann Arbor based company was the originator of your computer Their stall completed the design and de velopment phases then contracted fanuTronics to do the finat assem bly and production Interact Elec tronics was largely unsuccessful in marketing their preduct and went out of business in December 1978 They sold the bulk ef machines re ManuTronics MICRO Protecto Enterprizes SS a maining in their inventory to two CE CHE and Micro Videe ManutTronics The original as sembler of the Interact computer this firm was Ieft holding finished computers and parts to build several thousand more when Interact Elec tronics closed their doors To recoup their losses ManuTronics continued producing the computer which was then distributed as the Interact Model R They sold some machines directly but their primary outlet was Protecto Ente
11. W POKE24656 0 20 POKE 4G 9 95 POKE24678 0 POKE24677 195 30 FORM 243201024380 40 REAQP FOKEM P 50 NEXT 60 DATA214 32 245 14 2 205 46 6 2847 70 DAIA202 208 96 259 19 202 246 96 254 10 80 DAIA202 0 97 2548 202 125 96 241 79 30 DATA213 42 6 76 62 68 189 197 220 236 100 O47A96 193 42 6 76 238 208 91 5 235 110 DATA346 76 14 3 205 46 6209 228 201 Great Restorations Revisited In the last issue of RAM Pages Great Reslorutions p 12 we de tailed how you can control BASIC s data pointer with the RESTORE command and a line number This al lows you to enter a data list at a cer tain point bypassing vatues you don t want to use However Manuel Uson of Caracas Venezuela res ommends caution when using EZEDiIT with such As ger He re ports that the RESEQUENCE com mand doesnt recognize the line number on RESTORE It therefore does not change the referenced line number to reflect the new pesition when it renumbers the program lines you ll have to change line re ferences in those lines with SUBSTI TUTE Gracias Sr Uson for passing along this tidbit Byte Bomb In Small Bytes Spring 82 one contest entry was a pr ram that computes a checksum on Microsoft 8K BASIC to check for camag from improper loading or errant POK Es Richard Thwing of Columbus NC says the program well alwavs re port BASIC BOM BED because the value of address 32767 under Mic rosoft 8K BASIC is 100236E 06 wh
12. much more The Interact was after all a dead product We never anticipated that you d grow from a tiny group of users to an active community over 7 000 sirung and that voud want more suflware more accessorics more of everything for vour machi nes As you ve grown so have we One by one in rekponse to Your Input un what vou needed and wanted we ve pushed the Interact pushed it far beyond what tts critics said it could be You wanted to be able to pro gram in machine Innguage so we gave vou the Micro Video A lonitor We ve Moved and more recently assembly lan guage capability with Assemblex Editex You asked for better BASIC decumentation so we got out our pens and out came Basicalirv Speaking Your returned surveys told us that vou wanted more men orv so we developed the 32K expan sion Yuwve niso indicated strong Interest i a nass storage device To add a Noppy disk to the Interact as it is currently configured would re quire extensive and expensive hardware modifications However weve been able to interface to the Exatron Suringy Sponge a reason able alternative both operat senally and economically More action games vou cried Have you checked oul the three pages of action games in our recent catalog And as Ad venture gamer became the rage we added the Troll Hole Mysterious Mansion and Dragon s Dungeon RAM Puses hope speaks for itself That s a brief summary of where
13. s Granite Falls NC three dimensional pletter pregram that we decided wed mnde a mistake in not printing it in the first place Here it is 50 Phe 3 141592656 60 X 2 6V 77 70 COLOR4 3 3 7 100 OEF FN 2 X SIN X SINY 101 RHe75 Plo l3 THe 4 0 400 102 YE 30 XE 30 103 NX XXe NY 5 XY 5 108 US 110 PRINT 3 0 PLOTTER PR ANT 115 PRINT BY CHUCK YOUNT PRINT 120 PRINT TO CHANGE FUNC TION BUT FRO GRAM AND DEF FN Z 130 PRAT UE LINE L00 PRINT 140 PRINT OO YOU WSH TO CMANGE THE DE FAULT VARIARE VAUJEST 14SAS WSIR 150 FAS N THEN420 160CLS 170 PRINT Contest continued ron page 13 ELECTRONIC SATURN 10 CLS COLORO 1 2 4 C oer SVTOZESTEP i FORT 55F02 26STEP 0 20 AOTSH R S OKT 2 98 R COS T A CNEXT C C L IPDS THE NC al 22 t K1 CHLFORTeOT06 28STEP 03 FORR 1027 PLOTS64 R SIN T 384 R COMN C 26 NEXT C C H C gt ZTHENT I 28 NEXT C i FORR StOZESTEP LAORT 2 27105 73S TEP 03 Soh Fett Programmer Deaibom Heights M 220 PROWSUETESTED WALURS Mi DS CHAE AS VOU WH 2 30PRINT 240 1NPUT MIN X05 A0 250 INPI AT MAX X 5 XX 260 Sits FHXTHERPRINTARAX lt NaN 01024 270 INPUT MIN Y 5 NY 280 INPIFT MAX Y 5 XY 290 ero IHENPRINT MiX lt MJN GOTO 300 INPUT X EVALUATIONS 15 XE 310 INPUT Y EVALUATIONS 15 VE 320 XE ABS INT XED YE x ABS INT YEL 330 INPUT THETA ANGLE 4 0H 340 INPUT PHI ANGLE 1 3 PH 350 INPI
14. they need to be told when to paginate and how much lf your printer prints continuously you may want to add this extension to Microtext This modification puts a line counter variable LC in the program that forces pagina tion after 60 lines To implement it you ll have to add four new lines of code 1490 1510 and change five exist ing lines 720 TB 0 KS S GOSUB 1500 IF SK 1 THENGOSUB 1490 770 FOR t 1 TO C GOSVB 1t490 NEXT GOTO 600 895 IN 0 GOSUB 1490 GOTO 600 1030 TB I KS IS GOSUB 1500 iF SK 1 THEN GOSUB 1499 1370 TB IN KS LS GOSUB 1500 LS IF SK 1 THEN GOSUB 1490 1490 TB 0 KS 1500 LO LO i iF LC lt 61 GOTO 1510 1505 LC 1 FOR T 1 TO 6 LPRINT NEXT 1510 LPRINT TAB TB KS RETURN What if you want to print only 30 lines before invok ing automatic pagination and you want to skip 10 lines corrteersaced or page 5 t3 Help When I bought my computer from Protecto En terprizes about a year ago I re ceived a Music Maestro tape butE didn t get the plastic overlay the documentation describes I called and asked about getting one from you but was told they weren t in stock It s pretty hard te use the program without the overlay Is there any chance of my getting one or am I stuck with a useless pregram You re in luck We were out of o the overlays but we ve recently had more made They re now back in stock and you can purchase one for 0 00 Help I sent my computer in e to you for r
15. you better make sure at is good reliable accurate Information ur some u et group will drive you out of business ask yuu wouldve u slightly less pre m p T e Soe ae as TETs m e x ee n Iae D i aaa a 9 ad D oe pu he TT 8 Lod boa it ee hl A r n xpi wee we eg te O o aad m a o ee A gates DEELGE ielat A With Par as T 5 eo 1 ea ti r mT i 5 4 F aly i iy a a F T P i E F i re bf eye ei em eel aeg me Pee i eib i ee F ee d ial F I E E I i i F Sr ee Mantini era ae i eee Lies ft i f A 7 on o os a i s ry a ee fessional orig wary at a more reason able cost benefit beth Micro Video and your customers Stncerely a subscriber because I need you R Rex Reid Housten TX Flex about it felks Do you agree Fill in the survey form and help us tailor RAM Pages to your needs Dear Mucivo Video am not sure whether thereis atypoor you changed Zip Code number but in the Publication box an page 2 and on the Sub ecriplien form page 18 the Zip Code ts Slated ns 48103 and the other places as 48167 Which is right Carl R Schriver DuBois PA Dear Cail Both are ft has to do with pestal regu lations Our street address and pos office ber are actually in two different Zip code areas The Zip code used dePends un which line appars immediately above the City line tn the address Our POB is de street address is 48203 Crazy uhi
16. 32K expansion Exatron mass storage device and professional keyboard have taken precedence in develop ment You can be sure that when it ts offered ROM resident BASIC will be compatible with our other hardware upgrades so you need not delay ex panding your computer to 32K Q8 Are you going to offer the 32K memory expansion as a kit In an immediate sense the answer is no The upgrade is far more intri cate than the RS23 installation ene a which many users had problems in sialling We ve found that a variety of things can go wrong in the installation process the added hardware tends to stress the weak Points in any machine chips resistors even the microprocessor Our technicians have the training and diagnostic cquipment necessary to pin point and correct these problems quickly We do however hope to ect the proce dures relined to the point that we will be able to offer the expansion in kit form Q9 Cm thinking about buying a printer Is there any one that you par ticalarly rec ommend We are very much impressed with the Epson MX 80 prntcr and have recently begun carrying it and the MX I0U Information on the Epson and connecting it to your computer ts now being shipped with all RS232 ports shipped If you want ttis infor mation send usu S A S E or request that it be included with your next order QIQ Can I acvess a timesharing sys tem and run my prinicr at the same time
17. 605 IF LEFTS IS 2 2 GOTO 690 610 IF IS lt gt ENOTEXT GOTO 840 705 if C Z GOTO 910 The Beld Approach If you have an EPSON MX 80 printer and you d like Microtext to be able to take ad vantage of its emphasized text capabilities add the fol lowing line to the program This gives you a E directive that you can use to put bold extended headings on material you produce 662 IF CS E THEN LPRINT CHRS 14 GOTO 600 The following set of data lines show how these two fea tures can be used When the data statements are exe cuted by Microtext it pauses at line 40 to request keyboard input ZAGENT NAME Ifyou run the pro gram with these data statements whatever you type in response to the AGENT NAME screen prompt will be embedded in the processed output as illustrated in our sample above 10 DATA E 20 DATA CONFIDENTIAL 30 DATA L 40 DATA Your mission 7ZAGENT NAME 50 DATA should you decide to accept it is to 60 DATA destroy the nuclear test facility 62 DATA at Zahidan Iran 70 DATA L 75 DATA The accompanying inteltigence photos show 60 DATA ENOTEXT Page After Page You may also find it useful to be able to control the number of lines printed per page and the number of linefeeds between pages Some printers are smart They know that they re supposed to skip several lines after printing a certain number of lines usually 60 However some printers are dumb
18. INT RND 1 3 PLOTB C 0 N EXTJ From Jay Gardella in Bonita Califoinie a Level li one finer that gives a colarfidl Interact greeting 10 COLORA00 8 PRINT HELLO A INT RND 1 7 B INRRNDX1 6y GOTO10 E C Herezlee of Dearbom Michigan POKEd a sideways scroll im his Leva If program foo a seappered effect that s rather interesting POKE 24888 32 eo return ao norma scrolling when you re done running this program 1 CLS COLOR 1 3 4 POKE24888 1 Y 12 A MICRO 8 VIDEO S 46 GOTO3 2 FORI 1T012 OUTPUTCS 70 Y C TONES 9 FORP 1TOS NEXT Y Y 6 NEXTI RETURN 3 C 3 C A GOSUB2 C 1 Y 14 C B GOSUB2 COLORG 1 3 5 D INSTR 1 GOTO1 Tenzem old Todd Trumbull submitted chis Microsofe 8K Small Bytes Take cover 10 CLS COLOR 2 4 4 20 OUTPUTRED ALERT 37 59 2 SOUND5 398 30 COLOR1 0 0 7 GOTO10 Jim Gindin of Ann Arbor Michigan sent in this Microsoft 8K program wich moves a game paddle on che screen and tests for a kit on a angel In only 3 lines 1 A INT RND 1 55 11 3CLS PLOTSO A 3 2 2 DEFFNAD ge 1 2 PLOT20 8 0 2 5 C POT O B FNA X PLOT20 8 2 2 5 E E 1 1FFIRE 0 1THEN2 3 AS STAS E OUTPUT T A 38 50 1 1FA B TORA B 2THENOUTPUT HIT 47 60 1 From Jeff Thompson in W Melbourne Florida came this cheerftd one line Level H program He calls it hts Bird Sanctuary 5 SOUNDO 24844 FORX 3T021 NEXT SOUND7 4096 FORS 3TORN D 1 98 NEXT GOTOS5 Another budding ge
19. Press F FWD then any kev gt Press tor number of program to be stored then re move the multi program tape insert the first program to be transferred und then press READ 3 Reinsert multi tape Press READ and WRITE and type CSAVE Your progam name 7 Repeat steps 2 6 for each program to he stored For denser packing of programs on the multi tape Jarvl determines the byte value of cach program he avants to store by using the PRINT FRE command Te subtracts this number frem the total available mem ory multiplies that number by 235 und adds 390 for the eader tone and 100 for the counter This calculatien de ermines how much room on tape is to be allecated fer a rogram Pn To calculate each program s tape position te uses 50 PVt 504 PV1 PV2 and changes the values associated with G line 2300 to reflect them It s a let ef vork te get the multi program tape built but once done he system provides fast access to vour Programs Congraphulations Michael Stolvicki of Bloomfield Hills MI came up with a scheme to develop a graphics dispiay for his gradua tion party First he loaded Compute A Color created a pikture and saved it on tape Second he loaded in the Micro Video Monitor and set a partial 63 line window Using the L command he loaded the tape created by Compute a Coler Then he moved the iirst 65 lines of the screen to the end of BASIC text area 570011 and wrete the moved mem
20. Remember that pon must type NEW after loading ASIC to clear out the memory for new program storage a 7 On the inside Programming For Fun or Profit Of course you like all the games you can play on your Interact But the real reason you bought a compu ter instead of an Atari or other video frame is that it is programmable ou re not just stuck playing games youre thinking and learning and in creasing your awareness about a field that is going to be an important part of all our lives in the future There are many budding pro g ammers in the Interact user com munity and the programming staff here at Micro Video gets a lot of calls In addition to specific pro ramming queries we are also requently asked two general ques tions I What kind of software do you have for my programming interests and skills and 2 I have a program I think you might be interested in putting in your catalog How do go about submitting it Programming Your Computer There are a number of ways to program the Interact We use many of the same tools available to you in creating our software as well as some you probably don t have We produce all our program master tapes using an Intel 8080 develop ment machine with an JCE 80 inter face that emulates the Interact s operation This system has tremend ous advantages over the Interact in memory size 64K and program storage dual floppy disk Now an Intel developmen
21. The video RAM is mapped in bytes from 4000H to 499FH Graphically each byte represents four pixels and each pixel is control led by a two bit segment of the byte The two bits represent a number 0 3 which indicates the color that pixel is to be In our examples in this article we ll assume a color set selection and represent the colors as follows eur O black color t wilor 2 green iig color 3 white E if you need further information about manipulating the color set in machine language see the Guide to ROM Subreutines 4 Also remember that a byte value is det ermined by the relative on off status of each of its eight bits There fore a byte containing all four colors in the color set might look like this bit value N 8 4 2 TE 4 al ajjijijojojij o orl colore colocd coor O 4 ZeloT 0 0 2 022 i 72H Notice that the Interact reverses the bit pattern when it displays the byte on the screen _ It s important to keep this in mind when developing your pictures or you may end up with some very strange looking images Pictures then are stored byte by byte in tables that are used by the Move routine Let s say we want the following image to appear on the screen WY WY UW WU YY Yj Yh al banl Bann Y YY A T T E E a MEINE d You can see that we ve got a white face with a black mouth green eyes and red hair You can also see that the p
22. command is called SET format SET X Y Because the TRS 80 has no color capability only the two screen coordinates arc needed To erase a plot they use RESET X Y We can easily emulate therr plotting commands by using PLOT X Y color To erase the screen of course just replot the coordinates in the background color I ve found that if haven t seen the actual screen in a TRS 80 program if often helps just to replace the SET and RESET com mands with our PLOT command Even though the result will be upside down and won t fill the screen it s then easy lo see what the picture ts supposed to look like Just stand on your head Seriously you can then refigure the coordinates to fip the picture add color and stretch the gtaphics to fit the screen Remember also to watch for commands that con trol movement you ll have to re configure those operations to fil the stretched picture on our screen loo continued on page I8 a aa aia be Saa eia a This issues On the inside col umn features Dallas Maddox Micro Video s new Afanager of Customer Services She s compiled a fist of the 20 guestions Shes asked most fre quently along with the answers to each Sie hopes shell never tare to answer ihem again QI Js all the software and hardware listed in the catalug available The software is generally always available because we produce it right here at Micro Video Sometimes there is a delay in releas
23. eratien all your game displays are best seen when your computer has a geod eutleok en processing For ex ample in ene of our newest games WING IT the vertical red lines that form the rafts lese their width and redness if your computer is in bad humor Also the vertical striping on the semi truck becomes faint However when yeur cemputer is happy the raft legs will appear a rich red and the stripes en the truck which are really alternating red and green vertical lines look like high resolution white lines You ll miss that marvelous eptical illusion if your computer is feeling depressed if yeu try this test and don t notice any dijlerence in the screen s ap pearance then yeur computer and IV probably get aleng famously and bad screen display isn t likely tobea problem for you If you de notice changes you may want to pay closer attention when you power up your system to get optimum visual per formance ortunately your cempu ter s outlook is easily improved just turn the power off and en until the screen display indicates a goed disposition Think of it your computer may never have an elf day again ay i i Ph a ip Hi E PERE bo Te a Cree roe a Ta ARCEA Ea iy E r ga ag eens fe Sa eh a i AR Tal rE ce AS AA rei INO e e Pan ies E ir Ei S elar a it Ta FE REEDIN AN ye ht wap i ea i pe Wace ee PEETI eda eee ts A A a TAN aei a i net en e ere a ie aa je
24. iu bply boards Ouming and using yout intecace is a positive expecieece bue for a moment ier me be negative The surveys expressed a lot of wants and wh le we wish co Alias many as possible some will just never be We are pretty much stuck with I6 character lines You cannot load capes from other brands of eomputcrs bue this is tet a situation unique ro che Interact You also can t load an Atati rape on a TRS amp a TRS80 tape onto an Apple an Apple tape onto a TI 99 4 ete No cross compiler is for hcoming COBOL and FORTRAN are out of che question ee COBOL is available for the Apple It re quires 48K sofacatd 2 dix drives and cests 750 Another rhing that came up in the surveys is people wanting free access te produces Micro Video lls Fhe 25232 port and che new memory expansion in volvcd a gzcat deal ef ungtncering pro Cotyping and manufacturing ceses Fhe designer and Micro Video expect a fair return on their work se ne building plans will be offered The same applies co che sofware I jusc recently finished a cCerncinned an page 2 eontmued frovt page machine language game that will be mat keted threugh Micro Video It took ovet two months of work in my evenings and weekends to complesee Wich our small market compare against TRS 80 s 400 000 users che bess expected retum is vety small lf you like the software it s wotth 15 dollars Thus is cheaper than software for most other mic
25. peared in the February 1982 issue of Creative Computing m Valuable Coupon 20 OFF YOUR NEXT ORDER OF 25 00 OR MORE of Mero Viden Software Documentation WSIS Peripheral Intectace ur SIK Memory Expanston LIMAT 1 COUPON PER ORDER HELP Your mailing label must appear on the reverse of this coupon COMPON MUST ACCOMPANY ORDER OFFER EXPIRES 8 33 82 Offer applies to dist price only No deien please Discount not applicable on computers Vurvax Type N Tulk Exaron Stingy Sporn ee p inters or shipping charges Offer void where taxed or prohibited by jaw Coprnght PAD Mient Vike Carp Need heip Ca 313 996 0626 Q I bo giu a USAM RS232 port in stead of the ane Micro Video sells Now tev tell me they cat install me meman expansion Am being piven the runaronuad just because I didet buy their port A No the UOM port is not compati ble with the memory expansion although Micro Video hoped that it would be There are at least two 12a sons for the incompatibility The first has to do with where the port resides in memory The U8 M pon is not prop erly addressed to be usable with the Micro Video Expansion or the RS 232 software it clobbers al memory above C0Q 0H The second reason is how the port is mounted internally The U80M port sits vertically front to back on the main PC board while the Micro Video portis mounted horizon tally side to
26. the second line specifies that values 00H and 18H are tobe 6 passed tothe D and E registers respectively You could producethissamesoundin BASICbytypingSOUND 3 24 MVI O 03H LXI D 0016H CALL SOUNOL RET You can change the parameters and call SOUNSL again to produce a different sound such as a laser This is equivalent to SOUND 0 264 MVI C GH LXI 0 0108H CALL SOUNDL RET Sometimes you ll need multiple calls to SOUNDL to create a desired sound effect The following example combines two sounds that taken individually would not provide usable sound effects However if you put them together in a routine separated by a short delay you ll get a sound that will ring your bell MVI C 0H LXI 0 2042H CALL SOUNOL LXI 8 0008H CALL DELAY ROM SUBROUTINE AT 07F6H MV C OH LXI 0 2CD2H CALL SOUNDL RET Other sound parameters when used in combination can produce other sound effects for use in programs such as a gunshot MVI C OIH LXI 0 0200H CALL SOUNDOL Lx B 0008 CALL DELAY ROM SUBROUTINE AT O7F6H MVI C 01H LXI 0 0203H CALL SOUNDL RET Want a sound to go along with an explosion on the screen Just modify the above gunshot routine slightly Change the value passed to the DE register pair on line 2 to 0202H and on line 7 to 0203H Experiment with SOUNDL Try combining parame ters and delays to see what you can come up with As with the SOUND command in BASIC not all paramet ers
27. the pee ranmrig and testing on another Interact in the shop Even though s mething may werk outside the car we can never be sure it witl work inside There ate lots of factors t c nsider such as the effects of road vibration In case you re interested Don is willing to sell his pride and joy Con sidering the amount of blood sweat and tears not to mention money he has put into the design and develop ment the price ts a steal 150 000 For a few extra bucks he ll even teach you how to drive it ay The Right Printer for You With the Interact s limitations in character display you probably have contemplated buying a printer If you ve shopped around you ve cer tainly noticed that there is a wide variety of printers available with an equally wide price range Trying to Pick tho righi printer can be perplex ing People huve asked us which printer is best suited far the Interact and there s really no definitive an swer We can however offer some guidelines to help make the selection plocess easier The printer investment is substan tial frequently more than the com puter itself Typicalty you can expect to spend 500 800 although there are exceptions both higher and lower The price shoutd only be one factor in your decision You well aiso want to ta e into consideration how you will use the printer what kinds of things you will want to pint The ansivers will influence your printer dec
28. 00 tora s___ jus Please ailaw 2 4 weeks for dehwvery Signature MARE Te ra a ee U S amp Canada only Other international orders add 6 00 shippingshandling Account Na Expires m a I master charge Phone Orders Welcome aaienia MICRO GY VIDEO 305 North First St P O Bux 7357 Ann Arbor MI 48107 1313 996 0626 MICRO g VIDEO Butk Rate ES Postage 305 North First St be oa P O Box 7357 Aan Arbor MI Ann Arbor MI 48107 313 996 0626 Do we have your correct name and address Are you receiving all your catalogs and mews letters from Micro Video Please check vour address label and tell us of we need to make any changes Submitting Your Software Now on to the second issue solfware submissions Some of our most popular games such as Hot Rocks were designed and developed outside Micro Video If you ve got a program you think we might want to include in our catalog we welcome you to send it in All software sent for evaluation should be sent to the attention of John Stout But before you send it in ask yourself a few questions about the program The answers to these questions will tell you a great deal about how market able it is Is the program a variant of something already available for the machine We re not interested in duplicating material we already have We d have very little interest in another Alien Invaders for ex ample This is
29. 10 CLS COLOR 1 7 0 4 20 PLOT 6 0 3 56 77 30 FOR X 0 T0112 40 C POINT X 35 50 PLOT X 35 1 6 PLOT X 35 C 7 ONEXT 80 GOTO 30 Hew can I move a zeken on the screen wttheur erasieg the a T Pm aftaiid don t have a useful answer for you BASIC 10 CLS COLORQO 1 7 4 FORY 70TO38STEP 6 PLOT10 Y 1 74 3 PLOT10 Y 3 2 74 3 20 NEXT PLOT 0 3 1 74 3 PLO7T10 52 3 32 21 FORX 12T OS9STEP3 30 FORY 71TOS STEP 4 PLOTX Y 2 OUTPUT AMERICA 25 30 2 NEXT NEAT RUN Latry Jensen of Annandale Virginia proves that you can do useful eperations in just 3 lines His bro gram entitled Pocket 7 Caladator computes the sum difference product ot ratio of any two numbers 1 PRINTF A SANPUTA PRINT fon Of X INSTRS 1 PRINT B y INPUTB C A B 2 IFX S gt THENC A BIFX gt THENC A BIFX gt THENC 0 IFB lt gt OTHENC A B 3 CLS OUT PUTA 9 50 1 OUTPUTX 4 44 2 OUTPUT B 9 44 1 OUTPUTC 9 36 3 GOTO1 Our las Small Bytes pregram for this issie reached me sans the programmer s name Will the autnor please identify him herself 10 CLS A INT 6 RND 1 COLOR A A A PRINT REM THIN K SHORT TONESO 50 GOTO10 On the Inside What Really Happened To Ii A PERSONAL PERSP So many people have asked this ques ton thae we decided that NN was a perfect forum for telling Intetact s story onee and fer all its n interesting though somewhat depressing stor
30. 136 characters Expect to pay at least 200 more for the added print width One of the newer Epson printers is the FX 80 which is priced at 700 For speed this printer has a definite advan tare over others 160 charac ters per second Also its character dot matrices are larger and the re sulting print is finer in appearance Any pce printer frankly would be a good investment for your compu ter Their only disadvantage is that they are designed as parallel printers and require a special board to convert them to sertal operation You ll prob ably pay 80 to S100 mere for that conversion which you can easily per form yourself NEC Digital LA5O n the low end side of things NEC is probably best known for the 8023A printer However the 8023A is set up for parallel interface opera tion and apparently cannot be adapted fa serial use Their Digital LAS5O is however essentially the same machine equipped with a serial port This printer hae a buffer in which it can store information arriv ect a faster rate than it can print While this is a useful feature on many systems it is unnecessary for the Interact because you can control the baud rate via the software NEC has a reputation for high quality hardware so this printer would be a safe bet You can pick them up at many dealers even ifthey do not carry NEC computers We were quoted a Price of 699 for the LASO and if it s truly as reliable as th
31. 20 CIRCULAR MOTION Programmer Bod Fett Dearbom Heights MI 10 CLS COLORO 2 4 FORR 1038 C C 2 1FC gt 3THENC 20 FORT 0T06 28STEP 05 PLOTS6 R COMF 39 R SiT C 40 COLORO 2 4 FORT 17030 NEXT COLORO 2 4 FORT 171030 NEXT 50 COLORD 4 L2 FORT IT030 NEXT GOT040 STAR STRUCK Programmer Tom Doerr Cambridge OH 10 CtS A 5 8 38 FORT lt OTOLFORY 0305 FORV 0108 CoL ORO T U 20 D INT 55 RAND 1 NI RNY 9 C NI RNK Y i 30 N 0 1FE gt DGOTO60 40 F A G A FORO I1T0D PLOTF B N C FLOTG B NC AOTG B N 1 C S0 PLOTF B N 1 C F F G lt G 1 N N E O NEX GOTOIND 60 F B G B FORO iTOE PLOTA N F 1 C PLOTA N G6 1 C 70 R INT A N A S INI A N J IFR lt gt STHENR R 1 O PLOTA R 3 F 1 C P OTA R 1631 C R 0 90 F F 1 G G6 NaoN D NEXT 100 NEXTY UT GOTOI0 12 Notice to Contestants Some of you sent in multiple entries which is perfectly fine we didn t restrict the number of times you could enter We have printed afl the entries we could here If you don t see your entry there are two possible reasons We simply could not get some programs to load even after repeated attempts and tape head inal and were therefore unable to get program listings Remember that you should never write over a tape containing old programs or even standard audio recordings without erasing the tapes completely first Some muttipte entries were merely minor variations on a theme for exampie end
32. 35 57 YL C 120 UNES YUL 35 C 130 C C 1 140 IFC 4THENC LSOXLeXL 60 XH XH 17ON Vi i 180YH YR 181 IFXL l1BTHENXL XL I 1823FXL OTHENXL XL 1 1831FXH N8THENXH XH 1841FXH OTHENXH XH 185 F YL 7 7THE NYL YL 1 L86IFYL OTHENYL YL I 1871F H 77 THEI YHVH ISSLFYH OTIENYH YH 1 ISO NEXE 202 FORA 0T07 FOR 0T07 FORC 0T07 FORO 0707 COLORAS C D 204 NEXT NEXT MEXT NEXT 1000 RUN Aircraft lander Enhanced L Shelton Allen formerly an Ann Ar or ite and now residing in Japan Saitama Ken has made seme modifica tions te the Aircraft Lander pregram that make it more challenging and give you additional optiens fer control With his changes the program allows you to change between Manual and Aule Pilot at any time It also lets jeu cheese a blind instrument landing in which the upper part of the screen is blank Through keyboard input A Auto M Manua l V zVisual Approach n strument Appivach you can select your desired operating mede whenever yeu like Visual mode automat wally retums after a successful landing in Instrument mode Change and add lines as fellows 102 T 3 Oelauit operation Visual and Manal 108 GOTO 130 replaces GOTO 200 124 MOT XY J glaces PLOT X Y 3 130 Z2 PEEK 24529 132 IF 2797 THEN OC I 136 3F Z7 09 THEN OC z0 136 IF 72 105 THEN J 0 COLOR 0 0 0 7 138 iF Z7 18 THEN fm3 COLOR 0 4 2 314 GOTO 30 replaces COTO 200 332 IF lt 20 THEN J 3 COLOR 0
33. A MOV A D RLC RLC MOV DA JNC PPIC3 INX H PPIC3 XTHL DCR E INZ PPIC INX H XCHG POP H POP H POP B MV A 20H ADD L MOV L A MV AO ADC H MOV H A POP PSW DCR B JNZ SAVR POP PSW POP H POP D POP B RET CMSK DB 0 551 AAH FFH PIXPIC reguires two set up pa rameter for use You must supply the two byte address of the picture table location in the B and C regis ters and you must define the start ing X Y screen coordinates of the upper left corner ofthe picture in the D and E regi ter pair Let s say you want to display the picture nine pixels fiom the lelt edge of the screen and 41 pixels down from the top To do so you would pass the values 08H and 28H to the D and E register respectively Remember that in machine language the coor drnate 0 0 is the top left corner of the screen The following code as sumes you have already defined FACE as a label with an associated address LX B FACE address of picture table AIVi D 08H MVI E28H CALL PIXPIC Notice that PIXPIC reserves all the registers This makes it much more convenient for moving the picture our next step because it maintains the coordinates and picture table address This means you don t have to PUSH and POP the register before and after calling the routine each time Use a simple locping routine with PIXPIC to move the face on the screen The following code displays the image beginning at coordinates 40H 288 and moves it left
34. E Double Trouble ability to think ahead If you enjoy testing your performance in hign iension situations Catacombs will thrill and delight you Stemberg Text Processor Finally a word processor for the Interact that offers full screen edit ing With the Steinberg Text Proces sor STP you type your text and desired format controls directly into a text builer If the printed resultis not what you want just po back to the text bulfer and make the nevessary changes You can save your text fle on tape and reload it later for further proce ssing of course On screen editing is perhaps SFP s most important featuze You can in sct and delete characters as needed and the following text automatically shifts appropriately The cursor which moves beneath the lines of text lets you know exactly where you are in the text file at any time and you can move it anywhere on the screen The text scrolls beth forward and backward in response to your cursor commands A special churacter set gives you smaller characters II lines of 25 characters each Now let me warn you The characters look a little strange especiully the lower case Ict ters It s just u matter of symbol rec ognition though and the letters don t look that much different frem what you re used to quickly ad juskd to the appearance and had no trouble whatsoever reading inlorma tion on the screen And of cousse the rinted output the ultima
35. FOR ITO 19 FORI 1702 1 PLOT 0 158 1 3 30 PLOT8B 1 39 0 4 3 PLOT6S 04J 17 1 3 P0745 141 36 1 3 NEXTII 40 sala B66 IOISTEP 07 FORI 117013 X J COS N 50 PLOT88 X 23 Y 3 AOT7B8 X 30 3 NEXE FORI 1T08 FOR J 1107 60 DUTPUT 69 3 2 J 3 NEXTIN OUTPUT 78 18 3 OLTPUT 56 423 70 OUTPUT 55 42 2 0UTPUT 56 42 2 PL0755 38 3 PLOT65 57 3 80 OUTAT gt 65 59 3 0UTPLIT 45 39 3 FL0747 40 3 FORI OTOISTEP 05 90 PLOT79 20 COSII 35 20 SIN I 0 NEXT OUJAT __ 68 21 3 100 OUTPUT 73 21 0 0UTPUT 68 14 3 OUTPUT 71 17 3 AS INSTRS H centinuecdi on prge L5 13 Tidbits Remote Keyboard Walter Parker ef Las Vegas NV didn t want to lose the overlay capabilities for Compute A Color and Music Maestro so he didn t install his prwfessional keyboard directly in his computor Instead he built a slender oak cuse with a masonit base and rubber fect to heuse the keyeard He van an extra 1 pin cunnector out the back of his Interact and connected his keybeard with a 10 foet leng piece of rib bon cable He reports that it works 1682 and he can sit away from h iscom puter with the keyboard in his lap Brave New Controller Dan tel Thompson ef Legan H rebuilt his own joystick when one of h iswas ir reparably damaged He went to Radio Shack and spent 6 on a small box five push button switches and a potent iome ter Fellowing the connections e
36. IC RHO 75 RH 360 INPIFI O 400 0 370 RHD ABS RHO 0 ABS 0 380 FIH lt OTHONTH TH 2 Pi GOT0GED 490 FPR OME NPH PH 2 P GOI0340 400 IFTH gt gt 2 PMENTH lt IH 2 PtE GOIO 400 410 FPH gt 2 PITE FH M P1 2 000410 420 DEAYIK OXI YXIBX 430 FORI OTOBX Mit B NEXTI 440 ST SIM TH CT COS NN SP S KPO CP COS PH 500 CLS S05X NX Sl 510 IF TH lt Ph2ORTH 3 PI 21ANC PH lt P THENX XX SI 1 520 a PILZANOTH lt 3 Ple ANOPH gt PITHENX XX 530 IF S LANDX lt NXJOR S ANOX gt gt XX THEN600 540 SEC 0 550 FORY NYOXYSTEP XY NYI YE 560 Z FA2 X 570 GOSUBICND 580 NEXTY 590 X Ni S1 XX NX XE GOTNS30 600 FORX TOLO PLGIX 2 2 FLONL75 2 HEXT 10 FORY 21075 PLOI2Z 2 ROTUO TAA 620 AS INSIRE D ENO 1000 REM AOTER SUB 1010 EX X ST CI 1020 EY X CT CP ST eP 7 SP 1030 E X SP Cl SP SI Z CP RH 1040 SX 0 EXEZ BX 1050 SY O E Z B 2 1100 IFSEC 0F HENSE C 1 0 0 GOT0I240 11100X 0X SX FIX 0IK NDX I 1120 SJ t0Y S1 OL YP OY 1130 S2 SGH SX 0N 1140 FORXP H ON ITOSXSIEPS2 15008 1 1160 P P 51 52 1170 ri BXRENOS 0 0W 0 GO1012 80 FYP lt OORYP gt BY HENOS 0 0W 0 1190 IF Y P lt YN XP THENI3SO0O 200 IFYP gt YX XPHTHENI400 12 0 0 i 0 1220 NEXTXP 1240 0X SX 0Y Y RETURN 1300 YN XP YP 1310 IFOS 0JKEN1330 1320 PLOP 5 YP 4 5 3 1325 FOW mOTENOW J 1330 1P lt YXIKPITHENT220 1400 YXX
37. IC26 pin I4 in addition he lifted the Read lines on both RAM and R M and put them and the lines coming from 000R and S00R on a switch With that arrangement he copies the operating system from the ROM into the added RAM By holding down the reset button and throwing the switch he can access the RAM operating system Game Stopper Albert Narain of Amsterdam Helland submitted a way to wrile an interactive program in BASIC that is lime limited and still allows input fram the keyboard If you are familiar with BASIC vou knew that the INSTRS functien steps the pregram until a string the required length is entered Everything grinds to a halt including a program timer Albert has found a way areund this di lemma His solution uses only 102 bytes ef memery in its simplest form 10 AS FOR 0 TO I0 FOR J t4337 TO 14342 A PEEK J IF A lt 255THEN 30 20 NEXTJA RETURN 30 AS CHRS 90 8 14342 J LOG 255 A LOG 2 RETURN Albert says that if you only need the number keys then you can cither PEEK only at 14337 and 14338 or apply the VAL function to AS If the CR key is needed than add 13 IF PEEK 14336 251 THEN AS CHRS 13 RETURN New Tricks For An Old Keyboard Alex Kazim of Houston TX has a great use for his old keyboard He uses it to repair his joysticks when they can t handle Hot Rocks anymore The only tools you need are a soldering iren solder and a phillips screwdriver First you open up the jo
38. No other BASIC program ming puide covers Interact BASIC sPecifically For the more experienced programmer BASICALLY SPEAKING of fers agoed review a chance to pick up special odds and ends you may have Verona Wis 53593 UPDATE Repair Service Micro Video has expanded its service department In order togive continued good service on repairs Micro Video has just completed major purchases of additional test equipment sad pares stock Also 2 f ull cime service technician has been added to the staff These new addi tions will allow for quicker turn around on service and make it possible to offer special modifica tions like the forthcoming RAM expansion Of course all of the standard Micro Video procedures are still in effect Each unit get3 special atien tion each is checked ired fully burned in and then Checked again before it s returned to you What this all means is simple Micro Video mee all your Interact needs missed and ir puts all needed informa tion in one handy sourcebook Costing about the price of one piece of software the manual gives you a cturorial a full command reference and enough pro prams and routines to pet yop started and keep you programming for a long time CGuprright rofi Mito Wideo Corporation Ali righu reserved i a peT ae FRE O 16314 As long last she most asked for hard ware add on memory expansion is here recency had che pleasur
39. P o a T oe facility to translate in the other direc tion Lei me remind you that you can however load and run 8K BASIC in your 32K machine Why not use that inlerpreier to create programs you can share with your friends QS Wil you ship my order C 0 D Can you bill me We can ship your order C O D only if delivery is by UPS You must supply an address UPS can deliver to no post of fice boxes There is an ad ditional shipping handling charge for this service The shipping handling fec for C O D orders is 54 50 with two exceptions There is a 5 8 charge for shipping RS232 interfaces or Voltrax Type N Talk units C O D Shipping and handling on computers ordered on a C O D basis is 10 00 We do not invoice individual merchandise or re pair orders because of the added bookkeeping it creates for us Q6 I just placed an order How ong will it be before get it We try to process all orders within ihree days of receipt Shipping varies on location bat will generally not ex ceed 5 days Computer orders may lake slightly longer based on availa billy but are usually shipped within 2 weeks of order If you have noi re ceived Your order within 2 3 weeks you should call to report the problem Q7 Are you going to offer BASIC in ROM And should delay expanding my computer for thts enhancement Many of you have asked for this ex pansion and we are sull considenng offering it Other items such as the
40. be interested in his application he uses his Interact to perform dis counted cash flow calculations for vaiuc bascd planning He wroic the Program himself Senous business z r Do we have vour cotrect address Is your name spelled nght Please check your aailing label and let us know if changes should be mite FEEDBACK September 22 1931 Dear Editor About eight months ago I bought the cheapest home computer I could find called an Interact My main reason for buying it was to sec if I could use BASIC to devise a way of keeping rec ords and selectively pull the records that I wanted Then I would upgrade and buy a real good home computer There is a company out there staffed by a bunch of nuts that won t let me do it It s called Micro Video Every time I think of an excuse to sell my Interact and buy a different uwt Micro Video comes out with something that proves I don t have an excuse wanted hard copy Micro Video RS232 device I wanted more memory Micro Video 32K expcinsion On the phone with somebody at Micro Video mentioned that I would like to have another recorder port They ave working on using the Exatron floppy string I m still trying to think of an excuse but I know those nuts at Micro Video will outttunk me Don Biown Midpa nes CA Dear Don Have you taken a look at DREAM Ji will ter you do record keeping of this eS I 32K CORNER countined from p
41. dimensions It is now nine pixels wide by nine pixels high Therefore the first line of the picture table which defines those parame ters for PIXPIC will be FACE DB 09H 09H Next we must eonvert the picture to hexadecimal equivalents using the same method as described last issue for BY TPIC except that the bit pattern is no reversed The first line is easy as all the pixels are black BB 09H 09H BB 0H OH OH FACE Notice that each line of the picture still consumes three bytes in the table although the PIXPIC routine reads only the first two bits of the third byte in handling the picture because we defined the width of the picture as 9 pixels Also note that the last byte in each fine of the table is the same OH which creates the band of black along the right side of the picture FACE The actual PIXPIC code is quite a bit os and more involved than S DB 09H 09H DB 0H 0H 0H DB 15H 55H 0H DB 1FH 0FDH OH DB 1EH OEDH 0OH DB 1FH 0FDH OH DB OCH OCH OH DB OFH OFCH QH DB 03H 0F0H OH DB OH OH OH BYTPI PIXP1IC PUSH B PUSH U PUSH H PUSH PSW MOV H B MOV B M INX H MOV C M INX H PUSH H CALL 52DH POP D SAVR PUSH PSW PUSH B PUSH H PUSH H XCHG MOV E C MOV D A MOV C M PPICO MV B 5 PPIC DCR B INZ PP1C2 INX H MOV C M JAIP PPICO PPIC2 MGV A C RLC RLC MOV C A AN 3 PUSH H LXI H CMSK PUSH B MOV C A MV B Q DAD B POP B MOV AM POP H XTHL XRA M ANA D XRA M MOV M
42. each image but this would have ill effects it would erase other items that might also be on the screen and would create a flashing effect as the image moves You might also use the RFILI routine to erase each face before drawing the next This would fet you erase Only part of the screen but re quires moi code as you would have to change the RFILL table itself each time The image would also be wiped olf the screen from left to right which would make the mage seem to ex pand and eontract as it moves proba bly not the effect you seek 6 The simplest and most effective solution is to use the image it self to erase the previous one To do so though we ll have to modify the pic ture and its associated code Since we are limited to one byte at a time mo tion with BYTPIC we must add a byte wide band of black the background color to the left side of the picture E ay ma ay The picture table must be rede fined to incorporate the extra pixels and the horizontal size of the picture passed to the B register must be in creased to three bytes instead oftwo FACE 0H 55H 15H 0H OFBH 1FH 0H OEDHIEH OH 0OFBHJFH 0H 0CH 0CH OH OFCH OFH 0OH 0F0H 08H Change the instruction that passes the horizontal size to the B register to MYVI B O3H and youre ready to rll This time when you use BY TPIC to move the image to the right a trail is still left behind but is the same color as the background so it is in
43. ee iad Tree eniti stn is re i a AAIE A A AETA ry jmt ieee ts mot tare Aa pam e Lave heat eee EAL E i are j T pii ei H ala oE pa _ 1 Satara a 7a Lol m i ap d ri fe Y p a pens F oe i LF bF eo bee EE 5 T m tinh amp lle TES 5 Ta SEELEY oi ir RA Ore pk mA POT BED ary corer Te ena i a oe oe j qi a ean J5 p pci A miary nat Or ire Eta Mie hy ae a Eurig bel HL eee Cee F BEL St eo eee i Talar tte bela Way ppe SE o m dere Les Pb A ake ae Pe a i a eee 22 ls z deere an p i EE a 4 4 i pa it al og Aun a E E E Ee e mar L E ns i p pe 3 E R ies mo a a i T ann E p i i Pa i k k Tere Di ety Pe a Ba 1 re a a L tle ese ee af In our catalog supplement in cluded in this issue we have three new action games to titillate you no matter what kind of game hits your partiema fire button And if you re tke me Jumping dack Silver Dragon and Pack Wnrs will give you a good case ef joystick cramp What more could you ask for What s that Something for you more serious computing cen thusiasts Of course Our new Communicator Plus sheuld really give you folks something to cheer about teo JUMPING JACK JUMPIN Jock has entered a death def ying one of a kind compe tition to prove once and for all who is the best stunt man in Hollywood The challenge is te scale two faces ef a series of Sul
44. handle every thing from simple head alignment veeblanss to one machine that was on when the house was struck by light ning so that s what happens when vou hit 700 000 in Alien Invaders Actually that was the only unit in the history of Micro Video that couldn t be repaired The hardest and most time consuming problems to fix are those intermittent ones the kind thatonly happen when your friend has driven halfway across the state to play Mazes and Monsters and then disap pear as soon as he pulls out of the driveway Often the key to solving these unusual problems ts waiting for the computer to act up again In those cases the computer goes on the burn in rack to be tested byv a memory exerciser a program that forces the computer to mantpulate information continuously Other specially developed software helps lacate specific problems with colors sounds or joysticks When the screen finally turns red indicating a failure Tim or Ed can locate the problem However if nothing hap pens within a reasonable amount of time Sometimes we ve kept a com puter running for a month or more without being able to duplicate the reported problem Tim says the computer will have to be returned By iar the easiest computers to re pair are the ones that appear totally dead That s because the challenge is to make the unit do something anything They open it up and begin testing everything with their oscil losco
45. high speed access for applications requiring large amounts of data and updating facilities is now 2 reality on veur computer The Exatron Micro Sponge a digital storage device provides convenient access to your Programs er data from BASIC and machine language or through direct commands You can selectively store and retrieve as man as 255 ad dressabie files a teta data capacity of 60 060 bytes on n single continuous loop wafer microcas sette Data transfer at 9606 baud eliminates jong waits for reading and writing tapes No RAM is Jost te support thrs device snftware in an easily installed 254 PRON performs centrellev functions such as READ WRITE CERTIFY The MicraSponge can be used with both 16K and 82K computers Mazes and Monsters Adventures in the Third Dimension A D amp D stvle game with graphics that give you a three dimensional perspective during plav Choose vour race dwarf elf or human Then select a set oftraits that de termine your strength intelligence magical powers and more Now youre into afantasy the dungeon of a 7th century castle serrching its eight ieveis for treasures Dan Exatron equipped with the Micro Videe RS232 port Ideal for your own data base applica lions or for scratch pad storage dur ing program development the Mass Sterage Pack tncluces the Micro Sponge 2 wafers PR NM resident gors Jurk in ihe shadowy corridors vou may
46. incapable of taking code in The Ititerace s ROM is 2K and contains 10 tines to make the leteers accep input from the keyboard and controllers and Ralph Babson of Tucsen Arizona sent us this patriotic Microsofe 8K progam He called it ents read tapes and perform other utiliry rourines Without he ROM you would noc see the L TO LOAD TAFE xren when you turn on your eOmputet nor veuld you te able to read in a tape Some of you have asked abour the empry ROM socket tn the Interact It will take a 7716 and has been used y sotme experimen tots Fiowever Micro Video has no com mercial ROM available fo chat slot The socket is only mapped for 2K and as BASIC requires much more than that it is not possible co put ROM BASIC in that spet which some have suggested A p mers The technique ite slow is actually snaight forward You must sore the background in memory place your solen on the screen then replace the background color and place the token in iw new lecstion You can do this using che POINT fiuc tiot to store che background in a variable or viable array displaying che teken then wiping it ou using the eolor background eolot infotmarion from the POINT The problem is that this i quire slow In A ie language you can use G TPEX fot a pixel save or a block move as in the BOMBS AWAY Programmin Tutorial To illustrate chis point if you ll pardon the pun here s a short program thar uses che rechnique
47. intercept and disallow bad move at tempts a feature that should always be present in a game regardless of its tvpe You are not allowed to move up past the fifth floor in any building norcan you move north if you are al ready on the northmost wall etc As well as being able to move around n the array game beard you 7 can also store things in the array represented by numbers to play a part n the action Every good ad venture game needs to have other elements present and since ours is taking place in office buildings we scatter desks and potted plants around in the offices The program does this as soon as you execute it using random number generation to determine what will be in each oltice lines 30 130 Any given office may contain a desk represented in the array by a I a potted plant rep resented as a 2 or nothing at all a g Each time you makea move the program checks the new location in the array to find out what its con tents are and displays in additeon to your location what you see in the room lines 200 260 You might memory permitting even add a fifth dimension one that represents a city the buildings arein DIM Al2 2 4 4 4 The abeve array could hold infor mation on three different cities each containing a trio of office pier 2 However that array has 1125 ele ments 3 x 3 x 5 x x 5 That s 4500 bytes of RAM so such a game would really only be feasible on
48. lets Aen here paneer in ii wierd f players sharpen their skills at the dif ferent levels without petting tired of the game Provide for increasing difficulty within skill levels Especially inaction games play should become pro gressively harder as play continues This technique Bives new players a chance tu get the feel of a game and builds tension and excitement as a player s skill increases In strategy games you May want to implement a dack up option that will allow the player to take back a move before completing the turn Backgammon for example has this feature it will let you revert o the be ginning of the move at any time during your turn Some gumes like Chess also include an instant replay option that lets you review the progress of the game Seme gaines ure well suited For multiple players Allernate players turns in such Baimes rather than bav ing each player complete a game be fore the other has a chance to play Breakthrough is deficient tn this re spect Alternating phiyer turns at ap propriate points in the play tends to breed more of a spirit of competition Identify players by name within multi player games or even singte player games People wst love to see their names displayed on the sereen especially if there is a high score as sociated with it Consider allowing skilt level sefectian for cach player in a multiple player game Particularly in educational games such
49. machine language training course is in rhe works and BASIC in ROM is being sexeously eonsidered We ve added eofumns to rhe aewsletux which has increased co 12 pages and is stili free let me pointe out It s remarkable that our little micro considered a dead product less than twe years ago ls now so well supported feel like hanging out a sign saying WATCH US GROW Let s all grow Use your computer Ex pand your knowledge We ve only just tapped the surface of whats possible Read l get every computer magazine can Fhey cover a lot of information chat can be transferzed to the Interact Bwe for 2 hardware information Sofeside has loads of BASIC games Dr Dubbs gives you ad vanced toftwate information Computing with ics special issues on graphics music erc can help you take full advantage of your Inceracc s capabilities 30 Micresoinbu ing is one of my favorites I know it s written for TRS JO users bur che idess are great On Camproing and Personal Compra are ter tific for beginning users Buoks are helpfd eoo Mico Vid s BASICALLY SPEAKING has been touted as one ef the bese BASIC tutorials around and it s completely Incerace specific Once you ve read that cry TheA to Z Book of Computer Games TAB 1602 7 95 which has 26 games easily con verted co che Intesact environment Als will frinvo 4K and each is presented wich a tutorial on techniques used Starting on machine language Pick up
50. more Perhaps yeu should think about learning to program in as sembly language there are many good books on the market to learn from and il sounds like you re rady for that step Dear ASV l just got my VideeCalc and all 1 can sav is WOW I never would have believed my Interact could do all that hanks Ryan Smith leresi Greve OR Dear Micra Vidco f love my Interact and RAM Poges Keep up the good work I would like to have a booklet describing what each Memory location holds and what each possible P KE combinatin would do These listed in Bast oliy Speaking are helpful but the list isn t very extensive A lay ge table lisung ail lecations giv ing the results of all possible P KEs would be quite an undertaking but l think the re sults would be worth the trouble It appears that Interact Electronics had planned lots of goodies for our compu ter An old product cotal and price list shows the I6K Model One Standard what we ve got a 16K Model One Pre fess io a ithe standard plus 2 port RS232 printer and communications interface and u 16K Model One Prulessiona Plus the Professional with an additional 144K ROM containing Level II BASIC pro gram editor printer aod communications software The Prefessivunal models were to be available in the winter of 1979 Wil Micro Video s R M BASIC include edi tor printer and communications soltware How is work coming along on io de crease the character
51. on the screen to location 10H 28H LXI BFACE MV D 40H NV E 28H LOOP CALL PIXPIC DCR D MOV A D CPi LO JNC LOOP One of the most logical places you might want to use motion is in a game Ppregram where the movement of the image is controlled by joystick input Here then is a simple routine to move the face via the left joystick The picture ftrst appears at location 30H 28H Therealter you can move it up down left or right using the lefl yey tick MVE Devel DAE Earl NE IS PACK SATAHTING N acme eee BSTARTING Y COMDRED MOVPE CALL Othe MOY Fr LEBA PU KE AG LEVT poy STE K CPL DIIS JNZ Mover IN R IET MONE JNP ONPG WS FA RH JZ SARS INR D TUCKS SONG JP SWYN Morz eti gi SNF LiL Fa URUMAK t IWA t INP MOP MAPS CPE egi dE MOK AR F 3 IMM NW ARD AN p Mr ON A word of caution about this rout ine is in order It does stot check for the boundaries of the screen We advise you net to move the image off the screen in any direction as the re sults are highly unpredictable You may inadvertantly destroy part of your code if you do There you ure You now have all the information vou need to create your own moving pictures Have fun and let us sec the results my 7 At various times we ve been asked about converting the Interact to video out operation so that it can be used with a monitor instead of a TV set For those of you who may be in terested in modifying our computer this
52. one sport and olten vou are your own worst enemy And ethers like me vonterueced as Wige 20 3 Putting a picture up on the screen is no big deal Getting it to move around quickly and smoothly is another matter altogether In this ar ticle and its sequel next issue we ll takea look at two Move routines and show you how to pop pictures ontothe screen and move them without the image flickering Most of you are probably familiar with the ROM subroutine RPLOT which lets you output a picture as a bit pattern on the screen RPLOT has its drawbacks though It only allows one color per picture and is also rather slow Too slow in fact for complex arcade style games with last moving gvaphics If you want to know more about RPLOT see the oo Away Programming Tuto vial The Move routine we ll examine this issue is BYTPIC It is a byte oriented routine that is very fast Al though it can be employed to move pictures on the screen it is chiefly useful for moving a stationary image from memory to the screen Next issue we ll cover PIXPIC which though not as fast as BYTPIC is more suited for moving images on the screen Before getting into specifics about BYPTIC let s briefly review some of the basics of graphic display that are relevant to the use of the routime As you know the screen display is 32 bytes 128 pixels wide of which only 28 bytes 112 pixels are visible on a typical TV screen and 77 lines tall
53. peak popularity Pac Man grossed over S8 million a week Poor games seldom get past first base in sales distribution or use If you plan to design develop and eventually sell your own game you may wish you had some guidelines to improve your chance of success We very strongly feel that i s not so much the computer used to develop a game that determines its popularity but the techniques that go into building and programming it We use the following guidelines to evaluate games that we buy from de velopers for inckusion in our product catalog They are therefore somewhat stanted toward our environment You ll find however that the same guidelines apply to games for the Apple RS 80 Pet or other personal computers and even to the specialized coin operated arcade games We ve tried to keep the list general so thal the suggestions apply to different classes of programs as weli action strategy adventure or learning all set in u game environ ment Game Operation First of all you must evaluate and understand the purpose of the game Is 1 am action game a strategy game an educational game Develop a scenario and f your program into it Lay out the whole structure of the game before you ever program byte one Try to cover as many of the What IT contingencies as you can and try to make the game us varied as possible You can fit a surprising amount of complexity into a small amount of memory if ywu kn
54. please sort ffis method of complaining certainly deesn t get him better service You can start giving us your feel ings on various issues by completing and returning the survey form on the back page of this issue Tell us what you want or don t want to see in the next issues of RAM Pages Be as specific as possible If you d like mote hardware information let us know what technical information you re looking for If programming is your area of interest what kinds of arti cles would you fiind most useful BASIC Assembly language hexa decimal Let us know how you feel and a better more useful publication will result We ll analyze and publish the re sults of the owner survey in an up coming issue so you can see how what you want compares with what others are asking for Until next issue Sue Denim Editor MICRO 23 VIDEO Design and Production Brian J Meller Committing Editor C F Walker Conuiboting Writare Oavid Ross a John Qov jie um Wilkins n Arbor MI 48109 Copyright ideo Corp All eights reserved He aa A fa Subscript ign rate 20 00 for 1 year 4 issuea fer che U S A ita torritorial posatssions ond _ gn mill For subscription q Canade 32 00 fo elgn minh at Micra infermaton ca Featured this issue are three new a i lg from the upcoming catalog here s a fast paced single player game a unique two player action strategy g
55. production lead limes this item won t make our up coming catalog but look fox it in late summer or carly fall Q17 Now that yuu offer an assem bler isn t the Munitor program have odselete Most certainly not While the assembler cditoOr package provides an caser methal of generaimg machine code the amount of actual object code you can produce from any onc source or text fite is limited by the available RAM m your machine The Monitor lets you piece together blocks of object code you ve gener ated from multiple source files and save them a one compiete program You can also use the Monitor to cor reel errors or modify the program without having to repeat the entire as sembly process QIS Are you planning to come out with another Adventure game Good news for our adventure aficionados An all new adventure The Haunted House will be offered in our next catalog Q19 Will a Noppy disk ever be avail alle for our compuler To be honest a floppy disk expan sion is unlikely But those of you who ve been waiting for mass storage for your machine check out the Exa tron Stingy Sponge article on page of this issue Q20 Who eurrently manufactures the computer Manu Tronics originally produc ed the computer for Interact Electronics and continued to produce machrres afier Interact s demise in 979 to geet rid of related stock they d purchased Micro Video now holds the only man ufactun ng l
56. s ON THE INSIDE formed Micro Video in June o 1979 to pursue the use of the Interact in promotional en vironments such as trade shows and point of purchase displays When Interace folded Micro Video acquired Interact in ventoty and manufacturing tights 80 en sure a supply of machines for chose com mesciel applicat ims but Dave had no in tention whatsoever of picking up where Incesact left of In fact ic wasnt unai March 1980 that we decided to cest the ominid on Page What s hex or hexidecital Our standard number system is dect mal that is base 10 Numbers run from 0 through 9 The system most com monly used in the micro world however is hexadecimal that is base 16 Because we only have 10 digias in che structute of our counting system we must have some way to represent the other six dipits in the hexidecimal counting system Soa we work within another familiar system the alphabet The letters A through F are us ed Octo 9 then A to F The decimal 20 is OA in hexadecimal 11 becomes OB etc When we PEEK or POKE through BASIC it expects decimal numbers but if you wotk with machine language you must learn to eount in hexadecimal And if you get a reference card of in sccuction cedes for 8080 machine language you ll usually find they are given in hex notation What s an address The 8080 CPU can tak to or keep track of 65535 decimal byces of infor mation A byte is a number ftom 0 to 255 d
57. sets The data sets should be placed on separate DATA lines or groups of lines such that each set starts on a new DATA statement 10 DATA 110 55 110 55 110 55 139 216 BEETHOVEN S STH 20 DATA 97 247 431 61 117 68 1314 61HALLELUJAH CHORUS 30 DATA 200 150 179 55 168 119 200 100 DRAGNET THEME 100 CLS COLOR 0 1 3 7 110 QUTPIUT NAME THAT TUNE 10 60 2 120 OUTPUT PRESS KEY 24 481 130 OUTPUT 1 2 OR 3 21 40 1 140 AS INST RS 1 150 IF A e 1 THEN RESTORE 10 GOSUB 300 GOTO 100 t60 IF ASw 2 THEN RESTORE 20 GOSUB 300 GOTO 100 170 IF A e 3 THEN RESTORE 30 GOSUB 300 GOTO 100 180 GOTO 140 200 FOR Pai TO 1000 NEXT RETURN 300 FOR Pel TO 300 NEXT 305 FOR 1 1 TO 4 READ A B TONE A B NEXT 310 GOSUB 200 320 READ O 330 OUTPUT 0S 56 3 LEN O 25 3 340 GOSUB 200 350 RETVUAN Note that the program doesn t reset BASIC s data pointer until a key has been pressed Then based on the value of the key it issues a RESTORE to a specific line number You might try expanding on this idea to create a game with more tunes to name or one that randomly selects tunes from a list In the latter case you might want to put your RESTORE statements in a set of sub Here s how you might use this form of RESTORE in a program Feedback continued from page li price which does not include the comroller software required to use this device with your machine You d have to modify your computer hardware to add a floppy d
58. sewer water whech had come up from our drain There was no telling how long it was under or the damage but we E uessed at least a couple of hours lhe first thing we did was to get it out of the water We drained it out and then had it checked out Noth ing was wrong except the tape head needed cleaning We are extremely happy to be Interact owners Faithful owners Mike amp Dave Daugherty Marshalltown Iowa GOSUB con tt apologies fo Charles Pickens Dear Micro Videx Here in Bayfield my dad owns the cable TV company As you know the Interact comes out on channel 3 We got it changed to 4 so now we use the Interact to advertise items on TV We have about 360 people on the cable We also play games on it too i should say I program and play games Two kids in our class room have Atari video games and they told me that the Interact is junk even though they d never seen one When we got it on the cable TV I called them both up and told them to turn on channel 4 Well they have both seen the games Alien Invaders amp Packrat and they think the Intcract is a good computer In fact they like seme of the games better than Atari s I had a lady call me and ask me what kind of computer that I was using She loved all the sound and graphics told her that it was an Interact and about some of the games you can get and she sure was sorry that she Ron ht a TRS 80 Well that s all the Int
59. success with machine sales thece the special training and exrensi ve support the test market etuired rap idly consumed any profit from the sales It was also apparent that to be eompetitive wrth other micos a number of enhancements were required Interact was tessured by Montgomery Ward and others into som micting to several major a D o ct3 ail at one time The result was thar the projects got attention in fits and start as pressure from one source or an demanded it Ac chat time Intecacr had five pieces of software in the werks as well as ROM BASIC an RS232 port and an intecfaee co the EXATRON stringy flop py any one of which is a major et A ing These were al under development fcr the Model 1 of which thee were several thousand unsold in invencery Mesn while Interact was proceeding with another highly secret project develop ment of the Interact Model LI At the end Interact was itivolved iri a desperate struggle to keep it corporate head above water With no new products being released sales poor and creditors pounding at the door che investors decid ed the situation eould only get worse December 31 1979 Inreract Etectronics closed and locked their door for the last arne Enter Micro Video If you re wondering how Micro V ido became the support source for Interact eomputets let me give you a licle history on that too Our president Dave Ross whom you will remember from last issue
60. the L key to turn on the tape motor then depress the READ cas setle butten Just below the tape door is a small circular hole Insert your alignment screwdriver straight down into the hole and turn it slowly to the left then right You should be able to hear the audio tone change from strong and clear to weak and muddy When you hear the loudest and sharpest tones the tape head is aligned accuralely Now try loading your tape again to see if the problem has been solved Still won t load The next logical check to make is for motor noise Motor noise generally results from a faulty ground Use RESET L to get The Computer Doctor the tape motor going then turn up the volume on your TY f you hear a load scratching sound your compu ters got motor noise The culprit is usually a leose spacer To correct this pioblem you ll have to take the top off your unit so grab a screwdriver and do so Four screws hold the plate covering the main electronics assem bly in place Beneath each of these ts a spacer Remove the screw in the lower right comer You will then be able to see the spacer that generally causes molor noise Insert a flathead screwdriver into the hole and care fully tighten the spacer When you ve done that try loading the tape again to see if you ve cured your computer Still feeling ill Don t worry there s hope for your system yet The tape drive contacts may de the source of your read
61. the numbers in the safe s combination and one of whom has a clue to their sequence How sharp a detective are you Can you crack the safe and save the world before it s too late ee eee 17 95 Heads Up Pinball The original arcade game the precursor of video games goes electronic on the Interact Yes folks your computer is a pinball machine with HEADS UP PIN BALL Pull the plunger and watch the ball bounce nto action Be quick on your flippers to keep the ball in play aiming it to knock out heads and score points Hours of fun for the young and VOUNPEY 4 oa 19 95 BET 10 BANK H0 HINNER BET RETURNED One Armed Bandit You don t have to go to Las Vegas or Atlantic City anymore to play the slot machines Save money all around by turning your TV into a One Armed Bandit Superb graphics in this assembly language program let you watch the wheels spin when you puil the handle down You can borrow from the bank if you run short on cash but don t quit before paying back your loan 17 95 with complete heavily commented source FST IC ae ee ara ee 24 95 Prices speahicauens and avatlab litv subject ce change withaut nutice Order Form B Name EEN a A ooi iAi P City _ Phone Please send me the items listed below Qty Q Payment is enclosed Di Billmy Visa U MasterCharge MI Residents 4 Tax Shipping Handling S 3
62. the Interact and programming it If you have a question send it to Micro Video attn HELP We ll try to answer all submissions Q Why doesn t somebody offer a replacement characrer chip for che Inceract s0 wv can hace smaller letters A Many people would like this bur the treason it hasn t been offered is that no character generator chip exists All letters generated are drawn by a graphics routine in the ROM toa bit map in the ROM As all graphics are hard ER 100 NEXT CiLS RETURN m atm SMALL BYTES and ll publish some of them The gram judged best by our judge 1s a prize Below is an example eee with Microsofs 8K ki boy Ir makes the most awful noise you can imagine At last a pro gram that has absolutely no useful purpose except fun 1 21 B 72 RND 1 1 C 4 RND 1 41 D 4 RND 1 1 C 0 77 GOTO10 ware set O the 11 2x77 pixel screen format changing the ROM would nor help Although ic s technically possible co mod ify che Interact for smaller chac acters it s a major undertaking for every computer requiring extensive internal modification Most people wouldn t be willing to pay what it would cost to make those changes If the characeee size is really a problem for you you can always install an RS232 port and get a CRT rerminal You lose graphics capabilities and it is a rather expensive approach but it s cur rently the only workable solution The lneerace
63. the base of the Scarlett Mountains from evil monsters Fireballs are your only weapen Giant Eagles are the sylphs only direct cnemics Other creatures are only out to destroy the dragon Eagles can swoop down grab the sylphs in their talons and carry them off to their nests There the eagle and sylph mutate to form a hideous harpy Harpies possess a deadly Magnetic power dont get toe close The elusive whirlwind genies can be come invisible at will The manti ceres who shout peisonous tail spikes in any direction are probably your most formidable opponent ne hit from a tail spike or touch by a genie harpy or eagle and you ll have te gulp a bottle of your magic regenerating potion Beware You start with only four bottles but you earn one mere with each experience level you complete You score points for destroying the attacking monsters You can earn bonus points by shoeting down a svlph carrving eagle catching its prey in midair and helping your sylph isorry gently to the ground The ferocity of the monster waves depends on the skill levei you choose With skill luck and courage voull reach High Level Dragon the ultimate anal PACK WARS Both of these games are exciting but if lhad to choose enly one of the three I d give the nod to Paek Wass For me it has all the elements for video rapture good graphics fast actien and the opportunity tobeat up en someene ether than
64. the meantime you can devise your own system The switch Russ descnbes doesn t actually allow for simultaneous dua use but it wil allow you to hook up both devices and switch back and forth without having t unplug either device You ll need a double and a triple pole double throw switch as per the schematic below Vl leave the wiring and choice of a box to put it in up to you at iced oer maior on re i iiin Dipi 7 a Lia Frente heal bigi l hee rs I E 7 Caonypuier i through direct entry with the Monitor Rather than using actual hex values vou enter Intel 8880 mnemonics These are combinations of letters similar to functions in BASIC each represents an instruction to the micro precessor In general learning and re membciing these sets of mnemonics ts far simpler than having to work with ll the various hexadecimal combini tions they represent The mnemonics are processed and converted to machine or object code for you au tomatically With Assemblex Edilex you write programs in two fundamental steps First you use Editex to enter the source code mnemonic instructions Then you use Assemblex to convert the mnemonics te their hexadecimal equivalents You can enter about 8K of text into a source file on a 16K machine On a 32K your source file can be considerably longer up to 24K The ratio of abject code gener ated from a source file ts roughly lo 4 if comm
65. the mex Sage somewhere so we know Whatto do with it Writing ce Bulletin Board on the envelope would be greatly appreciated 3 The message has to have something w do with the Inter act Thats fairly broad when vou think about it 4 The message has to be legi ble Please dant assume we can read your handwriting pust be cause vou Can Please type il possible If net please print And please write in English whenever pessible D We reserve the rightto reject any affensive nudeniat We re serve the nehi w edit all sub TH ASSIONS G Messages have to be recevel by Micro Video at least 6 weeks before the publication date For next issue Messayes ae due 6 15 83 Join the crowd Be a RAM Pages subscriber W Jans lina ae oom caus ca hg iim mae Fr Here s What You ll Get When You Subscribe to o Four issues of RAM Papes Free access to the Bulletin Board o Valuable discount coupons for Micro Video Products Previews of new software accessoties Contests Computer Doctor e Hardware Hints Programming insights inside information about Micro Video 50 off any tape of your choice when ordered at the same time as your subscription And much more MICRO J VIDEO SUBSCRIPTION FORM Basic Subscription Rate 20 per year U S and Canada only All other countries 32 00 Sue Denim s Subscription Special With your subscription to R
66. with its functions and operation If you re familiar with BASIC but want a reference source for the indi vidual commands and keywords Basically Speaking will fit the bill for you too Machine language while more complex to learn and use does some things much better than BASIC For graphic animation machine anguage wins hands down for example Because there is no in termediate interpreter to slow the operation down you program byte by byte changing hexadecimal val ues in the computer s memory loca tions you can produce games or programs that have fast paced ac tion and speedy fluid graphics If you aren t quite ready to take the big step into writing programs entirely in machine language you might start by integrating some machine code routines into your BASIC programs calling them when needed with the USR function That way you can include fast moving graphics in your programs without tosing BASIC s ease of calculation There are two tools you can use to produce machine language pro grams or routines on your Interact There s the Monitor Plus which puts you directly in touch with your computer s memory You change hexadecimal values in various memory locations to get the results you want This is the nuts and bolts level of programming Your other option ts the Assemblex Editex pair These programs bridge the gap between BASIC and machine lan guage providing an interpreter to make
67. you seem to have something going here Brad Branham Houston TX Dear Brad We agree with you The keyboard 18 metil Youll love our new keyboard See article on page 1 Our price on the Stringy Floppy ts only 30 00 higher than Exatron s list cominued on page 12 Lt Great Restorations i BASIC has a feature we weren t aware of until re cently An astute user Bob Morrison of Franklin Ohio passed this tidbit along to us While we documented it in the last reprint of Basically pind here are details for those of you who bought after the first printing of the manual As you probably know the RESTORE command re sets BASIC s internal data pointer to the first DATA statement in the program This allows you to reuse sets of data as needed during program execution But to ac cess data in the middle of the data Ist you must have some way to bypass data values you don t want to use One way to do this is to use a dummy read loop to take in then discard unwanted data This can however be a cumbersome and time consuming method of handling your data As it tums out there s an easier and faster way to con trol BASIC s data pointer The format ef the RESTORE command allows you to reference a specific set of values in the program by including a line number on the RE STORE command e g RESTORE 1350 To use this form of the command successfully you ll need to organize your data values int distinct
68. 0 SOUND4 20 FORD 1T0100 NEXTO SOUND7 4096 PRINT UGH PRINT FM DEAD i t Wier ses the Interact can only clispley 4 colors Ran this 8 BASIC small bytes submitted by Anthony Watcon of Woodland WAS ore reat surprise 1 DATA6 193 5 194 2 78 0 0 50 0 16 61 194 0 78 62 6 0 0 0 0 0 0 0 195 0 2 FORA 199687019994 READB POKEA B NEXT POKE 19473 0 POKE 19474 78 DATA76 3 CLS PRINF COLOR DISPLAY BY ANTHONY WATSON FORA 1T02500 NEXT CLS J USR 0 Bob Alpert of Delran NS created this inie program thar compuies a checksum on Microsoft 8K BASIC It checks far damage fron improper loading or cerent POKES and tt takes abont 0 seconds to run The oml x Problem had with it was that it udwavs told ie BASIC had em errar and mine seetsedta run okar 10 CLS T 0 PRINT COMPUTING FOR1 24576T032767 20 A PEEK I T A T NEXT IFT lt gt 1002200THENPRINT BASIC BOMBED END 30 PRINT BASIC OK Frunklin Ohios Robert Monisan svit in this colorful Level tHE BASIC pregan White the graphics are quite slow in developing the final impact is dramatic 1 CLS FORX 0TOSS6 FORY 0TO38 C SQR X X 3 PLOTS6 X 38 YC PLOTS6 X 38 Y C PLOTS6 X 3B C PLOT56 X 36 C NEXT NEXT FORA QTO255 3 FORB 0T07 FORCs0TO7 FORD 0TO7 COLORA B C D NEXT NEXT NEXT NEXT The Winner s Circle Our judges were split on which of the Smal Bytes emnes should be awarded the prize of 350 00 in product credits One of the finalists submitted a progra
69. 39 PLOTS7 HOC 3 H 39 1 PLOTO 39 H C 2 57 1 H NEXT 9 o 38 ii OTS 7 38 2 FORI O10 ISTEPO C POT O 80 H SGN C C 10 J H AND3 COLORFR C O FNC FNC 2 FNC 3 FORK OTOC NEXT NEXT STRANGE VIEW Programmer Mehal Patel Chiefland FL How this program looks will depend o what was joaded into your computer sefore you enter and run it CiS COLOR7 6 5 4 P KE2 4887 10 POKE 24886 10 POKE 24885 3 FOR 17047 POKE24889 I PRIGT NEX T POKE24887 46 Or for a different effect 0 INDAY 1 CLS COLOR 7 6 5 4 POKE 24887 10 POKE248 6 10 POME 24885 11 3 FORI 4710 SIEP 1 POKE2 4989 1 PRIPET NEXT POKE24887 46 4 FORI NOIOO REXT CLS ASSINSTRS U COLORO 1 2 3 5 PODKE24889 0 7 WINOQW77 SAILING ALONG Programmer Peter Finch Tigard OR This 8K BASIC program uses a machine language routine which is encoded in DATA statements in line 1 3 Note this program will not run under 32K BASIC control unless you first change the POKES identifying the routine and the USR Call DATAPOCBAMFFCCPOF PPLHGMOAIFFBBAABACBAAAAAD HIHOCDKGC OXGAPBHBHAPBHBHOGAH OATADCAABAANMCBEF FCBABCGOFCBHKAAQDOOPBBPBPBRPPFOGAH BCPGAAPGAAAACLHMLFMC ee eee ee ANONCA A CLEARIO0 COLORG 3 0 1 CLS F RI 217601021852 IFX gt LEH CS THENREADCS Xal 5 init ald OS C X J ASC MIDS CS X 1 11 2108 X X 2 NEXT X 947 6 ane POXEX 1 85 PLOI0_42 2 14 36 FORI 07050 X 5 109 RNDT 1 L RND D PLOIX 44 3171 0 NEXT FORI 010
70. 4 M 0T24 1 164 1 3 52 1 2 NEXT FORI TO012 8 X 16 SQR I 0 0 169 Pt O150 X 57 LX 2 172 NEXT PLOT5 21 3 1 37 Q FORM 247056 X 43 18 SOQR I tl 4 DBT 2 M 54 27 SQRO i 30 27 2 X 10 FLOTAS MAE NEXT FORI 1 7029 Pt 0153 1 54 1 3 1 L NEXT f USR 0 gt W N d MANDALA Programmer Oick Ricker Cornville AZ Now we know what people in rural Arizona do for entertainment at night Actually Sue Benim a former resident of Jerome justa hop skip and a jump from Comville sez she already knev 10 CLS COLOR4 1 2 3 POKE19215 25 DIML 96 J 0 A 17517 8 1767 0 17678 15 0 17518 E 96 F 32 PRET LOGE FT UP PRINT PRINT PRINT EREINT AS CHR 1 B3 CHRS 8 20 PRINT FOR 17 9 PRIPTAS NEXTI FORX 2T011 FORY JTOX 1 INT X 3 3 X 25 25 FORI OT02 U3 I A X E CV F AIL 2 A Y EAX F L J 3 B X E Y F 30 4 8 Y E X F 109 5 C X E Y F 1 LU 6 C Y E X F 35 1 7 O X E V F PEL 8 0 Y E X FF 8 NEX NIKT PRINTBS NEXE CLS 40 B C 2 0 2 E 24 255 FORI BIOU IF C gt ETHENC B 1 INT RND B D E 4 POKEL I C C B NEXTLA 0 C 25 0 3 F 85 50 FORI B10J IFC gt ETHENC 8 V F JNT RNO 8 0 B IF PEEK LI THENV A 55 POKEL C C B NEXTI GOT05O PATTERNS SNOW BLIND Programmer Anthony Watson Woodland WA Two entries in one you ll see a different effect depending on which of the two modes you Selec
71. 4 2 7 replaces iF Vee GOTO 342 334 F lt 0 GOIO 342 He was also frustrated with the pro grams etall warning indicator which only told him he was stalled when it was already tev late lo recover So he added the following changes and now gets a warning befoee he stalls 289 GUTPUT XS BSCS 08 3 8 313 F aNT V SIMONA Y FF gt OTHENKS 290 A ENT 682 V0 1 A lt LO ANDH 8THEN TONE 100 500 29 IF A lt 100 AND H 8THENO 0 3 Shelton also got tired of what he calls the same ultra simple approach when BASIC and the program are first loaded so he added a randomizing factor with the line 10 A RNOl PEEK 24559 He says he s also made ether changes that allew increased maneuverability such as stalls S0degree turns rolls and inverted Night If he makes a bad ap proach he can even tum around head eut and ceme buck in for anether trv He ll be hnppy te share these other changes with anyone who s interested Keyboard Comment Jetin H Petors of Wayland MH teld us that he found steh 6 of the instructiens fa installing the new professiena keybear unnecessnry He was able to angle the keybeard into blua without first rem v ing the prescribed five kevs Altheugh anyone whe has the new Keybeard has undeubtedly aleeady installed st you may lind this information useful if you ever have to take n back out By Popular Demand A Novel Plat We ve had se muny requests for listings of Chuck Yount
72. 4CFD 4CFE Hex The values in these two locations will give you rhe address of the end of your BASIC program least significance byte most signifi canr byte Your machine language subroutine should begin at least one Interact The Big Apple thae is General Motors is using an nterace in their building lobby display ar the GM Plaza building in New York City to provide a changing display that explains the many ticids in which GM does research The special custom software utitten by Micro Video uses text sound color and graphics to tell about the General Moroes that doesn t build cars The program is planned to run for eight yrs as part of that display and in the firsr six monthsthere have been abselurely no Conquers byte higher in memory than that Add the length of your subroutine to deter mine if you re in danger of r un ningoutof memory Your subroutine muse srop before SFCO or you ll clobber the ROM storage area When you recertain your program is fineshed load in your subroutine at the specified address and POKE the ending address of your subroutine into 19709 19710 again LSB and MSB Now when you CSAVE the program the whole works will be saved in one srep Try it you Illove Te If you re a beginning programmer and want more informanon on PEEK and POKE consult BASICALLY SPEAKING You can gee rips on machine language Programming in the BOMBS AWAY Programming Tutorial g problems wi
73. 8080 Z80 by Spracklen available at most compuser stores or thtough Micxo Video 8 95 Most importane of all use your com puter Turn x on Write a game disassem ble the ROM tun a printes balance your badget wire in a wehe mron simulate WWII access a timesharing system try machine language play a game do animations write a teaching program play music Explore The in eeract gives you the possibility fot expan sion not just hardware but expansion of the mind With your eompyrer you ll either glow eo new vistas tx gow sele bur grow you must Come on guys fiddle those bits Sincerely Wir fog Marv Long Editor PS Don t forget to wrie Your thoughts and ideas are welcomed g da dh dh dh dh dh s Answer to Last Issue s Puzzling The new BASIC manual sa COMPUTER TUTOR Croasive NOTES Two games share the winner spot for che favori Ineerace program as shown bg your responses ro last issue survey are Earth Outpace f and che Troli Hole Adventure Well cakk about them so chose of you haven t tried them will know what you re missing and also wake a peek ac Micro Video newest game release GOOFY GOLF EARTH OUTPOST I 1 player Each Outpost 1 is the biggest seller Micro Video has hadrodate Although it was patterned after the popular spaee war atcade games it has fearures and a style of play that make ie unique The ob ject of the game is to defend two
74. AM Pages you can order ANY TAPE AT HALF PRICE One tape only Cannot be used in conjunction with any other software coupon Atl you have to de is subscribe AND write in the magic words below that Sue Denim gave in the last paragraph ef her column en page 2 YES want to continue to be an active member of the Interact community Send me the next feur issues of RAM pages published quarterly Mame a Street Apt City State Zip Fer prompt delivery we must have vour 2p cede Yes want to take advantage of SUE DENIM S SUBSCRIPTION SPECIAL Send me 7 at half price ihat ate Hiper Cl Payment is enclesed Subscriplion Check U S Funds price tape Money erder TOTAL PRICE Please charge my Visa Exp Date Mastercard Exp Date Make cheeks payable le Micre Video Corporation Mai in enclesed pestage paid envelope er send te RAM Pages Micre Video Corp 305 N First St Ann Arbor 3 48103 Te subscribe by phone with your credit card cali 1313 996 0626 promptly hooked me Since that time Ive spent at least one weekend a month using if After spending 14 manths mre lm not a meathead en the Dwil Hole the Mysterious Slansion was x two weekend snap He tecently bought the Mazes and Monsters Hor Dame And to top 1 off he sald me his litera Hor Damn again Now how do lea on vour list to receive KAA Pages ond goodie lisis Sin
75. D Woodward reports that the program takes approximately 40 seconds ta cun and identifies 8 sum answers He feund however that if he substituted exponen tiation AT2 and Bi2 foe multiplication in line 50 the program takes move titan ive Minutes to run and only reports six SUMS Yes Cl there is an explanotion The progiaum runs morv slowly wtth exponents used becouse BASIC s exponentiation rouline ts slower than tts mudtiplication routine The reasne tt only reports six stuns is a combination ef munding dif ferences due lo BASIC s F digit prevision and the fact that you re testing for absolute equality with N Por example the pro gram wouldn t consider 4 001 to be equal fo 4 when for oll practical purposes il ts You can sele lus by performing an Ep silon test of how close the two numbers are rather than for absolute cquality Substitute the following fer line 50 and you ll find that both versions of the prou gram urli ident fy the same 18 sums 50 IF ASSAT 872 t0 lt 001 THEN 80 Diamonds Are Forever Richard Thompson of Santa Ana CA asked us to share his 32K BASIC pro gram with you Ilo uses the LINE com mand for seme spectacular graphic effects You can use Centrol S to stop and resiit the program ag it runs lOCLS 20 COLORO 1 3 22 XW 68 23 YWe68 30 xt I8 XW 40 AH 0 XW 2 SOX 77 Yw2 60 YH 35 YW 2 70C 1 80 FORN IT0100 90 LINEXL35 S7 YH C 100 EINES YH XH 35 C 110 LINEXH
76. Department had humble beginnings with one person working part time in his basement If you were one of the un fortunate few whose computer needed repairs at that time then vou probably remember how slow service could be However that one horse shop has since blassomed into a full fledged service Department Technictans Tim Wilkins and td Segars handle computer repcirs joystick repairs and assembly and cusiom modifica tions for Micro Video s commercial cltents as well as a signiftcant num ber of 32K upgrades In 1982 the upgrades accounted for nearly half the department s work Ha Ha you say that s why Micro Video hasn t offered the 32K upgrade as a do it vourself kit Well as you ll see that s not quite accurate When you dig a little deeper vou find out that the up grade is a considerably more dif ficult procedure than the average Joe or Josephine would want to tackle For instance you d probably not attempt to tune up vour car ef vou have never worked under the rere Wilkins hood before although the mechanic is likely to tell you that a tune up is fairly easy to do The addition of the extra 16K memory involves the rerouting of certain components from the main PC board Also installing the up grade requires more than 40 sepa rate solder connections whtch just adds to the opportunity for an inad veirtent mistake Upgrades can take anywhere from an hour to a day to do Tim
77. Each room is heavily populated however with the spirits of anc trent Roman warriors who resent your presence You can banish them but they return as soon as you leave the room so be prepared to take im mediate action as you venture through the labyrinth Don t stay in any one room too long or sel Mt tract the unwanted attention of the Seeker who guurds the Catacomb ruins a os 5 a a i i a a y F Tp o e i i a a x ie a j i i i Irs 1 fa L a j a Js 4 o k G S x l m x Pt fa i 7 7 A ry L K g s se L f I a 7 i a z E d 1 i i j r s F 2 o es F z J s s i a b 3 5 a a be 5 e l p m 4 gt l a ig Eis w i J z z 7 a a p g m l C x f a p 2 z a a z 5 amp m ae _ F pa b d 2 2 n e ee i z a 2 i m ee Some areas of the maze are locked so to make it thiwugh all 201 rooms youll have to tind the keys that fit the locks Even if you find all three treasures your troubles aren t over You must then fight your way back te the entrance to escape Whether or not you ll like Catacombs will largely depend on your own preference for games Per sonally my taste runs to slower paced games I tend to crack under pressure panic and get sapped in the ether sort This game definitely calls for quick reactions as well as the See eee EEREEEEs B 88s ER H0NE E E g E iF a E
78. Electronics The Computer Dactar does not prescribe replacing the main PC board for every failure Instead tt takes you through Interact repairs from simple to complex An easy to use svmp toms chart provides quick reference to the preser iption to cure your cem puter s ills The Common Colds sec lion reviews repairs that can ee made with a few tools you probably have on hand In the more advanced Major Surgery section I tell you how to treuble shuot vour unit for more complex ailments with wave form diagiams and clear redrawn up to date schematics So take vour doctor s advice Dent waste more Ume and money letung someone else repair your computer Fearn how to take care ofit yourself Bring the Computer Doctor home at only SE4 95 iUs a smart invest ment in your computer s future and Vvour OWN gt Those of vou who bought Mazes and Monsters and dedicated veur selves tu mustering it also reported a few bugs to us In a program of this size and complexity testing all cench liens that c m produce a given failure can be an enormous task Regardless we ve spent time with the program and believe that the problems you ve experienced and repurted are either fixed or can be explained Some usets reported finding the Orb on levels higher than eight That has been ftxed When vou find the Orb and return it te the Castle the game no longer ignores the fact that yeu have the Orb
79. F E GOTO 200 450 REM NORTH 460 IF Y 0 THEN 610 470 Y 1 GOTO 200 480 REM EAST 490 if X 4 THEN 610 500 X X 1 GOTO 200 910 REM SOUTH 520 IF Y 4 THEN 610 930 Y I GOTO 200 540 REM WEST 990 If X 0 HEN 610 560 X X 1 60T0 200 970 REM NEW BUILDING 580 B 6 1 F 8 3 THEN 160 990 GOTO 370 600 REM CAN T GO THAT WAY 610 PRIK CAN T GOTO 200 8 The Computer Doctor Symptoms My computer has an exceptionally loud background hum which sometimes makes real sounds virtually inaudible The screen appears to be slightly out of focus and the text seems to be wavy rather than sharp and straight Diagnosis Sound tank coil may be out of alignment Rx Sound Tank Alignment Aligning the sound tank is a simple procedure that is very similar to performing a tape head alignment You ll need only a screwdriver and a small non metallic hex tool There is an adjustable coil in the RF section of the Interact called the sound tank coil The sound tank cir cuitry is connected to an input pin 15 of the RF chip When the oil is not adjusted properly one or both of the symptoms above classically occur To cure this ailment you ll need to remove the six screws that hold the top plastic housing to the bottom Then lift the top of the computer up slightly and ull it back toward you leave the power and keyboard lines plugged in as your computer must be on to perform this adjustment You won t have to pull
80. Hole adventure is a wonderful fascinating Dut FRUSTRATING game Sometimes i need a lile hini 1o help me solve part of the puzzle but semling a leter to Micro Video each time is a real puin Agreed Answering those letters was more than Micro Video ex pected too The Frol Hole has been a big seller and the mass of mail asking for hints has been heavy Sometimes tt took quite a while toget answers back to you and apologies for that But no more A Troi Hole Hint Sheet is now available Hints are provided for al Most any question you might have but are given in a way that getting one wont ruin the rest of the puzzle for you by eiving away other secrets To get a hint sheet send a A S E and request a hint sheet or request that one be included with your next order fe MICRO g VIDEO PO Bax 7397 XN E Washington St Ann Arbor MI 48104 SSL ELM SI VERINA ai 579599 Coprrighi 982 Micro Video Corporation All rights reserved SMALL BYTES At long last the Small Bytes Contest draws to a close Flere are the final entries Front Rickard Bandalier in soggy Ft Wayne Indiana a Level If program that creates a very strange screen display 10 PRINT CHAS 8 GOTO 10 Aashish Deshpande of Faraungion Hills MI sent in this litte program which he calls Death of un I eeN e gama 10 CLS COLOR 6 4 3 OUTPUT TM LOSING 31 55 2 0UTPUT POWER 31 47 2 20 FORX 1T0100 FORY 1T05 TONEX X NEXTY NEXTX J3
81. It is justly an nounced and the game ends to 3 A Thief sometimes said Gotcha when vou hud nothing he could get They wont do that anymore 4 Sometimes when vou restarted the game after being killed the screen went blank and nothing happened This is one of those random glitches that s tough to Great Keyboard Response Not Carpre the new professional kevboard was the hot item in our Winter E catalog Your response to the availability ofthis long awaited upgrade was enormous Causing an aimost immediate order backlog during our busiest time of year And of coui e wedidntre ceive all the keyboards at once Of the first three shipments we got all keybuards were packed and sent the very next day We now have keyboards in stock how ever for immediate delivery reproduce but I believe it is fixed on the newer verstons of the tape gt Dwarves can now be Pelv morphed Occasionally in the old version vou got the Pely merph message but no racial change occured if you were play ing as a Dwarf 6 A couple of users told us about having a Mawed maze cone way doors cle in sections after load ing in a saved game This is not a program hug but a bad tape save advise that vau always save veur rame twice and on separate tapes lo ensure successful reloading A few people have reported some strange things that oeur inconsis tently like finding the Castle en trance on leve
82. M Pages to spend your money on it ow take the next step and care enough to GET INVOLVED Work with us to make RAM Pages trul your ee generis Share your knowl edge and experience with other members of the Interact community Got hints you think might help other owners Send them to be published in the Tidbits column Put a notice on the Bulletin Bourd if you want to con tact other Interactophiles We wel come article submissions so pick up your pen if youte so inclined Would 2 ar a a a T a Fis a ya SA Si pi j br rE es eet ki 7 a r ba EB B H fay Ta AER eon e H f Fa ha b d ad 1 a Fi ah p Tis reak a oe E H a ie ie ee i Ga iz a L fa oe ae Tr F ym J ian limi i Siu fs vatn ce a i ee a R Deu mr T F EPET I F your application interest other own ers Tell us about it Don Stockton did and that s how the Computerized Corvette article in this issue came into being And of course thete s al ways the Feedback column for voic ing your opinions Every Vote Counts Or Does it Naturally positive feedback is a lot more fun than negative but we welcome your criticisms as wel as your commendations Without it we have no barometer to measure our success in providing you Service and SERBET d like to offer a few guidelines about complaints however You may find these useful not only in dealing with us but other companies wrth whom you re dissatisfied You re more likely to get the r
83. Micro Video started producing tapes the number of titles in che library has doubled Ever wonder why and how a program get co that library Weill 1 did so I asked Dave Ross President of Micro Video Dace where do the ideas for your programs come from Ideas come from mary sources Some programs like EZEDIT weresraeced act Ineeract before it went out of business and Micro Video finished them Some like Earth Outposr are patterned after popular arcade games In this case it s a space wer type game Som like STAR TRACK or our new Troll Hole Adventure were inspired by games popular on other larger computer SyXcms The best source however is user requests The MONITOR for exacople was developed because many people asked to have machine language access Whaee s she next step after you get an idea Evaluation All program ideas and finished pro grams submitted by out side programmers must meet certain criteria Does it tineo the lidiary Ther is do we already havesome thing like it and doesiradd balance to one the various categories Does it have broad appeal Programs take expensive time to produce and each Must pay its own way The successful program takes advantage of the Interace s strong pointes Good use of color sound and graphics if indicated ls imperative And of course if must be a goed game ot useful piece of software or we tun the risk of souring owner so
84. P VP 1410 FOS OfEN1220 1420 ROTH 5 59 1430 IOVI OTHENOW 1444 GOIOIZ20 Chuck s program uses a DEF FN statement in line 100 te calculate the Z ceerdinate of the FiX Y function The variables arc commen mathematical symhels for 3 D graphing theta is the counter cleckwire horizontal angle in radians at which the viewing point is le ented phi is the vertical angle rho is the distance frem the viewing point te the origin 0 0 0 and dss the distance from the viewing point to the prejyection screen He calculates screen points using similar triangle formulas He has suggested several other func tons to t y that y ud interesting p lets Change line 100 to one of the bllowing 100 DEF N 200 SINK Y 100 DEF FN ZIX 4 SHUN X Y Y OX 2 Y Y 100 DEF IN 2 Q COSIX 100 B amp F FN Z A SIN X COSY CHARACTER SPLATTER Programmer Bob Fett Dearborn Heights M 10 WeO PRRE URS ASCOLORO 2 4 20 W INFERNO 3 2A INTIRNO 255 1F A lt WRAS 2551 1EN20 22 B UTIRN DK 255 1FB lt IORB gt 25STHEN2 2 24 C UITTRNGI 255 FC lt IOAC gt 255THEN24 26 FORY 78100CTEP SFORX TON2STEPS W We1 OUTPUTTHES AY XY 28 OUTPUT ORIBIL 2 OUTPUTICHEGIC X 3 COLORO WiiW 2W4 4 30 F gt NEW 0 30 PL OIS6 R SHUT 2 384 R COS T 21 C NEXT C C LIFC gt STHENC ml 32 NEXY COLORO 4 L2 FORT T050 NEXT COLORO 2 4 FORT ITOS0 NEXT 34 COLOROL 2 4 FORT 1104 001032 32 NEXT EXT GOWA That s ait f
85. Pin 13 then aclder the other end to the center post on the back of the switch Solder the remaining two unit That s why it doesn t mean much to publish repair prices Ed and Tim are alwavs happy to talk with vouon the telephone abeut your Interact frustrations In fact thes encourage you to call before sending the computer in or giving up on it all together It may be as simple as a tape head or sound tank alignment or a matter of pulling out one RAM chip and putting in another Tim says And if they want an estimate they should call us too We are always open for consultation t n m to 5 30 p m Monday through Friday as wires to the other two posts on the switch Then solder the end of one wire te the foil pad located directly in front of Pin 2 Ground on the main PC board and the other to the foil pad in front of Pin 20 5V Replace the 8080 chip and you re ready to run Back of Nfounted Switch Pin 2 I Gruwnd Pin 13 ri Hojd Pie 0 SVI Now with the switch in the Ground position your unit will operate normally Flip it the other direction to stop the action in Stantly and when you re ready move it back to restart the program Wben you re in your fifteenth Galactic Clash battle round and your hand is aching fium clutching the joystick flip the switch for the pause that refreshes on Last issue we complained that no one had entered the Ge
86. S Ay Better Mousetrap continued from Page 14 just a Trace Sani Crijen of Mississauga Ontario devised a simn ple graphics tablet to draw pictures on the screen He con nected two pots to his Joystick ports One pot controls up and down movement and the other controls sideways movement He hooked them together with wood and metal and extended a drawing arm from one of them The artn is used to trace over the pictures that you want to transfer to the screen He then wrote a very simple BASIC program to control the transfer ef the image to the screen 20 Bulk Rate U S Postage PAID Permit No 250 Ann Arbor MI International PLOT The Interact community spans the globe he entry from farthest away came from Manuel Uson of Caracas Ven ezuela He s written a routine that adds extended PLOT capabilities to RS232 BASIC that is interprets five PLOT ceordinates The routine can be incorporated into an RS232 BASIC program or executed independently 10 BESTORE FORM 254663T025499 REAQU POKEM U NEXT POKE30S 33 99 POKE30534 99 20 DATA126 254 44 1940 6 122 50 1 17 75 121 50 115 75 205 123 119 50 114 30 OATA 5 205 123 119 50 113 75 71 123 5 144 218 205 106 254 119 210 205 40 DATA106 50 116 75 243 229 1 113 75 205 162 5 14 3 205 46 6 225 251 201 True Grid Bob Fett of Bearborn Heights Mi says he s got the simplest way to produce a colorful game grid He uses the following one line i
87. S232 BASIC if am going lo expand my computer to 32K y RAM Again why all the BASICS You can still load and run RS232 BASIC on a 32K machine ro execute programs you ve written using the RS232 interpreter or programs such as the Loan Evaluator PRINT A SKETCH and MicroText You may also use the 32K Translator program io convert such programs to run under 32K BASIC conirol then CSA VE the programs to create your own copies for use in the 32K environment You ll understand why both BASICs Vind or Mastercharee exist 1f you know the history RS232 BASIC was developed as an extcn sion to l evel ll BASIC that would allow printer access It has no Fast graphics capabilities because it was developed before Microsoft 8K BASIC 32K BASIC our super interpreter combines all the Features of the other BASICs for 32K cquippcd machines It not only has fast graphics automatic PEEK POKE initialization and RS232 access com mands but also another graphics command LINE Different BASICs for different machine configurations Q4 I have a 32K computer but my Friends stl only have 16K What if wanl lu wrile programs io share with them You woni be able to share your 32K software with them until thev ve got 32K too While you can convert programs written in other BASICs to run with 32K BASIC we have no 4 a a a a mE os mian n mia r e ETE ll FE ina PPR DE ai a E e Ea A LO E i a E EOE i PEE E aS E E ar
88. Ti r A rir iii a Tae EA EE EEES RAPE A vad rks ae i 7 i Mea Erina EA pcan tear 5 Hes aes J lt was Sue Denim s birthday Our plot thickened and then congealed We decided to abduct her and stuff her silly with pizza at Smartee s a new fantasy land restaurant just south of the Border Michigan s that is Located in Toledo Ohio Smartee s is one of hero Videu s commercial clients Smnrtve s is modeled in a sivie similar w the Chuck E Cheese s Pizza Time Theaters Its decor has a firchuuse theme There s a stage show with call mechanical instrument playing animals game rooms a children s area and a special room for adults As well as pizza the menu offers a salad bar subs and sandwiches and ice cream treats And a 16K interact is the basis for their order ready displays It didn t take much to coax Sve into the van The mere promise of feod was enough However we learned later hat we were all inno cent victims of another sinister plot hatched by President Dave Ress He worked on our basic weaknesses that we ure all suckers for a good party But he really wanted us to see the commercial display part of the business in action and this was his insidjvus way of ge tting us le ge on this field trip His fiendish plan was admittedly clever but as you ll see it had one fatal flaw As we exited the van about an hour later we got our first clue that we were there for more than a bir
89. Video moved to larger quarters something they have done twice since as they outgrew previous space Since then the company has done much to make the Interact a real and viable computer forming the nucleus to bring together hardware and sofware talent for the machine Information software and new hardware started bursting forth under Micro Video s di rection Abandoned owners now hada place to call with questrons a source for new products a place to get ser vice Ltke the mythical phoenix the computer rose from the ashes to be come a living EE growing little giant among micros If all this wasn t cnough Micro Video decided to pro duce this newsletter at no charge to keep all you owners better informed and aware of your computer s evsting and new capabilities I m glad 1 was there because was lucky enough to be asked to edkt that newsletter and I ve enjoyed it But centineed on page What are the characteristics of a good game Why are some games played endlessly while others are played only a few times and quickly forgotten You ve no doubt seen and played numerous games on personal computers and in the arcades You probably thought some of them were excellent You ve probably also dropped quarters on a few that were downright disappointing a waste of lime and or money Good games can scil computers consider Atari s Star Raiders for example or can gross millions of dollars in the arcades aC its
90. Volts II a two player strategy game the much requested 32K FZEDIT and other goodies Watch for it in your mailbox a 3 Corvette continued frum page I m unted in the roef of the vehicle and give it an other worldty air when they are flashing Maybe he will in stall an ejector seat next Sit Boy Imagine that you ve just entered the World of Wheels show There sits Don s platinum pet before you ap parently unattended Curious you approach it and the houd opens up When you step forward to take a peek at the engine the radio suddenly begins blaring Startled you move over to look at the interior and with out warning the roof lifts up and back You might well wonder what is going on Well it could be Don a hundred yards away giving voice command to his fiberglass beauty with every move you make He s been experi menting with a Voice Recognizer which will let him literally tell the car what to do next The Voice Rec ognizer hooked to the Interact through a joystick port is pro grammed to recognize Don s voice and certain words which he reiays through a head set lt even informs him when each circuit has been com pleted In essence the Stingray will become obedient like a perfectly train dd g Like everything else we put in the car in theory the Voice Recognizer works su t fine but there is always a lot of trial and erzor with everything 4 new we do Don reports We do all
91. a 32K machine f course just by changing the as sociated text the scenario can be dramatically revised Instead ofoffice buildings you might have multi floored caves populated by bats and trolls or pirate ships filled with cut throat criminals and cannons Add some fighting and scoring routines an object to be retrieved or a damsel in distress to rescue and y eu ll have an entertaining diversion for long winter evenings 1 COLOR 011 37 10 CLS PRINT ONE MOMENT 20 OIM A 2 4 4 4 30 REM PUT IN OESHS ANO P ANTS 40 FOR 8 0 TO 2 50 FOR F 0 TO 4 60 FOR X 8 TO 4 70 FOR Y 0 TO 4 80 2 RNO 90 IF 2 4 THEN R 0 GOTO 120 100 IF 2 lt 7 THEN R 1 G0TO 120 110 R 2 120 AB F XYJ R 130 NEXT NEXT NEXT NEXT 140 CLS 150 REM SET STARTING COORDINATES 160 8 0 170 F 9 X 0 0 I90 REM WALK AROUND IN BUILDINGS 200 PRINT PRINT PRINT BUILDING 8 210 PRINT FLOOR F 220 PRINT X X Y Y 230 PRINT YOU SEE 240 IF A B F X Y 0 THEN PRINT NOTHING GOTO 270 250 IF A B F X 1 TREN PRINT A DESK GOTO 270 260 PRENT A PIANT 270 PRENT PRINT WHICH WAY 280 PRINT N E 5 W U D 290 X eINSTREIIF X THEN 290 300 IF X U THEN 400 310 IF X D THEN 430 320 IF X N THEN 460 330 IF X E THEN 490 340 IF X THEN 520 390 IF X W THEN 950 360 IF X THEN 580 370 GOTO 290 390 REM UP 400 if F 4 THEN 610 410 F F44 GOTO 200 420 REM O WN 430 IF F 0 THEN 610 440 F
92. a format leis players at various skill levels compete without unfair advantage Ww any one player You might vary game time difficulty of play number of chances etc by player Scoring and Rewards How you score your games or re ward Players achievements can be important in how well a game is liked How and when you present a player s score can also add dramatic impact to the game Always keep score in sume foim A game whch offers players no feed back or mesure of progress very quickly becomes dul How yeu score will vary from game type to game ype You ll have to evaluate your game objectives and determine how to express degrees of having met those goals Sconng may de relative to ume elapsed number of moves number of hits or correct responses cic as appropriate to the iadividual game but it absolutely should be included Display the score on the sereen at some poini in the game fn some pro grams you may not wani to show the Leak for fia ae da hr mea rately score at all uct game play has ended In ethers you may want to have the score continuously desplayed and in cremented on the screen In some games tt may be appropriate to have the current score or status of game factors displayed graphically You might for exumple have the number of ships remaining in i space war game displayed visually In a simula tion program you might want to dis play fuel remaining with a graphic paupe rat
93. a tn record format While you might use VideoCalc to examine your sales of products by quarter you might use DREAM to keep inventory records of those same products The record for each product might contain fields in ee fe Te a Te my aaah eper 10 00 PART W apRgE Tho GFF Vv e its POIA m DEV LZ 19S 9991 ea PLP ISl Qh Fan which you describe the product list the supplier keep track of current inventory levels record unit costs etc Like VideoCalc we designed DREAM for flexibility You define the record structure how many ieces of data fields you want to Keep in each record what type of data each field will contain and what each field should be calted for data referencing purposes DREAM then tells you how many records you ll be ableto work with given the defiined format With simple short records DREAM can manage ap proximately 200 records at a time more often sour record siructure will give you a 70 90 record capacity In the DREAM documentatien Petronius Pepper picks the program to help with a porsotan problem keeping up with the consumption of food at his Pet Emporium Petronius shows you how easily DREAM lets you add update delete even sort and reorder the records then view them on the screen or produce a printed report of all or selected parts of the data Whatever your business one or the other of these programs will come in handy In fact you ll proba bly find you can u
94. achine due to differences in VO memory mappe You may be able to tell whether or not your tape is defective by how it loads If your computer won t load the tapes at all check yow tape head alignment If it loads but no gt prompt appears and the program does not respond to the keyboard the tape may be defective or your computer and printer may not be communicating Check your cable connection and make sure your printer is on line Initially there were several bugs in Asc mbl ex Editex In the first ver sion a printer initialization problem slowed output to one character every seven seconds And although you could set the baud rate in Editex As semblex would only run at 1200 bps The programs displayed line num bers greater than 100 improperly and they couldn t write more than 256 bytes of code to tape at a time Qur second version corrected al these bugs and the programs now operate correctly We sent updated copies of the programs to everyone who had received the first faulty version If yeur tape exhibits any of these symptoms perhaps we missed you Give us a call to arrange for a replacement continued on page 15 IS l a Valuable Coupon kee CAAA Offer Expires 10 00 OFF wr Professional Keyboard TA list price 79 95 Your mailing label must Limit 1 Coupon appear on the reverse E Per Order a ee of this ceupon AY Ty TS H el p cwretineceed f mem ge lI Perhaps Assembl
95. adults and children can spend hours with this game Children enjoy see ing how many butterflics they can safely escort to the other side of the screen while adults are stimulated by the challenge of scoring maximum points per trip across Micro Video s President and his 1 year old daughter have given Wing It a real workout Dave abashedly reports that she routinely trounces him when they compete a game Phaser itin our Christmas catalog Ss oe ee a a ee ce What s coming up The Ahero Video Exccutive Controller for the down to husiness Handcrafled in cherry or walnut the controllers features arcade quality joystick and dual fire buttons Watch for Heads Up Pinballis ne ac tion game guaranteed to appeal to all ages The ball motion and joy stick flipper controls are realistic and smoothly responsive You ll swear you can feel the plunger pull back and release to launch the ball into play Clever graphics increase the entertainment value of this non violent action game Finally a dark horse game ou mav have missed in our summer catalog Mega Volts Although the rules are simple your goal ts to draw robots pursuing vou into elec trified fences before they can get to you but it takes some thought to determine the most strategically sound pattern for play Three skill levels let you vary the number of robots and electric fences for easier or harder play Although it started ou
96. age 3 Another command difference is PRINT This is the equivalent of our OUTPUT command Watch this one though because our letters ase a lot bigger than theirs You may have to reword the text that appears on the screen TRS 80 programs use a lot of their special characters CHR You can get a chart of what these look like at your local Radio Shack They ve also been printed in many magazines I vc found that it s diilicult at best to con vert these so Itry to get a look at how i kind Youll also be interested in the article in this issue about the Exmron stringy sponge We hope ta keep vou as an Interact owner for a long time to come M L September 17 1981 Dear Micro First I want to thank you for the newsletter you re publishing Together they have done more for my program ming ability than all the other books and magazines I ve stockpiled in the last year This ol Level Il gets funner all the time From the Editor s remarks in the Fall publication I gather a lot of folks are writing to you and asking for a bunch of freebies People should understand you don t come across with the big corporate image because we are a relatively small community in the nucro market This docsn t mean were old pals and can indulge in swapping that kind of information On the contrary it probably means you need our individual support financial and otherwise more than most other companies in the
97. akini pia aT a aS kiem Te Pha ega ell ll r r a 1 o at v eee e M SS E Er t os SE a N a Tt oo Be e m ee eg E pe b LSS a gt e a 2 a a m 3 a a i Tr rrr 6h oe L tere e ee e a Ra se m DEN PE E E W ail ee cul LS j m i AETI On PU he eg ee Ataris fully planned to subscribe but I was rather upset after the resulis of yeur Better Mousetrap contest came out Very briefly you mentioned terry Wirth s entrv which was the same as mine 1 except I sent pictures and in cluded a cleck timer ptugram to make it useful But not even a notice That s your choice but an explanatton would have been nice rv Woelile Morton IL ear fru Apparceniiy your Better Mousetrap necer reached me i w searched through the files containing ali the entries and could find nothing with your name on it ff yerd like to resend it Pil be happy to in clude ud nert issue in the Tidbits cevumn Dear Micro Video In yo r editorial last iue you stated that the siae of RAM Pages in number of pages was centinuing to grow but that does not mean that ihe quantity of useful infurmalion passed along to the reader has increased You now are chargirs S 20 year or S3 issue yet this issue of 20 pages has only 5 pages of useful infor mation and many pictures If you con tinue to charge L poge of information
98. al puess to what vou look Hke wins something neat like a emne something Here s biti al vou Kel Barry Blur Cod Paws Alaska Dear Buri Nat a bad idea the picture I mean T doubt if any of you could guess what look fike Sue Dentin Dear Editor sust thought I would drop you a note to commen bath Jiero Video and RAM Paves on them support af my campuicr I was once ashamed to sav owned an Interact Everyone would sav A What It was really embarrassing te say that the cempany went oul of busi ness and there were enly 1000 or so in North America Lo and behold Micro Videe arrited on the scene and previded me with great software a memory cx pansion WOW and now a keyboard Now when people ask me what type of computer own tell them with pride When they say they never heard of it 1 tell them it s an exclusive elub Alex Kazim louston Fexas Pear ditor Rush me vour latest catalog which has the SI NO off coupon for ihe new kievimard tor che Interaci Model R My wife tore if up and hid the pieces Yours sincerely Bert Cooper Housten Texas Iwar Bert Aape var keep veur computer and japes vineter Cock amp kex Sue Denim Dear Editor Thank vou for sending me veur spring SZ eclition of vurr RANI Pages would appreciate any more information on Interact computers For sabe Apparently the Interact computer purchased From Protecto Enterprises went on the blink This was my second on
99. ame and a word processing program with true text handling capabilities Double Trouble What gives this two player game a special twist is that the players do not battle cach other Quite the re verse in fact Both must cooperate or neither wins The objective is simple toclear the game board of all the nieces But there are two different kinds of pieces and each piayer can pick up only one type There are also separate rules for each player s movement which can only be over ridden through combined strategy There is of course an adversary but it is the computer which controls an arachnid like monster that chases whichever player is closest The game has four skill levels and nine speed settings at each level so play can be as slow and methodical or frantic and frenzied as you like Naturally we were able to win more often at slower speeds where there is definitely more control and working together is easter However at faster speeds we had mose fun We d end up laughing 30 hard it was nearly im possible to concentrate on our strategy think parents will appiove of and enjoy this new approach to gaming which teaches cooperation rather than confrontation Catacombs A single player game Catacombs combines very fast action with the appeal of an adventure game The game takes place in you gnessed it the Catacombs a maze of 201 rooms Your objective is to find the three lost treasures hidden there
100. ange center on your TV turn the tint control all the way lelt then all the way right At one end ef the range the background celer en the ecreen will be blue at the ether it sheuld appear red if there is ne sig nificant color change the brightness er color setting may be too intense The center of the range is the point at which the background color changes from red toblue Now turn yeur cemputer en and eff several times and leek fer differences in the visual appearance ef the DEPRESS L TO LOAD TAPE message When your machine wakes up in goed spirts the white color in the Whar side af the turd did sour computer Rel if an this moming DEPRESS lettering will have a slight reddish cast while the L TO LOAD TAPE line will have a bluish tinge This celor difference in the text occurs because the two lines start on different even odd pixel lo cations on the screen If on the other hand you cemputer wakes up with a negative outlook you ll see a rever salin the lettering tints the DE PRESS line will have a blue tint and the L TO LOAD line will ap pear slightly red The technical ex planation for this phenomenon is rather complex but you hardware enthusiasts may be interested in knewing that it has to de with the phase relationship between the coler urst IC20 and the first stage of the timing chain IC16 Although your computer s mood won t otherwise affect program op
101. ar Friends Fist would like te give You mv as sessment of the new keyboard In enc word t s excellent hwy bouatce prob lerns clearest up aiso t is no longer a prebjem to enter a Jong program Sincerely Wal Meere Pittsburg CA 2 19 MICRO g VIDEO 305 North First St P O Box 7357 Ann Arbor M1 48107 313 96 0626 Program Notes continued fren pege 3 like me prefer Pack Wars for all the reasons mentioned above It ali depends on your taste Communicator Pius So much f fun and games Now on to more 2eriotis stuff Our Communica ter Pius was developed simply be cause many of you have asked for its capabilities It takes up where the old Communicator left off Now you can communicate with another computer or system 1 e The Source ComNet or even another enterprising Interact owner and keep a permanent record of the event With the old Communicator all you have is the screen display You either have to write quickly or be able to eei a lot The Communicator Plus can pull the information off another system and store it n a buffer in the nteract s memory This gives you two options You can unhook your modem connect your hne printer and print the stored information or you might try a simple switch such as the one described in Hardware Hints RAM Pages Spring 1982 Your other option is to store the inf ormat on eee pe for printing at another time THE COMP TING DIS YOURS INTERACT OWNER
102. ass these parameters to BYTPIC with the fullowing series of Instructions MV B 02H MVE C 07H IXI 430H LXI H FACE address of picture CALL BYTPIC This code act e the size uf the pic ture 2 bytes by 7 lines in the B and C registers and tells BYTPIC to output the picture un the screen at address 4304H Notice that in this example we have not identified the address of the picture table called FACE You can put the table anywhere you like in memory but remember to define FACE as an addressed label before you call it via BYTPIC or another routine The chief disadvantage with using BYTPIC for graphic animation is that because 1t is byte urlented yuu cannot move the picture less than une byte ur four pixels at a time The result is motion that tends tu be a little Jerky See for yourself with the folluwing routine LXI D 4304H MIVFACE PUSH D ViVi B 02H NIVI C OTH XI HEACH CALL BYTPIC POP D INX pD MYI A IGH CMP DF ANZ NIVE ACHE Yuu ll notice une other problem with this routine the picture leaves a trail as it moves acruss the screen That s the fault of our picture table though not the ruutine itself Next issue we ll shuw you huw tu change the picture table and cover vour trail You ll also find out how to get the flicker out with PIXPIC our pixel oriented Muve routine Stay tuned gt A Message from Your Doctor Why You Should Buy My Book The s i LJ
103. ave anything more than Inveract so fer as I m concerned For a while l thought I must be the on ly Interact owner in the world Your newsleceet and Interact info are like letters fom a ee friend 1 just een t get enough of them And I d be pleased to tell everybody how good your machine is Just have em wiite or call Gary Sard Carthage MO WIPEOUT A number of owners have encountered the infamous bug in Level Il BASIC that can cause the loss of an entre program The symptom you ll experience with rhis bug is chat when you try run your pro gram the TV sczeen fille with a character pattern and all of RAM is wiped clean This problem can oecur if you reference a non initalized string variable either threugh a logic error or a mistyping of a sting variable name Thete s nothing more frustrating than e lose an entre evening s progress to a single keystroke er ror lf you recognize the symptomand hit reset before the screen is filled jou can usually save the program If you use the olde Level II BASIC you should take ex fra precautions when working with strings such as frequent CSAVEs befeze testing changes or additions with the RUN command The bug has been fixed in both Microsof 8K and the new 32K BASIC a ur requests have once again been noted To really te able to utilize the capabilitics of our computer we felt we needed mass storage i e disk While Micro Video was aware of this there were in
104. bat n a continued or page 20 19 Contests MICRO G3 VIDEO 305 North First St P O Box 7357 Ann Arbor MI 48107 1313 996 0626 Survey continued from page 19 Please iall us how yOu teel about the ovevall focus of RAM Pages and Ihe amouras ot Space Gedicaled to the following areas Too Just Tee Little Righi Much Hardware 2 3 4 5 BASIC Programming l 2 3 4 J Machine Assembly tanguage l 2 3 5 Product Information 2 J 4 5 Conk sts l 2 3 5 User Inkirination Exphange l 2 3 5 Interad App calions l 2 3 5 Program Listings l 2 3 d Uses Feedhock l 2 3 4 5 EStowul i 2 3 d Please ank your miest on teng the bhiorng NO of ares or renldy alaa otm eorrnuwed in RAM Pages ae m ry Interested Interested BANC Fiogramming Machine Atsembty Language Hardware Movificalion Repay Intevacl Apphical rons Product feviews Updates Feeddach from Mher Users Information Exchange Discount Coupons EE SS ES SS SS FS he RM M HR BH amp M KH N FG t y w U Ww Ww Ww WwW ce gt a B amp B h gt A A A Ex wv N n N am N N Qn Are thee olher areas nol mecluded in the above hst thal you would bie fo see covered in general how wows vou Gescnde RAM Pages articles in terms of how weil or much you kam fromthe Teo Emenn D gt 2 3 S lt a loe Technical In general tow well does RAM Papes met your needs in leems of its content Met Relevant D 2 3 ag vey Relevant FIRST CLASS Fi Pa i
105. been cor rected by their owners Secondly you ll reduce the time your computer mgt TIN TH ri TOE head ts then exposed and you can re selder the connection The second case in which one or more of the six wires en the read write contact switch ave breken or nose can create serious problems Sot only can this condition prevent successful loading but ila read wire and a write wire accidentatly come into contact your tape may be erased as you try to load the program 2 The answer here is also soldering but because the wires on the read write contact are close together the operation can be tricky Unless vouve got a fine tipped seuelderiny iven a steady hand and experience doing this sert of thing jon c commend you try tt Broken wires can cause a variety of operational problems from a loss of power tu strange patterns on the screen Many of the wire conticts are fragile soif yeure m and out of Your computer a lot vou muy encounter difficulties related to wires connected to the RESET huiton the ON OFF switch the keyboard the tape drive Dont panic Just open yuur unit back up agam and check vour con Ne clions Thanks again David for sending us vourc mpl M is out of service since yeu wont lese days in shipping it back and forth Finally youll learn more about your We computer and how it works Unlike the old service manual adapted From the one originally pro duced by Interact
106. c display of the checkerboard and pieces be more allunng Simula tion cames like a luni lander should have graphies that visually relate player decisions to performance Watching your space crifil crash into a planet because you used too little thrust has fur more impact if you ll pasdon the pun than seeing a text message that tells you you ve crash landed Graphics should always be appropnate and it into the scenario of the game however Graphics for the sake of graphics only it inappropr ate may achieve an undesired e f ect Animate Your graphics when you can Make the dice roll the slot machine wheels spin the playing cards snap down on the table the propcllar blades on a helicopter whirl as it Mies etc Cute related graphics never detract from a player s enjoy ment of the game Use sonne cffects if the computer has the capability to create them Sounds can add realism to the game the roar of a car engine the blast of a laser Sounds can also be used as prompts to acknowledge player moves or as warning s in the game Sound if used should be cute rele vant variable and most importantly non irritating over long periods of time Cofor is a useful tool for adding vanety aad visual appeal to a game Color can be useful in identifying players or teams changes in game modules special game status etc Simple color rolls blinking or screen Mashing can add dramatic Nair to any game Select
107. catch The unit isnt very smart when it comes t nonstandard rules of pronuriciation of which there are many in the English language While most words will sound just fine the wayi they are notmally spelled sometimes you have to spell phonetically that s the way I always spell just ask Cori who has to edit copy the word H would have to be spelled W gt For example GLISH to get the proper pronunciation This is really a very small drawhack however as YOu can correct and test as fast as you can type The T N T also has ing nits phonemes i your Interact speak saa wen Or make ee zy provisions for accessin directly so yourcan ma Sour lary of nouns and verbs hat you can use to move around in the erwvironment and manipulas objects you find to solve the puzzle Part of the fm and challenge of che game is discovering what words the computer understands I dont want give away pars of the Troll Hole puzzle se lex me illustrate the idea with an imaginary example Ar the p of the screen you d see your location fex example A DARK DUNGEON Below the location is a list of the obvieus ditections to exits NSE W Then the computer tells you what it sees A SKULL A CHAIN A BOWL OF LI OQUIID and asks you what to do You might type a direction and go on to ex plore other areas You might type PULL CHAIN and disc
108. cerely Larey Bond Pheenix AZ Larry Yotre on yui list mento Damn Sue Demim Dear Miwa Videu l have just trstall d your new keyboard and the resul tS are truly out standing have owned mv Inacract Sor three years and this is the fast time can henesthy sav that really enjoy pro frumtming You deserve a hearty Well Dene with best wishes for vour con tinued success Sincetely S E Novotny Jr Hazleton PA Dear Mero Video Yar fall 962 RAM Pages was greail My tape drive irad become vory noisy wied the cure mentioned in the articte Compator Dorte fer ootrecting a bad gmund und it worked The tape drive has never been s guiet It gow reads all my tapes lhe First ime with ne prablems Thanks for che vure Ser the tape drive ilis Also l wondered why sometinaes the ann display was not as gwod as other times Your Wake up Call explained it correctly I now watch my Interacts mood swings and enjo vit much more H i E I Barrie eee ee een ee Pe eee Se ee eee eee TEZY L i lt m oe eat a i a pe a ae ae T B s a es 2 ia Bee ees ee aa RAL Sur ee alle a ma maia ee a B Pa os E oo 1 D i i ap a f 3 ry fe Keep up thes good work Now if vou could only tell me how to get vid of the hunt in the sound Albert Tarseh North Tuntington PA Deer Albert Sounds like you need a sourd lank altgnment De you hace t
109. checking that the values fall within the limits of the screen He s come up with an ef ficient scheme for handling these functions which you can incorporate into your BASIC program code 10 PLOT X 1 J JOY 0 IF J 0 THEN 10 20 PLOT X Y 0 X X JAND1 ANO X gt 1 JAND2 2 AND X lt 110 30 Y Y JAND8 8 AND Y gt 1 JAND4 4 A ND Y lt 76 GOTO 10 Password Please Don Dawson of Park Forest Illinois puts password protection on his top secret programs with the following routine 1 CLS 2 COLORA 7 0 0 0 3 PARINI A PASSWORD tS NEEDED TO USE THIS 5 A INSTAS 2 0 IF A two letters of your choice GOTO 20 1 PRINT YOU ARE NOT PERMITTED TO USE THIS 12 FOR P 1 TO 480 NEXT 13 COLOR 7 7 7 7 ENO 20 PRINT titte of subject matter Feedback Dear Micro Video Your equipment is a good intro duction to computers my 6 year old and l4 year old love it and my 7 and ll year olds enjoy it I m getting tired of seeing OM errors though look forward to R M BASIC sc we can get it and the 32K for more power It does seem slow on some programs We also would be in terested in FORTH and PASCAL Robert Slaughter Milan Michigan Dear Robert BASIC does some things well but i is slower in some areas than machtirre ranguage especially in graphics motion KOM BASIC won l solve this You an effectively in crease your programming space and reduce M eriors by employin pra ram compac
110. cities randomly plocted on the bottom of the screen from destrucion by invading missiles Hovern abore the cides 3s your cucast station which you ean move via che joy ick from side eo side 28 well as up and down aomething different You position the station beneath the falling bombs and Press the fire button to shoet them down There are two types of missiles in che eame The regula missiles must score a direct hit on one of the cities eo destroy it and end the game but watch our amp che supe rocke With those close counes You alsotry co avoid your station being hit by missijes While a colli sion with a missile destroys the missile it also damages your space station and slows your ability to move You score points for deflected Wombs based on the Pe of bomb and the aktitude from which you fse at them As che me Progtesses che of invading missiles incteases nr til ic becomes difficult eo check them all 1f you re good enough your cities will sur vive the intense Mvasion and the number of missiles will ebb giving you a lictle breather befere che next wave srar s High scores of over 30 000 take more than an hour to achieve Can you do ir THE TROLL HOLE ADVENTURE 1 player or group Adventure is a game born of cem puters There are many different scenatios for Adventure games but all are simula rion Puztles in a narradve form Typically they all work in precy much the same way You are placed in an envi
111. citing superfast war of nerves and the ulti male test of your reflexes Ships ap pear randomly on the four sides of the screen and shoot missiles at you You must aim and fire back before the mis siles htt your space station The better you get the faster they come It s fast and furious insanity for kids of all ges f can safey recommend all of these games Each ts like having an arcade in your home I figure that at 25 cents a game I ve paid for one in a single evening s play Now on to more serious programs but ones that arc just as exciting to us computer nuts Fhe programming aid most asked for in the surveys an Assemblei Editor has arrived on the scene For those of you who don t under stand the purpose of an assembler a brief summary An assembjer editor combination provides an easier way of writing machine Janguage than o Hardware Hints Printer Modem Switch This issue s Hardware Hints pro vides a reasonable soiution to the problem of trying to run a printer anda modem simultaneousty This informe tiem was provided by ny good fhend Russ Patien Many of our readers have asked f it was possible to run a modem and a printer at the same time from the RS 3 pon Fhe answer has been no at least up until now Check out the ar ticle on the Exatron Stringy Sponge and dual port option in this issue Ad ditional software will be required to use the dua port option with a printer and modem so in
112. color combinitions for your display which arc not tiring to the eye even after hours of play Dark backgrounds black or blue with brightly colured foreground objects usually work out best The game should also though be playable on a black and white screen What constitucs a good game ts of course highly subjective What bores one person to teas may be another s passion And to each of these guidelines there is undoubtedly a counter example of a good game that Violates the tule However few really goed games violate very many Prob ably the most objective way to evaluate a game s success or failure potential is to sec how often it s played Try your games out on your friends and find out If they enjoy it they Il want to play again and again and again i Interact Survi ves 4 Nuclear K Blasts Puul B Anderson of Norfolk VA supplied this story ahnut an lateract that Jotaedthy Navy knew my computer was SF ane longh machins Sve niiclear blasts 5 Simulated ones of course The U S S Kidd DDG 993 and an Inter acl computer recently completed blast tesis al a special range in the Carib bean Three tests were conducted one with 0 000 pounds of TNT and two others with 40 000 pounds Each bias was subsurface and l were at canges of less than 1 000 feet The ljargesticlosest blast was tre mendous The above mentioned bulk head moved in about a half an inch The space ilself actually rece
113. cores simply because of an ability to hit the fire button at a faster rate than other players Give players bonus scaring opper tunities in the game Let players exhibit morc skill to gain higher scores more turns or increased pame time Award mystery prizes for especially high scores or achievements These may take the form of bonuses or spe cial animations graphic effects or general fanfare Special prizes should be awarded only for cxceptienal per formance Thus they may be visible in only a very smal percentage of the games played Graphics and Animation Color graphics and motion can be very important elements in mitntain ing player interest Let s face it games that ure purely text display tend to be dull While the use of color and sound can alleviate some of the textwal tedium graphics and anima trons wall almost always make the program more entertaining Whenever you can use graphic representations of the clements in your game If your game involves rolling dice show the dice on the screen graphically use white blocks with black dots inside rather than using standard numeric representation If its a card pame display the cards with suits and vulues on the screen Games that feature creative graphic display will invariably evoke more player enthusiasm imd response than equivalent games without graphics Who wants to play checkers as a senes of coded moves Wouldn t a giaphi
114. cutes fastet That s because ie only has to go to line 20 to find the subsoutin The final score on the screen shows you the elapsed time The first program takes almost 4 seconds to run in the second the time has been cut by almost half a second Apply this idea to action type progtams and you ll find a significant difference In how fast yout programs tun In Jarg progiams particularly this technique an cut minutes aff execution time 10 CLS 20 REM POOR PROGRAM 30 POKE24559 0 40 POKE24566 0 50 FORX ITO600 60 GOSUB 110 7ONEXTX 80 PRINT PEEK 245501 90 PRINT PEEK 24559 100 END 110 REM 120 RETURN 10 GOTO100 20 REM 0 RETURN 40 FORX 179600 50 GOSUB 20 60 NEXTX 7o PRINT Pees 90 END 100 CLS 110 REM BETTER PROGRAM 120 POKE 24559 0 120 POKE 24560 0 140 GOTO 40 Jn the programs above we us d the In teract s ineernal clock Many of you have asked for ways to time things At address 24559 the clock suns at approximately 1 60rh second intervals It uns from 0 to 259 Address 24560 is the overilow each rime the clock hires 256 it updates rhe value in address 74560 and resees 24559 to zero In che above examples we POKEd actos in both addr sses co seart fresh There are more accurate ways to use the clock bue for time comparisons or a notmal timing fonccion fs in a Quiz ot game see REAL TIME QUIZA this method is a usefu esol Real Time Quiz dow do you writea quiz progam that has time l
115. dir i sions unless each of the subscript s kept small Even with small sub scripts however memory consumn tion may be a preblem Consider the statement DIM A 3 3 3 3 3 which creates a 4x4x4x4x4 array that contains 1 024 elements Each element always consumes 4 bytes of memory so this array would use 4 096 bytes of RAM That doesn t leave much room for program code to use the array mandate ina 16K sys tem which only allocates 4 698 bytes to begin with It Is even memory consuming in a 32K system This isn t to say that multi dimensional arrays cannot be used on the Interact They do however have to be dimensioned as efficiently as possible To wit we ve devised a sim ple program that illustrates how you 10 might use a multi dimensional array in a game The program uses an array with four dimensions to create the rudiments of an adventure style pama The program hasn t been fully eveloped into a game so you wen t find it terribly exciting to play but it does demonstrate the potential value of an array with several subscripts You may wish to continue develop ment to make a true game out of the concept In program line 20 the DIM statement sets up the array that acts as the game board QIM A 2 4 4 4 Although you could assign any scenario you wish to the game we have chosen to have this array repre sent three office buildings each five stories high with each floor a 5x5 grid In the DIM stat
116. e both written in Microsoft BASIC for 32K so you can modify them for your own specialized application needs The two questions most asked about these two programs are II What kind of programs are they and 2 What can I do with them With those questions in mind let s take a closer look at both programs VideoCale VideoCale ts Micro Video s answer to VisiCalc a popular data model ling program availiable for many computers A program like Video Cale has a multitude of uses in fact it was designed with just that flexi bility in mind Although many other uses are possible VideoCale is most com monly used to manage and analyze time series data What s time series data Bricfly a time series is any group of data for which values are recorded at specific periodic in tervals such as weeks months quarters or years You might for example use VideoCalc to track sales of preducts by month or to analyze the productivity of your sules force on a quarterly basis Es sentially any set of numeric infor mation that can logically be organized into a Ladle or matrix format is a serious candidate for VidcoCale processing a Once you ve decided what data to work with you enter it into the VideoCalc matrix the size of which you define to meet your application requirements Unlike VisiCale which has fixed row and column names VideoCalc lets you assign names to the matrix that descri your data The assigned names a
117. e 8023A we lave used it is werth the price Radio Shack Printers We have no direct experyence with Radio Shack printers all the follow ing information was obtained by none conversation with dealers and feedback from owners who bave them Based on that here s what s available in serial printers from Radio Shack For 399 or under you can pick up an old BMP 500 although dealers usually don t recommend t It is slow ovdinued on page 9 D For advanced programmers only When we left you last issue wed just described using BYTPIC to put a icture on the screen and move it he result was generally unsatisfac ory though The motion was jerky and the rate left a trail behind it as it moved This time around we ll show you how to clean up your action and how to use PIXPIC our pixel oriented move routine to put smooth and flicker iree animation into your programs Covering Your Trail As you ll recall we were working with the following picture and color set With the BYTPIC routine we out put the image on the screen four separate times each time shifted one byte fowr pixels to the right How ever we didn t include any means of erasing each image before redisplay ing it at the new location so part of each picture the leftmost byte remains on the screen There are several potential solu tions to this problem You might call the ROM 1voutine CLS to erase the screen before plotting
118. e FASTER BASIC arricle m Hardware Happenings Eyes to the World The Interact Gan re what s going on acound ir Yes chats crue it responds to aape resex k d and entectanment eranle inputs The next logiaal xep is e harness this ability eo accept input for ou ownuses The joystick port is one of the best ways to talk co ourlnterace t has four swivch inpue for che joystick and three analog inpow pot fite and spare Lers examine using one of these in a very hyndamental way Ihe pot input measures a resistance Any cesistance device within the proper parameters can be sampled though BASIC Changes can be measuted and subsequently aceed upon I bought a photoresistor 276116 1 19 from adio Shack and attached the lends to pins 5 and 7 of the left joystck port to give my interact eyes JOYSTICK PORT Try following 10 CLS 20 COLOR 3 0 0 7 30 PRINT GOOD MORNING 40 PRINT PRINT PRINT SOL POTO 6 IF L gt 0 THEN GOTO 30 70 GOTO 90 80 CLSCOLOR 00 07 95 OUTPUT GOOD NIGHT 1535 3 0 L POT 119 IF L lt 90 THEN GOTO 10 120 GOTO 100 When you run this program with th light cell attached the compurer ean cell if the room is in light or in dark So what So a gear deal Think about all the othe things you might do with a lighe cell How about a carbon resisrance mike Many thermostats work with resistance Now thae your In teract can see heat and feel the world shar can you do w
119. e From them Tow bad I didat know vou fotks earlier sincerely B Takaki Honolulu Hl 16 oe ae iy n gai inl HH wane Bs pet ains ie el a n ai P bmi dee et egy Kee Re Ee ast r eH he Beat H PA ree ae a pa ao i i a Eea Pa ma a e peo tly s e 7 oe i i rs ee E ETIDE Deor amp Before vou decide ta buy vet another machine gice Tim a call see Repair story poge 10 lu see yours can be steed We can get most computers ap and raning ogain Tiit is totally shol see the Interoects Fur Sale story on page 15 Dere belitor My son has had his Interact computer now for a few vears and he not only en joys M for its games but has utilized its versatility as an educational aid Prior to obtaining hisi awn Interact computer he was Introduced to computers in his Pro ject Potential fass ia program for academically gifted children tn the pub lie school system Since thal introduc tion he has developed his programming skills and furthered his education suh atantially 1 fel that the Interactcoutnru ler helped make at least a partofail this possible A concerned parent Livery L Burgener Phoenix AZ Dear Mien Video The followtng are some passing tiinughts l Lave the machine 2 Greacly appreciate Lhe RAM Pages like a letter From a friend a a 7 Fi Bi m am m T SES Lr se mm oon s u 2 ea a a i T aS Ea fot mae UF f e ee as Tors SS ae a ee eee l a e
120. e a ee eer F oF L Pa PEA 2 7 Sy 3 Fnrmat of RAY Pages is guad would Itke to see them become even more mformative 4 Feel more confident m Miero Video after learning of your continuing and expanding support fer the unit lUs nice to know I don t own an Eese bean for he Junk vard Thanks Jor all your efferts Is the unit still being manulactured How much does a aew unit cyst Will there ever be a antt made idif Form model that uses a disk drive Peter Klemish wh Gal Gi Dot Peter 1 Thanks 2 Fhonks again 3 Thanks again again a were Eng Any ypecifie suggestions f Gouet L Yare telon 6 Yes 7 See pawe 15 8 Probably net for reasons discussed in pasl USSUCS Gentlepersans A couple of years ago a very good friend purchased an Interact and contirrucd on Pose 9 SEmi Here s your chance to interact with other owners ab solutely frec pestage paper and envelopes excluded in our new Bulletin Board section of RAM Pages You can think of the Bulletin Board as the want ad section of RAM Pages The only catch is that you have to bea RAM Pages subscriberto take pait Asl mentioned in Remarks you can use the Bulletin Board to ask for or volunteer a variety of information However forour sanity we ask that you foilow a few rules when you send your message to be pe sted Use 25 words or less D fhe words Bulletin Baar Should be written on
121. e correction of reported Assemblex Editcx bugs Fach fix sceme d to grencrate more bugs So rather than buying stock in a phar maceutical compnny we ve decided to scrap Assemblex Editex But dont Worry We wouldn t leave you im the lurch assemblcrless Allow me to introduce AL our new assembly language programmer AL completely replaces the Assemblex Editex dynamic duo Better vet AL has more power depth and fiexrbil ity Hes an cditor assembler end monitor wrapped up in onc petite package Compatible with both 16K and 32K RAM machines AL oc cupies only 4K of RAM inaddition to the conventional de cimat and hexadecimal numbering systems Al can speak in other tongues octal commonly used in larger word oriented computer sys tems base 4 especially handy for graphics development tsec Moving Pictures p 9 binary for working with individual bits and ASCII for ease in text handling And he has various other capabilities you d ex pect such as being able to read and write tapes and to dump text symbol tables and the contents of memory to a printer Let s take a closer look at the three sides of AL s personality To program in assembly language vou must have a wav to get the mnemonic instructions into a form that can be processed In other words aneditor AL has that talent built in As does Editex AL has commands for entering text listing it deleting and changing lines or groups o
122. e directly as S You Be The Judge We ve decided to do something dif ferent with this contest Instead of judging it ourselves we re throwing it open to you You ve heard of a jury of peers Well you ve deen appointed Try the programs submitted by Interact owners and tell us which one you think is the prize winning entry Fill in the Ballot Box on the survey form to cast your vote You can vote only once no stuffing the ballot box allowed Vote for one program only giving the programmer s name and the title of pre ram as it appears here Please vote before December 983 We ll tabulate the votes and announce the winner in the next issue In presenting these programs we ve deliberately made no judgements about them That s up to you However in some cases we felt a little commentaly was necessary to help you use a program or know that it is running correctly Note that some piograms are stow in developing to the final effect we recommend you let them all run to conclusion before making your decision COLOR SPIN Programmer Bart Henderson Georgetown CT Adjust the value added to in line 20 b get different effects with this pregram e g AsA 08 10 CLS C 7 206 A A 8 30 X 1A F CONA Y LA A SINA 4 X X 56Y Y 38 50 F INI M 60 NEN A O0C C tfxf 60 if X gt 112 ORX lt OOR gt 7 ORY lt 0 TEMG 70 C4 THENC 3 20 FC OTHEN 80 90 FLO X Y C PLOTX 1 Y C AO X 1 C0 FA 0 K 1 4 1C 100 GOTO
123. e of sitting at an Interact keyboard and dimensioning at 30x00 data array And I stif had 3 7K left Thae s only 1K less than che original 6K machine stattcd with This added 16K means we re now in che big leagues Virtually every pregram published in magazines is fer a 16K stan dard At last a world of seftware is open ing up to Inicract owners A few facts Fhe expansion a fifth genet ation is of modular const uccion lt tequires the ad dition of a memery board and a power supply board The power supply is toral ly self supporting supplying all the power needed fer the expansion ahd future add ens The addition of rhe powes supply means your luterace will now have twe power cords but power is com mon to the existing switch The expats sion is designed to work with Micto Video s R 232 port and che upcoming if enough of you want it BASIC in R M The new board supplies its own requests geant and riming Address lines are Ally buffered Ie uses 4116 dynamic RAMs CONEANEH en Pape 2 REMARKS HE folks Well here l am a few hundred surveys later Tochose of you chat answered our questionnaire a big THANK YOU If you haven t sent yours in yet be sure to de it soon so well know you wanr co continue receiving rhe newslecter th Letter From The Editor ee es es a ee eer ss eye ft A 32K Machine Ae feest More memory a ae ae Legel 3 m 32K Boards expansion and power
124. e reports you can also cut holes for joysticks and other accessories His has pockets which serve well for transporting tapes and program instruc tions It cost Steve about 25 00 to make his carrying case and he feels it s a small price for a lot of protec tion Graphic Line Up Drake Diedrich of Gig Harbor Washington sent ina subroutine that computes angles and draws lines be tween any two screen coordinates You can add it to your BASIC srograms for producing additional graphic ef fects When you call it from your program pass the two x y coordinate pairs as X Y X1 Y1 and the color as C 1000 AX ABS X X1 1010 1020 1030 1040 JF AX 0 THEN AX 0001 AY ABS Y Y1 IF AY 0 THEN AY 0001 IF AY gt AX THEN 1160 1050 S 1 1060 IF X gt X1 THEN S 1 1070 A AY AX 1080 KF Y gt Y1 THEN A A 1080 D Y 1100 FOR B X TO X1 STEPS 1110 1120 1130 1140 1150 1160 1470 1180 1190 1200 1210 1220 1230 1240 1250 1260 F B lt 0OR B gt 111 OR D lt 0 OR D2 76THEN 1140 PLOT B 5 0 5 C D D A NEXTB RETURN Saf IF Y gt Y1 THEN S 1 A AX AY IF X gt X1 THEN A A D X FOR B Y TOY1 STEPS iF B lt 0 OA B gt 76 OR D lt 0 OR D gt 111 THEN 1250 PLOT O 5 6 5 C D D A NEXTB RETURN Typing Guidelines Richard Bandelier of Fort Wayne Indiana fashioned a device which he finds handy for typing in programs or data and also in graphics development He took a piece of scrap board 5 x12 x
125. ecimal or O to FF in hex It s technically possible co have addteases berween XK and FFFF bur iz s only possible to work with addresses that have hardware to check or put infozma tion into In the 16K Interact memory stops at 7FFF A final note All the routines fot PEEK and POKE given here ate for Level N and 3K BASIC If you are using Level I however you ll find thar it has some limitations POKES are not initialized when BASIC is loaded so you ll have to Load N Go almost One question often asked is how to get BASIC ro load a program and execute it without having ro ype RUN Sad to say i haven t found a way as BASIC isek would have to be modified to do this Micro Video s magician Tom Matulevich however came up with a On The Inside coniauce from Dabe home computet water We completed the software Interact had left unfinished and sent our a catalog The response to that mailing was the dectding factor it was overwhelming Interaet owners having been ignoted for so long were happy to find that they eould get new software repaits as needed and their questions answered We became eommitted to In teract Support Because both Dave and 1 had watched Interact go under and had evaluated the reasons behind that failure weve been able to avoid making the same mistakes We ve corrected as many of the deficien amp short seres of POKEs that comes close With this series of POKE seate
126. ed New products were aanounced when they were in little more than the idea sage months before chey realistically could be delivered A user mew slecter was talked abour buet nevet produced Customer letters inquities and phone calls went unanswered promises were made that were noc kept and Ineeract came to be viewed as eomplecely unzesponsive to che users needs To be fair muse say that this atricade was not utencionally callous It can pro bably be related to the structure of the company which was hardware heavy and marketing light There was usually only one marketing type invelved ac any ont Girne and there was far more marketin work to be done than one person coul possibly handle There just weren e people available to wriee leteers answer phone eslls teach taining cours write better documenration etc Financial constralines were such thae the company eouldn t sup pow the additional people requited to market the computer effectively A eombined marketing development problem parttcularly toward che end of lateract s history was thar they were simply eying to do too many things at one time In a last ditch effort Interact cried selling computers through Mont gomery Ward in the Houston a ea To date no eomputer eompany hz really been successfil selling machines in a den artment store due I chink co the technical nature of the ptoduct Interact was no exception Alrhough they had moderate
127. ed toward machine sales Instead the fecus has been en supporting the existing computer owners Micro Videe s ef forts along those lines have given Interact owners over a hundred tape titles hardware expansions such as the RS2 2 port 32K memory board Exatron Micro Sponge and the soon to be released professional keyboard better programming de vices and of course RAM Pages As dwindling machine supplies forced other firms in the interact chain to move in other directiens Micre Video was there to smooth the wran sitien We re still very much in the Interact business a D Fer Advanced Pregrammers Only Sounds Good Producing sounds in your BASIC Programs is fairly simple and straightforward Generating sounds in your machine language software is an entirely different mat ter To make life easier for you here s a routine you can addto your programs to make sound generation less ofa chore The routine is called SOUNDL SOUNDL requires the same two parameters that the BASIC SOUND command uses to produce sounds ex cept of course that the parameters are expressed as hexidccimal rather than decimal values Before calling the SOUNDL routine in a program you must specify these two values which are placed in the C D and E re gisters The first sound parameter must be placed in the C register which is the mixer control It blends voices determines attack and decay turns the white noise generator on or off and perform
128. el J One is at least simitar to others amp lready on the market The other to my knowl edge doesn t even have any remote cousins How does one go about mar keting something like this when ev esything I know about programming ts self taught in ten months It s likely to be a while yet before 1 can handle as sembly language If you can point me in the right direction I d sure ap prcciate it Y all take care and keep up the g0od work Yours Gordon Cameron Elizabeth City NC Dear Gordor Thouks Jor your individual support Youre right we do ueed it As Sor marketing programs you ve written we eacourage usert lo submit pro grams to us for evaluation and pessi ble inclusion in our catalog Send programs ATTN John Stout Yowl probably enioy our Gamesmanshi p article in this issue i outlines what we think makes a goad program M L a gram description indicates that pa k meg is used youre better off to try writing your own program from scratch based on the description Most of the BASIC commands are very similar to ours Radio Shack published a card listing all their com mands which because the Model is no longer in production you can usu ally find at a good price I just bought a reference card at the close out price of 30 For those of your who want to go further I d recommend a very good article on graphics for the TRS 80 Apple and Pet computers that ap
129. ement the first subscript represents the buildings which are numbered O and 2 The second subscript represents the floors of the building which are numbcred O through 4 where O is the bottom fleer This is analogous to the Euro pean style of numbering floors where the first floor is really one floor up and the lowest floor ts at ground level The third and fourth sub scripts represent the X Y coordi nates of offices on the floor where X 0 is the office farthest west in the building and Y 0 is the office far thest north The program references the dimen sions in the array to give you your lo cation at any given time If you were on the thi d f oor of the second build ing in the fourth office along the south wall see graphic above your location in the array would be A 1 2 3 4 In the game you always start out in the first building on the bottom floor in the office in the northwest corner A 0 8 0 0 The program dis x oman eet i T ETT EH i p ee plays your location then asks you which way you want to move up U down D north N south S east E west W or nto the next building Whenever you enter a new building you always start on the bottom floor in the northwest corner Based on yvur response the pro gram executes onc of several sub routines that control your movement lines 300 590 Note that each sub routine includes data checking to
130. enim Dear Micro Vidvo Thanks fur the great work you do in supporting the Interact l aim te order a new keyboard as soon as I get my Income tax refund check Hot damn Cal Ledford Franklin OH Dear Micro The new kevbuard is tepst Jerome Butler Babylon NY Dear Miciv Video l received my AL replacement tape recently and afler my hassle with As semblex I ve given AL a thoreugh work eut and was very pleasantly surprised with its performance It s a winner But 16 the tape received ss defective Will you please correct this situaten Howard Baker Urbana H Dear Hower With pleasure Wel always replace a defective iape Just return it with a nete and we ll ship another right out You should have gotten yours by now Glad you like Aff Fh elo e secrecy COMI FE Fy THE FHER OUH I FECA c 4 3 gt EEA Cbbtlhia t wile EPLE Bi G Le Dear Micro Video Your computer is great l bought it be cause I didnt want to give up the ability to program and now that have the pro fessional keybourd L don t have to But I m only 4 and I can only program in BASIC Could you make an 3K BASIC with u Compiler So when l m done with a program I could compile it with one command and change it to Machine Canguage Timethy Sallume Santa Maria C4 Dear Tim Unfortunately there s no reem lef in 8K BASIC in which to add a compile fca ture without teducings the prastamma le RAM even
131. ent Tape and Toel Diagnostic Ta warranty fet parts and labor Breaktlvough Beat the Clock Rovers e Cevwuter Maze Star Treck Arire Logic Combat Artillery Command a Farth Ourpost Superdsow Showdown 7 Complimentary one year sabscrip tion t RAM Pages You get experience points in the microcomputer maze with one of these treasures And we ll make your silver go a little farther by giv ing you 20 olf any software and ac cessories you order along with the computer Don t forget that part of the treasure is your first year of RAM Pages free Coupons in every issue are worth their weight in gold Sorry this discount cannet be applied to the basic computer purchase Quantities are lim ited Machines will be sold on a firat come first served basla Limit one computer per ocder c 16 ee z T ee a r e ee ol ae i aro i cane pie i pea ee as i Pie Grr Pe Men os ta ee ee T Se beads TS r tc Dear Sine Denim This ietter has nothing in partucular to do with the Interact iw even computers m poenerol AIT want to Kaew is how came you dow t have a picture over yotur celuain ike Bear Abby er Erma Bom beck Sines Tm a anan never particu larly vared what Marv Longe looked like From vour last colmnn vog seunded like a spunky young thing Is thore some iwa son vou dont want us to see whal vou look lke Maybe vou corld have a eor test where the closest acttt
132. enthustaslic about Mazes and Monsters from six year old kids to senior citizens n the action game side of the pie ture vou can blast radio active mat ter to smithereens guide a butterfly on a perilous flight rack up thousands of points on an electronic pind lt all machine or challenge robets in a life or death battle of wits The most explosive game in our summer catalog Hot Recks com bines space battle with a lunar lander Ta successive rounds of play you must destroy all chunks of radioactive matter that float around Se a 2 eee your wapa fend off attacks by an enemy saucer then land on the lunar surface to refuel The graphics in this game are superb from the opening planetary explosion to the lunar surface visuals Skill levels in the game let you vary the difficulty of play you ho how fast the hot rocks move through space and how often you can fire your half life laser Our critics agree that the hardest part of the game is figuring out how to control the spacecraft during the lunar tanding sequence Tired of shoot em up variants Wing It one of our newest releases provides a delightful change of pace The object of this game is to guide butterflies across a busy freeway and raging river to greener pastures Don t be fooled by the gentle sounding name this one s full of fast paced action and spectacular graphics that have the whole sereen moving in opposite directions Both
133. ents aren t used You can use Assemblex on multiple source Files to generate as much object code as your machine can handle combin ing the files after assembly with the Micro Video Monitor Editex gives you a number of pow erfu editing features It allows both line and character editing with com mands like APPEND ERASE CHANGE INSERT and SEARCH Its counterpart Assemblex is a full fledged multi pass assembler that first generates a symbol table then the object code It supports among others the SET equate pseudo op and allows you to locate your code anywhere in memory via RG As semblex wntes your assembled code to tape and Jets you produce a fill list ing of the source and resultant object code Assemblex Editex comes with ful documentation but it ts a program ming tool nol a tutorial on assembly language programming The instruc tions assume familiarity with 8080 asssembly mnemonics If you re new to this type of programming make sure you have a good book on assem bly language and READ IT Also in high demand has been more educational software Along those lines Micro Video now offers CAPIT Computer Assisted Personalized In struction Technique riginally de signed for and sull in use by the University of Michigan for continuing education courses CAPIT ts essen ually an authoring program that gives contei ct Puge Y The Computer Doctor SYMPTOMS Certain keys don t function prope
134. epairs and when I got it back it didn t work Who do you have working in your ser vice department anyway Chim panzees A It is frustrating to wait for your e computer to be returned then find it doesn t work But no we don t employ simian topen as technicians Every computer th shop is thoroughly tested both before and after repairs Then it must pass a burn in of at least 8 hours before we send it back to you However this doesn t always mean it stil works when it gets to you we ve discovered We ve got very lit tle control over what happens to your computer once it leaves Micro Video l4 at comes into our and unfortunately shippers some times treat our delicate packages roughly If your computer box is dropped repeatedly or otherwise mis handled damage can result Solder connections can break loose the RS232 port or a chip may pop out of its socket or the tape head can be come misaligned Occasionally a unit may leave owr shop in working order but fails al most immediately when its owner hooks it up and tries to use it This doesn t mean repairs weren t per formed Some parts of your computer are Just particularly susceptible to failure The A D converters joystick ports and other parts that interface with the outside world are easily af fected by static discharge accumu lated in a joystick or friem your hand for example You can reduce static problems by ground
135. eract news Itom up here in northern Wisconsin I ve seen a few people up here picking strawberries and their shirts said Ann Arbor Ml You ll like our style Well do and keep up the good work Mark Hadland Bayfield Wisconsin 4 MIGROTEXT Extensions You Gan Make When we writea program such as Microtext we try to make it as generally useful as possible We try to antici pate all the ways that people might want to use the pro gram We also try to leave enough free RAM so that the program can process su ticient data at one time to make it worthwhile In a limited RAM environment a program can actu ally have too many fancy functions What good do all those nifty features do if the program can only process a few lines of data at a time With the 32K expansion the RAM pressure is re duced The extra memory gives Microtext the ability to handle 7 8 pages of text at a time rather than just 1 2 And there s room to play around with adding some extra features B y adding only a few lines of cede and changing a few existing lines you can expand Microtext s processing capabilities to include automatic pagination insertion of keyboard messages into the bady of the text and more instead of making these modifications ourselves and releasing a 32K version of Microtext we d prefer to tell you how to change the program yourself Not only is this cheaper for you but it lets you pick and choose implementing on
136. ery en te tape He reports that vou can easily manipu late the saved picture from a BASIC program such as the one listed below 10 A 22272 B 163B4 C 2079 20 CLS 30 COLOR 0 3 5 7 40 FORI 070C 50 POKE B 1 PEEK A 1 60 NEXT Kidproof Joysticks E Elunsen ef Waukesha WI designed what he calls 2 more kidproof joystick The parts he used were gt The top shell cerd and three screws from the original Interact Joysticks e Five subminiature N_O SPST switches four wrth lappers A swivel mechanism e Iwo pieces of lucite 4 inch thick 5K pot and knob Cempression spring gt Cerd clamp Shell from felt highlighting pen Screws and nuts to mount switch E positioned four directional switches on a piece of lu cite isee diagram On the other picce of tucite he mounted the fire button and attached the tivo pieces with switchmounting screws and nuts He modificd the shell so that the pot and swivel would come through the top und the fire switch out the side He housed the swivel in the pen shell and assembied the compressien spring into the swivel ball After soldering all connections he mountert the lucite to the top shell using the original screws Assembly 4 switclics positiuned to deliver alf8 directions mounted on a piece of lucite Lucite pieces held together by HEL yi eae a switch mounting screw Switch for FIRE Button iis hie mounted on lucite A No
137. espense yeu want from your complaints if you fol low these simple rules 1 Be specific and concise about the nature of your complaint Avoid rambling generalized verbaliza tions of angry feelings and focus on ihe real issuels concerning you 2 Be specific about how your com plaint can be resolved Describe the action that could be taken to satisfy you Don t make the com pany guess or try to read your mind and you re more likely to get the solution you desire 3 Be reasonable in your demands Most companies are more than willing to work things out we d all rather have happy customers than irate ones But remember that the resolution of problems must be equitable to parties As a case in point theze s one Interact owner who seems to have nothing better to do with his time than to write lengthy hostile ra bling letters condemning us for ev erything we do have done or might be planning to do We try to sort through his vituperative verbiage but he s never made it clear what he expects or wants us to do to resolve his ill feelings aside perhaps from supplying him with ewe in our catalog free of charge His criticisms are neither constructive nor specific T SUP EE WE REFUND T WOOL fe HEY SEND Vie ANCHTHER OAE ET CHARGE CLOSE JME STORE ANT BAYE TE HAA ALERH 7 Sait w Le THAT HE iT Ae TORY his demands are unreasonable and the result ts that he s been labelled an impossible to
138. evace cumers are whas this newslerter is all about A shore timeago J was talking with some users The talk always seemed to take a negative tum The Interact can t do ehis The Inwrace can t de thas The What lt a me sallit azmpuses is better Hoguush You oum a fine computer No you can t run a general ledger package A floppy dise drive will probably never be available We ve go big letters and small memory bur I stil contend yex oun a fine computer Try solor graphics on a Heathkir Do you know how hard itis to get sound on a TRS 8o Atari is bragging abas de capa bility of playing an andio cassete through che T V speaker we ve had that capability ali along The keyboard on the T 90 4 makes che Interact s raised keycapslook like a professional keyboard Best of all try co ga an Apple for the cost of your Interact Your Interact has color graphics cones sounds reliable pe loads Microsofe BASIC a large software library machine language access and picaures eam to pro gram in both BASIC and mechine ian guage occess other systems and data banks edueate yourself and your family and even dosome ager tasks That s not so bad is ie chink the Interact has dynomite poten rial ste _ accepting it as it i and exploring and enjoying that ponio Tite leterand Nawork Newsletter is m a unique position It is endy an inccraafongl forum of all Interact owners We want you co we this publication co asi shareco
139. even come face to face with Death Mazes and Monsters is a gnme you can play for the rest of your life Each game has a new dun geon lavout and your character traits can vary widely There ar Copyright S82 Ahero Video Corpormion All Riehia Reserved Exatron centroller software cable wiring diagram and complete operating instructions with a sample BASIC 429 95 program to illusirate use Comp are against Exatron s list price 0f 399 95 which does zot include controller software FIGHT PUN SPELL USE ITEM over 65 000 possible game combinations WARNING The Video General has determined that Mazes and Monsters may be addictive 24 95 A butterfly s flight while free ts fraught with peril In this single player action arcade game your re a butterlly trying to get to greener pastures First you must cross a busy freeway avoiding being smashed by the fast moving semi trucks and cars Then flit across the river that runs alongside the freeway landing on turtles lily pads rafts and snakes that drift by The longer you play the more challenging the game becomes 19 95 Es v l a ia n ilg g E 15 T NJLIN sO SAYS SORRY LOOK Safe Cracker A terrorist group has infected the world with a deadly plague virus Modern sci ence has an antidote but the terrorists have sealed it in a booby trapped safe You ve rounded up a motley crew of sus pects three of whom can tell you
140. ex Editex seem to work but you ve been unable to write any programs successfully If a pro gram you ve written isn t operating as you intended don t necessarily blame the assembler Check your source code to make sure that all your commands are spelled correctly Misspelled commands may be inter preted by the assembler as unad dressed labels If Assemblex won t write a tape properly check to see if ou are using a DS pseudo operator immediately before the END state ment which must be the final in struction in every source file You Should be able te solve this problem by reloading the source into Editex and adding a N P between the DS pseudo op and END If none of the above is obviously causing your diffculties give us a call Together we should be able to find a solution ay Software contineed from pare 9 focus 1s achieving a high score in clude a routine that takes in and displays the record holder s name and score At the end of the game the player should always have the opportunity to play again at the same skilJ level or with the same game options SAME GAM without having to respecify them These f ne points can make the dif ference between an excellent and a mediocre program You may design a banner or front screen for your program although this is not required We do request however that you include clear complete documentation when you send your program to us It will get a more
141. ext 400 worth of software I ve picked out and then of course there s the Fype amp Talk All I need is more cash Barbara Bridges Badger California Dear Micro Video Thanks for sending the issue of RAM Pages and your catalog I was ready to sell my Interact until you came along Now I see that the only thing we Interact owners needed was someone to provide the hard ware and software we required to make our computers do the things others were doing Thanks again and keep it up Ryan Smith Forest Greve Oregon Dear Micro Video I am a new owner of a used Inter act I want to compliment you on bringing personal computing to those who can t afferd Apples or whatnot I have two comments 1 Your keyboard is quite atrecious frankly Even the improved one I type much faster and find it irritat ing to have to wait for the keyboard I have been looking for a replace ment keyboard and I wonder if you are considering one at any time 2 Your stringy floppy is marvelous but the price ts somewhat high For an extra hundred dollars why not offer a floppy drive Also do you sell wafers separately One last note I know you have stated that we are stuck with the current text limi tations of the Interact ll x I characters Have you investigated a separate graphics board There are some available for Apple for in stance 4 chars line 80 chars line Oh well despite the above gripes
142. f lines But AL can also do several things Editex couldnt He s got a string handling leature that lets you casily replace strings tn a single line or across a specilled range even the wh te program AL will also let you relocate lines in vour source file In all his editing functions AL will ac cept a label as the starting parame ter rather thim a line number This i convenient because vou don t have to remember what line numbers are associated with the various sections of vour code finally AL lets you de cide where to locate your symbol table and text rca in memory giv ing vou the flexibility to use its capabilitics efficiently Then there s Lee oe ki 7 d d y l pN S A i r p r j A 3 p pa f a x a sg z 4 7 he is A ai al ot eee SS erat ee Pa TW ote Ald eee E Once vour source code is written of e urse you must have some way to convert it lo executable form or ob ject code That s where AL the As sembler takes over AL recognizes all standard 8080 mnemonics plus a number of commonly used pscudo ops like DS ORG and SET In two lor more brocessings passes that build the symbol table and create the object code Al assembles your text hile into a ready to run program Find a mis take in vour code an undefined label m vour symbol table No problem Just call AL The Editor make the change then hand the Job back to AL The Assembler It s instantaneous no more endles
143. favorable review if we have a clear understanding of the pro gram s objectives options and oper ation We evaluate software submitted as soon as possible after receiving it But if your program arrives during one of our frantic times such as dur ing catalog preparation it may take as long as several weeks before we can find adequate time to give it a fair review If we like your program and want to add it to our catalog we ll contact you my mail to make purchase ar rangements If we like the idea but feel the implementation could be improved dramatically we may offer to buy the idea from you and do the implementation ourselves An ex ample of a program that reached our catalog this way is Video Derby If the program does not meet our needs or general criteria we will return it to you Wedo not duplicate software Sent in for review so you need not worry about ptracy Micro Video pays no on going royalties for software We do how ever pay reasonabie fees for exclu sive rights to programs produced by outside sources the amount varies based on a program s quality its re lative completion that is how much work we ll have to put in to polish and get it into marketable form and its overall appeal Remember that a good machine language game will always be worth more that its BASIC counterpart Also remember that the relative worth of the pro gram is proportional to our market size You might get more for t
144. ffort well worth the time chough as PEEK and POKE cake youone step closer to making your computer obey your every wish but you have to know the proper address and whac kind of infomation it eontains to do anything meaningful Seme loca tions you might want to look ints are ven in the Guide co ROM Subroutines and unde POKE in BASICALLY SPEAKING As you gain proficiency you can disa semble BASIC and leatn more That s decimal for an ASCII H Now POKE 25952 3 We have jusr put new values into the addreases thar store the OK prompt so it now prines HI in stead While this isn t exactly eatth shaking ir does illustate how easy PEEK and POKE are to usc Take a look at the way they are used in other sections of this newsleteer then strike ouc oo yout Own Youle on your way numbers don t reptesent ASCII characters but BASIC can tell che dif fecenee and will y ptint them so you ll see junk characters Some will however have the same value as an ASCII character and youll recognize those as they print on the sceeen en vex get the the ceal ASCII storage areas in BASIC you ll know it becauge the ler ters will form words For example loca tions 25956 through 25960 convwin the ASCII characters for the word BREAK which print when you stop program ex ecurion with a Control C This choi que can be carried much further of course See if you can diseover how to use it to unlock BASIC s secress a 9
145. field Bravo the editor s letter and thank you for your SUPport bought this computer from a friend almost a year ago and am thrilled to pieces withit It s notat all unusual to spend 30 hours a week glued to the keyboard Three to six hours at a stretch has become the norm This ts particularly satisfying as my roommate who spent big bucks the character is supposed to look and design my own You do have to mod ify the logtc in the program if you do this but then you ll probably have to do that anyway I d also suggest you take a ook through your computer s non standard characters and see if there isn t something simular Some of the published progtams use packing Line packing is essentially the process of POKEing machine lan guage routines into the hnes of BASIC code and our computer doesn t have the facility to do this Programs using packing will sometimes use character sets not aviailable on our machine and the line length differences can also make translation diilicult If the pro on an Apple Il with disk drive gets cross eyed after 45 minutes of trying o read those tiny characters When somebody in the next room uses an electric razor or something his dis play goes to hell in a handbasket while mine displays nary a quiver Un doubtedly for my purposes this is the finest product on the market One more item before I succumb to writer s cramp am working on two action games in BASIC Lev
146. gan to fix the paint job on his car After spending more than 50 000 I lost track of the money a long time ago Don reports he now has the world s only Interact contrelled Corvette My friends challenged me te make it inte a show car Don recalls For me it s really a fan tasy turned reality Electronic Protection Even an accomplished car thief wouldn t stand a chance at stealing this one The car is virtually un driveable by anyone other than Don or his Einstein assistant deff Mayes who devised most of the com uter hardware modifications For mstance Don wouldn t stoop te any thing as mundane as a key to start the engine You have te enter the cor rect fourrnumber combination from a keyboard on the dashboard a combi nation Don changes from time to time If you don t enter the right sequence in an allotted number of seconds you ll see PLEASE TRY AGAIN on the dash mounted five inch color monitor A second errant try shuts down the system com pletely In order to type the four number combination though you first have to figure out how to get inside the car since there are no door handles There are three ways to trip the door latching solenoids which are all ENE p ip Jaa E E a oe s nL ote aoe pac T bf ar E z i controlled by the Interact You can open the door with a ring but only if you know where the hidden metal de tector 1s There i
147. grograms coming t support the RS232 pore further some new games both in machine language and BASIC and perhapsanother language Then of course there s the memory ex pansion about which we ll be announcing details soon The expansion to 32K RAM will open up new doors for all us Interact programuuers Our future plans will revolve around thedesires of users They can be assured char our iptenc is tocontinue expanding the sofoware library acceso ries and support services as long as people s inter est for the Interact con tinues to expand It s a dandy little machine that still amazes me with it s capabilities after two years of working with it O 5 2 PUZZLING Fill in the words from the clues given then use the letters in the boxes to find the answer to complete the sentence THE om BASIC Answers in the next issue Product Notes eoninued from page t for the Interact That includes the secret commands PEEK POKE USR not in the original manual Each Ommand is given no less than a page some 2 or 3 and every one has an explanation and short program illustrat ing the statement MICRO VIDEO P O Box 7357 204 E Washington Sr Ann Arbor MI 48107 b s SOUAM RW HN 92 Command to read a tape Memory you can t write to The part that computes 8 bits Ser tal Make it go A Program jump daca MUTE BU For novice programmers this book is a necessity
148. h time for games as we keep him busy with custom programming for com mercial advertising displays Outside work Tom makes a hobby of electronics repair He enjoys music played on his high powered stereo system and his car a V 8 Sunbird that he describes as a semi raceecar He also dabbles in photography a Still looking for a Better Mousetrap We ve been very surprised at the limited response to the Better Mousetrap Contest To date we ve received only a few entries Maybe you ve been tee busy with your summertime fun to send yours in There s still time though The contest expires 1 31 83 and we ll an nounce the winner in our Spring 1983 issue The rules are simple What we re looking for are clever innovative ideas involving the Interact Do you have a really different computer application A new ap proach to an old programming problem The ideas can be hardware or software based but they must be your own The prize is 100 in products of your choice from Micro Video Here are the entries so far Low Cost Protection Steve Ward of Carlisle Ohio built his own custom carrying case to protect his computer when he carvies it to his friends homes He purchased an inexpensive soft sided suitcase several inches larger tnan his machine He lined it with foam rubber cutting the pieces to lit snugly and leaving a rectangular hole in the center so the computer will fit tightly if the suitcase is large enough Stev
149. hap pen to contain the ASCII values letter and number symbols for and K It s the OK rhat BASIC uses as a readiness prompt As you can see PEEKing is easy POKE to push in POKE is the complement of PEEK s le you specify the value to be siored in any paticular location This can be ex tremely useful and it an also be very dangerous You can POKE BASIC right Out of existence if you type the wrong ching or distupt a working piece of code so use Caution with POKEs Lee s use POKE in combination with che PEEK example above and see what we can do Type in POKE 25951 2 POKING AROUND IN BASIC THE ASCII HUNT One thing you an do with PEEK is ro rake a look ar BASIC This is sorr of like 24576 is 6000 Hex the starr of the main code of BASIC and our loop runs from this point until it reaches the endof the BASIC code 32767 What we are doing with this programis PEEKing each addiess consecutively and setting a vatiable vo its value V In line 30 we have the program print N rhe address in turning a microseope on yourself Try decimal then take V and try to print it this program as an ASCI character Some of the 1 REM DON T FORGET LEVEL II INITIALIZATION POKBG 10 FOR N 24976 TO 22767 20 V PEEK N 0 PRINT N CHRXV 40 NEXT Actually both capabilities are simple and sttaightfecward although using them co advantage wiil require careful snady to gain expertise You ll find the e
150. he same program for an Apple or Atari because sales quantities are poten tially much higher in those mar ketplaces But something s better than nothing and besides you get the satisfaction of havrng produced a marketable product in conelusion whatever your interests game education busi ness personal data management software for profit or just for fun get out there and program your compu ter With a video game you react to the machine dance to its tune When you program your computer you make it od to you After all isn t that why you bought it ay MICRO TEXT continued from page 18 between each page instead of 6 Simple You d change the line counter limit in line 1500 from 61 to 31 To increase the number of blank lines inserted between pages you d change the maximum value of the variable Tin line 1505 from 6 to 10 And More Finally you can even modify Microtext for use without a printer by changing all LPRINT statements in the program te PRINT statements with RS232 BASIC The utility of this modification is highly questionable however With our current 17 character line limitation you ll undoubtedly consider the re sultant screen display to be unsatis factory Maybe you ve made some changes of your own to address needs we didn t envision If you ve got code you d like to share with other Mic rotext processors send them in We d love to do a follow up article based on
151. he Inceract s three BASICS litis involved enough thar co list the table of contents would more than fill a page It gives you a run downonthe parmal irti ers talks aboue funceions graphics strings game programming data sub routines special hims and the unique functions of RS2 32 BASIC All of these and more are explained in detail with lots of examples and commented list ings Know how to draw a checker board How aboue 3D lettering color rolls oe shimmering Do you really un erstand string and array handling how co debug your progsams and how to compact programs ep squeeze every available byte ineo them There s even an arcade type game program that s fully explained The second half of the book isa refet ence of aii BASIC program statements sorvin on Page 8 FOR ADVANCED PROGRAMMERS ONLY Adding Machine Language Subroutines To BASIC Programs You ll find the technique described below useful in two ways First it helps determine where to put your subroutine Secondly it allows you to save both BASIC and machine code in one program When you write the BASIC por tion of your program enter the POKEs for your USR jump as 00 Later when you ve determined the proper location and enrered the sub routine you can change to the proper address without expanding the BASIC program and oveirunning the machine language subroutine When your BASIC code is done PEEK locations 19709 and 19710 decimal
152. he nee Compu ter Doctor repair manual ft descrifes end tilusiraltes fises fur this anel many Other cammon prohiems SucNenim Dear Micro Video Cewn the Interact IGK did not pue chase the unit for use as a anphisticaled tov and therefore am not interested in entertainment programs am a pro fessional biologist weed biologist and botonish and hope aller Jeaeniag w use the Interact Teun use it in omy work would like to see Micro Video develop software for use inr Dielogical statistical work plant and insect distributranal etudies etc Such work is done l realize using much More sophisticated compaut ers but having only modest nancial re sources I hope do use the Intc ract J would like bo compliment Micro Video for providing suppolt fur those of us owning Interact eiuipment There ts no microcomputer business here previd ing products for use with the Interact Keep up the good work Sincerely Everett l Flall Phoenix AZ freer Everett Since there are only a few thousand Interacts around ant segntficwuly feawr bintogists tn the Jnieraci communtiy we aren likely to devote resources to this type of sofliware Have vou considered eriting vour wen Or perhaps there are other scientists out there who cae help You aut Anyone out there haw the bug for ihis hiniel of unr h Sue Dene a k E Ta kea a pra iah a a ee i S an s is m a ee eT E I po ee ge al Te k ai B
153. her than as an actual num ber There are many other ways to in eet tengeesh ame peet O a The amount of software that s coming out now is just overwhelming so rather than run lengthy discussions of each I though J d just give you some highlights of a few of the many new items available All of the new software I ve looked at is pretiy ex citing so I suggest you identify your own area of interest and explore pro grams that fit your bi First near and dear to my heart GAMES Micro Video released three real blockbusters in their last catalog Alien Invaders is the game most re quested in the surveys You asked for it you got it Hoards of invaders hever overhead constantly moving from side to side and dropping lower and Jower on the screen Can you shoot them al before they destroy your protective bunkers and you This game even has a bonus flying saucer Joystick contro is exception ally smooth in this game and you wont believe how fast the visuals arc If you re not aware of this game you must have spent the last few years ina cave or on a desert island That applies to the second game in the trio also Packrat You chase round the playing field collecting dots Program Notes and avoiding the iitele beasties that chase you Eat the megabytamin and chase them back for added points Special bonus points in this one too The third game has my son s sez of approval Space Base is an ex
154. icense for the computer We re n the process of petting more machines out into the marketplace you ll see them uwdveitiscd during the fourth quarter of this year lat f Memory Expansion 92K certintied fron pipe i peripheral interface The memory ex pansron is not required but it is fully compatible Micro Video also will be releasing a method of adapting the RS232 port so that the second pon on the board will have hand shaking capabilities This will allow you to use the Sponge and a printer simultane ously The price of the Sponge is not yet firm bit the package which in cludes the Stringy Sponge operating PROM connector cable and complete instructions is expected to sell for about the same price as the Sponge alone bought directly from Exatron Please do not order yet The price and other details will be announced in your next Micrs Video catalog at that lime stock will Se available for ship ment Meanwhile siart dreaming about ail the things you can do with your computer and this exciting new hardware option T REMARKS continued f rom page because of increased demands on my time this will be my fast tour as your editor I m sorry to go but know the newsletter will be in good hands hope you ve enjoyed my litte pearls of wisdom that have graced the past issues and hope your computer IS aS pvod to you as mine has been to me Keep reading keep learning and keep on comput
155. ich is bigger than the value given for validity He says that due to rounding in scientific notation the number 1002200 given as the value to be compared in the checksum is actu ally around address 32738 rather than 32767 lf you change the value of T to 1002361 the program should run properly and only indicate an error when there really is one Microtext Mishap Several users found a typo in one of our Microtext Extensions article last issue that caused a syntax error In the Page alter Page section line 1510 should read t510 LPRINTY AB TB KS RETURN Oops Sorry bout that a 7 Q Help My RAM Pages and catalogs are cither arrtving late or not at all What can I do A Unfortunately we are both pretty much at the merev of the US Postal Service when tt comes to third class bulk mail which s how those pieces are mailed Unlike first class mail there is no wavy to tracc it Also third class matil takes last priority and the mail delivery people pretty much deliver it when they can or want to get to it Ac cording to the Ann Arbor office de livery is Supposed to be within three days of arrival at your local PO However they tell us it could take up to three weeks to make its way from the Detroit Buik Mail Center where all bulk mail from SE Michi gan goes to your local PO Unfortu nately we have discovered that these times three days three weeks dont always coincide with reali
156. icture is eight pixels two bytes wide and seven lines tall That s a total of 14 bytes to be converted to hex for the table In constructing pictures and tables remember that your picture must be represented in full bytes that is it must be de signed in increments of four pixels egin at the upper left most byte of the picture and moving left to right determine the appropriate values to construct the picture table In this case the first byte is easy four red pixels in a row 95H The second byte is three red pixels followed by a black 15H The first line of the picture table which we ll assign the label FACE is FACE 55H 15H Continuing this byte conversion of our picture we end up with the fol lowing table FACE 35H 15H OF DH IFH OEOIMAEHR OF DHAFH oCH 0CH OF CH FH OF OH G3H Your picture table defined you can now access and move it te the screen with the BYTPIC routine listed below GIC MOV AC NOV B GYTP1 PUSH PSW PUSH B CALL BYTOUT POP B B A ZOH Nev CA B et Up Counters B POP PSW DC A JN BYP BYTOUT MOV Get Next Picture Byl A sNiove It The eau O NZ BCYTOUT RET Sox Fo call BYTPIC you must first specify four set up parameters register B horizontal size of pic ture in byles C vertical size ef picture in lines DE sereen address where upper leftmost byte lo appear HL address of picture table Youd p
157. idings You have to rely on your considerable athletic skills to scramble through a ladder and scaffolding labyrinth in an allot ted amount of time The faster vou climb the mure points you score But that s not all There are hazards to thwart vour passage On the first side of each building you have to jump over fast rolling barrels or use finesse in Your cfimb ing to avoid them altogether Onc slip and they will knock you off the scaffolding You also need the agility R 35 00750 a of an lympic long jumper to leap over gaps in the platforms You encounter new mere intri cate demands when you climb the second face of each structure This time barrels are being pushed from the rovfieps and there are few hid ing places The patern is alse more cemplex There are more ladders and narrewer platfermns which make vour jumping far more treacherous Jumping too soon or too Far which are easy t do will send you plummeting iu the pavement Yeu start off with three tries to climb the buildings and you can earn a maximum of five additional lives as you progress This game will keep you jumping and make you wonder ow such an uncomplicated game could be so darned challenging SILVER DRAGON GOOB NESS GRACIOUS GREAT BALLS OF FIRE In the imaginative Silver Dragon a fantasy action game you the flying dragen must OOLEOC 444 Ta 5 jar le eae pretect the 10 beautiful syimhs who inhabit
158. ile ther owners go out and frolic in the sun As the days get shorter and the leaves start changing colors people once again start to think about adventuring into mazes to fight monsters zapping invading aliens writing those great programs they conceived in the spring etc Our production of RAM Pages has suffered from the summer doldrums too but we re back in the swing of things now Thank you alt for sub scribing and also for your patience in waiting for this issue to arrive I romise you won t have to wait so ong fer the next issue As we expected we have met some resistance to our conversion to a sub scription format Some people ques tioned the subscription price and wondered if the maga ine was really worth 5 per issue Perhaps some of you have had similar concerns but I m confident that with discount coupons and other subscription spe cials alone not to mention the con tent you ll feel you got a bargain Get Involved With coupons contests and so forth we ve tried to make RAM Pages more than just a newsletter Our objective is for it to be YOUR forum for the exchange of informa tion and ideas We want it to contain the kinds of articles you want to read with the kind of information you find relevant We have lots of ideas for ar ticles but it doesn t do either of us any good if they aren t what interest you It s critica that you let us know what you want Obviously you cared enough about RA
159. imits on che answets INPUT INSTRS Wrong wrong Both INPUT and INSTR suspend program operation for user input so there s no way to keep a timet running accurately So how do pa write a Quiz program with a time imit You ger 10 poines if you said PEEK When you re running a user input pro gcam with time Censtraints you must maintain conttol co be able co keep evack of the time In BASICALLY SPEAKING page 10 57 we are given an addtess thar when PEEKed will return the ASCU value of the last key depressed in decimal You can PEEK that location to watch for keyboard activity while keep ing your clock running In this sample prog am wel use a sim yle srep timer You can control the cime limi by changing che value of YF the time counter We firse POKE the last key depressed address 24529 co 0 co clear it Nis the value PEEKed In rhis piOgiam we are looking for a I 49 in ASCII decimal In your own Prga you would check N agas nst another variable char has been set to th correct answer Where we hav pur th END sratements in this program you would put the br nches GOTOs to the next pait of your program 10 POKE 24629 0 EK 24529 40 IF N 49 THEN GOTO 90 50 IF i one GOTO 110 I 70 IF T gt 100 THEN GOTO 130 80 GOTO 30 90 PRINT CORRECT 100 END 110 PRINT WRONG 120 END 130 PRINT TIME S UP Another merhod of keeping time is t PEEK the clock An example of this is given in th
160. in As for me well Pil stitl be a computer freak just like yOu oa for more new goodies from Micro Video Sincerely Marv Long Editor GASIESMANSHIP EXPLORED comiter f ntt Pate 3 corporate graphics into your sconng or status display try to use them You can sometimes use inferiudes as a logical point in the action to display the current score These can also contain clever graphic effects or ani mations that reward a player for having hung in there Pac Man s cattoons are an excellent example of this technique Interludes can also provide a much needed break and chance to relax for the player in a high tension action game Store tice current high score and its Player s name within the program and display it along with the current player s linal score This lets players evaluate their scores and adds the in centive of having a score to beat In clude code that accepts a new player name when a new high score is achieved Scate veur scoring so thal average play yields scores in the hundreds or thousands rather than ones and tens Points don t really cost you any thing so why not add an extra zero or two A player will get far more satis faction from a 3 7 score than froma paliry 37 Put strategy in action games Make missed points or bad maneuvers cost the player in lost points re duced game time or number of turns at play ft shouldn t be possible to set S record high s
161. in size and cut a lengthwise slot in it about 2 degrees off per pendicular He cut the slot about two inches from the front of the board slanting it toward the rear He made the slot wide enough that a clipboard slides in and out easily He also cut a piece of plexiglass about the size ofa clipboard and added a clip clamp to the top which he uses in graphics development He places a piece of graph paper over a drawing then uses backlighting to make tracing the picture for adaptation to the screen easier He found that stretching a rubber band over a plastic ruler on the clipboard gave him a moveable guide to use when typing in programs or data As an extra feature he even routed a gully on the board for his pencils He states that you can change the dimensions to meet your needs but remember to cut the slot forward enough that the device won t be top heavy Cursors Foiled Again Les Woolsey of Ottawa Ontario originally submit ted this as an entry to the Small Bytes contest Weruled it out as an entry because it was not a complete pro gram However it s a good and useful idea so we ve en tered it for him in this contest Les reports that he s used several methods of tracking a cursor across an area of the screen Aside from the problem of writing and erasing the cursor itself there are two major problems in following the joystick One is converting the value returned by JOY into delta X and delta Y values the other is
162. ing malady To check this you ll need to take the top off your comp ter again and turn it over so you can see the underside of the tape drive Locate the read write con tacts which are mounted on the metal frame directly below the cas sette buttons see drawing You ll see that there are two sets of contact WRITE g7 READ Tape Drive READ WRITE Contacts switches One or the other will al ways be closed If no cassette buttons are depressed or if the READ key is down the lower set of contacts should be closed Depress the WRITE cas sette button to watch the upper con tacts close For your computer to be able to read a tape the READ con tacts must be connecting If they arent gently bend the metal strips so that the contacts are touching Then before putting your computer back together make one other quick test to make sure the tape drive itsclf is functioning To do this take hold of the thin drive belt and rotate the drive shaft The belt and drive wheels should move freely 1f they don t the tape molor is fro en In this case the only solution is to replace the motor or the entire tape drive We have parts in slock call for current pricing if you want to perform this repair yourself nce again reassemble your unit and try loading the tape With each of the above procedures we ve been trying to avoid the ulti male selution surgery However if all other lests have failed the prob
163. ing programs When there is it s because we Feel there are stil ways to make the software betier or bugs to be removed This was the case with VideoCalc and BREAM which I know some of you have waited patiently for These are now finally available We appreciate your patience and hope youll find that like fine wine they re worth the wail Some hardware items are not always on hand The RS232 Peripheral Inter face is often on a back ordered status due to high demand we gust can t seem to keep ihem in stock We re cently began assembling more con trollers so they are back tn stock Controller extension kits will no longer be offered We fill all back or ders on a first in first out basis Q2 Why do some programs require Microsoft 8K Fast Graphics BASIC in stead of my Level I1 Why so many BASICs This is a guestion I m often asked Microsoft 8K BASIC ts an extension of and replacement for the older Level Il BASIC We developed it to correct a String handling error in Level II and lo add kuster graphics capabilities We also took oui the PEEK POKE limits All your evel Il programs should run under 8K BASIC control with no problem However the reverse isn t truc and most of the BASIC pro grams in our catalog do require 8K BASIC Trying to run them under Level Il control will result in syntax errors since the Level i interpreter simply does not understand or recog nize the extended PLOT format Q3 Do I need R
164. ing the program with GOTO instead of END so it would run continuously In those cases only the continuously repeating or more complex ver sion is printed here if you supplied a name with your pre pam we used that name If you didn t we gave it what we It was a descriptive title Ballot Box on page 26 TUNNEL VISION Programmer Jim Loots Ann Arbor MI 10 CLS COLORO 0 0 0 20 FOR Z 1104 30 READ QOILRRI 40 FORX 11010 F ORY 1707 SO C X FY gt XTHENCH Y 60 OUTPUTCHRS1 0 X 5 R Ob7 5 RIC 70 NEXI REXT 24EXI 80 OATA 11 45 35 1 L4940 1 1 90 40 3 3 50 35 90 FORC H04E0UDRC C 3 C42 C 3 100 FORN 110 100 NEKI NEXT GOT090 Change dine 100 to 100 FOR M 1105 POT O NEXT NEXT GOTO90 and you ll be able to use the left joystick pol knob to control the speed OPTICAL ILLUSIONS Programmer Peter Finch Tigard OR Use the p t knob on the left joystick to change the illusion 1 X Q 0 X 0 4 X 2 3 X 3 7 PL010 39 157 39 OEFFNCY 7 X0 5 2 ANO3 2 PLOTS7 39 256 38 PLOTS 0 1 56 39 PL0T0 0 2 57 39 608 0108 C 8 1 3 H 37 174 M0157 H 39 C H H 9 0157 39 C 1HJ1M OTS7 39 H C HB 4 PLOTS H39 W_C UUENEXT FORS 11037STEP2 W 1 1 2 C 14 S MOTS6 39 1 C 1 39 1 F1 010 39 C 3 57 1 it PLOTS7 H 39 1 C 2H39 1 6 PLOTS7 39 1 C 1 1 39 tPLOTS 39 1 C43 H 39 I PLOWS 1 39 0 2 56 H 7 PL O1S 7 0 C 1 1 1 39 1 P 0157 1 39 H C 3 56 1E PLOI57 0 C 2 4 39 3 PLOTS6 1 0 3
165. ing yourself touching something metal before you operate your unit This is espe cially important during seasons when the air is very dry Power surges can also cause prob lems for your computer They may in termittently affect tape loading or have more dramatic effects Any major appliance which draws a lot of current such as a refrigerator can cause surges threugh a pevwer line so you should avoid plugging your com puter into a line that shares power with one If you have no choice you might want to invest in an electrical isolator They re relatively inexpen Need help Call 313 996 0626 sive and eliminate power surge related failures Whatever the reason if you get your computer back from repar and it doesn t work naturally you re un happy with Micro Video Believe me when this happens we re just as un happy about t as you are But in any case we o stand behind our repairs Just send your computer right back to us a cranky note is optional and we ll put things to rights At no extra cost to you of course I ve got your Assemblex e Editex programs but they don t seem to work on my compu ter Could it be my port Do I have a defective tape Help You didn t describe how they o don t work The way a program fails can tell us a lot about what s causing the problema First of all ifyou have a port other than the Micro Video port the pro grams will not work on your m
166. is provides a firm stable mounting The Hina out med is now complete You may also wish to have audio out in which case you will need to 1un a second RF cable from the audio con nection on the left side of the RF sec tven see photo and schematic then out to your monitor If you really want to get creative you might consider duplicating the RF circuitry on the arid board along with the transistor circuitry to m plement a switchable system that lets you select either RF or video out This is extremely complicated how ever as it requires a number of sets of dual leads and aswitch with as many as 16 positions So far as we know this has never been dene amp Right Printer continued from poge 3 and does not print some characters adequately and a user who owns ene reports that it is quite noisy Its mam advantage is price The newer DMP 120 is priced at 3499 and for the extra 100 you geta notable increase in quality It is st produces dot matrix characters and can be set to parallel operation for compatibility with other computer systems At 699 Radio Shack offers an ink jet printer which produces dot matrix characters in up to five different col ors The colored ink comes in car tridges which you load into the printer Top of the line is not top dollar suprisingly 799 buys you a letter quality printer that uses a daisy wheel element similar to the circu lar attachments in man
167. is that the price is only 79 95 The bad news is that the keyboards aren t in stock yet We ll get our first delivery of 130 keyboards in early Nevember But more goed news we ve included a coupon in this issue of RAM Pages that gives you 19 90 off your keyboard purchase when you order by December 15 With the new Professional Icey board youve got the keys to success al your fingertips Whether you re programming in BASIC assembly or machine language playing aooanannoann poggoaocanrnoonrt Sores ee ms SS ToS patie Reybonr ai dri iven games like RS Ae venture series or typing your data into a business program like DREAM or VidcoCalc vou ll do it in style What more could an Interact owner ask for il know I know higher resolution Don t give up We ll crack that nut vet letter From the E elitor Remarks The times they are a changin wrote Bob Dylan back in the carly sixties and his words still ring true Micro Video certainly has undergone many changes over the past three Years As we head into our fourth vear in business I d like to take a few minutes to refec un where we ve been and how we got where wt are now When we started our support for the Interact uur intention was to provide u place where abandoned owners could get their computers re paired questions answered and back up copies of the then availadle software Oh maybe wed bring out anew program or two but n
168. ision as much if not more than the actual price If atl you want is an occasional rogram listing you ll probably be lappy with a basic no frills printer which can be had for under 400 sometimes as low as 300 If youneed to print four columns of mailing labels or accounting spread sheets you might want to consider spending a littie more ona printer with a wider carriage If your objective is to p duce correspondence or documents in conjunction with word processing sof ware you might decide on invest ing in a more expensive letter quality printer Printer Characteristics Most basic printers are fairly standard and close in capability Many have compressed and extended print hold face and some graphics capability Most printers use a dot matrix format for producing charac ters where each aractir is com posed of a group of dots much as characters displayed by the Interact on the screen are made up of pixels The dots are perceivable by not teo close visual examination Some prin ters use elements similar to those in electric typewriters to produce smooth one strike characters You might easily spend 2500 to 4000 on this type of printer probably not justifiable for typical home use although some are available at substantially lower prices The Interact s only real require ment of a printer is that it be RS232 compatible and you must of course have an RS282 interface installed i
169. isk so the cost weuld be considerably more than junt an extra hundred dollars Fin ally were working on the graphics limitutions problem Dori have any concrete details for You yet but stay tuned The Editur Dear Micro Video I would like to see a good program for sending Morse code RTTY and ASCII with programmabie messages that uses one joystick firebutton output to go to the transceiver audio circuit Also I d like RS232 output for a printer with selectable baud rote that automatically selects re ceive speed and prints it on the s reen 1 Should have a software de bouncing and print on the screen It should be able to re eiye while you type the text to be transmitted using one line that goes to the tape record head through a keying circuit and then to the input of a transmit 12 routines and access them using an ON struction Thanks Bob a ter Keep up the good work and thanks for the catalog Richard Thompson Santa Ana California Bear Richard Whew A tall order Cen anyone ouithere help this man i know we ve got some hams in the crowd The Editor Dear Micro Video When we first saw an ad in Popu la Mechanics I thought maybe the Interact was a fly by night company But when my brother and I sent for it we really enjoyed it For one or two years we were happy until a dreadful Tuesday June 8 1982 we awoke from sleep and to our horror found our Interact computer totally under dirty
170. ith the capabilities lf this doesn t pique the experimentor in your soul nothing willl a LI MICRO VIDEO P O Box 7357 204 E Washington Sr Ann Ardor MI 48107 FRE 16314 eoninsed from page The added memory sie from 3000H co _ BFFFH With the expansion we now have a rotal of 32K contiguous memory Afer subtracting the screen and variable space about 29K remains With BASIC loaded there is over ISK of program space plusanother 4K chat can be used for USR routines The new 32K BASIC is an enhanced version of Microsoft that combines the faster graphics of 8K BASIC and the port access commands from RS 232 BASIC The I O conc ol for RS232 ac cess has been improved fet fasier aceess co peripherals A new gtaphics com mand LINE has been added iz lets you draw a ine quickly benveen any two points on che screen The USR function has been modified for more direct access to machine language subroutines Also available is a program to relocate BASIC progtams wsitten with other vetsions to the 32K environment Unlike the Micro Video RS232 pert che exp nsion is not userinstallable A number of modifications to the Insexact incluch ng diilling holes for mounting are r quited before the expansion boards can be put in place To ensure rhe best possible quality control Micro Video decided do custom installations which includes extensive testing and burn in Once installed the memory board resides within your In
171. ived a shock force in excess of 20 GRAVITIES Did anything survive Yes the crew had no personal casualues The ship sailed on to Pascagola Mississippi NEW CONTEST A Better Mousetrap If vou didn t gel the gOOdies on your Small Bytes program or you didn get your entry in shame then here s another chance Send in Your favorite hint or tp Have a clever idea that Youve in corporated into your programming Feind anew way la protect your com puter when you take it somewhere Got your computer doing something special Share your knowledge and win a prize Ihe only require ment this time is that the idea must be something vou have already used with your own computer no wild untested dreams please software hardware underwear what have you Keep them brief sorry and don t worry about the waiting Well take care of thal During this tame my Interact was in Aad the interact Well had to realign its box strapped to a workbench a_ the tape Acad but then it was business mere three inches from a bulkhead as usual The prize 190 00 in Micro Video procduce credits Take the loot from Captain Video Send your idea in now that s wail for all you non naval types that faced the blasts I d pro lected it from falling objects with two layers of bubble wiap Program Notes coutlaied fram pige d you asttuctury to work with in creat ing your own educational packages CAPIT u
172. l 3 Tve buen unable te reproduce such problems suspect such occurrences may be the result of a bad tape save or confusion on the pla_ver s part rather than a defect in the program code I want to thank those of you who pointed out probtems and sent us vour saved game upes for testing and debugging If you encounter what you believe to be a bug jo Mazes and Monsters encourage you to re port it Tu assist us in identifving and resolving such prohlems quickly please save the current game status ut Lape and send the tape to us Sorry but we cannot restore b tehed game tapes or make special charac ters itike Dwarves with super i and 1000 hitsi We will however supply a new blank tape to replace the one veal send to be checked If vou have an ol cy version ef the game we will replace with with the newest version al no charge Simply return vour old copy to Nlicro Video for replacement anc we will keep vou posted on updates in the game If vou Gnd the Ob and get back te the Castle with it Jet us know Not many have survived the quest so far 2 if M Come in from the cold and subscribe to RAM Pages Tidbits Mazing and Moaning f you are tired of wading through the 12 pages of Mazes and Monstcis instructions we have just the thing for you Jonathan Wright of Middletown OH sent us a nifty one page condensation of the instruc tions Featured are summaries of ac tive keys character traits mon
173. l as a sleeper the game has re ceived rave reviews from some sur prising sources and we expect its popularity to continue growing in the months to come There are ol course many other excellent programs in our catalog Just because thev re not mentioned here doesn t mean they aren t fun we simply dont have room te cever them here Jf you d like additional description of any piece of software just give usa call We ll let you talk to our resident addict of that par ticular game Programs programs every whore i MA 32K Cerner VideoCalc and DREAM A Closer Look Before the expansion to 32K RAM it vas pretty hard to take the Interact seriously for business applications A program of any real complexity and utility would take up all the available memory leaving no room to store or manage data in any appreciable volume With the 32K expansion that situation has def nitely changed The Interact now has the potential to be used as a smail business machine The proof VideoCalc and DREAM Both VideoCale and DREAM re gawe a 32K RAM system Both are designed to produce printed reporls of data on an RS232 compatible printer although a printer is sof re quired to use either program Each program is fully documented in a 60 page manual that includes a re ference section an entertaining walk through of operation to get you started acini information and a complete program wie They wer
174. l the right pieces in all the right places All youdo is remove the old keyboard assembly PC board and all then slip in the new keyboard unit Attach the ribbon cable reassemble the case and vowre off on the road to success Yauve got the keys lo take you anywhere vou want to go You ll love the feel of the sculptured keys beneath your fingertips The keyboard action is smooth and responsive you won t have Key bounce te kick nvound any more No mere double character s as you type no more worn out contacts that give no response The manufac turer reports that keyboards in ac tual use have lasted over 100 000 000 key cycles without fail ure Your fingers wiil probably wear out before vour kevboard does A couple of differences between the new and old keyboards aside from the obvious of course while relatively minor are noteworthy Dont automatically reach to the upper ee section of the keyboard to type a1 for example We ve moved tt te i traditional location the leftmost key on the top row Looking for the divide sign or slash It s still in the same place but jts key legend now bears the more rec opnizable not 7 We ve also changed the twisted grey ribbon cable to a plug compatible flexible heavier duty ribbon cable that is less likely to break Now that youre all hot and bothered over this newest hardware enhancement for your computer I ve got good news and bad news The good news
175. lat ry mrm e aide anid 1 hppa or ee ils ave rt lt itee bbb bined bh bi Ph EELE Egaga BREE eeu Liana Lit ina ETT ap ie tl Sianna a tnhhe z i i i T k diii i bei ipag i i s ee TAITH PERR REET ceeds sanasa 1 ib teeeredt peoseefee Golda bo Peete PT LETT G ArT EE minm i k eet Sound Off Richard Fagley of Sarnia Ontario lashioned a re mote volume control fer his Interact He says the piercing sound of tape leads is what prompted the modification Richard replaced the audie eulput of the Interact with a 1 0M potentiometer about 2 at Radio Shack and uscd shielded cable to run it to the upper housing next to the reset button The Interacts audio output is located at the extreme upper left corner of the RF section at the top of the main circuit board Fhe petentiemeter replaces R109 If you don t want volume control he reports you can use an on off switch instead Socket To Me Jim Purcell of Milwaukee Wi gained 2K of extra RAM in his Interact by inserting a 6164 static RAM into the empty R M socket inside the Interact With this nwd ication he has a nice little chunk ef RAM sitting dewn at 800H that l can use to write auxihary machine language programs He toek the static RAM and carefully bent pin 2 outward so that it wouldn t go inte the socket when he plugered it in then he took a short piece of wire and tack soldered it to the foot that s stickin out and to the 80 W line on
176. lem is definitely in the audio cir cuitry on the main electronics beard This is one of the most difficult prob lems to trouble shoot as the work ings of that section of the hardware are complex If you want to try the surgery yourself use the schematics in your service manual and investi gale the following chips for malfunc tion 1C60 IC61 C28 IC30 IC33 recommend you try this only if you have an advanced electronic back ground Otherwise your best bet ts te send it te our service department for repairs Please remember to include a note describing the problem P S Twe other items worth mention ing Your television may emit a stron electric field from its horizonta sweep circuitry If your computer is directly in front of the TV screen this field may interfere with tape loading Interacts with 32K RAM seem to be par eae susceptible to this inter erence The easiest way te determ ine if this is the cause of your load fail ures is le turn the TY off while load ing the tape If this solves the problem you should consider changing your equipment confiig uration moving the computer farther away or to one sideof the TV screen Also some people have returned their Microsoft BASIC tapes or called to complain that they don t work If BASIC appears to load cor rectly but you p et an M ERR R every time you try to enter a com mand you do not have a defective tape zar is there anything wrong with your computer
177. like Gamesmanship Explered and articles like Hardware Hints wll tell yeu how te breaden your Interact horizons and get the most eut of your computer We wen t forget you ad vanced pregrammers either spe cial columns will continue lf youlike to see your name in print send us a letter Unless it s full ef expletives which we d have te delete ident we have Richard Nixon te thank for that expression we will in all likelihood run it in Feedback In additien new preducts will be previewed in Pre gram Notes before they appear in our catalog for example sec page 12 in this issue And of ceurse yeu ll learn as much about Micro Videe as yeu ever wanted to knew Maybe mere This decisien te charge yeu fer the newsletter is we believe a natural step in the evolution ef beth RAM Pages and Micre Video Were com mitted to supporting yeu because yeu ve slaved such a significant role in the grewth of eur cempany Our geal is continued giowth fer both ef us and we are cenvinced that this is the best way te achieve it Now get out your pen and fill out the subscription form on page 18 As an added bonus if veu write the werds Sue Denim I want vou anywhere on the order form you can erder any Micre Video tape fer kalf price along with your subscription This is just the first of many ways you ll save when you subscribe to RAM P ages Sincerely Sue Denim Editer EIS ran U p abe
178. low terrible 2 1 2 3 4 5 Fast pood A e ypu generally satisfies with the coftwate availabie fee the Interact LJ yes LJ xe Please sank your interesi in the toliewing types of softeare and psdducts Ne Veni Interested Interested Acton Games r 3 a 5 Strategy Adventure Games 2 3 4 5 Simutalson Prog rams l 2 3 5 Educa benal Progsams l 2 3 5 Peesana App tcatkins I 2 3 4 5 iome budget resend keeping Business Apphcations 2 3 4 5 Scientific Appacations 2 3 4 o iardwase Upprades l 2 3 4 P ogsamming Languages Feds I 2 3 4 S Pogsamming Ntarwals 2 3 4 5 Peripheral Devices l 2 3 4 S Fer any ef the abore which yeu ranked 4 herer please denirhi specifically the types of peograms or predvels yeu weuld diid usetud Ep if you want educational soMware what ania Rade level type of progsam would YOU like to see How do you use your Interact Q Playing Games C children s Education CO Exteenat devise control _ Business Record Keeping E Learning te Progiam O Programming uama C Personal Record Keeping C Acess to Other Computer Systems Seene tnatysis C Oter please specify Do you program your computer Lives Cne it do Yau use CT easic Machine language C assembly language C Other please specify What sort of propa ms do you create How many fours per week ts yaus Compuier in use Are there any particular areas of programming ha interest you arid that you would like to have mee information a
179. ly lists all gear posi tions in white When he shifts into gear by pressing one of the buttons on the nutihoard tha appro priate word lights up in red on the menu letting him see at a glance which gear is in use In all more than 4 different functions are controlled in this manner One of the major reasons we chose the Interact for this project was the character size on its screen display Don states I can read the display without squinting which wouldn t be the case if I had useda computer with smaller letters Eat Your Heart Out 007 Bond would feel right at home if he could see Den s car at work in an aute show like the World of Wheels Don s fiberglass creation sits on a ro tating platform while the Interact executes a program that shows off his handiwork The roof mounted on hydraulic lifts moves up and back like an airplane cockpit The hood is also lift mounted and opens to reveal the spotless engine Lo nothing dazzle lights as Don terms them are continued en page 4 i ae 5 od Ty pl i ti peu Fis ib 9 a hh hes A mt N fo 2 re eae ai i i a bei Bie Man a oh Tidal ae ds z bal T ar e te et i ag a ke ef a i Lhe aen E TEER a g jh hy Milk i i f a fp be d gt j Lo iir 7 sid a i Pi 0r oy ee ee ee a t Vio we Dear Friends Summer is a lonely time for Inter acts They get locked away in closets or stuck on shelves forgotten wh
180. ly those new features you want You can of course make these changes to the l6K version of Microtext You ll lose a little RAM in the pro cess but the amount of text the program can handle won t be dramatically affected If you re operating on a 32K system one thing you ll definitely want to do is create your own 32K version of the program Having to run the program through the 32K Translator cach time you want to use it is no fun Creating your own version is easy Just load Micretext then the 32K Translator Answer RS232 BASIC when the Translator asks for the originating language When your program has been converted to the 32K environ ment load Microsoft BASIC for 32K RAM Incorporate any of the extensions given in this artrcle that you wish then usc CSAVE to store your 32K Microtext program on tape To modify the 16K version just add the patches using RS232 BASIC then CSAVE the program The Personal Couch Our first extension adds a new processing directive Z Z works just like T in that it requests keyboard input for inclusion in the printed output But whereas T processes the keyboard input by putting it at the beginning of a new i ne Z embeds the user entered string within the body of the text This can be useful for personalizing boilerplate letters or standard contracts such as leases ex sales agreements To implement the Z feature add the fol lowing four lines of code 600 READ S CS MIDS IS 2 1
181. m municate with the sooo in the Intevace community ve included asuryvy form with thes issue le s the anly subscription price to the newsletter Let us know what you like dislike and nead to make your computer betacr for you If you have Guarlons now is the ideal time to ask If you want soshatean idea or program by all means send it along If you know other Intevacr owners that are not getting this neustercer do them a favor and send in their names Right now the form of chis publication is loosely defined What will emerge as ics final form will be UP TO YOU Maw L24 Marv Long Editor Product Notes En each issue 1 Ilinclude infoemation on new soitware hardware and publica tions from Micro Video These will nor be ceviews per se as rhat only gives you one person s personal opinionofa peod uct Instead I ll give you an expanded explanation of the products so that you can make your own judgement as to the product s worth co you This issue s PRODUCT NOTES features the new BASIC manual BASICALLY SPEAKING Undoubtedly the mose requested item at Micro Vi eo has been a new BASIC programming manual Well it s finally here A real doorstopping 200 pages of information on Level I RS232 and the new Microsofe amp K Graphics BASIC EDU BASIC is not covered che book has I I chapters and 4 appendices Actually though it s functionally in two parts The first pares some 120 pages is a tutorial on t
182. m that did something very useful in a very small amount of code The other candidate s program wivle oot terribly useful really explored new areas of the machine The obvious solution to tts query was to awatd two prizes So may have the envelope please the winners are LARRY JENSEN of Annandale VA ANTHONY WATSON of Woodland WA for his Pocket 7 Calculator for his amp color scieen display The Keys to Success We cant promise you li never make another programming error We can promise youll make fewer typing errors while programming with our new professional guiality ke board Designed for Micre Video and the Interact by a well known and highly respected keyboard manufacturer this kevboard is similar to those found on Apple Atari 800 and other computers The colors are even ceor dinated to complement your compu ter s case Designer keyboards What next les ight grey keys have dark grey legends for high contrast and easy readability tia handy feu ture for those of us who graduated from Hunt and Peck U Sturdy and compact this 53 key standard typewriter style keyboard fits neatly nto your Nleract s case jn place of the ald push button board Installation is a simple maite The Professional Keyboard Kit con tains little more than the kevboard assembly and plastic mounting ring The keyboard and PC board come assembled as a single unit so you dont have to fuss with making sure you get al
183. magazines most of which are written to the 6K standard Many of those programs are woitien for the TRS 80 so we thought you might like some hints on translating them to our environment Before you start lo convert any program make sure it requires no special hardware such as printer or disk thal you don t have Also look lo sec if the memory reeuirements fit what you have Go through the pro gram looking for unfamiliar com mands and check your BAS CALLY Sf EAKING maybe BASIC has that command and you just don t know it Try to follow what the program is doing cach step of the way If you can t get a part of it to work sec if you can come up with an alternative way of handling the operation Aftera few tries you ll find that you can usually determine which programs can be translated and your job will become much easier Meanwhile you ll learn a lot about BASIC One of the first differences you ll encounter is in line length Since TRS 80 computers have a longer line length you may have to put the oper alion in multiple lines on your com puter Then there arc differences in raphics The TRS 80 graphics screen is 28 on the X or horizontal axis and 48 on the Y vertical axis and they sy our machine has low resolution That means that their full screen pic ture will not fill our screen completcy Also the origin of the TRS 80 screen 0 03 is in the upper left corner just the opposite of ours Their plotting
184. mptesed game and resume play later In the personal eomputer world adven ture gemes rank among rhe most popular ever Gevised and it s no wender They combine what most ceripueerises like hes che neecssity to strike out and ex plore new territory and the requirement of using brainpower to win It s not a question of how fas you can reacc by pushing a button or lever but rather how well you can think If you like puzzles you ll find the TROLL HOLE ADVEN TURE will provide hours of absorbing entertainment for you and your friends GOOFY GOLF 1 or 2 Players The newest machine language adaiuon co the Micro Video catalog is GOOFY GOLF which pucs the lively entercain resulting i in ai chie one fom cask 24 95 OF rom Micro Video 19 95 When you order the unit from Mieto Video a f sample demonstration program to get you Started is inclided Contact Micro Video fora Votrax flier and further details A great Christmas idea for the e ceiu nut in your family Nee eee ee nee ment of a wolf on ae TV screen The game has 18 derent holes and you can play the front 9 back 9 or all 18 hole is a maze ef hasards and barticades and angle show are sometunus necessary 30 maneuver around rhem much libe shooting pool If you hit a blue water hazard you lose your bal and have to wee off all over again Red mystery hazards randomly move your ball to a dif ferent part of the playi
185. n future purchases What are the actua mechanics involved in pro gramming It depends both on rhe rogram andchoiceo pto grammer Some pro grams like COMBAT were entered directly into the Interactin hex machine code Others like the Troll Hole Adventure were writren on another machine in assembly lan guage and transferred to the Interact Most of our in house Programs are written onan larel Devel op ent machine in alan guage ctlied PLM OK You have the program written and evaluated Whar comes next Testing Far usability of course but mest impor tantly fos bugs Then afzer it s rested it must be fully documented This job falls on Cori Walker Work ingwith the program then explaining it in a clear concise mannet can take some doing Then you have to produce che software for distributien How do you copy tapes would think that would bea CCMLCONSUMLIRE POCE Actu lly ic doesn r ke that much time We have the specially constructed tape stand thae Interact Electrons originally used and can make QO copies at a time Computer Hold ing Company also used our equipment to dupli cate the tapes they dis tributed so our equipment is really the stondard against which duplication and alignmencis measured What s in the uwerks Can you tell me a little about thot want to be careful not to make promises until each pe gram finishes its eval uation There are
186. n your computer Many printers can be set up to run with either a parallel or serial interface but the Interact s RS232 is compatible only with these rial type Depending on the printer you may also have to adapt your The EPSON MN 80 printer cable lo the apprepriate pin configuration for data 1 or you may have to set switches within the printer itself for correct operation We ve worked with a number of rinters on the Interact and also ave had feedback from users with various models The foltowing discus sion of printers is therefore based on our direct experience with them as well as information and opinions supplied by others Epson Printers There me many Epson printers to choose from virtually any of which could be used with the Interact We ve selected three of them for discussion the MX 80 MX 100 and FX 80 The MX 80 is a widely known printer it is perhaps the standard by which other printers ofthe same type are judged We emptoy them almost exclusively here at Micro Video and definitely recommend them as they are reliable and fast The MX 80 is typically priced at about 550 but with the advent of newer Epsen mo els you should be able to find an X 80 on sale for as low as 289 The MX 1 00 is a good printer to consider if you need wider printout of information such as financial state ments or spread sheets It is basically the same as the MX 80 except that its maximum print width is
187. n his BASIC programs 10 CLS COLOR 0 3 2 1 PRINT CRRS 8 FOR T 1 TO 187 PRINT CHRSU1 NEXT AS INSTRS 1 The INSTR function in the line mevely holds the resul tant display on the screen for viewing It would of course be removed when this grid is used in a game program o J pyy Far a m TTT i a erT amr T oe amu Pal a Janae ee bate Fo Tine n iee m e a oai e Eee T E T e eee a e ares ay i e ie eae An s mia pa Fa 2 o se oe Ce C ms m Sia i Enu nu ga Dae in Se e m ap e l i e E a es a os m ea E daim s o a n Hena Coming Next Issue e Computerized Corvette Stingray Bulletin Board Moving Pictures continued Selecting A Printer e New DiMensions in BASIC e Hardware Hints Video Out Mod s 2 i Lae m a B rg 7 4 a o_o E 4 a a i a a lt a a aa a k r 4 pe a af a B T oe one z ia z ate rou a F pr jii i i a gt r a u m p a 2 i ree Oe i ae z zi pgpnnn a a on ma zH i ee oo al I 1 a m at P Tor m Bk x F a tate E i a4 VIDEO Fall 1983 Computerized Corvette Stingray What began seven years ago as a simple body repair to a 1968 Corvette Stingray has resulted in a computer contrelled vehicle worthy of James Bond About the only thing missing is a bumper concealed machine gun You might say that Don Stockten a Ft Lauderdale based boat canvas maker went a little overboard when he be
188. n the standa djoystick he wi edin the various parts He says that the problem with the controller is that it works se much belter on the games that he had to go right eut and spend another 36 to build a secend one Better Better Mousetrap Mare Wilson of La Mesa CA says he has a simpler and faster solution to the problem of maintaining amp preger m timer while accepting keybemd input than the one offered by Albert Narain of Helland last issue He states that it is faster be cause it doesn t use the 1 G function and that it will icad any kev including CR shifted and control keys with the ex ception of LOCK You can determine whether er not LOCK is in effect by PREKI24530 a value of 255iFF means lock is engaged while a value ef 0 Means it s disengaged To disengage it POKE a value of 0 mto that location IO POKE 19215 25 A AD 24528 CHx0 20 IF PEEKAD O THEN Cit PEE RIAD 1 PORE AD DAS CHRUGHO OF CH gt 96 AND CH lt 123 THEN CI CH 32 A CHR CIO 40 REAN A A B 8 A B C d Woedward of Sun City AZ was quite confused about the operation of his BASIC program His idea was to identify and reper mtegers between l and 50 that equal the sum ef twu suares 14 1O PRINT INTEGERS THAT EQUAL THE SIM OF TWO SQUARES PRINT 20 FOR N 1T0 50 30 FOR Axl 10 40FOR B 1 107 S0 IF ATA B B lt N TIEN 80 GOPRINT Nee ACA B B 70 6070 95 D NEXT B 90 NEXT A 95 NEXT N 99 EN
189. n the screen was Sue s name and age superimposed over a video birthday cake complete with flickering candles Need help Catt 313 996 0626 A First of all vou ll need an RS232 interface for vour computer which you can get from us and easily install yoursell Then youll need to select a printer Many different types are on the market now with a variety of capabilities and price tags Youll want to choose the one that fits your processing needs and your budget The only requirement the Interact has ts that it be a serial or RS232 compatible printer We ve tried a number of printers and our favorite is the Epson MX 80 tor MX 1 6 The third ttem you ll need is a cable so your computer can talk to your printer We don t stock print er cables because the required pin configurations on the cable connec tors vary from printer to printer Commonly there are differences be tween the data lines used for send receive and busy ready signals We do make custom cables on request although you may prefer to do tt yourself Our RS232 documentation details the Interact pin configurat on and instructions for your printer should inciude its data transmission requirements ty Okay who s the wise guy Sue asked a little red face No one confessed Each of us applauded Tom s handiwork when our separate orders were announced as if we all had our own personal elephants up on the screen Soon we were mu
190. nching on the hot mouth watering pizza At that point it didn t matter why we were there We were all having a great tim As we ate we found om eyes con stantly returning to the eolorful ac ttve screen We saw several more announcements of Sue s birthday and a message welcoming Micro Video of Ann Arbor surprised us as it scrolled horizontally across the bright red owl logo which appears periodically in the display A multi line advertising message sur rounded by an eijght color scroll announced a food special for the fol lowing week And another screen that appeared frequently which was especially handy for the couple of us who got absorbed tn video games and missed our order announcements displayed all orders that were ready but hadn t been picked up As the day wore on the fatal flaw in Dave s plan became apparent He didn t know how te trick us inte re turning to Ann Arbor ray A programming language ts pob ably the hardest type of program to test Thats because there are so many variables so many wavs the different parts of the prugram can be combined and used A thorough test generally requires months of steady usc na num ie oSapplication areas Many of you who purchased the Assemblex Editex package have been disappointed with its perfor mance Frankly we hnven t been too happy with it ether There s been a direct correlation between our programmers aspirin consumption and th
191. ng GOSUB and GOTO is generally con sidered t be good programmin p actice but there s an exception 0 every ule For absolute speed cut therm 7 Use PEEKs POKEs and masine language subroutines If you re learning langua gt pat that smal subroutines can help speed up a game withoniya small amount of otk A good example of this is the BOMBS AWAY Program Well there you have it Let us know how you make ut Excuse me I ve got an enemy saueer at l2 ovlock hight E br E O I F aS eS Se es Ee ee Se ee ee Sees ees OB Eee FASTER BASIC One technique to make BASIC pro grams tun faster is to use subroutines properly Microsof BASIC calls mus hunt for the caquested subroutine and che interpreter always star looking at the beginning of yout eode That being che case che most efficient way to write yow propams is to Place the starting gt ISITUTOns user inputs andin malizarion eode in a GOSUB or GOTO coward the end of youn program it s on ty accesmexi once at start up 30 OU can afford to lose the initial speed Then place you most used subioutines toward the top of your code Then when you cal that routine BASIC doesn t have to look veiy fai to find them and the operating speed will be fasier Not convinced Try these two shon programs The fitst labelled POOR PROGRAM has to go to lin 1190 to find its subroutine The second labelled BETTER PROGRAM has two mote lines yt it exe
192. ng chair men of the boacds of several Fortune 500 corporations de own and love therr In veracts they re used primarily for enrer tainment pucpeses not for serious busi ness applications Inseract did manage to get a Mod net work of dealas in place and machine sales went pretty well Unfortunately quality control was a weak link and the early machines had an abnonnally high failute rate By che time Interact had machine reliabilicy problems more or less solved the dealers as well as a lor of individual customers had been soured The hardware was basically seund and there was a ceasonable cemplemenr of software but the Interact name had been besmitched Equipment reliability or lack thereof however wasn t eompleteiy responsible fer Jnteract s poor repvration Interact Electcenics provided vircuall y me support for the machines once soid I don t believe they ever mailed new product an mouncements to owners for example Documentation was definisely subsran dard the old Level N User s Guide which J assume most of you have eeen was the only ptogramming manual available Ie was put cogether in a hurry and was useless for all but che most ad vanced BASIC programmers PEEK POKE and USR were nor documented ar all Interact liked to pretend chat they did not exist in Microsoft BASIC for che In teract as they were paranoid abouc soft wate piracy For that reason machitte language acess was also sotely deni
193. ng field sometimes good mostly not Two holes even have gates that open and close requiring earcful timing eo ger the ball through the hole Voie can move yout cub anywhere on the sourse to hir che ball When youve positioned the club you press the fire bucton to serike the ball The farcher away from the ball your club is the harder the hir You cat the efere putt softly woward the hole or smash the ball and send it caceening around the playing field Our sesvrs tell me that GOOFY GOLF while not as flashy as somegames has long term playability It promises to remain entersmaining leng after other games besome dull a BY Well all you BASIC bulbes its che Bate tines or less Send te Micro Video tle of the Byte again This imne has some ATIN SMALL BYTES The pogrom interesting Small Byaes submiceed by In selected best by aur panel of judges will ceract owners Try chese on for sise aad win 50 00 in product credis from Micro if you haven already sendin your try Video So give it a squeeze and send it Remember che rules are to write a ro on gam using any Inrerace BASIC in thres Bill Doyle of Manchester Michigan provided this noisy and colorful Level I program We thought it sherdd be calied Invasion fom Outer Space He said his wife called t A POX ON YOU 20 CLEAR CLS FORJ 1T03000 COLORD 1 2 4 30 SOUNDO 24844 C J SOUNDS 200 J SOUNDS J 40 C INT RNO 1 77 B INT RN D 1 112 D
194. nius Twelve yearold Drake Diedrich of Gig Harbor Washington submitted these musical bytes Level Il 100 CLS READA FORB 1TOA READC D PLOTB 3 20 60 C 16 D 1 TONEC 9000 C D NEXT 410 DATA18 133 4 133 1 99 2 133 199 1 79 2 133 1 99 1 79 2 133 1 99 1 79 120 OATA2 99 1 79 1 62 1 79 1 99 1 133 1 RUN Elmo Ferguson of Mima Fimida came up with this onedows which he rimad Micro Boogie Woogie Le i nm all the way duough wo get the rhythmic effect 10 FORX 4T04100 SOUNDO X FORY 1TO2Q NEXTY NEXTX From Steve Smith in Dearborn Michigan a program thar illuserates 8K BASIC ac its finest You can use Control S to freeze the program action and seedy the intricate pattems 10 CLS FORJ 0TO7 COLORJ J 1J 2 Jg 3 20 FORI 1T077 PLOT56 1 2 1 2 1 1 PLOT 16 40 1 2 1 1 1 30 PLOTS56 1 2 77 1 01 1 PLOT94 1 40 1 2 3 1 NEXTI J GOTO10 won t bad Wha hada I do Tape loading faifures can result for sevetal ressons First there s A ditt Keep your computer s tape head and capstan clean wich a cleaning sape or eommercial cleaner from your local audio store Secondly yout gape head may need realignment Micro Video has an a ignmenc bit available fer this purpose and every Invecact owns should have one The third reason a tape can fail to load is that it is defective While the reliability of Micro Video eapes is geneally excellent an octasional bad tape does get our Mico Video warrants thei
195. not to say however that it can t be a similar type of game An action space battle for in stance should be signfi cantly dif ferent both in graphic display and operation from software already in our catalog Does the program have a pro fessional appearance Compare it against other software we sell Leok at all aspects of the graphics color combinations speed and smoothness of motion and design Color combi nations should be pleasant and easy on the eye Moving graphics should not flicker Also pay attention to the general appearance of text in your program evaluating placement on the screen readability spelling grammar and consistency Does the program appeal to a broad audience Will a wide vari cty of people be interested in playing the game or usmg the program A program that is so specific in nature that it will interest only a select few users is sust not suitable for our small marketplace D esthe program have enough features and variations to give it long term playability Our best games are those which a child can enjoy but which increase in diffi culty during play or have selectable skill levels so adults are challenged as weil is the program a logical com puter application Not all activities adapt to the computer en vironment A program that lets you plas a solitaire card game is an ex ample of an illogical application What advantages vould the pro gram have over a deck of cards
196. odilica tions required Yes Virginia there ts a use for that empty ROM sockct The Stringy Sponge stores files by number and can hold up to 255 separate files within its memory censtraints You ac cess the system with a USR call from BASIC programs in direct mode or from machine language and you can call the commands READ WRITE REWIND FF WD and CERTIFY This product will greatly enhance the capabilites of your computer and coupled with the 32K memory expan sion will allow for truly serious appli cations TO use the new Sponge you must have a Micro Video RS 232 continued on puge 8 Lester From the Ecdit r REMARKS Your computer just keeps getting better and better remember just a short time ago buying mine and then flinding out that Interact Electronics was going out of business bought what software I could tben afford and tried to get all the infomation that was available The lady at Interact tricd to be helpful but she just didn t have that much The one thing she did give me though was a telephone number of a guy she thought might be able to help me That fellow was Dave Ross and his company Micro Vidco I went and talked with Dave and he indeed did have information and sofi ware not available from Interact Electronics Remember at this time we couldn t even POKE or PEEK in BASIC Machine language was but a forbidden fantasy Shortly after that first meeting Micro
197. ood idea to do these POKEs first These POKEs ate unnecegsaty in Microsoft 8K BASIC as the limits have already been taken off POKE 24581 1 POKE 24582 140 POKE 24583 105 POKE 24584 197 POKE 24585 195 POKE 24586 224 POKE 24587 102 Now hit RESET R and your ptogam will state up automatically You can algo place these POKE seateme its into a small initialization program and run it before you lead in your BASIC program Try it you ll like it able co sartsfv every request We rry to be as responsive as poss ble however and to keep the cost of out products and services reasonable As Maty said in his REMARKS column though Interact Owners must understand that our support can be free We ve got ovezhead rent bills payroll supplies ete Although it s gracifying to achieve custemer satisfaction by helping ouc with quescions tepaits and new products customer satisfacrion alone doesn pay the bills The borvom line is that supporting the Inveract market means losing money we ll discon tinue that support and pursue our com mercial applications exclusively We re probably the Intezact s mose ardent en thusiasts so we Gon want that to hap pen We hope you don t either og fort eenggenenecee alpine oa a oe E EE m m gt bs laa a SS S A eso t Nees sc eee eS a o o a Fp If you re new ro BASIC programming mysteries surround you waiting to be
198. otks What s your vote Which one of these pro grams made you say Oh wow FAR OUT ES Dear Micro Video Thank you for hanoring the coupon for the keyboard and the AL deal After mv last purchase in November 981 l didn t hear from MV l assumed you were no longer in the business of supporting the Interact Pm glad yeu still are and the best of luck Sincerely Martin Gilbert Milwaukee WI Dear Micro Video Greetings l think your suppert of the Interact is fabulous I own two of them The new keyboard is fantast ic now if we had ROM BASIC The Computer Doctor is great lhad one computer down and ome got the boek it teek 20 minutes to get it back on line a bad voltage reg ulator Keep up the good work and keep the programs coming Gerald L Reno Wurtsmith AFB Mi Dear Micro Vidco l have enjoyed the RAM Pages have and look forvard to receiving mere Keep up the good work Lasi but certainly net least be sure to send Sue Denim with my order I know you probably have had a lot of people tell vou L want you but hope lam the onty one to tell you to 3nd her eut here So for that reason my request takes precedence ever all others Thanks for your help to the Interact community Sincerely F anklin Sev ser Rivesside CA Deor Frank Sor but all our boxes are the wrong size Besides get claustrophobic Also who would da RAM Pages if were there Sue D
199. over a secret passageway You might DRINK LIQULD only w nd it a deadly acid or the water you need to extinguish a fite in another room You never know what will happen which mabes the game a teal adventure In the TROLL HOLE ADVENTURE you venture inte a troi s cave try to locate and remove the hidden treasures sentences were TA ER berish The Apple L Plus it Girns out isn t equipped with the proper handshak i Amazingly enough the Interact bested When Micro o Video tried to hook up their T N T toan Apple I1 Plus the result were erratic Sometimes words and sentences were clear b t frequently letters words and the Apple on this one below Votrax s list price of 375 Infor mation on cable wiring is included for the do it yourselfers in the crowd You can even wire a dual hookup to tise the T N T and a printer at che same time If youd i rather 1 not t wire the eat Trea yow Fani h Interact INT Coneis u with 3 yonr computer ith the Vorrax Type N Talk protocol in its RS232 interface ta han dle the T N T as is another communica tions interface is requited p The Votrax Type N Talk can Be dered from Micro Video fot 359 fer a maximum sexe of 100 points It takes hours even days or weeks to solve the puzzle completely so the program has a built in feature that leas you save a par tially co
200. ow how to squeeze your bits If you re pro gramming in BASIC see the more than 20 hints for shoc horning in chapter of BASICALLY SPEAK ING The game should have an eacder standable objective You should be able o state the basic idea in a single sen tence that an 8 10 year old child can grasp While the supporting rules and strategies may be significantly more involved a player should be able to getthe point of the game by watching the play or from a brief verbal sum mary A game should have e set of clear instructions built into ic if possible as RDOM E IN S AAA OT OR RUNS Scrar frann on aprig game well as detailed wiiiten documenta lion Viewing an embedded instruc lion summary should always be op tional repeated enforced display of instructions quickly becomes an iri tation to the player who understands the cules of the game Usc a clean concise style with word placcment on the screen thal is visually attractive Be clever the insltuctions should act as an appetizer to the main course of the pame If you re crowded for space however the em bedded instructions should always be the frst to go Don t ever sacrifice graphic effects variety or program operation for insinection serens You can always document the rules of play on paper You can t document how the sereen would have looked what message would have been displayed or what other game featu
201. pabiliries point of was the TRS 80 As Rew capabilities were added eo the original desim such as a keyboard program ming acc s RS232 and ROM BASIC add on production costs increased In Orde to keep the price low the designers cook a number of short cuts This is fer example why your Inte act has no built in character gene ator i Still ic was and is a nice little machine By the time Interact got round to selling it however cheir resources and finances were severely strained With all che money invested in hardware devel p ment there was littte left over for effective marketing As Frn suce you know you can have the b t p oducr in che world iteract Electronics ECTIVE FROM CORI WALKER but if people don e know it exise3 you re not likely ro sdl many Interace s marketing efforts were plagued with problems fom the start frem what Ive been able to piece together They had a relatively high turn over in markesing pexsonnel As nev pto dle with new ideas became involved the marketing straecgy would change re sulting in no strategy ever being followed through to iss logical conclusion Fox ex ampte the Interact was atone Me pro moted in such places as the Wali Sreet Jewnal and toured as a computer for the business execurive This was especially ludicrous piven that most of the software available at that time wes sataly education enterrainment oriented Whi a number of executives includi
202. partment number If we have your correct ad dress and you regularly arent re celving these materials we suggest that you complain to your local PO That probably won t locate what s missing but tt could help ensure de liveries are made in the future Ifal else fails call us and we ll send another copy first class Q I d like to hook up a line printer to my Interact but m notsure what kind to get or what other equipment I need Can you give ine Some advice ow orders to begin appearing on the screen Here comes the first one Dave informed us Before us some of Tom Matulevich s programming magic came to life His intricate video elephant a rendition of one of the stage show characters moved fluidly from the right of the screen to the center t stepped and shot a blue spray of water from his trunk As the water fell it dissolved into a bright yellow order number this time number 57 over the words now serving We all applauded Tom took a bow and everyone around us wondered what the heck was gotng on At this point Dave was sure his plan was successful beyond his wild est dreams Not only had we seen the display but we were enjoying it im mensely Hey that s my number Suc bel lowed with the enthusiasm of a 10 year old She headed toward the counter I know your order s ready but picase wait just a second before you get your pizza Dave asked Good here it is U o
203. pe volt ohm meter and other fancy equipment until they find out what s wrong Which brings us to the topic of re pair charges Several of you have asked about repair charges so we ll attempt to de mystily them The average repair charge runs anywhere from 415 to 70 says our Customer Service Manager Dallas Maddox But there are many excep tions Some prohlems may cost only ee ie ee oe eee Sao ae A 2 the problem may be just a capacitor which could only be detected by an os illoscope About the only way to tell for sure is for a qualified techni cian like Tim or Ed to examine the Flint da I repair ieee Eadie cetri me nays Bdand Frm perfurns ruutine te rn foe PENNE chr a xtefrsteceetiad ntn ber of YA upatractes 20 to fix On the other hand if a power surge has blown a number of circuits in your computer the cost may be substnntially more The main problem with trying to pin down repair prices is there are so many variubles involved This is true of any electronic component such as your tclevision or stereo sys tem or example suppose your computer is missing a sound or sounds You may think the sound chip has to be replaced However Hardware Hints vm The Pause That Refreshes Have you ever been in the middle of a serious game of Hot Rocks or Alien Invaders and the telephone rings or someone knocks at your door How annoying There goes the new world s record yo
204. player to sare game status and deta on tape in lengthy strategy oriented games such as an adventure or board game Players may want to conunue games over multiple playing sessions of to review their play at a later time Stinplr fy restarting at the conclusion ofthe game The player should be able lo choose to play the game again by pressing the fire button or the key Use PLAY AGAIN Y N and SAME GAME Y N restart formats to allow player to respecify game op lions if desired Al ac time should a player have to reselect game opu ors to play the same game over again Game Options An important feature in program operation ix allowing the player to contro some factors in the game Multiple skilly levels should be em ployed ta let the player decide the dif ficulty level at which play ts to begin These can he implemented in different ways You can let the player select from a range of levels cach of which has limits determined by the program logic Or you can let players specify the variable scttings of certain game factors and use those setings to de fine the skt level and game pla This method provides more flexibility and a larger number of skill level combi Nations in the pame than does the first method The lowest skill level in the game should be easily playable und beatable by novices while higher levels may be nearly impossible to win Inclusion of multiple skill evels IN a game is important becuuse it
205. players hands The shell movement c lculations plorang and polning which BASIC does rapidly and well under its own control can 0 on without having to check for user input A ficther feeling of action can be generated by real time decision In Bowling fox ex ample the playing specd eomes from t y ing to release the ball at rhe right time not on its roll down che alley The player has no control over the speed of rhe ball only on the poine of release The object becomes to calcul se che proper time for release 2 Limit che number of tems in mocan at any one me Each separate movement slows che speed by one half 3 Use SOUND statements instead of TONEs Die to the way a TONE is made veryehrng must stop vanl the TONE c mopleres S unds on the other hand can continue indefinitely and don t halt operation of other funcn ons 4 Write aght Don t do things twiee if onee is enough if a routine isnt necessary LEAVE IT OUT S For graphic cokens use CHRD You can make you own pedal Aaraaps 3o use with CHRS See the POKE staremenc in GASICAILY SPEAKING o Lr Ovwom s Leap for Life for ivfosmacior on dog chis If you must draw use Microso amp 8K BASIC its graphics are up a 30 cimes faster than level U s 6 Write straight line Avoid using GOTO and GOSUB statements unless absolutely necessary As discussed in FASTER BASIC they force BASIC o search through your code and thus slow down operation Yes know that usi
206. profes Lea keybunrd We ve tried em both and they work well They are as Follows Fase Scroll toy 8K Graphics Level 11 BASIC 20 POKE24864 1 POKE2 4838 192 30 FORM 25264T025284 AEADP PAKEM P NEXT 40 QATA33 32 73 62 2 245 62 143 54 0 SO OATAIS 61 190 184 98 241 69 1949 181 98 201 00 FORM 248511024862 READP POKENM P NEXT 79 DAIA206 176 98 0 0 06 0 0 0 0 0 Fas Sevoll for 32K SASIC 15 POKE24861192 POKE2 4857 1 20 FORM 284081025426 30 READP POKEM P NEXT 40 0A1A93 32 73 62 2 245 62 t43 4 0 35 61 50 OAIA194 72 99 241 61 194 69 9 201 60 FORM 248447024855 70 READP POKEM P NEXT 80 DA1A208 64 99 0 0 0 0 0 0 0 0 0 Distinguished Characters n addition Bob Alpert submitted a program that lets you distinguish between upper and lower case letters on the screen when using Micro text Upper case letters appear in white and lower case in green With this program any text in data state ments will be lower case by default 1 Load 32K BASIC 2 Lead 32K Ver sion of Microtext Sce page 13 Fall 1982 RAM Pa ges to see how to create the 32K version of Microtext 3 Type in the lines listed below 4 Run the program Any data statements con taining text to be processed should be enter cd after line 110 Bob says that no RAM istakenfromthe program area because it resides in the space sct aside for USR routines We found this Microtextex tens ton to beextreme lv useful Here s his Distinguished Characters cede
207. r catalog From new en RAM Pages wen t get bumped fer more im pori projects because we wen t ave mere important prejecle RAM Pages will move te the head ef our list You ll knew when to expect each issue Also in the next issue we are insti tuting a new Bulletin Beard sectien see page 6 This will allew subser1b ers to communicate directly with other Interact owners free of charge Has your line printer gone to elec tronic heaven and youd like to re place it with a used one Want to trade software yeu ve written with ether ewners Want te find out who has been able te computerize a het tub with an Interact RAM Pages subscribers can get answers to ques tions like these and mere Please just den t uy to sell your Kawasaki threugh RAM Pages Fach issue of RAM Pages centains coupons for generous disceunts en Micro Videe progucts For example be sure to check out the cataleg sup plement included in this issue for some intriguing new software Yeu can take advantage of the coupons on page 19 for these exciting new prod ucts or any from eur prier catalegs We will alse continue eur popular contests fer Tree merchandise There s a new graphics contest on page 15 and we expect you ll have a lot of fun with it Get a suggestion for a new contest Then send it te me And den t ferget eur standard fea tures The Cempuer Dector will tell you what to do when yeu dump beer down the tape drive Feature steries
208. r program capes for 90 days from pur chase lf dwing this warranty pertod your pe fails 3o load you can return i and chcylf replace i wich a copy of the same progam at no charge Realizing that tapes can simply weas oue with exrendad frequent use and thae this won c always happen during the wartanc period Micro Video has established a nadein policy You can return a defective cape that is no longer under warranty and they will replace it at 50 of the list price You can do a lot to protect your tapes ageinse damage and failure Keep them clean and dey Storing them in ther plastic cases will pretecr against dust and static dischacges By all means keep your fingers off the exposed portion of che tape Keep the sapes away from extreme hea and cold And dont puc them near magnets or magnetic fields this includes putting them on top of the set of speakers Finally if eapes consistently fail o load America One of my Micro Video capes you may have a hardware pooblem If you ve exha seed all other contingencies you can send your uret into Mieto Video r repair Q Whar waly is ROM Rom means Read Only Memory These chips are firm ware and have software more or less petmanencly insealled on them Fhe program stays in the computer even when it turned off and is automatically avaitable when the com purr is turned back on Read Only Memory means you can read from it bar cannot writ eo it The ehip is
209. re then used in subsequent references to the data in the matrix making manipulating and reporting the data convenient and self documenting When you ve entered an initial set of data you can perform a number of operations on it In the VideoCalc documentation our hero Joe Alonzo types in only five columns of data for ten rows into his 13x18 cell matrix then uses VideoCalc s CAL CULATE function to compute val ues to fill the rest of the matrix The program also has functions that let you change the data as needed pro duce sorted reperts on all or just part of the matrix plotyour data graphi cally to analyze trends and store and retrieve data via cassette tape And if you want to perform compu Olvissawas SALES Iv Buia Jat alo CS OL AN 9 4 BQvie an mE Dison Cubist ar tations on your data ihai are too complex to handle with the CAL CULATE function there s even the facility to formulate your own func tions VidcoCalc can manage datain matrices containing up to 2 500 cells that s a lot of numbers Although you can name the rows and columns for essy aceess to your data VideoCalc is capable of manag ing aurreric data only If you need a program that will let you keep rec ords that include string information as well such as supplier names or item descriptions then that s a job for DREAM DREAM DREAM an acronym for Data Record Entry And Management is most useful for keeping your dat
210. re printing costs but mere typesetting charges more graphic arts cests and mere writing time and time is something eur staff has precieus little of I m sure there are several other increases Fve fergotten Since we dent carry advertisements for Vic Tanny or McDonalds I can see it new Micro McVidee we have to absorb all these cests from our general business rev enues One optien which wasn t dis cussed fer long was to go back tea mere affordable 12 page format But that weuld be ceunter productive We wouldn t like it and we re sure you wouldn t either We are cemmitted te supporting your machines Fewer pages ef inferma tion in our eyes translates to less support for the Interact This goes against our basic nature here at Micro Videe So since we aren t backed by a conglomerate with end less financial reseurces we believe this is eur best cheice in offering yeu eur continued support That s the bad news Let s take a loek at the geed news all the good stuif vou ll get fer vour 20 per year First of all you ll get four infermation packed newsletters at predictable times Raise your hand if yeu ve been wondering when this issue would hit yeur mailbex Getcha didnt I Ameng ether things 2 when you cemmit yeurself to the 2 subscription price yeu get an in creased commitment frem us The last RAM Pages was mailed in Oc tober nearly six months ago partly because we had te produce our Winte
211. res might have been present had the internal in structions not been included You might choosie to document via a demenstration tale which can oper ate as a user selected option or which plays itself when no player is pre sent Arcade games usc this approach to provide visual program instrictions and also to entice a viewer to become a player ani ale on the type of Q game youre developing this ap proach may even require less memory than displaying text screens Flawless operutiun ts a must There should be no hidden bombs that cause the program to fail Test all your contingencies keeping in mind thas first time users especially will tend to iry todothings that o you might seem totally illogical This type of testing usually requires several hours play by different people at different skill levels There s nothing worse than having a game abort unexpectedly in the midst of an exciting segment or after a long time investment in play has been made Plan Cor these seemingly illogical player moves with data checking Al ways check inpuls trom the player and evaluate them Don t for example allow any response but Y N or depression of the fire button to a vesino decision in z game Make sure the player s data fits what is to be done with it Embed error messages in your program if possible to let the player know what s wrong The game should have respansire action fF ihe program offen accept
212. riter LA36 dot matrix printer To begin the process he attaches a photo or other art that he would like to reproduce to a seetion of printer paper and feeds it into the printer He then uses a BASI IC program to move the photoresistor across the page and race e light intensity of the various sections of the photograph h the program stores each line on tape He inptts the dig mage via tape back into the computer one line ata ae e printer reproduces the image using characters of var yin intensity The prom am al ows hi to adjust contrast in the image by a power law intensit Roe ae Murua om a tion He uses a 18 character gray scale ran space for white to an H oversee for black Dave says digitizing and printing steps for an 8 10 picture each take about 45 minutes at 300 baud He sayy he can even produce a negative image E CARBA oe ONGC DEV ES 5 M 20 DATAS 32 39 32 33 32 43 32 48 32 56 32 47 79 43 79 42 79 72 35 40 FORIFOTOM 1 REAOC 1 0 I NEXE 100 CLS 130 INPUT O OR P A 140 IFA 8 GOTO200 ip IFAS P GOTOS 0 60 GOTD130 700 ELT N N IFN gt 125G0T0200 215 FORI 1TON 220 LPRINT B POT 1 K 0 230 A POT 1FA BTHENK K 1 12 240 IFA lt gt BTKENK 0 250 BscA IFK lt 560T0230 270 OUTPUTA 35 15 2 PLOTIA 4 3 280 X l A OUTPUTA 35 15 0 NEXT a rete CSAVE X CLS 500 X 0 0SAVEX ae X 0 CSAVE 10 500 INPUT WHITE W 510 INPUT BLACK 6 515 INPUT CONTRAST E
213. rly The tape motor doesn t come on when I press L DIAGNOSIS Broken keylinc Ry The First thing to do is kad the Micro Video Biagnostic tepe into your computer When the menu appears press key to nm the keyboard test Perform the test by pressing each key on the keyboard When all keys havc been pressed any that arc inoperative will be evident Use this information and the keyline chart below to deter mine which of the kcylines are broken 3 10 1 12 13 14 15 NW AND N O As an example Ict s say thet keys X P H 8 nd don t function when you run the diagnostic test By looking al the chart you can see thal al these keys are controlled by keyline 6 This then is the line you will check for a break Open your unit by removing the 51x screws from the bonom of the case Separate the lop assembly from the borom by carefully lifting the top up and disconnecting the key linc aud power supply connectors Make sure your compiter is unplugged You will then necd to get msidc the mam clec tronics assembly casing Remove the four large screws in the top of the housing and the six smaller screws on the metal connector panel To move the connvrctor panel down through the hole in the top housing panel slide the housing panel slightly Forward Now lift the connector panel u about an inch and gently maneuver it so that the front left corner can be passed down into the hole Follow with the back left co
214. rmance on each hole is 54 It seems to me that may be the minimum pessible scoe Is 1 Tom Slaughter Milan M Dear Jam Frankly I dont knew 1 wouid think that the lowest pessible svere en 18 holes would de 18 However some of the holes ore comNex anda hole in one may be im possible Has anyone out there beat 34 Denr Miciv Video Sory guys this is net a subscription te RAM Pages ve got better things to do with 20 Did you knew that 20 is the price of a ears subscription to Compute magazine Hew can you charge the same price for a 20 page newsletter that only comes out 4 times a Although the Guide to ROM Sub reutines was welcome it fell shert in sev eral key arcas l beught this hoping to ind seme explanations of the Interact s i a se pu E aad atl ur computers Hey re ee E a characters pee REE cs PUloe l Sman ee ae ETTI E sighi T A Ran pee a ee I T bie cn ea i A fe ae i ee T ls a tt pl ie iA I i Ht emi n riley fa eae a a a ace oe eY o y fe 5 Le aa pF m When vou re done vos K x tape routines Butno nota word I had te first disassemble the meniter then Level II BASIC to find out what 1 needed to know If you turn to page 14 of the Guide you find a description of a routine called SNDPAS which is supposed to centrol the pass thiu ef tape input and sound output But it decsn t do it at all if you look ata disas
215. rnenas a BASIC program will automatically cun when you ptess RESEF then Re to vestart Load in a BASIC program you have handy then enter these POKEs from the keybeard to check ir out cies as possible We ve released a plethora of new software and aecessories rewritten the BASIC manual entizely to make it a solid training tool and reference docu ment and have developed hardware enhancemenws such as che RS232 port and the 32K expansion which nteract said counldn t be done We ve establish ed a full repair facility with a technical wizard who can fix anything Like In teract we re limited in our resources theres only so much eight people can accomplish We do have a much larger seeff devoted co markering and customer support chan dtd Ineetace so calls get returned letters get answered catalogs and newslerers mailed n a market as diverse as the Interact maket is we ate realistically never going to be Before You Go Poking Around remember to POKE 19213 25 eo be able co use PEEK ot POKE This will be understood and por shown a the counne given so if a program doesn t work kal co see that you did that im portant POKE Secondly if you ey to PEEK level Ul BASIC you ll find that there are limits on the locations rhat can be examined You can remove those limis with che following three POKE s acements POKE 30462 195 POKE 30463 25 POKE 30464 119 If you plan to do any PEEKing in Level Il ic s a g
216. rner of the connector panel then slide the whole connector panci through the hole and hf the top housing plate toward the back of the computer Youre now ready to find and repair the line break Look at the twisted grey cable that runs between the con nector panel md the main PC board The line break ts most likely to be on the underside of the connector panel Counting from left to tight locate line 6 or the line you have diagnosed as containing the break If it is broken carefully solder the line back onto the connector panel If you did not find a line break al that end of the cable fol low the grey cable down toils connec tion on the main PC board Then counting from night ta teft check the connection on line 6 and repair if needed If both connections are good the problem is not a line break but more likely to be a bad chip either IC3t or IC32 You can try replacing either or both of these chips or call the Micro Video Service Department to anange for the repair After repairing the line break or other problem reassemble the unit Always run the diagnostic test again to determine whether or not your surgery was successful a 32K CORNER On Converting TRS 80 Programs If you ve upgraded your computer lo 32K youll want to start exploring the capabilities al that extra RAM gives you Onc of the advantages of the additional memory is being able to use many of the programs published tn books and
217. ronment such 3 a haunted house castle jungle or cave in which there are a number of obstacles and ob ects you can t1S to over come them The program has a vocabu 4 PRODUCT n oo m a PEP Se a Er etl e ega peee ani ie E E ge a n Ei St me Li e sant e ee ee pee J E pa AN oe Da amai na a aa T ne a a e pr ATE em pap ai ra a ee eg catenin goog ss s a Tr pay aT K TE ar ear TE Ee ee gai F sn ee ee eae ne cnet ae ne ae eae Sh of ee te Pee et ee s m ppm minnn eee ia a E a a a aia a na ae alia fork Teka heen ey wud e i l a el l n a E m a Ta oe m a mrsa T N T is Dynamite Tired of yelling at your Interact How bout letting it yell at you With the addi tion of the Votrax Type N Talk T N T anew Widely publicized voice synthesizer your Interact now has the bower of speech True the voice ee sound more tike a robot than the age on Star Trek or HAL from 2001 but the speech is quite intelligible and easy to program The unit is a small sel contained box with its own power supply and amplifier It uses an 32 interface yep plugs right into the port on any so equipped Interact To make it talk you just type The unit talks in ASCH so you can use either ee COMMUNICATOR or LPRINT RoZ32 or 32K BASIC The unit seak F when you hit a carriage return and can hold up to 750 characters in it buffer Of course there s a
218. ros f it s net something you re interested in then don t gt ie Bot om line Software is hard work co produce It s just noe fair to ask for listings or routines co ptoduce copies With BASIC even more 30 Micosofr owns our BASIC and Mxso Video spent a loe of money for a license to sell it A published listng either free or for sale would be in violation of thart license Try to keep in mind that it costs Micro Video teal dollars to suppore the Interact markec lf they don t get a fair return on cheit efforts they won t be able to afford eo comwwe that support A loc of you have asked for more hard wate information in che newsleteer We will be eoveting hardware more but on a ielacively simple applications level I m mot a hardware experc nor does Micro Video have a large staff of electronic engineers The information we ll provide will be basic and useful to the average usec If you want so be a tinkerer then do so and tell us whac you te come up watt The Inmeerace Network Newsletter is a perfect forum for information exchange between users so use it that way A few of you have the impression that you must have more equipment to make your computer worthwhile Have you esken what you already have to its mits Miao Video is prodang new thar all the time In the Spring catalog they ve lissed four new BASIC gemes two new RS232 pregtams a new machine language game and the expansion to 32K RAM Many other things are being readied A
219. rprizes Manu Tronics slepped making Interacts at the end of 1981 At thnt time Micro Video bought a substantia pertion ef their remaining parte inventory and assumed wnrranty coverage for any units still under warranty NCE CHC This firm in associa tion with Newman Computer Exchange bought approximately two thirds of Interacts final inven tory Through mail erder promo tions NCECHC sold the computers at lire sale prices Most of the com puters were sold as is with the understanding that no further ser vice or support would be available and mos packages included all of the seftware available from Interact at that time NCE CHC referred their customers to Micro Video for post sales support repairs and addi tional software firms Interact Electronics Protecte Enterprizes This company served as the factory eutict for ManuTronics They distributed the medel R the original Interact software and software they obtained from outside sources including the Micro Video Monitor Other than Micro Video Protecto was the only firm to attempt customer support for the machine However when ManuTronics stopped producing Interacts Protecto began sellin other ty es of computers and turn over their customer lists to Micro Video Micro Video Although Micro Video purchased a quantity of com uters during Interact Mlectronics ast days the cumpany has never been heavily orient
220. s input from the keyboard make sure you check the keyboard frequently The same goes for joysticks In controller based games you must check for input from the controller almost continually for good respon siveness It s terribly Irustrating to know you reacted quickly enough to overcome an ubstacle in a game but still lose beeause the joystick wasn t checked quite often enough On the other side of the cotn you don t want your progyam to accept input so often that the slightest touch results in reaction and loss of control In gen eral the rule ss that the less frequently you check for input the slower paced the game will be Pacing is another important factor in game operation The desired pace will vary according to game type and may even vary within the game itself A car race game for example needs much fastcr visuals and reaction time than does a strategy game like Chess or Backgiummon You may wish to design your action games so that the pace steadily increases with the dura tion of play Random apcraton is also a require ment In a player Vs Computer game the computer s staitiag move and play should not be readily predictable Ina math drill or other educational pame you certainty would nol want to pre sent the same set of problems or mate rial each time the game ts started You can achieve this randomizing by interns illy using a 3andom seed to slar randon number generation Allow the
221. s also a smali prox imity switch hidden in the door When you move your hand near it the door opens But Don s favorite method is a beeper transmitter sys tem similar te a garage door opener which can override both the metal detector and switch And that s not all Don is installing a micrewave scanning system under neath the f berglass body that is acti vated if anyone teuches the car or even gets teo close When the system detects an unwelcome stranger a message like INTRUDER ALERT will blast repeatedly from a hidden car apenas This whole project is an ego trip Don candidly admits This car abso lutely has to be one of a kind because I ve devoted a good part of my life to it even though it s mostly a hobby Marine Powered Menus The computer incorporated in the back of the console runs around the clock on power it draws from two modified 105 amp marine batteries A custom PC board controls more than 30 specially built relays The one major problem haven t solved yet is what to do if I ever lose power in both bat mame teries Don says I don t wee want te have te reload tapes to be able to drive Besides monitoring the car s basic electrical func tions the Interact uses a simple BASIC program to display a series of menus which Don uses to control gear shifting and other oper ations when driving His drive menu fer example initial
222. s current format doesn t include advertising free or paid We re in the process of redeftn ing the fermat now and changes in upcoming issues may well include a user bulletin board The Editor Dear Micro Video About a year ago I purchased the Interact computer because it was the least expensive of all the computers I saw I had planned to get to know a little about computers and then move up to an Apple or Atari 86 but I ended up very pleasantly sur prised with all the new products coming out the very low prices and the newsletter I have a feeling I will he sticking with the Interact for a long time Paul Davis Levittewn New York Dear Micro Video I just received my first copy of your newsletter and I am very im pressed 1 like several other people purchased my Interact R in No vember last year only to find out in January that the Interact was no longer being manufactured and the company I purchased it from placed all their sofware on sale the next month I was wondering what I was oing to do with no support for my nteract when I came across your name and address in one of their club newsletters I wrote im mediately for your catalog only to find you had lots more software than they had carried not to mention the 32K memory expansion and the Exatron Stringy sponge for openers I am so HAPPY I m already trying to figure out the quickest way possi ble to gei the money tobuy them and the n
223. s i d ii Sy eaa E z p O alll ne x lt Dee 3 NGV 2 i id 7 5 aa 54 r 02 465 wi 53593 Oo lhe Putures and graphics m RAM Pages a60 w you enpyment os understeodmng of the newsletter or tte articles Lives C a0 Do you wish we would LJ Print more photos and graphics _ Print the same amount C Print less graphics and more words Please gae us tome specific feedback as to ihe ditucles you d dhe lo see in upeOming RAM Pages If yeure intrested in more haedwara informal en fer exampte what aspects of the hardware would you lind tetevant any other comments you leel would be useful to us ia considering your particular ds Optional Name n OOU Address City Staie Zip Phone Copyright 1983 Micro Video Curperaien AH rights reserved
224. s reloading tapes to make changes in your cade So far that s a lot of processing powcr in aniy 4K and vou havent even ined change the contents of an individual Jocation or two directly rather than editing vour source file and reas sembling it For those times when you want a close up detailed view of your program voull be glad You know Al The Monitor While not a Cfull Aledg ed monitor AL has the primary features voud want in such a program AL will display the con tents of memory or the registers far you on command He will let vou sub stitute values in metnory or set anv one of the eight registers to a specific value Hell even let you use a label as the register value And for your debugging pleasure AL will assem ble and rim your code with muitiple breakpoints and lct you continue execution after the break As stated carlier a programming language is hardest of all programs to debug So in leght of the Asseinb ex Editex snafu you might wel wonder how vou can be sure AL iz really im working order We can guarantee it because we ve used AL internally for some time now In Fact AL was the developer of several of our most popular action games in cluding Hot Rocks and Heads Up Pinball Now we re not saving AL will instantly male you a super pro grammer But with AT the Editor Assembler and Monitor at your side voul sure have a much easier time becoming one yy 3 Micro Video s Service
225. s several other func tions Fhe second parameter which you specify as a single two byte number is passed in the D and E regis ter pair This parameter although loaded as a single value is interpreted by the computer as eight two bit control values for sound registers A and B located at 2800H and 2800H respectively What happens next is fairly complex If you want to find out more about how the sound generation circuitry works examine the schematics in the Interact Service Manual page 6 lower left corner of diagram To use sounds in your machine language programs you ll first need to incorporate the SOUNDL routine into your code Here ts a listing of SOUNDL SOUNOL MVI A 40H DISABLE SOUND DURING CHANGES STA 2802H SONDB 2 XRA A RESET ONE SHOT CONTROL gt 50 STA 2601H MICROSEC BEFORE OUTPUT PUSH H LXI H SFOOH SELECT MIXER OUTPUT SMISOO MOV A C XARA M ANI 07H XARA M MOV MA STA 3000H MISCOUTREG LXI H 2003H SONDA 3 MOV AE CALL LATCH8 ATCH SELECTIONS 00 to 7 LXI H 2803H SOND8 3 MV AD CALL LATCH8 LARCH SELECTIONS 6 YO IS POP H RET LATCH8 MOV MA ADO A ADO A OCR L JP IATCHE RET New you can produce a variety of sounds simply by specifying the parameters for the C register and DE register pair then calling SOUNDL For example the following routine will produce a high pitche rapid beeping that you might use as a win sound ina game The first line places a value of 03H in the C register
226. says That s because when you add the extra 6K RAM it puts more of a load on the system When that hap pens a camponent that s weak to begin with can be pushed too far and to go bad It s not the upgrade itself thats so difficult to do it s every thing else that can go wrong ne of the most common problems is that with the extra load the 12 volt or 5 volt power supply gaes Before the upgrade even starts the machine ts tested thoroughly to Ed Sears make sure there are no apparent problems which could hinder the memory expunsion Then alter in stallation cach upgrade goes through extensive testing The com puter spends at least t2 hours on the burn in rack to induce any RAM failure or other problem that might result from heat build up nlv after it passes this test is the computer returned to its anxtous owner We just figure that customers wouldn t be happy ifthey did the up grade themselves and then some thing else went wrong that was not even their fault Tim says They are u lot better off knowing that whenthe machineleaveshereitisrun ning properly And ifthey get ithome and something is not working prop crly they can get a hold of us and send it back within 9 days and we ll f x 1t free That goes for repairs too The other major part of the de partment s work is repairing ailing machines n average about 35 units a month pass through the de partment Tim and Ed
227. se both programs to help organize and manage your financial sales inventory or other business information With DREAM and VideoCalc s lexible powerful formats your key data is there when you need it as close as your finger tips r gt Who s Who The Geneology of the Interact Computer Interact Electronics Manu Tronics NCE CHC Pretecte Enterprizes Micro Video _ No doubt you ve heard at least one of these names before A number of companies have played significant roles in the Interact computer s history and many of you have ex pressed confusion as to the inter relationships between the various organizations In lact some people think the companies are all part of the same entity This identity crisis causes dif ficulties all around For you because you have trouble getting the service and support vou need and for us de cause we end up taking the rap for other firms failures to perform We ve had orders for products we don t offer in our catalog angry let ters demanding refunds on items not purchased from us and complaints that we did not fill orders that turned out to have been placed with one of the other companies One cus tomer was furious because he d sent his computer in four times fer repair and it still didn t work our records which we keep in detail for each in dividual customer indicated that his cemputer had never been in Micro Video s repair shop
228. sembly of the routine you ling that the calling parameters aie wrong and the ivutine doesn t do anything fer the tape sounds Any explanations Man Wilson La Mesa CA Dear Mare Sorry you don t fee RAM Pages is worth the price Lf we hocl es large e sub scriber bose as Compute we woulda have to charge so much per tssue And dues Compute gwe vou discount coupons on softwere ancl other products fer your Interact In fect docs Compute ever even mention the faterect The reason you didil find information adver the lefe ruutines in the ROM Guide is that they are not controlled vie the ROM but rether through routines in RAM as you probably found out in yeur dises sembly Well publ ish tape read write information in a subseguent issue of this magazine o dont have un explenetion for the SNBPAS routine People forget that Micro Video didn t write the HOM Interact Eletronics did We merely identified the mutines existing there tn the Guide I pre sume Interact Electromes simply over continucd on page 18 i g a tetis Peh e AE rp oe Gained ai ta Ce eee z SOR abt mmm rhe are rf EE f Lh E cE ees B SeN iid tae J Pe ere 7 te ahs ad LEP Tp eM pee ni TW ete ot Si iia LSE 3 7 9 k wes es A k Ha oe et Nhe i op Ren itj h Tr a g i D BEE a i E RR aera NE AS Bt f 5 a te Poa i E pes m EEL ELD We LMP ELIE al mra he d e Tiri ns T ca i iafel ge i uE a ee a the Kg YL N
229. ses the computer s tape deck us an audio source for lecture material that is recorded on tape VVithin the recording are instructions lo the student lo access various screens the instructor has defined and stored These screens may contain blackboard material used to rein force the audio lecture material or they may be used as a means lo lest student retention of the concepts pre scnted Aulumalic scoring of carrect and incorrect answel s is built in CAPIT makes it possible for instruc tors to formal teaching programs without Knowing how to program The skeletal structure of CAPIT makes it exible cnough ta be used with a variety af course material And of course the misterial can be cus tomizcd to the students abihities and age groups Late Breaking News The Dream and VideoCale progvams are finally avail able Releasc was held off so that more new features could be added and the programs completely debugged Each program includes extensive 40 pages documentation which ts both cnlertaming and informative More about both these programs in next issue s Product Notes lat incredible Thanks Paul Can anvbody ont there top this ane rat NEW LOOK Notice anything new about your newslettcr Yes it has a new name and this is only one of the changes now occurring at Micro Video Normally Micro Video is relatively silent about future plans until everything as assured the best latd pnns of mice and men
230. side The memory cx pansion was difficult to design and is a TIGHT fi one reason tt must cur rently be factory instalied It just physically won t fit with the other port It s impossible for Micro Video to iry to design for any eventuality or other products that might be produced by other sources They do design ail their products to be compatible with each other including future hardware and software enhancements A good thing to keep in mind when considering additions to your compater P S Many peopie have pulied the other port from their units and installed the Micro Video port and expansion d d hike to get audio from my com pier ami pipe it directly into my stereo ls there o way f can do this A Yes there is a way but CAU TION only those with some hardware experience should try this If youre not sure DONT do it Look for jumper number J4 it s right next to the RF can in the back neht corner of the man electronics as sembly This is a direct audio take off Run a pround to any convenient ground point in the computer also Suggest you check the output level before deciding on an input to your stereo It is probably high enough that youli have to go in the AUX input You should also consider isolating the linc but ll leave that up to you Note Micro Video cannot accept any re sponsibility for this modification or damage to equipment resulting trom it so youre on your own The Troll
231. size in the TV dic plav Chester L Willans Dayton YA Dear Chester A complete listing of the POKE loce tions is more than quite an undertaking ne of our programmers actuaily sat and P KEd al the locations to find out what epula happen lt leok him weeks he re Ports Piss he found that POKES in many lecatiens simply bombed BASIC fercing him lo ibad will investigate the feast bility of making the notes he took availa le fo vou and other owners Interact Electronics promised a fof of things they didn t deliver before they went out of business in the winter of 1979 We ve made some of them avotlable such s the RS232 port fa nn upcoming iwsue ee fi publish haw to convert the R5232 to true dual pori ROM BASIC hoivcver is not likely to became a reality at this peint The cost of producing tt wouid be in excess of 12 000 so given our smalf market size the price lag would be high 1 doubt many owners wouid bv willing in pay the pri e we d have to chare Nou neat news on decreasing the cherecter size to report 1 dont know tf ne news is geod news or bad news inthis COSY Dear Micre Videe My youngster Chris is taking over the computer Orders will come from him in the future When you want to replace AL with another assembly sysiem program mine is available It is written areund the amp lbi assembler my edit program and your monitor lt takes about 8K in the 16K machine Stanley Hechman Monmou
232. sters non combat magte combat magic tems rank and zniscellaneous fea tures If you send us a note with your next order or a self addressed stumped envelope we l be glad to send you a copy Thanks Jonathan Pardon me Modem Tymshare is now selling recon ditioned modems for 39 95 complete with a 38 day warranty Acvording to Barbara Bridges of Badger CA Mine works great with the Micro Video RS232 port Your printer cable can be adapted by inserting a switch between ping 2 and 3 in the cable The modem is Tymshare model 00 300 baud transmission DDA compat ible RS232 tnterface full duplex ortginate only You can order through Tymshare loc 20705 Vai ley Green Drive Cupertino CA 95014 or call 1 800 228 2028 ext 558 Happy modeming Password Pique According to W J Moore of Pitts burg CA the Password Please program entered in the Better Mousetrap contest can be defeated easily with the LIST command He says If you go into BASIC s command words and change a letter or letters then LIST will give a syntax error In addition if an incor rect password is used en the program then line changed to 11 NEW will erase the program Now that s security Lost in Haste Robert Alpert of Camden N J sent in two programs tone for 8K Graphics BASIC and the other for 32K BASIC that will alleviate the problem of losing characters when typing quickly with the new
233. t 10 P KEI9474 80 POKE 473 0 FORA 204807020 510 READB POXEA B NEXT 2 CLS OUJPUT SELECT MODE 23 60 1 OUTPUT I OR 2 38 40 2 30 A INGTRS I IFA 1 THEN70 40 IFA3 2 THENCOLORO 0 7 7 GD1060 20 GOTO20 60 ee 20496102050 REAOBPOXEA S 70 A USR 0 80 DATA205 115 5 33 160 73 174 43 174 119 124 254 63 1 4 6 80 58 239 95 90 DATASO 0 24 58 240 5 50 0 16 195 3 80 1 0 80 205 246 7 CRISS CROSS Programmer Bob Fett Dearhom Heights MI 5 CLS COLORO 2 4 8 0 FORC t703 A 1 B B 1 FORY BI07 FORX 112 008TEPA I 20 FLOTX Y C NEXT A A 5 24EXT NEXT 50 B 0 FORC 1703 A 1 B B IFORY BTO 77 FORX ODN 2S TEPA PUOTX Y C NEX 60 A A 5 NEXT NEX B 7 FORC 1703 B B 1 A 1 FORY BIOISTEP 1 5 FORX OTOIIZSTEPA PLOTX YC REXIZASA 5 NEXT NEXT 90 8 77 FORC 1703 B B1 A 1 FORY BI0iSTEP 1 FORX l12T OSTEPA 3 P4 0TX Y C 95 WEXT AtA 5 NEXT NEXT 100 GOSUB150 COLORO 4 1 2 GOSLB150 CDLORO 2 4 1 GOSUB150 COLORO1 2 4 no 6030100 150 FORT 1TOI00 NEXT RETURIN SPIRAL Programmer Gave Oatley Georgetown OH 10 CLS R 1 20 C C R R 05 25 IFC gt 3THENC 30 T 1 05 A PLOTSO R C0S 1 35 R SIN TE C 45 Y1 1J0 SIN X 50 A A 1 IFA 7 12001060 55 GOI020 60 A INTC RNO D 6 1 B INIZRNO 1 6 1 D INT RNOX3 6 1 COLORA B 0 A B 0 70 GOTO6D THE DRAGON Programmer Peter Fox San Jose CA 10 CiS COLOR47 1 7 FORI I1T0S0 0L PUT E57 1 39 3 OUTPUT 57 1 43 3 20 DU TPUT t 52 1 45 3 NEXT
234. t f whal you wani and need irom yaur computer we d appreciate your letting US Waw your thonghts and ed as on RAM Pages and other aspects of Micro Video s suppect as well as seme intormaisen aboo l yeu and bew yeu use yeur compider Mow many latesact computers do you can How ag have you owned it them Where did you pel your computes s C tnteract Etestrowics LJ Micre Video LJ Local Beater C Protecto Eni eeprizes LJ Manutreslics LJ Used fram a frend parage sale ete What is the memoyy capaci of your machines 00 Yiu have an RS232 interfase CI ves Co it YES what type Have you had any pmblems with C yes C me I YES please descejhbe aerssstererrrrasenerrreennn nner eres mm Oo you own a printer LJ yes C NG sf YES what kind Do you own a modem LJ ves CL no k YES what other systems Go you access Is the Intesact the onty micro nmiputer you have or use Ll yes LJ no lf NO hat othess do you ewause Mm How many peeple regulary use your Inleratt Into what age proup st do the usess of your Intesact Fat z 3 7 years 26 35 years 51 65 years 8 12 years 36 5 years 65 In what prolession aad o educational kvel de ihe uses of your computer fail 3 years J8 25 yeals Has yeur computer ever wekan down C ves C ne H YES did you O Fir d yourselt C Have someone else tix it C sind i1 to Micro Video fer pair If you sent it to Miere Vides pease rate the servace jou pol S
235. t com puter is a luxury most Interact owners don t have It s got certain limitations for us too we ve only got one of them and only one prog rammer can use it at a time So our Lie de also use tools like BASIC Assemblex Editex and monitors to generate software Which tools we use depends on the type of program we re writing Likewise you ll find that the type of program you want to write and your own proficiency in program ming will determine what tools you use to do the job Use BASIC for ex ample for programs that do num ber crunching especially if you want Noating point capabilities Machine langiage has no inherent A ability to handle decimal portions of numeers and to perform mathemat ical functions at that level you ll have to write or acquire a floating pom subroutine library BASIC also as many built in arithmetic func tions such as INT RNB SQR SIN which let you easily compute values you need Youd have to write your wn machine code routines to use these Functions in machine language programs BASIC is a very good place to start if you re new to programming it s fairly easy to learn especially if you ve got a good manual to help you along like our Basically Speaking This manual was designed to take the mystery out of programming your Interact 1t begins with the as sumption that you ve never written a line of code before and takes you on a guided tour of BASIC acquainting you
236. t opera tion with an Interact is technically possible and we have seen them ad vertised at reasonable prices ny 9 If you ve done much BASIC pro gramming you ve undoubtedly ser orig with an array or two You might have used an array with a single dimension to organize a list of similar items like notes on a scale names or counts You may well have used a two dimensional array to rep resent coordinates of a grid in a game program The uses of arrays are many and varied and it is not our in tention to pursue a lengthy discus sion of the whys and hows of using them in this article Array concepts and handling are discussed in Basi cally Speaking at least in their sim pler forms When you get into handling higher dimensional arrays though the situation gets stickier Basicad Speaking doesn t cover multi di mensional arrays in much detail al though it does present a simple ex ample of using a three dimensional array for a 3 D Tic T8e Tbe game In that case the BASIC statement DIM A 3 3 3 creates storage space for the contents of three paralel grids each a 3x3 square Note that the above DIM statement actually builds a 4x4x4 array but the zeroth dimension was apparently ignored for simplicity of explanation in that example tn BASIC an array can have as many as five dimensions or sub scripts Of course the memory s n straints of the Interact often preclude the use of four or five distinct
237. tape metor contrel program frem eur Basic Examples Booklet Darvl s program as written uses 500 as the ceunter for each program to be stered on the tape He says this should accommodate any program written for the 16K Interact However he also mves the method to determine the piccise program length to allow denser packing or to increase the counter for longer programs 10 REM BYTES 0 235 390 FOR LEADER 100 COUNTER FOR EACH PROGRAM 20 CLS PRINT PRESS F FWO PRINT 30 PRINT PRESS ANY KEY PRINT 40 PRINT WHEN REAGY PRINT 50 AS INSTRS 4 CLS 60 PRINT WHICH PROGRAM PRINT 70 PRINTI FIRST PROGRAM NAME 8 PRINT 2 SECOND PROGRAM NAME 90 PRINTI THIRD PROGRAM NAME 100 PRINT 4 FOURTH PROGRAM NAME 110 REM ALLOW ROOM FOR MORE PROGRAMS 120 REM ALLOW 1500 AS COUNTER FOR EACH PROGRAM 200 INPUT WHICH NUMBER N 210 FORI 1TO N REAOD G 220 EFG 1 THEN PRINT NUMBER TOO HIGH RESTORE CLS GOTOBO 230 BATA 50 1550 3050 4550 1 240 NEXT 250 REM ALLOW ROOM FOR MORE PROGRAMS 350 REM MOTOR CONTROL 360 CLS POKE 19215 25 370 POKE 4096 87 380 FOR X 1TOG 390 NEXT X 400 COLOR 4 3 2 7 410 CLS PAINT PRESS REAO PRINT 420 PRINF PRESS ANY KEY PRINT 430 PRINT WHEN READY 440 AS NSTRS 1 450 CLOAD Jo use this program 1 CSAVE the locator tape at the beginning of your multi prom am tape 2 Load in the multi program tape 3 Run the locator program 1
238. tch It is hooked between one side of the tape motor and ground Terry says if you can t figure out which terminal of the tape motor to attach it to simply hit reset L to start the tape motor Then measure the terminal voltages with respect to ground The terminal with zero or near zero voltage is the one to aiiach the switch to SPEER i iim a aa TE TLE Hir E edebenibes aie pubis i E Pt peers te T oa Ff TREE a yee ns nai 7 L aga Terrie pune athe jai p peat ae eer 11a CARNEA Eprat eea trie EERTSE TTT epe ay rrr lie went pfeaenenvennainens A unr aH jigans iiai ek selene pene PP ite aden Saleen sn rel i i j ag Tak pecan et B mt a epee paca gh ham Ewi ee hd Ahapa peer elite tape ai testo Oy oa g be al l pana bt Rer ar an ERNE mans la ambert i Hei 1 aw ane ht spend emia Ey A eae E A qin oco ee qant ampalai sA i Deme o r i j miak i z ETE i i BET a pe ew Fabs i iA HME RERTERares tL paaied ranea 4 Lita aa enei ar aA ED resting ree Loe fs Larger Aa aes eamet bk ao eeeeenies Ee theerg thas HP ante Pip as energy ops Ae et HAE e m Sabaneta ant pearpiny aoe NN bt sprit baad C Je erre ETT rate EERE aman 7 Bade japane RR AA ore Emaan bape ee See TEA prI S dal kra voila vs adders if as R r ii ai F arr RENS Aaa ara mrar aF N 1 a E hs Hie dd peebbt 0 Magupi Saat thet LRE T oe A hirsini erT TT ates eTREPEL are Li 4 HH i TE STELT a
239. te result ooks pefectly normal reflecting the format controls embedded in your text fite did however have some trouble figuring out how to use the format ting codes I suspect though that my difficulties arose more from the sketchy documentation nee pro grammer s notes was given to test it with than frem any real deficiency in the program itself MV assures me the final instructions will be clear and more complete Once de ciphered use of the format codes i was able to produce justilied and non justified eepy center titles set tabs for columns of information poy margins to indent informa tion between paragraphs and moje STP also lets you set the baud rate and other LO parameters sequized for your particular printer If your prinicr has special capabilities such as come or expanded text you can also specify those formats for printing In general give STP a thumbs up If you liked the concept of Mic rotext but disliked storing text in BATA statements and tediously slow rint speed you ll lind this machine language word pruvessor a more than reasonable alternative While it s more complicated to use than Micro text the on screen cditing features make it ultimately more useful and well worth the challenge Coming Attractions Also in progress is Dreamland a real nightmare of an action strateg game from the developer of Mazes and Monsters In the upcoming catalog you ll also find Mega
240. ten something you believe is marketable by all means send it in QI3 Can I pet schematics for the RS 232 port und 32K memory expan sion Weve had numerous requests for these schematics Unfortunately our arrangements with our supplier Jo not permit us to release them Qid My computer is broken How do I po about sending t m fur repair First of all give us a call There may be some adjustment you can make yourself such as a tape head alignment nd you can avotd sending it in Ifit s ecally broken pack itup in its original carton if possible and send i to US at our street address Include your name address a phone number where you can be reached during the day and a brief description of the problem If you re pliuuung to pay by Visa or Mastercharege you can also include your cem number and expira tion date If you plan to pay by check money order or C O D we ll call you with the repair charges when your unit is fixed A 37 50 return shipping charge ts added to alt epar bills Q15 What f want to try to repair my computer myself Can I buy paris from you Yes We usually have on hand any part you might need to replace Call for pricing on the part you need Q16 Can I geta better keyboard for my Computer This une is se hard to program on Youll be happy to know that a protessional style keyboard ts def nitely in the works h will be a snap in add on you can install your self Because of long
241. teract s case Aside from the extta AC adaptor you ll notice no difference in its operac on until you type JFRE l2 FIRST CLASS SSS E SEF m Susi ALLET a o Copyright 198 Mim Video Conporton Af righi teseregd An Extra Word from Your Editor This expansion is really a major change in our liete Interac The added memory plus the enhanced BASIC will have its own column starting next issue The rest of the issue will mostly apply to all users but if you re really serious about Feedback Thanks guys I bought my Interact because of the price Admittedly I was a litile skeptical of the ad But 1 was dead wrong The In teract is a wonderful marvelous beautiful machine all che more so due to the low priee can t say enough good things about it We play the IV games and love them lve written a TV geme in BASIC and it wotks beautifully Ive written educarional programs fot my daughvet firs grade She does math drills and also spelling my programming suggest you give the ex pansion some thought For around 200 you can now have the power of a system costing much mote a great investment Call Micro Video for furcher details and to schedule an installation appointment P spc cecorded voice pronounces the spell ing words ovet Pm a cheraist by profession lve written complicated programs to help solve pro blems and prepare regos of analyses Apple TRS 80 PEf chey don h
242. th eee Sriartocs Falei toas re g dav party Dave began to speak ao shadowy se igure behind Sue ri ER Denim yi Aday ananta i Smartees has perhaps the Be pe por phic the plaza hardest working Interact in the o eate Aeel tha Inttrect ef lively pe Midwest maybe the entire uni verse he said Editor s Note This may be an exaggeration But if vou know of a harder working Interact costinacd on page 8 ot graphies feboved tt war ete je at ate tot nek 0 f nid Cathe Letter From the Editor PKS Trying to tell valued readers that their beloved publication is no longer geing to be free is a little like telling vour bevfriend lover wife husband Significant ether etc he has bad breath It might put a temperary damper en the relationship at first but in the long run you ll bath be bet Ler off fer it Joking aside after a great deal of deliberation by the Micro Videe staff we came to the decisien that from new en we have to eff er our pretty lit tle and getting bigger newsletter on a subscription basis enly We are not going to pretend that meney was net a major censideration it was But it was not the oniy one by any means And in the l ng run we believe yeu ll end up reacling a better mere timely newsletter The financial aspect ef this deci sien is I hepe fairly simple t under stand The last three issues have jumped from 12 to 16 to 20 pages Not enly dees this entail mo
243. th fet NJ Boor Stanley amp Chris First Ud like to tzetcome Chris to the Interact community As fur replacing AL I dori think we ll need te It s been very weli raved after Assembler works Just fine and ently eccupies 4K in GK sys fern Dear Micon Video You sell two kinds of games BASIC panes and machine language games know almost all abeut BASIC but don t know much abeut machine language Coutd you help me Josh Kirkpatrick Berkley PS Ages Dear Josh We dont really have any beaks or pr grams that are designed specifical 0 teach someone to program tn machine yE MEE oe a tt have tne n E E a a fly AE dard NAT a pp 2 oe w ti po eet REY DOArd ove ie a eee See a j 1 ey f i s 7 oe on ee ee a a bs a haf nlar RACK in ae eee a ro ra fae a a aa e Tal Eit i AE am lm hi Es bt T S a co J ara oe n ME YE HOLGA Ad i u age wat fk ae Be Deas kL LI x h the rue a Goo pa Pe a 7 a m F probably language Our Bombs Away program shows heu to cembine BASIC and machine language reutines ld suggest you gel that and the Montter or try as sembly ana programming with AL Vist your focal computer store te sec whut kinds uf beaks they have fer learning abeut assembly or machine language programming Dear Micio Video On Goofy Golf what is the low t pos sible scere The best Ive done on 18 holes is 76 though the total of my best per fo
244. th irs operation So if you get co New York visit your com puter s brother And don t worry about another blackout in Gotham that Interact has its own battery pack Editor s Nota For more informeven on Micro Vedeo S primary business Producing commercial edven ising soft ware lor major corporations see The CROWOSTOPPER in Creative Computing January 1381 One a pao Many BASIC games require the Joysticks The POT explanation in BASICALLY SPEAKING pg 10 61 states that che pot conrrol wil return a value of approximatety 3 ro 184 when plugged in and over 200 when disconnected We can use this information for a handy subroutine that checks tosee if the controllers are plugged in before the sume will begin We illustrate this in the following example In the exam pte we check only for che left controler You can of course modify it for the right controlier or both 10 REM GAME AOO ON 1000 A POT O IF AC 200THEN RETUR 1010 PRINT PLEASE PLUG IN CONTF 1020 A POTI O IF AX 200 GOTO1020 1030 PRINT TRANK YOU FOR T 1 7 SMALL How tight can you write Try your hand at Small Bytes The rules Simple Write a program in 3 lines or less Take your choice of Level 11 EDU BASIC or Micto soft 8K BASIC Send in your pxo 1 REM SCOTCH PLAID 10 COLORO 1 2 7 A 107 R 20 PLOTO 8 C 112 D PLOT T This column will appezr in each issue to answet your quest rons bott
245. the best far out graphics display is your choice of a 32K everyone s eyes are transfixed to the screen Then somecne yells out Oh Wow man look at that Farrrrrrr Out Mazes and Monsters comes to ife While exploring the microcomputer maze Micro Video stumbled acruss a cache of 30 Interacts These treasures had been hidden in a distributor s warehouse for many months When we discovered these jewels we hea snapped them up and c rted them back to the Micro Video Castle Now we hope to gain experience points by exchanging them for silver Theref ore we have a limited quan tity of new 16K RAM Interact com puters for sale A lot of have asked about the availability of more machines If you re one of them or rou know someone who steal your nteract iven half a chance here s our whiie they last Hidden Trea sure offer For only 379 00 439 00 with the new professional keyboard installed plus 7 50 shipping handling you get B 15K Interact Model with raised keycaps add 60 00 for professonal keybeard 2 Centreliers 3 RF Switchbox far TV Hook up he eee i expansion installed or an R5232 inter eSpa face and a professional keyboard and a package of incense 2 Three function Entertainment 4 Pr gramming Tools MicrovoR 8K BASIC e Basically sect Nae e BASIC Examples P Blank Data 5 Service Aida Tke Computer Doctor Service Manual klet ape Head Alignm
246. the computer But if vou prefer to stemp the compu ter you can Pack Wars is also one ef the few enuine two playcr games available or the Interact As its name suggests it s in the Packrat family Eatetts Dadotivus but it s muc more aggressive than its relatives ln the two player optien the maze con tains alternating squares of two col ors Your goal is to gobble all your color squares befere vour epponent eats his You can aiso blast your enemy lin my case usually my wife with photons which sends her flying to another part of the maze and scores points for you find it s the perfect way te get rid of my frustra tions at the end ofa long week When the computer s your adver sary the battle changes slightly As you eat yeur squares the computer doesn t have squares to devour you leave your scent for the computer to track The idea is toelude it until vou eat all your squares Again you can blast your pursuer but the computer is a sly tracker Youll need a strategy like teaving several trails 20 throw it off Through skill level selection you can control how fast the computer moves for an easy er hard game Clear five screens and youll win the war Ofcourse game reviews are highly subjective All you have to do is check around Micro Video to see that For example some MY staffers prefer Silver Dragon for its graphics and rapid action Others like Jumping Jack because it s more like a one on
247. the generation of machine code a simpler process With Editex you write the program drawing from a set of standard Intel instruc tion mnemonics Then you use As semblex toconvert the Editex source code into its hexadecimal equivalent values You can learn more about pro gramming your Interact at the machine language level with books like Spracklen s Z80 8 8 Assembly Languege Programming which we carry or other beoks available at your local computer store Our Guide to ROM Subroutines tells you what routines are resident in the Interact ROM and how to access them from your programs If youre learning ssecinblo language you may find the Dissassembler Plus useful With this program you can convert hexadecimal code back to its assembly language source instruc tions and produce a printed listing you can study to learn how various operations are performed by a pro gram And it can save you hours of time when you usc it as a tool for debugging your own machine language programs You can even disassemble the ROM or the Disax sembler Plus itself There s plenty more to say about each of these programming areas but space is limited here in RAM Pages If you want to know more about any of these programming aids or if you want recommendations about which will best meet your programming interests and skills give us a call AICRO ZY VIDEO Product Catalog _ Exatron Mass Storage Pack Mass storage with
248. the top back very far before you expose the main elec tronics housing There is a hole in the top of the casing approximately halfway across The sound tank coil MMM fy ie Sound Tank Hole is located directly beneath this hole see diagram Now take your hex tool and insert it into the hole seating it in the coil lug Raise the volume on yeur televi sion setso that the hum is clearly au dible Then adjust the alignment of the coil by turning the hex tool slowly left to right and back as you would do for a tape head alignment As you turn it you should notice the hum grow louder then softer You should also see a related distortion of the screen image as you do this Unlike a tape head alignment where the goal is the loudest signal possible te ad just the sound tank properly you will want the hum to be at its lowest level and the characters on the screen to be sharp and still After performing this adjustment you should experience a noticeable difference in the quality of sounds in games and other programs There are however occasions when a sound tank alignment will not cure these symptoms If you still experience the loud hum after aligning thecoil your computer may have problems caused by faulty circuitry in the RF or audio section Solutions to these more mayor problems can be found in The Computer Doctor repair guide And if you need additingal help call Micro Video to talk to m
249. tion techniques See asically Speaking If you really need more RAM I d recommend you upgrade lo 32K then add ROM BASIC later Finally I believe some one out there has FORTH any info for Robert The Editor Dear Micro Video We are really looking forward to playing the new adventure game We had so much fun with Troll Hole Adventure we really felt a bit let down when we figured it all out Once we got into letting our imagi nations expand we were on our way and all the laughs we had were worth the price and more The Dykstra Family Racine Wisconsin Dear Dy estras I m sure you ve received the Mys terious Mansion by now and hope sl beer enjoying it as much as I td The amp dtor Dear Micro Video What I don t like is high prices Why do you think we all bought Interacts instead of Apple HE or III s I am sure I will someday but I ll keep my Interact for playing games I do however appreciate your hard work at providing useful software that is compatible and gen erally flawless Your free Newsletter is great but does it allow free adver tising or program exchange Philip J Davenport Seattle Washington Dear Philip We don t tike high prices either Unfortunately our suppliers keep raising theirs Check our prices against comparable software for Ap pees or other computers to see how low oter prices really are As fer as free advertising and program ex change RAM Page
250. tive end of the 10 mid capacitor to pin 14 of the RF chip LM 1889 and the negative lead to greund You may use either the foil along the top edge of the RF section or the side of the RF can itself as a ground Now the grid board comes into play You ll have to build the transis tor circuitry circled at the top of the schematic using the parts def ned earlier Make your circuit design as compact as possible as the grid board wil be mounted inside the RF can When you ve completed the tran sistor board connect it to the mam PC board and mount it As shown on the schematic you ll make six con nections Solder the appropriate leads to pins 8 9 and 11 of the RF chip Remove the RF cable frem its origi nal position on the board and attach it to the output pad on your grid boaixi Complete he installation by L5 12V RF Cable Ground RF Connection lumper Wire aii R87 r a a l _ E F x a el Joard Mount Ground Connection C16 Jumper Wire connecting the other twe leads to the 12V regulator and giound Finally mount the board mside the RF can How and where you mount it is up to you and there is certainly more than one way to approach it Our method uses two pieces of stiff wire such as resistor leads Solder one wire between an empty hole on the grid board and the greund con nection shown in the photo Attach the other wire to the grid board then solder it to the lower side of the RF can Th
251. trinsic hardware prob lems and it looked as though the cost to the end user would be prohybitive They didn t give up on the idea though anda method of mating rela tively new product the Exatron Stringy Sponge to our computer has been developed This device will give us up to 60K of mass storage with ran dom access Some ume ago Exatron began man ufacturing a device they called the stringy floppy t was considered a low cost alternative t a disk drive The recording media was a wafer an endless loop microcasscttc rather than a floppy disk However this de vice required a controller in the com puter and it was therefore unusable with our Computer without a major hardwere change Mass storage for our computer seemed to be unrealistic Until the Stingy Sponge This de vice manufacrused by Exnaton com bines a stringy Woppy with a smart controller that can be drven trom an STHINGY oe FLOPPY gam RS232 port A resourceful owner Mel Guiles worked with Micro Video to develop the hardway and software ac cess to this device and ta da a new star is born The Suingy Sponge uses interchangeable micrccassettes wil ers that sell in the range of 33 5 de pending on the length They can hold up to 60K of data Access is at 9600 baud Thats almost 8 times faster than the cassette drive The controller is buit into the Exatron equipment and the dtiver is in a PROM that fits into vour Interact weh no m
252. tter Mousetrap Centest This issue we were inundated with entries In retrospect we probably should have had more rules since this nearly turned out to be an anything goes competition We received a refreshing assortment of entries and we re gratified that so many of yeu toek the time out from your busy lives to submit entries Our original intention was to print ail submitted entries but due to the heavy volume we were forced to eliminate a number of them Some we discovered just didn t work as claimed and were disqualified Others were submitted without sufficient information or in such great detail that condensing the idea was next te impossible The Winner We ve evaluated al the entries and our judges have reached a decision They thought the Best Better Moustrap came frem Dave Schwab of Ann Arbor no there s no home field ecvaniere Dave has added a photo digitizer to his system and the results are pretty impressive His entry is this issue follow in no particular order printed below The rest of the entries we could SaNeEZe h pita A Little Light Reading Dave Schwab s photo digitizer eproduced ti the er graphic accompanying this article Using the suggestion etailed in RAM Poges Vol 1 No 2 p 11 he N ht a Radio Shack photoresistor 276 116 and connected it joystick port He used part of the bate of a ball point pen to house the light cell and attached the whole assembly to the head of his DEC w
253. ty Interact Plot continued fren page i please let us know We d love to prove him wrong Smartee s really one upped the competition when they chose Inter act for their erder display system Dave continued Rather than a dull black and white numeric display that merely announced orders ready we worked with Smartee s to design continuously running software that uses the Interact s color and anima tion capabilities You ll see a display that s fun to watch as well as infor mative It announces orders ready for pick up welcomes special groups sends birthday prectings and adver tises upcoming events or special deals He told us that the Interact with the aid of RF splitters and amplifiers broadcasts its messages on six color TV s mounted on the walls throughout the restaurant After we ordered a couple of staf fers immediately wanted to gravi tate toward the game room but Dave herded most of us inte the din ing area His plan was working smoothly so he thought While we unwound from the trip and waited for our pizzas he asked us to watch the monitor It didn t take long for 5 Also there are certain occasions when the Post Office is not required to deliver bulk mail at all For ex ample they will not forward it to a new address iplease tell us if you move The same of course goes if they can t read the address maybe the labet fell off or the address ts incomplete i c no a
254. u were about to set Wouldnt you like to be able to stop the game action at any time then resume play from where you left off Well it zs possible You can make this simple modifiication to your computer for about 1 60 and under an hour ofyour time You will need a utility knife e a two way switch and mounting hardware 3 one fvot lengths of 22 stranded for lighter shielded wire a soldering iron and solder Many lypee sin avainobte and can be used We used a Radio Shack switch 14275406 prised ut only VEU n normal Interact operation Pin 13 tHold on the 8080A micropro cessor is grounded so the precessor uns continuously Operation canbe haited by pulling the signal on Pin 13 high to 5V Therefore youcan add pause control to your machine by tying Pin 13 te a simple switch ne side of the switch will pull Hold to 5V the other will ground it By changing the switch position you can start and stop the processor as you like with no ill effects on pro gram operation First you ll need to mount the switch A logical place is the left side of the ventilation area on the upper plastic housing Use a stiff backed utility knife to cut a hole to fit your switch and mount the switch in it Next open up your unit and re move the 8080 chip from its socket Corefuliv bend Pin 13 up so that when the chip is replaced on the socket Pin 13 does not make con tact Solder a wire onto the end of
255. uncaveled earning the language and logic thae will make your computer do what you want is an exciting and challenging prospect Once you ve masteted usr ng loops anays functions and orhet programming techniques youll probably be ready to tackle the PEEK AND POKE UNMASKED more advanced aspects PEEK amd POKE are two of BASIC s most powerful functions but they have not been widely used They border on the unseen world of MACHINE LAN GUAGE Only wieches and warlocks have the power to tame these snange be ings At least that s what ncerace Elec tronics wanted us co believe PEEK to take a look That s exactly what PEEK is for It lees you find out what value is gtored in any given memory location If you PEEK an address BASIC will return the consents of that location as a decimal value If you re working with machine language youll find that mnemonics and ASCII values ate generally Furnished in hex idecima so youll have to convere chem to decimal for use with BASIC An easy way co do this is to loek it up BASTICAL LY SPEAKING has a wable for this purt pose page i 3 Ready Then let s wy an example With Level Il or 8K BASIC leaded into your eomputer type PEEK 25951 Gor a syn tax error huh That s because PEEK is a function not a command and you must PRINT che value of a funceion Try typing IPEEK 25951 Now you gora value of 79 right Now PEEK Z5952 The value s ored there is 1 7 These locations
256. ure probably having some trouble deciding which ones you want Se well examine a few of them in more detail than is possible in the catalog to make your decision a little easier for perhaps harder Heading the list of exciting new sofiware is Mazes and Monsters a complicated and challenging Dungeons and Dragons style game Afler choesing your race anda set of characteristics that determine your fighting abilities and magical pow ers youre off on an adventure un like any you ve ever had before As you wander through the dungeon which is a set of eight 16x 16 grid mazes three dimensional graphics let you see what s around you Your quest is to reach the eighth and low est level of the dungeon where a vi cious monster guards the Sacred Orb You must wrest it from the monster and return it to the Castle to win Danger lurks round many corners 15 different types of monsters will try to stop you from reaching your goal Mazes and Monsters differs from traditional adventure games in two significant ways First it is graphic rather than word oriented Also there is no single solution to the game A new maze layout is gener ated whenever the game is loaded or restarted with RESET R And bce cause tt can take days or weeks to finish a single game the program has a built in save game feature This one is a bargain at twice the price since more than 65 000 dif ferent games are possible ve seen all ages get
257. uses chunnel 3 for its output and that channel ts used for television st in my area Can I change the Intcract s output Yes it is possible to modify the R F output of vour Interact Contact Micro Video for infor marion on chis modification How can I get a sideways moving message effect like the T V news flash bullerins A There are several apprcacsies to this One way would be ro out pur the words erase them then output them again a few pixels co the side Another way is to POKE location 24888 with 1 Now each PRINTstarement will cause the screen to scroll side ways To return to normal scrol ling POKE 24888 32 See the new BASIC manual pp 10 57 and 58 for more POKEs 1 REM POKE SIDEWAYS SCROLL FOR LEVEL tt BASIC AND GRAPHICS BASIC 10 PQKE19215 26 CLS 11 REM LINE 10 NOT NECESSARY FOR GRAPHICS BASIC 20 POKE24888 01 POKE24864 01 30 OUTPUT MICRO VIDEO 0 35 1 40 FORT 1T0200 PRINT TONE60 60 NEXT 60 POKE24888 32 POKE24864 05 The following simple progam 20 FOR X 1TO3O000 was developed by a 12 year old D 30 SOUND3 X 40 NEXT Nor to be outdone too came up with a program that makes useless sounds The gauntler is chroun down sec if you can one up my sick bird 10 FORX 1T0O1000 20 SOUNDO 24844 SOUND3 264 30 NEXT Cut along dotted line On The Inside SOFTWARE DEVELOPMENT The software available for the Interact has grawn tremendously in the last year Since
258. vel Plot Chuck Yount of Granite Falls NC could qualifv for an honorary lron Man award He sent us a short three dimensional function plotter I wrote for Level il BASIC His short program is about 150 lines long too leng te include here but it plots as three dimensionally as the Interuct s graphics resolution will allow Hint stand back and squint He uses the DEF functien to change the calculations f the image to be displayed If yeu d like a copy ef his program aad us a S AS E er ask for ene with your subscription to RAM Pages or next order continued or pain 2U This is a contest in nostalgia Imagine that you and your Interact have been put in a time machine and for some un known reason you wind up a party in Haight Ashbury sometime in the 1960 s Jimi Hendrix blasting in the back ground Strange smells in the room Then an idea occurs to you I bet know what these space cadets would like you say to yourself You hook up your Interact to a nearby TV tum it on and run a program Suddenly What would you have put on the screen to elicit that response That s what this contest is all about We want you to write a graphics program in BASIC that will make our staff say Oh Wow man Farrnt Out We ll limit you to LO lines total for yeur special eff ects Send your entry on cassette tape not just a program listing marked with your name and FAR OUT GRAPHICS The prize for
259. velocity of the tocket then FOR ADVANCED PROGRAMMERS ONLY Pick Your USR As your programming skills progresses youll find the USR command increasing ly useful The ability to blend BASIC and your ovn machine language routines aliows for moce eomplete progJam con col as wal as faster execution The one major drawback co shis cogwaand has heen the inability to cal move chan one USR routine without a bot of fancy foot work Wich the following short piece of code y u can now specify USR wich a teal argument ie USR US 1 e0c By setting up a jump rable of two byte d SP dresses you can use this rotine to get and evaluate the urgumente then jump to che assigned routine My thanks to Harry Holloway fer this idea 10 CALL 6AB This routine in BASIC gets the argument and puts it in DE Saves BASIC s pointer on the stack LXIJIABLE Points eo the address of PUSHH ehe jump table DADD DADO Kicks ie up to the proper address MOVEM XH MOVDM Gets the address for jump XCHG PCHL Executes ehe assigned tTouQne Don t fosget char we stored BASIC poiner on the stack Ac the eompkton of your routine POPHR For more infor mation on USR see BASICALLY EAKING and the Micro Video MONITOR Guide Examples of the types of things you can accomplish with USR ate shown in the BOMBS AWA YI Pro gramming J utotial a ES IN BASIC fires At that porn the movement of the rocket is ouc of che
260. visible That takes care of covering the trail but the motion problem re mains The image still leaps from one position on the screen tothe next Smooth Moves To achieve smooth motion you need to use a routine that will let you move the image one pixel at a time Our routine to do this is called PIX PIC PIXPIC has the ere gt being slower than BYTPIC for ting the images to the screen an Me code is more complex It has some dis tinct advantages though that make it ultimately better suited for graphic motion The primary advantage of PIXPIC ever BYTPIC is that it lets you out put a picture at any given X Y screen location therefere you re not restricted to moving the image a full byte at atime Another advantage is that you store the size parameters in the picture table itself and PIXPIC retrieves them This means you don t have to passthose values to the B and C registers before calling the routine each time Graphic development is easier with PIXPIC too because you don t have to reverse the pixels in the table and your pictures can be designed in any width not Just increments of four pixels Since we have to modify the face picture table for use with PIXPIC anyway let s kill two proverbial birds and change it so that the pic ture can move in any of four direc tions left right up or down without leaving a tr ail uu AL Ha Ui The black border around the pic ture changes its
261. way here s how it s done Changing your Interact to video output is not a decision to be made lightly Te do 80 requires that various components in the RF section be re moved and others rerouted Once you have modifted your computer for video out returning it to standard RF operation is not a simple matter al though it can be done We have successfully implemented this modtlication on a number of Interacts and to the best of our knowledge t will work on any n teract computer It is however a complex procedure and we do not recommend you try it unless you have a background in electronics FFA erf Bii t Ae EFK was rT ca cy at LS ii eat eT a roe oa ft Mie 8 e Fits oie fre ee fe L iZe dl Fe S r the Micro Video makes no specific war ranty of the operation of this modi fication on any particular Interact nor will we assume any liability or responsibility for damage resulting from your own attempt to perform this conversion You will need several tools and one each of the following parts for the video out mod Parts Reeisters 820ehm Kohm S20hm 7Sohm Diode IN SI4 Capactors I0 microfared electiolstic L90 miciofored electralytic Trans wter 2NS9O4 ther Smoll grid board e g Radio Shack 276 158 Apprex 12 length 24 gauge Wid Ht cable yptional for audio honk up Tools Seldering Iren ond Solder Needlenese Pliers Phillips Screwdriver Xacto Knife
262. we ve been but youre probably more interested in where were going from here Well Folks we ve mote surprises in store for vou Tired of struggling to program on that blankety blank keyboard A real professional kevboard is on the wav with deliveries scheduled to begin in early November isee article and photos oti page J fa more infor mattoni And work is also in pro gress to solve our computer s other major drawback If our design works ax planned your literact may be able to have more than one graphics mode and smal ke characters Games vour hag Mure of thoxe are under development nnd several new ones have just been released including 3 three dimensional D amp N style ad venture Stay tuned In closing one final reflection I look at how versatile our dead computcr has become and wheire we re planning to take it and think itstruly remarkable You the own ers deserve a lot of credit for hang ing in there Your interest in and enthusiasm for the Interact has kept us motivated le support it Together weve brought the tnachine back to life A hearty thanks to all of vou We could never have done it without vou Keep up the good work Sincerely Sue denim Editor Program Notes a ome eo ome Ss come om mm em Sem coe Ee om ee co ee o n a a n n Programs programs everywhere By now you ve all received our summer catalog and the recent fall preduct update Both are chock full of new games and yo
263. will produce audible sounds So if you don t have success with one set of parameters don t assume the veutine is flawed just try some different values Oh yes There s one other short routine you might need This one turns the sound OFF MVI C 07H LXI 0 L000H CALL SOUNDL RET Me Symptom My tapes won t load Diagnosis This symptom can result from a number of problems e Defective tape Tape head out of alignment e Bad ground causing motor noise e Bad mechanical connection In drive or frozen motor Failure in audio circuitry Always try the simplest solu e tions first I ve found So the first thing to do is check and see if just one or a number of your tapes won t load properly If the rest of your tapes load a pk without preblems then the one tape is probably defec tive The Micro Video tape warranty covers replacement tn full for 9 days alter purchase Because we know that tapes can wear out or become damaged after the warranty expires we have liberal pest warranty eover age as well You can exchange any defective tape regardless where you purchased it for a new copy of the program at a 50 diseount ow the fun part If many of your tapes fail to load the problem is in your computer hardware Again try the easy solution first check that your tape head is aligned to maximum aignal strength Insert the Alignment cassette into the tape drive and press the RESET bution Press
264. with your RS232 port Atthough our RS232 board does havea dual port only one of the ports has handshaking capabilitics at this time We will soon be releasing a modification to the RS23 board that will give the second port himdshaking so you l be able to drive two devices simultiuteously Additional software control will be required You ll first sec the option implemented with re spect to the Exatron Stringy Sponge and by fall we hope to have a Com municator Plus program that will let you dump to your printer off a mainframe system For an interim solution see this issuc s Hardware Hints Qi Mast I have an RS232 iter face to upgrade my rompiucr to 32K Nope The two expansions while completely compatible do not require one another With both upgrades in stalled a small driver board is needed and is incjuded in the price of the 32K RS232 cxpimsion QIZ Fe writtena program I thinkis pretty good Is Micro Video in terested Fluw do 1 make sure you don t just steal ie We re always happy to evaluate user written programs for our catalog Our policy is never to duplicate or distribuic saftwure that 5 sent to us for review so you neednt worry about theft If we re interested in the program well contact you by phone if possible or by Icticr If we re not we ll return the tape to you with our comments We have made arrange menis wtth programming cathusias ts sm the past so if you ve writ
265. xperienced both can tell you they re radically dif ferent environments Not only js the technology very different but che market is as well Timesharing is by ise very n tute businegs oriented Sales are made to corporations rather than to in 6 dividual consumers like you and 1 The very firs problem Interact encountered I belteve was a lack of understandi their market how te penetrate it chen supper it Then chere was the matwer of the evolucion of the Inte act hardw re itself Dad you know chat the original interact prototype had no keyboard it was designed to be a low cest 4K game machine with no dixect rogramming access it so happens that Micro Video acquired the original prototype machine We thought you d be interested in seeing your computer in its early stages so we ve included a photo The dramatic changes that occurred during develop ment ate obvious The development process was long almost 2 years and involved and slowly the Interact as its exisse today emerged It was a cosdy venture by the time the computer was brought to market in 1978 ics backers had inv ted in exeess view a E i J z ye u L ae Ai a e The Interact Model i serial number OOO of a milion dollas in development alone The Interact had grown from a game machine that was to be com petitive with the Bally and Ac ri game computers to a fully ptograromable micro for which the main competition from a cost and ca
266. y electric ay pewter Compared to the pe ce of other letter quality printers this isa bargain you should consider strongly if super ver print quality is one of your requirements Microline s Oi Data We have and use an Okij Data printer made by Micreline and are quite happy with t The printer is widely available from dealers who handle RS232 printers and can be mail ordered for under 500 It is also a dot matrix printer and its only dis advantage is that it is a bit noisier than other printers in the same gen eral price range Comprint We mention this perni only be cause it was originally introduced as the printer for the Interact by inter act Electronics and we did carry itat one time Some Interact ownels may still havethem The Comprint uses a metallic paper which cannot easily e annotated and is now nearly impos sible to order It operates by burning the characters off the metallic paper and is painfully noisy We have no re cent information about the Compnint but the last flyer advertised it at about 650 00 For the price many other printers would be a better buy Other Options There are other interesting printer options available to you One of the most exciting is the typewriter turned lineprinter This ts an electric typewriter containing a board that allows it to be used as a printer Of course this gives you letter quality every time We have no direct experi ence with these devices bu
267. y of the failure of a sm Il busin s Mary asked me to guest author chis article because as a former employee of Inserace Electronics I really was on the inside When Interact folded 1 was still a relative newcomer to che scene so was in the inter ting position of being an in volved parey bue not 0 involved that couldn t be an objective observer I d been made aware of Interact s shaky statis before I joined che eompany therefere was particularly tuned into recognizing problems as they atose With that in mind il cell you Interact s story as know it Please bear in miad that I don t know the whole story 1 doubt thae anyone even the former president does the problems were long term and complex rl begin with a licetle his coty Interact Electronics was born ia 1976 the brainchild of Ken Lochnez Ironically Ineerace was then located in the very same office space that Micro Video now occupies Ken s history was impressive Hed been one of the original designer developers of BASIC back in his Dartmouth College days He heer tounded a high growth timesharing com pany in Ann Arharcalled Cyphemeties which was subsequently acquired by Aromatic Data Processing Ken had been se suceessful in his previous ven tures chat there was no ceason to believe Interact wouldn t be equally successful So what happened To begin with Ken came into the micro world frotn the timesharing in dustry As anyone who s e
268. y positive feedback it s probably worth send ing in for our response In general we re far more in tercsted in machine language pro grams which almost always meet our software criteria better than BASIC progi ams which can t com pare in graphics speed and overall sophistication A BASIC progran must be of exceptional quality to be seriously considered for our catalog As you design a program with the intent of sclling it to Micro Video strive for consistency with our other software For example if the game corned on poge 5 Meet the Programmers l music for the University of Michigan Marching Band Go Blue In other spare moments John does freelance musical composition collects coins and is an amateur film critic and would be film maker Tom Matulevich our other pro grammer knows the Interact like the back of his hand He worked in the repair area at Interact lec tronics and has also done service work for Micro Video although he now progranis almost exclusively Although proficient in BASIC Tom does most of his programming in hexadecimal with a monitor Tom learned machine language by POKEing BASIC repeatedly to see what would happen He reports that this was often fatal to the interpreter and claims to hold the record for crashing BASIC a some what dubious honor Tom s newest creation for the Interact is the spec tacular Wing It action game Unfor tunately he doesn t have too muc
269. you know but on this one occasion Til take you on the inside Micro Video has increased their commitment lo our computer its users and their needs Many new sofilware ties are currently being evaluated an l prepared for the next catalog so there will be no shortage of new materials in the coming months In fact you cin expect to see at least Interact Gets Dennis Hermes of Houston TX alerted us to an article that appeared In Comparer worki Ohacch 29 1932 On the front page of that issue in the lower right corner i a photo of a men and his compuler The man is Doa Povejsil Vice President of Corpoiate Planning of Westinghouse Electric Corp The computer is a 32K Interact Althaugh Cit deigned to identify the compuler in usce anyone who s famil iar with our hule machine would rec a W new programs by Christmas They ve also increased their staff to better serve your needs Good secviice made even beller Many new hardware enhancements are also in the works The Stringy Sponge is the newest to date bul an add on piolesssonal siyle keyboard is unger development and will be avail able later this year Probably the biggest news is that if all cocs as planned Micro Video will be manufacturing our little computer again by the end of the year Again under ii new mime bul with the same high quahty safiwvare and support ser vices Watch us prow PV the Business ognize those large characters You m y
270. your ideas a ld MICRO 305 North First St P O Box 7357 Ann Arbor Mi 48107 313 996 0626 fj VIDEO Bulk Rote U S Pustage PAID Permit No 250 Aun Arbor M pt z F al ce fy fy a ai 5 1 5 EX 4 gt Cepvrieln O82 Miers Video Corporation All rights reserved Wake Up Call You knew that not all daysin yeur life start out alike Sometimes you wake up happy and other days you may unexphcably awaken in a bad mood But did you know that this can happen with your computer too It s true When you wake up your Interact with the ON switch some times it gets upon the wrong sideof the bed On those occasions your Interact doesn t relate well to your TV set and the quality of the scireen display suffers Perhaps you haven tnoticed these mood swings in your computer All Interacts have them but dependin en the sensitivity ef yeur TV set an how its celor and tint controls are adjusted these changes in yeur computer s temperment may be slight and virtually impossible to de tect visually However once yeu re aware of this petential problem the difference between your cemputer s good and bad moods can be very apparent To experience yeur computer s moed swings firsthand perform the following test First adjust the color control on yeur TV so that the background is a rich blue Then set the tint contre to the appreximate centeir of its range To find the r
271. ystick and expose the feur emall contact switches silver plates that correspond to the joy slick s movement Press cach contact with your finger If there s no spring to it then it needs te be replaced By the strangest coincidence vou can Hnd more of these plates in side the ekl keyboard dust remove the back separate the keys from the board and there they are Use the salderin iron to melt and remove the old joysirck contact Then sol der in a springy one from the keyboard ZapppPppppppp Chavles Cardwell of Kingston TN submitted 2 pro gram that while not particularly uscful is a flashy dem onstvation of some string manipulations that are pessible using BASIC We enjeyed watching it and hope you will too What Sollews is a shghtly condensed version of his pregram 20 CLS PRINT 24 FORN 17 012 25 J 17 30 FORI 1TOJPRINT Z NEXT 40 FORI 1T0J 1 PRINTCHRS 8 NEXT 50 FORI 1T0J 1 PRINT A NEXT 6 FORI 1T0J 2 PRINTCHRS 8 N EXT 70 FORI 1TOJ 2 PRINT P NEXT 80 FORI 1TOJ 3 PRINTCHRS 8 NEXT 930 FORI 1TOJ 3 PRINT EXT 100 FORI 1TOJ 4 PRINTCHRS S NEXT 110 J J 4 120 IFU 1GOT 30 130 NEXT 140 FORI 1T0204 PRINTCHRS 8 NEXT 150 GOTO20 ZAP PRINT EE LAATS continui un page id 13 2ackin n Trackin Dary Biscr of Warminster PA wrote a fast fast forward locator program that allows him to store several programs on the sume tape und find cach ene easily Itsa modification of the

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