THE PAPER FOR OWNERSPAPER OF THE COMMODORE PET'"PET'" PERSONALrcribuNAL COMPUTCOMPUTERER

VOLUME II.il. ISSUEISSUE 1 An ARESCO PublicationPublication February, 11979-979 $2.00

THE PET IN THE CLASSROOM WHAT REALLY by John Fultz, Lincoln School MAKES YOUR PET TICK? by Gary A. Maier The PET arrived arrived inin JanuaryJanuary —— aboutabout oneone monthmonth after the order waswas placed, and about two months soonersooner than expected. With the third periodperiod mathmath classclass (and I'm sure manymany of you are reaching the point where youyou the principal) lookinglooking on,on, thethe cartoncarton waswas openedopened —— and feel very confident workingworking withwith the BASIC interpreter, interpreter. out came a dream come true. If so,so, youyou areare probablyprobably asking yourself these twotwo questions: The PET was placed on a table, and the principal ordered, "Well,"Weil, make itit do something!" TheThe PETPET did do How can I make sections of my program run hundreds something that day — butbut notnot exactly whatwhat II hadhad of times faster? expected. The keyboard had a small but meaningful What really makes mymy PETPET tick? problem — theythey keys didn'tdidn't work. A quick call toto Commodore resultedresulted in opening up the new machine itIt wouldwould bebe impossibleimpossible toto presentpresent aa coursecourse onon machinemachine and jiggling around the connectors until the keyboard language programmingprogramming in one article, but maybemaybe II cancan worked just right. interest youyou enoughenough to convince youyou toto dig up more information on your own. In orderorder to makemake this articlearticle Things werewere goinggoing quitequite wellwell now,now, andand forfor thethe next six appeal toto a larger audience, II will start out withwith somesome minutes, all thoughts of problems were gone. Then thethe fundamental ideas, andand graduallygradually getget moremore technical:technical: screen went blank. After•someAfter some checking, it waswas finishing with aa discussiondiscussion of multiple precisionprecision discovered that something waswas overheated and caused arithmetic. the video output toto quitquit working. working. The The PET PET was returned to Commodore forfor repair,repair, and thethe problems werewere allall THE 6502 6502 solved, and the PETPET isis nownow in use by a hundred and The "brain" ofof youryour PETPET isis thethe MOS MOS TechnologyTechnology 6502 eighty 7th and 8th gradegrade students in their mathmath classes.classes. microprocessor. ItIt is an 8-bit processor,processor, which means that it cancan only process 88 bitsbits (binary(binary digits)digits) atat aa time.time. A computer can be used inin thethe classroom forfor manymany (Eight bits isis alsoalso commonly referred to asas one byte." things: teachingteaching studentsstudents how to programprogram andand operate a computer, assisting in instruction inin aa specificspecific The 6502 has sixsix internalinternal registers which are used for subject, and classroom management, for examples.examples. TheThe various purposes whilewhile youryour programprogram isis running:running: PET isis usedused inin ourour mathmath classes toto introduce the The Accumulator is the register used toto store data anon students to computing andand to provideprovide computercomputer aidedaided which operations will be performed. It cancan alsoalso bebe usedused instruction (CAI)(CAI) forfor allall students.students. TheThe newnew PETPET •• for temporary storagestorage and for moving data from oneone TUTORIAL Tapes Tapes will will bebe usedused asas CAICM toto teach the location to another.another. ItIt isis usedused byby thethe microprocessor microprocessor students programming in the near future. (the 6502)6502) toto storestore thethe results of most operations. The one PET has has grown grown to to two, two, withwith aa 20202020 printerprinter on The X andand YY Index Index RegistersRegisters are counters. often used order (and scheduled for delivery in December or to control programprogram loops.loops. TheThe 6502 has instructions January). We have plans for memory expansion and which willwiii increment (add(add to)to andand decrementdecrement (subtract perhaps an optical scanner. The PET isis aa partpart of each from) thethe valuesvalues storedstored inin thethe XX andand YY indexindex registers,registers, student's math class. and thethe students areare rotatedrotated so and those values can bebe comparedcompared directlydirectly toto values inin that eacheach of them has aboutabout 3030 minutesminutes ofof timetime withwith memory. TheThe registers areare usedused as indexes for the PETPET everyevery threethree weeks. The CAI programs that areare addressing. makingmaking it easy to handle data arrays. They used with the PETPET areare relatedrelated toto the student's actual are also used inin two powerful modes of indirect classroom activity. SomeSome ofof thethe advancedadvanced classesclasses areare addressing (or(or "computed""computed" or ''calculated"'calculated" addressing). introduced toto BASICBASIC programming andand havehave assignments to write programs. The Program Counter is the only two-bytetwo-byte (16 bit) register in the 6502. It alwaysalways points to the addressaddress In general,general, thethe responseresponse toto thethe PETPET has been great.great. which contains thethe next operation to be performed, or Often parents, administrators, teachers,teachers, and board the data for the instructioninstruction whichwhich waswas encountered inin members visit thethe classroomclassroom toto seesee thethe PETPET in the preceding address. operation or watchwatch demonstrationsdemonstrations ofof thethe PET. PET. The computer has been used for other thingsthings —— a program The Stack Pointer (and the stack concept) can be has been developed to schedule students into classes,classes, easily explained byby aa simplesimple analogy:analogy: a deck of playing labels & package $.50$.50 EDITORIAL postage $.50 (more if thethe programprogram includesincludes by Terry L. Laudereau written documentation, less ifif itit doesn't — this is average) Well, here it is — IssueIssue #1#1 of Volume 2. Are you bookkeeping $3.50$3.50 (this pays for the time andand suppliessupplies surprised? Not surprised because were here — but involved in entering your order into surprised to see us all neatly typeset — with a real the books, loading thethe rightright banners. We dodo wantwant to let you know that wewe discovereddiscovered program into thethe PET,PET, copying it,it, that one pagepage of of typewritten typewritten text text is is equivalent equivalent to to1/2 1/2 verifying it, loading itit into the page ofof typeset text —— so there's more material here second PET to to bebe suresure itit willwill work than waswas in anyany issueissue of VolumeVolume 1. HoweverHowever — we've on both versions of PET,PET, packing it changed aa fewfew things:things: up and shipping itit to you, entering First — there's no Flea MarketMarket programsprograms listed in this all the shipping data in the issue. ThereThere areare twotwo reasonsreasons forfor this:this: First, wewe plan to books. etc.) list thethe programsprograms only onon alternate months.months. WhenWhen we I couldcould break the "bookkeeping" down intointo "order can get a PET printer, printer, we'll well start printing more program entry, order fulfillment, officeoffice supplies,supplies, shipping. labor" listings, in thethe alternatealternate months.months. Second,Second, most of ourour etc., but I'm suresure that's not interesting or important.) SoSo FME programsprograms werewere contributedcontributed by a single individual. we have toto sort out the programs submitted by this This person hashas decideddecided thatthat we are not supposed to individual andand remove them fromfrom thethe FMEFME —— oror stopstop charge you $5.00 for aa FMEFME programprogram you want when "selling" programs to those ofof you whowho don'tdon't havehave you don't have a program to send to us in exchange. programs to exchange. By the way — our costs areare thethe We are permitted to continue to exchangeexchange programs same, whetherwhether youyou "buy""buy" or "exchange" aa program!program' with those of youyou whowho dodo havehave programs to sendsend us, Another change isis thatthat we've scatteredscattered youryour lettersletters over and our contributor himself charges the same $2.00$2.00 forfor the entire issueissue rather thanthan collectingcollecting themthem inin thethe PET PET expenses thatthat we do on exchanges. (Just(Just forfor interest,interest, Parade columns.columns. We electedelected toto do this because several our costs are: cassette $.50 of you have suggested thatthat it would be more interesting to have the pages "broken""broken" byby shortshort lettersletters ratherrather than SUBSCRIPTION, ADVERTISING, & have the pages fullfull of "unbroken" text. WeWe decided to MISCELLANEOUS INFORMATION try itit —— if wewe (and you) don't like it, wewe cancan changechange itit again.again.

THE PAPERPAPER is is published published ten ten times times perper yearyear by We dodo notnot knowinglyknowingly reprintreprint any material protected byby ARESCO, 616 616 Northampton Northampton Road, Norristown,Norristown, copyright. MaterialMaterial submittedsubmitted to to THE THE PAPER PAPER for PA 19401.19401. Mailed toto subscribers onon thethe last day of publication is considered free of copyright restrictions each month except July and December. Single and becomes the propertyproperty of of THE THE PAPER. PAPER. Any copy price isis $2.00,$2.00, subscription priceprice isis $15.00.$15.00. copyrighted material submitted must includeinclude Foreign $25.00. One subscription includes all ten permission toto reprintreprint thethe material oror itit will not be issues ofof oneone volume.volume. A subscription does notnot considered forfor publication. carry over from one volume toto another. Payment for subscriptions, software, hardware, and Subscribers wishingwishing toto orderorder lessless thanthan thethe fullfull tenten advertising orders must accompany the order. We have issues shouldshould remitremit $2.00 perper issueissue desired. no facilities for C.O.D. oror billing. Renewals forfor subscriptions are accepted from Advertising rates are: 1/4 page ..... $25.00$25.00 November 1, and the first issueissue of each volume is Advertising rates are: 1/4 published in February. Entire contents copyright 1/2 Page Page ...... $45.00$45.00 full page . $85.00 co1979 1979 by ARESCO.ARESCO.

Application to mail atat second-classsecond-class postage rates Advertisers should submit camera ready copy (not(not is pending in Norristown,Norristown, PA,PA, 19403. photocopies) in the exact page size of the ad. Payment POSTMASTER: Please Please send send addressaddress changeschanges to must accompany the copy. THE PAPER,PAPER, P.O. P.O. Box Box 43, 43, Audubon, Audubon, PA,PA, 19407. 19407. No more than 25% of the total pagespages of any one issue THE PAPERPAPER is is an an ARESCO ARESCO publication, publication, edited edited byby will carry advertising. CopyCopy should reach usus byby thethe 5th Terry L. Laudereau. ForFor furtherfurther information, day of the month prior to the month in which the ad is contact thethe Editor,Editor, THE THE PAPER,PAPER, P.O.P.O. BoxBox 43,43, to be published. Ad placementplacement isis onon aa first-come.first-come. first-first- Audubon, PA 19407. served basis. Subscribers wishingwishing toto submit software for Manufacturers of hardware, software, andand paperwarepaperware consideration in the Flea Market Exchange or or inin thethe for thethe PETPET personalpersonal computercomputer areare encouragedencouraged toto sendsend Software Shelf Library should send aa copycopy cfcf thethe us a sample of their products for review. TheThe product program and appropriate documentation toto the will be returned after 3030 days,days, but beforebefore 120 days,days, Software Editor,Editor, c/oc/o THE THE PAPER.PAPER. Programs accepted when accompanied byby aa letterletter requestingrequesting return.return. will not bebe returned. ProgramsPrograms accepted forfor thethe Software Shelf will bebe copyrightedcopyrighted by by ARESCO. ARESCO. PET isis aa registeredregistered trademark ofof CommodoreCommodore BusinessBusiness 20% royalties are paid quarterly on all Software Shelf Machines, Inc. THETHE PAPERPAPER isis notnot associated in any programs. A sample contract will be sent upon request. way with CommodoreCommodore and is not responsible for any action or inaction on Commodore's part. Commodore Readers areare encouragedencouraged to to submitsubmit articlesarticles ofof interestinterest to is not responsibleresponsible for any opinion or materialmaterial publishedpublished PET owners.owners. (See(See commentscomments regardingregarding copyrights, in THE PAPER.PAPER. above.) 2 Some of the articles in this month's issueissue are you want a complete set, the price is the same asas thethe symptomatic ofof yetyet anotheranother change. change. "A"A PETPET In TheThe price for Volume 2 — $15.00$15.00 for all 10 issues, or $2.00 Classroom", forfor example,example, andand anotheranother one,one, thethe titletitle of for aa singlesingle issue.issue. The last page in this issueissue (inside thethe which occupies more more than than two two typewritten typewritten lineslines ofof text.text. back cover) contains aa formform toto fill out and return. WhenWhen Neither of these articles contain "hard" factsfacts —— but we run out of Volume 1 sets, we'll just send your check they're both interestinginteresting andand thought-provokingthought-provoking —— andand back to you — or,or, if you order by credit card, we'll warrant responsesresponses from those ofof youyou whowho possesspossess an notify you that wewe aren'taren't chargingcharging youryour card.card. interest inin thethe topicstopics covered.covered. WeWe have yet anotheranother ofof This is the veryvery firstfirst issue issue of of THE THE PAPERPAPER sentsent to Roy Busdiecker's seriesseries ofof articlesarticles (and we'll have Commodore forfor comments beforebefore beingbeing sentsent toto press. another in this series nextnext month)month) — andand thethe "kick-off""kick-off" Robert Webb, of Commodore CANADA, offeredoffered to go to ourour IntroIntro To To MachineMachine CodeCode series — thisthis article was through thethe issueissue and offer commentscomments and suggestions. written byby GaryGary Maier and introduces youyou toto some ofof Since thisthis editorial is being written onon JanuaryJanuary 5th, andand the terminology. A lot of otherother goodiesgoodies areare insideinside we're going to press on January 15th,15th, I'm notnot certaincertain we invite your commentscomments and suggestions on even Robert will have time to get his comments back to us further improvements.improvements. for inclusion inin thisthis issue.issue. IfIf not,not, we'llwell includeinclude them in You shouldshould alsoalso notenote thatthat we've changed our policy #2. AndAnd wewe hopehope to bebe sendingsending Robert a pre-press regarding the number of pages ofof advertising.advertising. Many ofof copy of every issue ofof thisthis volume. If we're lucky, we you (and boy, was II surprised byby thethe number!) can resume our "From The Commodore" column! protested, saying thatthat you really enjoy reading By the way — have you noticed that some of the computer-related ads. Since the number of pages will "professional" computer magazines areare advertisingadvertising inin probably change from issue to issue, we've decided on our pages? IfIf youyou electelect toto buybuy oneone ofof themthem (or(or thethe a percentage (25%)(25%) rather than a flat numbernumber ofof pages.pages. software they offer) please don'tdon't forgetforget toto mention that This means thatthat in a 32 page issue, we might carry as you saw their adad inin THETHE PAPERPAPER — — in in fact, fact, ifif you many as eight pages ofof advertisingadvertising —— butbut thatthat inin a 16 purchase any item advertisedadvertised in in THE THE PAPER,PAPER, telltell the page issue, we'll only have four pages.pages. Many of you vendor where you saw his ad. And read Dennis chided usus forfor suggesting thatthat if we have a sufficient Costarakis's reviewreview ofof some ofof the vendors he's dealt number of subscribers,subscribers, we'dwe'd bebe ableable toto chargecharge lessless —— with .... thenthen sendsend usus reports of your experiences. IfIf as though wewe thoughtthought THE THE PAPERPAPER isis overpriced!overpriced! No, you are having trouble with a vendor, let usus know — we don't think itsit's overpriced overpriced —— but we'dwe'd rather makemake sometimes we can expediteexpedite thingsthings for you — or at least our profit onon volumevolume thanthan onon margin.margin. ThreeThree peoplepeople saidsaid find out what's going on! they'd be willing to paypay asas much as $25.00$25.00 for the ten issues! Hope you all had a happiest of holidays — andand thatthat you're all set for a super '79! We have a limited number of VolumeVolume 1 setssets leftleft —— andand a few odd copies ofof somesome ofof thethe issues inin VolumeVolume 1.1. IfIf

WHAT REALLY MAKES YOUR PET TICK? —— continued cards. If you stack one cardcard onon toptop ofof another,another, untiluntil the address onon thethe top of the stack.stack. TheThe stack pointer you have all the cards stacked on the table, then the is used toto determine whichwhich memorymemory locationlocation first cardcard youyou willwill bebe ableable to pickpick upup willwill bebe thethe lastlast oneone corresponds toto thethe toptop of the stack (technically, it's you laid down (you pick up the card fromfrom the top of the normally pointing at the location where the next entry stack). The stack pointer is used to remember an on the stack will go).go). TheThe stackstack isis alwaysalways stored in address toto which thethe program must return after page one of PET'sPET'S memorymemory (hex address 0100-01FF). completing a specific job. The stack is very handy The Processor StatusStatus RegisterRegister contains all the flags when you're using subroutines. TheThe address of the and status bits. It isis treated as a single 8-bit register for instruction whichwhich callscalls the subroutinesubroutine (in(in BASIC,BASIC, thisthis isis programming convenience, butbut eacheach bitbit reallyreally hashas itsits the line with thethe GOSUBGOSUB statement)statement) is placed onon thethe own meaning and itsits own set of instructions for testing top of the stack.stack. Then,Then, when all the instructions in thethe and being modified. Here are the names of the flags or subroutine have been executed, the program returns to status bits contained in the processor status register:

Carry Interrupt DisableDisable Decimal Mode Negative

Zero Break Command Overflow

Let's develop a simple programprogram to fill the toptop sixsix lineslines ofof thethe screenscreen withwith solidsolid squares.squares. AA BASICBASIC program to do this might look like:like:

10 FOR 1)1) TO 239239 Note that the variable "I" isis beingbeing usedused asas an 20 POKE 32768+1,160 32768+1,160 index (to helphelp calculatecalculate thethe locationlocation toto be be POKEd) POKEd) asas 30 NEXT I well as for a loop counter.

To write an assembly language program, youyou shouldshould havehave aa copy copy of of the the 6502 6502 OPCODE OPCODE reference card, whichwhich youyou should be able to getget fromfrom MOSMOS TechnologyTechnology or oneone ofof theirtheir dealers. dealers. The The OPCODES OPCODES (operation(operation codes) are mnemonic representations of the hex digits used to program thethe 65026502 inin machinemachine language.language.

First, let's decide whatwhat itit is we wantwant thethe programprogram toto do.do. 1. Load thethe white square (ASC 160)160) intointo the accumulator so we can transfertransfer it somewhere else later.later. 2. Load thethe XX indexindex registerregister withwith zerozero toto "clear"clear itit out".out". 3 3. Move the white square from the accumulator to the screen address 32768 + the value in the X register, soso wewe can put the square in more than one place on the screen. 4. Increment the X register 5. Check to see if the value in the X register is equal to 240. since we only want 6 lineslines (40(40 characterscharacters byby 6 lines = 240) on the screen. 6. If the value in the X register isn'tisn't 240, then wewe wantwant thethe programprogram toto gogo backback toto stepstep 33 7. If the value in the X register is 240, then wewe wantwant toto returnreturn toto BASIC.BASIC. So let's write the program: 1. LDA #160 (Load the accumulator withwith 160)160) 2. LDX #0 (Load the X index register with 0) 3. LOOP STA 32768,X (Store the value in the accumulator at screen address 32768+X) 4. INX (Increment the X index register by one) 5. CPX #240 (Compare the value in the X index register to 240) 6. BNE LOOP (Branch, if not equal, to instruction 3) 7. RTS (Return to BASIC) The "#" in front of the numbers 160, 0.0, and 240 is the standard way of indicating thethe immediate mode of addressing (that is, the values 160, 0 and 240 willwill bebe loadedloaded intointo thethe accumulator,accumulator, notnot thethe valuesvalues storesstores at at addresses 160, 0 or 240). The X index register is used as both an index (to helphelp calculatecalculate anan address)address) andand asas aa loop counter, just likelike thethe variablevariable "I""I" inin thethe BASICBASIC program.program. If you are lucky enough toto ownown anan assemblerassembler forfor youryour PET,PET, thethe jobjob isis finished.finished. Otherwise,Otherwise, thethe programprogram mustmust be be converted from assembly language toto machinemachine languagelanguage code.code. TheThe 65026502 OPCODEOPCODE card card will will give give you you the the hex hex values for each of the mnemonics we've used, but since thethe PETPET doesn'tdoesn't havehave thethe overtovert abilityability toto communicatecommunicate with people in either hex or binary, I will keep thethe programprogram inin decimal.decimal. Let'sLet's useuse addressaddress 65006500 forfor thethe startingstarting address of our program. Here it is,is. then:

ADDRESS MNEMONIC VALUE COMMENT 6500 LDA 169 Load accumulator . 6501 160 With 160. 6502 LDXLOX 162 Load X index registerregister 6503 0 With 0. 6504 STA 157 Store the value in the accumulator 6505 0 At address 32768+X (LSB) 6506 128 (MSB) 6507 INX 232 Increment the X index registerregister 6508 CPX 224 Compare the X index register value .... 6509 240 To 240. 6510 BNE 208 Branch if not equal . 6511 248 To address 6504 6512 RTS 96 Return to BASIC

The "values" here represent the decimal form of the OPCODES. The two bytes (at addressesaddresses 65046504 andand 6505)6505) representrepresent the absolute address to which the value in the X indexindex registerregister willwill bebe added.added. WhenWhen specifyingspecifying anan absoluteabsolute address,address, thethe least significant byte ofof thatthat addressaddress (LSB)(LSB) isis alwaysalways enteredentered first,first, andand thethe mostmost significantsignificant bytebyte (MSB)(MSB) isis enteredentered second. The absolute address (in this case, 32768) can be calculated using the following formula: Address = LSB + 256*MSB And you can find the LSB and the MSB with these formulas: MSB = INT(address/256) : 128=INT(32768/256) LSB = Address-256*MSB :: 02768-(256*128)02768-(256 -128) In location 6510, the BNE (branch if not equal) instructioninstruction usedused aa modemode ofof addressingaddressing calledcalled relative addressing. This means that the address to which the program will branch must be calculated and given in terms of its positionposition relativerelative toto the BNE instruction. WeWe cancan branchbranch asas manymany asas 127127 bytesbytes forwardforward oror backward,backward, andand inin thisthis case,case, wewe wantwant toto movemove backward to address 6504, or 8 bytes. Remember,Remember, thethe programprogram countercounter Isis alwaysalways pointingpointing toto thethe nextnext instructioninstruction to to be be executed, so it is pointing to 6512. 6512 - 6504 = 8. Because we are moving backward, an unusual method is used to calculate the number of bytes to be moved. It's calledcalled "two's"two's complementcomplement arithmetic".arithmetic". TheThe two'stwo's complementcomplement ofof anyany number is found by adding one to the one's complement. TheThe binarybinary representationrepresentation ofof 88 isis 00000000 1000.1000. TheThe one'sone's complement is 1111 0111 (all thethe 0'sO's become become 1 l's, 's, and and allall thethe l's1's become become O's). 0's). Then Then add add 1 1 (in (in binary) binary) to to get get 1111 1111 1000.1000. ThisThis is 248 in decimal. IfIf you'reyou're confused, aa goodgood bookbook onon binarybinary arithmeticarithmetic cancan help.help. ItIt isn'tisn't complicated,complicated, butbut itit is new to you.you, and a local computer store will carry several books on the subject. 4

The following BASIC program will load the machine language programprogram intointo thethe selectedselected memorymemory locationslocations forfor you Look at the data in the DATA statements, and see how they correspond to the program we just wrote,wrote. 10 DATA 169,160,162,0,157,0,128,232,224,240,208,248,96 2C FORFOR J=6500 ,1500 TO TO 65126512 3C READ I 40 POKE J,IJ,i 50 NEXT J 60 END

2-w'After running running this this BASIC BASIC program, program, the the machine machine language language program cancan be be executed executed by by typing typing in inSYS(6500). SYS(6500). The The Ev'SBYS tmrnand command will transfer will transfer control control of the of thePET PET to yourto your machine machine language language program. program. When When the the RTSRTS is'executed,is executed, *nil be transferred back to BASIC.

Multipleleurtipöt Precision Arithmetic -=Programming- 7,.: -arnming in machine language can be fun, if you don't mind having to do the assemblingassembling byby hand.hand. -t.ssembling"Assembing" in ourin our case case means means converting converting the the program program from from the the assembler assembler language language mnemonicsmnemonics toto the decimal recognized by the PET. MostMost booksbooks onon microsmicros carrycarry aa sectionsection onon convertingconverting hexhex valuesvalues toto decimaldecimal values, values, butc.-t you can just look it up in issue #2 of THE PAPER. The following program isis inin assemblyassembly language,language, andand youyou can convert it to decimal and try it out if you like. The program adds two 16-bit numbersnumbers together.together. Ifif we added only 8-bit numbers, we could only add upup twotwo numbersnumbers lessless thanthan oror equalequal toto 255!255! So,So, forfor thethe firstfirst number,number, we'll we'll call the LSB L1.Li. and and thethe MSBMSB Ml.Ml. ForFor thethe secondsecond number,number, thethe LSBLSB isis L2,L2, andand thethe MSB is M2. Then, for the result, the LSB is L3, the MSB isis M3.M3. YouYou cancan plugplug anyany numbersnumbers inin andand getget whateverwhatever isis thethe appropriateappropriate result. result. Remember — to run the program, you must first look up the hex codes corresponding to the mnemonics onon thethe OPCODE table. Then you have to convert the hex values to decimal, enter the decimal values into DATA statements in a BASIC program, RUN thethe program,program, thenthen dodo aa SYSSYS toto thethe addressaddress intointo whichwhich youyou poked poked the the data. data. LSB MSB FIRST NUMBER L1 M1 Second Number L2 M2 Result L3 M3

Mnemonic Value Comment CLC CLC Clear the Carry FlagClear the Carry Flag kt LDA L1 Load the least significant byte of the firstfirst numbernumber into the accumulator. ADC L2 Add L1 to the least significant byte of the secondsecond number.number. If the result is greater than 255, set thethe carrycarry flag.flag. STA L3 Store the result in memory LDA M1 Load the most significant byte of the first number into the accumulator ADC M2 Add M1 and the value of the Carry Flag to the most significant byte of the second number. STA M3 Store the result in memory.memory.

The ADC instruction adds the value in the addressed memory location and the value of the Carry flag to the valuevalue in the accumulator. TheThe resultresult isis storedstored inin thethe accumulatoraccumulator andand thethe oldold valuevalue isis discarded.discarded. IfIf thethe resultsresults ofof thethe addition exceed 255, the Carry flag isis setset (its(its valuevalue becomesbecomes 1).1), SinceSince wewe don'tdon't know,know, beforebefore wewe start,start, justjust whatwhat the value of the Carry flag is, we use the CLC command to setset itit toto zero.zero.

Y ou can do multiple precision subtraction inin aa similarsimilar manner,manner, butbut rememberremember thethe businessbusiness ofof "two's"two's complementcomplement arithmetic".artrimetic". TheThe SBCSBC instructioninstruction willwill addadd thethe CarryCarry bitbit valuevalue toto thethe complementcomplement ofof thethe addressed memory location, and that result to the valuevalue inin thethe accumulator,accumulator, discarddiscard thethe oldold value,value, andand storestore thethe resultresult inin thethe accumulator. SEC Set the Carry flag LDA L1 Load the LSB of the first number SBC L2 Subtract the LSB of the second number from L1 STA L3 Store the result. The carry flag is reset if it's necessary to borrow. LDA M1 Load the MSB of the first number SBC M2 Subtract (remember the borrow!) the MSB of the second number from M1 STA M3 Store the result in memory.

5 Debugging

Bugs in a machine languagelanguage programprogram areare veryvery difficultdifficult to find, becausebecause they usually cause a system crash. The easiest wayway toto trace the problem is to insert the RTS instructioninstruction intointo various placesplaces inin thethe program.program. ThisThis way,way, youyou can tell how far your programprogram getsgets beforebefore itit crashes.crashes. YouYou can also examine thethe registers to be sure your program is doing what you want it toto do.do. BeBe careful,careful, though,though, becausebecause when youyou removeremove thethe RTSRTS instructions, instructions, youyou havehave to to put something in their places.places. A machine languagelanguage programprogram cannotcannot havehave "empty "empty bytes"bytes" inin it.it. You cancan insertinsert aa NOP (no(no operation)operation) commandcommand inin allall thosethose places,places, however,however, andand itit will solve that problem.

Adding instructionsinstructions in the program must be done carefully, since itit means thatthat all the instructions following it willwill have to be relocated. An assembler cancan dodo thatthat task for you, and if you'reyou're seriouslyseriously interestedinterested inin machinemachine language programming,programming, I recommendrecommend thatthat youyou getget anan assembler.assembler. ItIt will will save save you you hours hours of of converting converting mnemonics mnemonics to hex to decimal!

MORE PROGRAM LISTINGS? REVIEW — BETSI (from Forethought Products) Ron LongfellowLongfellow writes:writes: HaveHave youyou thoughtthought ofof allottingallotting by Wayne Reindollar space toto printingprinting out listings of programs submittedsubmitted toto the FleaFlea Market — general games, business programs,programs, etc., instead of just listinglisting thethe namesnames ofof thethe programs?programs? I I consideredconsidered getting aa memorymemory expansionexpansion for mymy PETPET consider myselfmyself aa novice,novice, butbut eveneven 1I could dream up and decided on the BETSI fromfrom Forethought Products. programs for most of the titles inin thethe Exchange!Exchange! The I orderedordered mymy BETSIBETSI kit from ABAB Computers along withwith first thingthing II dodo whenwhen II pickpick upup aa computercomputer magazinemagazine or a power supply. The boards I plan toto useuse onon thethe BETSIBETSI publication is to flip through it, lookinglooking forfor useableuseable only require +8 voltsvolts unregulated,unregulated, soso ABAB ComputersComputers programs. You would certainly boost your circulation made a power supply for this need. The BETSIBETS! kitkit andand by becoming known asas thethe bestbest sourcesource forfor PETPET power supply arrived about seven days after ordering. program listings around! Maybe 33 or 4 listings per The BETSIBETS! assembly/operatingassembly/operating manual was very issue, using PET's specialspecial features, features, etc.,etc., wouldwould be a informative andand gave good hintshints on assemblingassembling thethe kit.kit. real selling point. You couldcould rewardreward aa contributorcontributor withwith I orderedordered three extra 5-100S-100 edgeedge connectors withwith mymy free Flea MarketMarket programs.programs. I'dI'd contribute! kit so I couldcould assemble thethe wholewhole kitkit atat oneone time.time. I We've considered doingdoing justjust that,that, but withoutwithout thethe PET PET followed the testing procedureprocedure after assemblyassembly and all printer, (and(and sincesince many of the cursorcursor control seemed toto be in order. Assembly andand testingtesting were characters don'tdon't printprint at all on our printer)printer) it'sits difficult accomplished in one evening. to list programsprograms that willwill bebe useful.useful. However, we'rewe're The memory board I selectedselected was the GodboutGodbout working on it. ByBy thethe way;way: FleaFlea MarketMarket programs are Econoram IIII Un-Kit which has 8K of memory. The essentially free to anyone who contributes a program. board arrived ten days fromfrom thethe timetime II ordered.ordered. TheThe Un-Un- We chargecharge $2.00$2.00 (for(for time, packaging, postage. etc.)etc.) Kit version has all the IC sockets and all the by-pass per program — and just break even. If someonesomeone wants capacitors soldered in place. The onlyonly soldering that to buy aa program from thethe Exchange,Exchange, we chargecharge $5.00$5.00 had to be done was toto install two voltage regulators, — andand thethe extra $3. is used to buy a little more time soso two slideslide switchesswitches and four capacitors.capacitors. ThenThen came the we can do some programprogram developmentdevelopment (we(we contributed tedious jobjob of inserting 75 IC packs. Codes, States & Capitols, and a few others) ourselves.ourselves. The Flea MarketMarket isis intended to be an openopen exchangeexchange — Upon completioncompletion ofof everything,everything, I turned thethe powerpower offoff and we exchange more than twice as many FM the BETS'BETSI and the PETPET asas isis recommendedrecommended inin thethe programs as we sell. Yet, our usual shipment ofof FMFM BETSIBETS' manual.manual. I inserted the memory card in the programs in any one month isis underunder 2020 tapes!tapes! PET PET BETSI andand attachedattached the BETS'BETSI to the PET viavia thethe users are getting more sophisticated and want memory expansion port. On power up to the BASICBASIC something more than adaptedadapted TTYTTY programs, adapted printed 1535915359 BYTESBYTES free. arcade games.games, and adapted pen- andand pencilpencil gamesgames —— On the BETSIBETS' boardboard therethere isis enoughenough roomroom toto mount a even in exchange! push button switch close to the edge connector. II did We've also hadhad aa considerableconsiderable bit bit ofof difficultydifficulty with this and wired one side toto ground and thethe other side toto people who reallyreally want to exchange programs,programs, butbut whowho the pinpin A27,A27, resetreset lead.lead. ThisThis wayway II cancan resetreset thethe PET PET haven't written anyany —— soso theythey sendsend usus someonesomeone else'selse's without power down. copyrighted material! OfOf coursecourse wewe can'tcan't acceptaccept itit —— but it takestakes timetime toto gogo throughthrough 2121 programsprograms onon aa singlesingle tape and determine whether they'rethey're allall copyrightedcopyrighted —— or whether the "contributor" made aa littlelittle efforteffort him/herself. Micro Software Systems, P.O. Box 1442, Woodbridge, VA 22193 announces SWEE-PING —— a a ball-bouncingball-bouncing game that gives the player full directional control. Dean HillsmanHillsman writes:writes: I'm greatly puzzledpuzzled about the Instructions are built into thethe programprogram soso you can't lose relative unavailability ofof anan interfaceinterface betweenbetween thethe PETPET them, andand the ballball goesgoes where you direct it byby usingusing and the IBM Selectric typewriter. ConsideringConsidering the the number keypad. The flyerflyer received indicatedindicated thatthat atat availability and power of this hard copy device, I least three games areare availableavailable —— atat $5.95.$5.95. WriteWrite toto Roy wonder why someone hasn't made the connections. Busdiecker forfor fullfull information.information. Anybody out there havehave anyany suggestions?suggestions? 6 •

SoftwareSawyer

aCCOul(reitGaCCOLACTING PACK 11 — - Business SoftwareSoftware for your 8K PET tm PAYROLL-PAYROLL— a=za.--a=za.,-- Pack I1 isis aa generalgeneral ledger package Especially designeddesigned with with thethe small businessmanbusinessman In In `x smallsmall businesses businesses and and homeownershomeowners mindMind Utilizing cassettescassettes cancan recordrecord data for any - :neck journal,journal. general ledger, incomeincome number of employees (8(8 employees perper cassette). cassette) sase-csane-r- • ic.irrentlox-rent yid,yid, previousprevious month yid and Computes taxtax information and updates totals for *** NEWNEW* **** * * *quarterly * and yearly reports. Employees canCan bebe =-T-e- - -arm),cn1b), balance sheet (current month and a-ewcasS.:Ma -north).With). There are 15 commandscommands and 6 salaried or hourly and pay periods can bebe eithereither aria-eccr-s 7atar- can can be be generated. generated. TheThe system uses an ACCOUNTING PACK II — - weekly, bl-weekly, semi-monthly or monthly. s:^gle-entrys.-+ re-entry bookkeepingbookkeeping systemsystem and can Accounting PackPack II II Is aa muchmuch more powerful versionversion 130.00530.00 -roc _c '7. 5C5C entriesentries, per per period period (month, (month, week, week, day)day) of Accounting Pack Pack I. I. It hashas allall thethe featuresfeatures of ac=arc 410 different40 different accounts. accounts. Each Each period's period's Accounting PackPack I, I, plus upup toto 250250 entries per period, seaaria aa •so!•rr on on convenient convenient cassette cassette tapes.tepee. Utilizing MENU, Optional debit.creditdebit-credit of entries, easy addition -e arraar-a- raper-,te ledger command command the the user user can can view view the or deletion of accounts, formatterformatter forfor reports,reports, intelli-intelli- sowswhe-a edger eager entriesentries forfor thethe monthmonth fromfrom AssetsAssets gent report generator and single entry for sales BUSINESS GRAPHICGRAPHIC PACK PACK 1 1 — - c -sea oror stop stop inin midstreammidstream and view one transactions. Accounting Pack Pack II II requires at least 8K Business GraphicGraphic PackPack 11 isis aa simplesimple programprogram to use. r-c...-ara- accountaccount Or the user can type In anan accountaccount additional memory for your PET. OPTIONS: 1.1. but professional in output. The graph includes title.title. -ar-e-arne asas • - Advertising"Advertising - andand view the entries Accounting PackPack I I toto AccountingAccounting Pack Pack II II datadata filefile labeling of axis,axis, dualdual graphicgraphic lability,ability, whetherwhether thethe -*me.^_min- TheThe AccountingAccounting Pack 1I program converter (free toto previousprevious ownersowners of Accounting data is Inin Mill's, 100'a100's or 1000's. andand anan optionaloptional rcn •c•cee _cis aa nearbooknecktook reconcilationreconcilation routineroutine which aids Pack I), x-axis datedale and labeling ofof thethe x-axisx-axis withwith monthmonth --; o‘eclibook•neclitiooir errors.errors. Sawyer SoftwareSeltesrs plansplans 545.00$45.00 and year. Entry le as easyeasy asel typing thethe title,title, if1 ofof 1aQEII_12•=264 I: accountingAccounting Pack Pack 1 tolo enable the user to entries, the X,Y value (Jan. 15, 1978 wouldwould be -seAR a p-p-, -,rerter floppytlOppy diskdisk oror moremore memory.memory. Account- entered asas 115.78), 115.78), entering entering if ifthe the x-axle x-axle = dale, ifif PiaPea is wellis well documented, documented, with with a a newly newly updatedupdated the useruser wants crceshatching andand thenthen graphing _sr marual.vianual. Several Several businessmen businessmen are are usingusing The program also Includesincludes Nth order and Geometric regression toto givegive thethe useruser aa formulaformula forfor hishis setact ofof • .-c Pack I1 andand havehave writtenwritten to us their BUSINESS ANALYSISANALYSIS — - ler.rcs s-sc7crac.cr with with thethe programprogram alongalong withwith theirtheir data (if possible). Business AnalysisAnalysis allowsallows managementmanagement to have 125.00825.00 • clothierof other software. available toto themthem InformationInformation fortor financialfinancial planningplanning 123.03 525.03 decisions. UpUp toto 44 years of balance sheetsheet andand incomeincome statement information can be entered with resultant analysis in the areas of liquidity, leverage, profit- ability and activity. The retireratite generated for eacheach ICHIEOL/LEICPIEDULE PLANNER PLANNER - CHECKBOOK RECONCILIATIONRECONCILIATION — - i...-horp-e manneraririer can be used by secretaries, year are the: current ratio, acid test,test, debt-nw,debt-nw, prof it-nw, profitprof it margin, margin, saies-rec,sales-rec, sales-inv, Designed for ease of use and toto find threethoee trouble-trouble- erecror•stscircrcr sts NOUSeftIVIMI housewives oror anyoneanyone wantingwanting toto planplan some checkbook errors,errors, this program balances youryour a!a7: sales-wc,sales-we, with a brief explainationexplaination ofof each.each. The sac-c -a+e , their fingertips their own schedule. DataData checkbook and bank statement from month to month. growth analysis gives thethe yearlyyearly growth In 5 areasareas wee 2 data3 seta- time, time, priority priority and and description description. TheThe It11 locateslocates overover tenten differentdifferent typestypes ofof errorserrors andand and the average growth In 55 areas.areas. FutureFuture growth Meowallow thethe schedule schedule to bebe shown for a instructs the useruser onon correctingcorrecting them,them, includingincluding bankbank analysis projects figures forfor the next year,year. request of time or the "viewing - of statement errors mademade byby your bank. RecordsRecords data on 1 590.00 coos--ems accordingacearding to importance. 130.00 cassette for next month's balancing -- saving re-entryre-entry $15.00S15.00 of figures.figures S115.1105555.00

sL7£7t/tE PLANNER 1212 — FINANCIAL PACK PACK II — - SC41110.*. PennerPanne- 12i12 includes includes all all the the featuresleeturee of Financial Pack I includes Amortization Schedule, Scum:Lae'tanner.ianner. butbut isis used for one or moremare Calendar (which figures daysdays between twotwo dales)dales).• CALCULATOR — - Especially forfor thethe accountant-bockkeeper.accountant-bookkeeper This incr--ci,..as utilizingunitizing Schedule Schedule PlannerPlanner #2 a customerCualOrner Rebate (which is calculated onon thethe FluteRule of 76's),78'51, program not only allows your PET toto function asas a car - airingasking when when hishis appointment withwith Dr.Dr. Compound, Annuities and Monthly payment,payment $15.00515.03 calculator, but also has such features as Lister (which 46-,,MIaI 2 sarc arc ^ Waldsseconds the the receptionist canCan give give thethe seesea arc ---re Or OrDr DrJones Jones can can find find out out his his scheduleschedule verifies and displays errors betweenbetween twotwo tapetape listings)listings) and Matrix (which addsadds columns vertically and cr• 2.-* Mtnma. Mtnthe theviewing viewing command, command, an appoint- or-- aa - 2 -X onor aa particularparticular day will display on the horizontally). a: $1510.000.00 =Nor r roarr"al- timetime allowing allowing receptionistsreceptionists and CHESSBOARD — - IMIL—WW- ee t .aldate, aAidateappOintMents. appointments. Chessboard allowsallows two players to play chess on your 120-00120.00 own PET graphic chessboard. ThisThis programprogram displays each player's timetime andand recordsrecords each each move move to to meow allow you to playback thethe gamegame atat anotheranother time.time. All Programa include documentation.documentation, are In BASIC =NOWIG=11111114 SOON SOON — - $15.00 and on cassette. isseiressilsontles SriSri-ware- ware for your 16K TRS-80. WriteWrite or callcail war aeceZera Z arc a.anability&reliability

•'PETPET is a trademark of of Commodore Commodore Business &Airless DenierDrier inquiresinouiree invIted_Invited Machines,

Sawyer Software

201 Worley Road Dexter, Mo. 63841 314-624-7611 ANOTHER MICROCHESS REVIEW that thethe 5-pin5-pin power-feedpower-feed plug to thethe circuitcircuit boardboard was getting quite warm,warm, ThisThis is the disconnectdisconnect plug from the transformer && filterfilter condenser.condenser. I shimmedshimmed oneone of by John Hirsch the connector spring pins and operation returned toto I purchasedpurchased PersonalPersonal Software's Microchess 2.02.0 tape normal.normal, No more heat build up in thethe connectorconnector andand recently and waswas surprisedsurprised to to find find that that itit playsplays aa pretty pretty the symptom of dropping the cursor at low voltages good game of chess. There are supposedly 8 levels of play, has been eliminated.eliminated. ItIt tolerates an input voltage as low but the differencesdifferences between intermediate levelslevels are not as 102vac withwith no tendency toto drop out when a discernible. AtAt levellevel 1,1, itit plays very rapidly, but doesn't cassette is used. Apparently a normal PET withwith good look very far ahead.ahead. Nevertheless, II findfind itit more difficult toto power plug connections willwill operate down in the beat Microchess LevelLevel 1 1 atat rapid-firerapid-fire chess withwith a 10- neighborhood ofof 100100 volts.volts. It'sIts entirely possible thatthat second timetime limitlimit thanthan toto beat levellevel 88 withwith aa 22 hour,hour, 40-40- other users could experience cursorcursor lock-outlock-out atat normal move limit. Level 8 is pretty strong tactically, but voltages, such asas II had today.today. In such a case, itit somewhat lackinglacking inin long-rangelong-range strategy.strategy. II particularly wouldn't hurt to check the temperature ofof thethe 5-pin5-pin noted that Level 8 handles rooks poorly,poorly, often leaving power supply plug on thethe circuit board! them undeveloped oror placingplacing them them irrationally. irrationally. It'sIts alsoalso a pawn-grabber — andand cancan be be diverted diverted from from aa potentiallypotentially winning attack if you throw it aa pawn.pawn. According to Gerald Balzano, here's a quick and easy way to program aa round-offround-off functionfunction fromfrom INT.INT, ItIt will Level 8 seems to favor certaincertain openings,openings, suchsuch asas thethe RuyRuy round any argument toto the nearest integer,integer, rounding Lopez andand Queen'sQueen's Indian, Indian, whichwhich (I(I believe) were the up from .5 or greatergreater andand rounding down otherwise. standard openings inin thethe originaloriginal Kim-1Kim-1 programprogram writtenwritten by Peter Jennings. WhenWhen playingplaying black,black, itit never responds 1 P-Q4 to white'swhite's 1 1 ...P-Q4. P-04. You You can can force force it it to to dodo soso byby making the move for itit andand thenthen seeingseeing howhow itit respondsresponds to DEF FNROU(A)FNROU(A) = = INT(2*A)-INT(A)INT(VA)-INT(A) roundsrounds toto nearest nearest integerinteger a Queen's GambitGambit opening.opening. ItIt always takes the pawn DEF FNRHF(A)FNRHF(A) = = FNROU(2*A)/2FNROU(2*A)/2 roundsrounds toto nearest halfhalt (usually not aa goodgood idea)idea) andand thenthen developsdevelops its QueenQueen DEF FNTEN(A)FNTEN(A) = FNROU(10'A)/10 FNROU(10'A)/10 rounds to nearest tenthtenth prematurely — rapidlyrapidly gettinggetting itself into trouble. FNROU cancan bebe usedused toto roundround toto anyany fractionfraction the user desires. The program is in machine code and no listing is supplied. The PET will will onlyonly listlist the SYS commandcommand whichwhich initiatesinitiates the machine code, andand onceonce thethe programprogram isis running,running, thethe STOP key key is is disabled. disabled. It It isis understandableunderstandable that that thethe authorauthor of the program would attempt toto preventprevent itit beingbeing copied,copied, PET PROSE but disappointing that thethe useruser hashas no chance to play around and modify it. (Of(Of course,course, one can always getget There are many people who want specializedspecialized around these restrictions.) application programs to use on their PETs, butbut whowho areare All in all, I thinkthink MicrochessMicrochess 2.02.0 is well worth the money— not knowledgeable enoughenough toto designdesign oror toto writewrite them. especially whenwhen comparedcompared toto the "dedicated" If youyou cancan write significantsignificant softwaresoftware inin somesome microprocessor chesschess games games retailing retailing at at up up to to $300.$300. II specialized field,field, and areare willingwilling to do so.so, we may be haven't had the chancechance (yet) toto playplay Microchess Microchess vs. ChessChess able to help you find the people who are willing to pay Challenger oror Boris,Boris, butbut II suspect itit would do very well. you to write programs for them. Send $25. with your name, address, andand fieldfield ofof expertise.expertise. TheThe informationinformation will be published in all the remaining issues ofof thisthis Jim Parr writes:writes: You should havehave toldtold Dave ConleyConley thatthat volume. he can use lower case or graphics inin REMREM statements, if hehe puts them in quotes.quotes. As usual.usual. thethe finalfinal quotequote onon WES FASNACHTFASNACHT (215) (215) 436-2886436-2886 the line is optional. That is, if youyou enterenter West Chester State College West Chester, PA 19388 100 REM "A"A Remark In UpperUpper && LowerLower CaseCase • Programming & Systems Development then the listing will looklook just likelike thatthat insteadinstead ofof beingbeing expanded into BASIC keywords.keywords. ButBut rememberremember toto Gregory Sheff POKE 59468,14l59468,14! 2207 South 82nd St. West Allis, WI 53219 • Business && EducationEducation (12(12 yrs exp) C.K. Wheeler commentscomments regardingregarding thethe letterletter he sent in last issueissue regarding thethe PETPET RAMRAM failuresfailures andand voltagevoltage Don Pegnataro symptoms: ThatThat RAMRAM failures can be relieved by lower 1420 Centre AveAve #1907#1907 voltages and cooler airair is,is, II am sure, a valid finding. Pittsburgh,Pittsburgh. PAPA 15219 The symptom of cursor drop-out below 112 volts • Education, Engineering.Engineering, BusinessBusiness should be modified, however, even though that waswas • Games, Photographic applications what was happening lastlast week.week. II started noticing an increased tendencytendency forfor "lock-up""lock-up" atat even higherhigher Because we missed printing PETPET PROSE in in issuesissues #7#7 voltages (113, 114, 115).115). AndAnd II recalled recalled somesome weeksweeks and #8, wewe will will print print the the names names of of PET PET PROSErs PROSErs in thethe back, when I was getting goodgood operationoperation withwith asas lowlow asas first twotwo issuesissues of Volume 22 oror refundrefund eacheach ofof themthem 1/51/5 107 volts. I thought maybe the filter condensercondenser might of the money they paid for insertion. be losing capacity,capacity. butbut it checked outout okay. I noticed 8

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Computers Calculators

We know that some magazines tend to ignore the computer novice. Some magazines assume you are a trained computer expert or aa veteranveteran Calculators/Computers Magazine also includes — hacker"! Well. we're different.. how-to articles for your calculator... Don't miss out on our back issues too! At CALCULATORS/COMPUTERS Magazine we know these things and understand your Please enter my subscription for: needs. We like to call ourselves a how-to- enter my subscription for: q do-it magazine for people like you-- beginners 1 q Special Introductory Offer --3 3 issuesissues for S5 • q and intermediates who want to learn how to q 1 year (6 issues) $10 q use. program and enjoy all kinds of calculators q 2 years (12 issues) $18 and computers. We especially want to help you q Back Issuesissues $2 each getvet more of everything out of your Commodore q Vol. 1, Issue 1 0q Vol. 2, Issue 3 PET. q Vol. 1, Issue 3 q0 Vol.Vol. 2, IssueIssue 4 q Vol. 2, Issue t q Vol. 2, issue 5 q Vol. 2, IssueIssue 2 q0 Vol.Vol. 2,2, IssueIssue 6 Not only will CALCULATORS/COMPUTERS Foreign rates additonal. Subscriptions begin Magazine help you learn how to program in with the currentcurrent issue. U.S. Currency please. BASIC on your PET, we'll continually provide you with: q Check enclosed 0q billbill meme (SI(S1 billingbilling fee 171q Mastercharge Mastercharge q BankAmericard • games and simulations - highly graphic Card No. No Rainesgames writtenwritten by Mac Oglesby for the PET i Exp.Exp. date date n ■ introductory and intermediate programmingprogramming NameName_ on the PET ■n BASIC for Parents andand TeachersTeachers -- ongoingongoing Address series beginning with the February 78 City issue (Vol. 2. Issue 2) State Zip ■n continuing lists of program sources • home uses for your computer Please send all orders to: • ways to share your computing know-how with family and friends • • • dymax, p.p. o.o. boxbox 310n,310n, menlomenlo park,park, caca 9402594025 I A MICROPROCESSOR IS A UNIVERSAL Technologically, thethe electronics industryindustry is capable ofof ACTIVE DEVICE HAVING A TRANSFER putting a "logic machine" into every home at a reasonable priceprice (under(under $700).$700). But the devicedevice will FUNCTION WHICH CAN BE ALMOST remain a "games arcade" until useful applications ARBITRARY DEFINED 1 programs are written to controlcontrol inexpensiveinexpensive peripheral Or devices. As longlong as peripheralperipheral equipment costs remain at their present levels with respect to the cost of the "BUT WHAT DOES IT DO?" computer, and application programs consists of Biorhythms, Star Wars, and calculating the cost of a mortgage, we'll have a lot of computer owners who will Have youyou everever writtenwritten a programprogram thatthat you thought was be asked, "But what does it do?" neat" — or even "clever"?"clever"? InIn fact,fact, you thoughtthought the program was so great that youyou decideddecided to show some So what's the answer? Being neither a hardware nor of your non-computing friends just how fantastic it software engineer, butbut aa computercomputer user,user, II willwill step intointo was! a no-man's land of thesis and postulate my ideas.

Here's the scene: your PET isis pluggedplugged in,in, poweredpowered up.up. I thinkthink thethe computercomputer shouldshould return to the "Black Box" You keykey in "Shift/Run" andand thethe displaydisplay reads,reads, "PRESS"PRESS concept and be located somewhere in the basement PLAY ON ON TAPE TAPE #1". #1". You You promptly promptly obeyobey thethe command (store in aa cool, dry place).place). MyMy system would be a time- — and then youyou w-a-i-t. w-a-i-t. "FOUND "FOUND INVSORHYPERTOTE" INVSORHYPERTOTE" sharing micro-computer with its background program flashes onon thethe screenscreen andand again,again, you you w-a-i-t. w-a-i-t. and operating systemsystem inin ROM ROM oror PROM.PROM. All the basic Eventually, the programprogram loadsloads andand executesexecutes the inverseinverse control and housekeeping routines would be in square of the quadratic surface of a hyperbolic totem ROM/PROM and and the the user user would would simply simply keykey inin thethe Polepole and the cursor reappears and flashes merrily variables thatthat apply to his/her system. 3 below a screen full of alphanumeric characters and In thethe familyfamily roomroom (or wherever)wherever) would be anan "READY".- READY". You You turn turn to to youryour friends,friends, face beaming, inexpensive videovideo terminalterminal thatthat enables thethe useruser toto awaiting accolades. andand youyou w-a-i-t.w-a-i-t. monitor processes, keykey inin newnew data, play games or Friend HenryHenry isis thethe firstfirst to respond, "But what does it receive the electronic newspaper from thethe cablecable TVTV do?" without haltinghalting thethe backgroundbackground program. ThereThere are micro-computers on the market that can do all of the Only slightly daunted, youyou proceedproceed to explainexplain howhow youyou above, but the cost of such a system is well beyond the have increased thethe executionexecution timetime byby a factor of 1000 range of a "useful, do something" home computer. over an equivalent BASIC program, by usingusing machinemachine language routines.routines. Also, ifif you had a disk system and a The manufacturers ofof micro-computersmicro-computers areare certainlycertainly printer, thethe programprogram wouldwould loadload fasterfaster andand you could not helping the situation. Of the three most popular have hard copy of all the data that scrolled off the micros (APPLE II, II, PET, and and TRS-80), TRS-80), none none ofof themthem screen. And, ifif you were a maker of totem poles,poles, you interface with thethe realreal worldworld inin thethe samesame way.way. NoneNone of could use the program to compute a theoretical model. them can communicate withwith the others, and with thethe exception of the PET, theythey do notnot comply with any Friend Mary replies. "Yes! But what does it do?"do?" standard bus structure. What more can you say? How do you explain a The reason, ofof course,course, isis obvious.obvious. Profit! Profit! WithoutWithout profit,profit, program that worksworks but doesdoes not physically show that no company will remain in business for very long. As something is being "done", i.e., something useful? long as you,you, the purchaser, areare boundbound toto theirtheir This question appliesapplies notnot onlyonly toto your non-computing peripherals, they will make a profit on the higher friends, but appliesapplies equally well to the micro-computer margin add-ons. It may take an Act of Parliament (or(or owner who purchased a "complete" system and Congress) toto bring some sense andand standardsstandards to to thethe expects itit to "do something". home computer market,market,*

It's aa difficult task to explain toto the novice thatthat aa It wouldwould bebe nicenice if allall thethe homehome computerscomputers thatthat useuse aa computer is really aa "dumb"dumb device"device" andand thatthat you,you, thethe CRT displaydisplay andand anan ASCIIASCII keyboardkeyboard used the same owner, are responsible forfor thethe programsprograms thatthat make it method for communicating between the keyboardkeyboard and "do something". NotNot onlyonly areare youyou responsibleresponsible forfor the computer.computer. AlthoughAlthough thethe RS232CRS232C serial programming, but also forfor thethe printer,printer, memory communications interfaceinterface willwill probably notnot be around expansion.expansion, disk storage system, and all the other in a few years.years. somesome such similarsimilar method should be hardware that interfaces withwith the world we live in. standard for all manufacturers. 5 6 In that way,way, youryour micro could serve asas aa terminalterminal forfor a host system, a The marketing people atat RadioRadio Shack and at terminal for thethe electronicelectronic newsnews services, etc.etc. Commodore are doingdoing aa finefine job of selling their so- called "convenience computers".computers". AtAt last report.report, Believe me. if the electronicelectronic newsnews serviceservice ever becomes Commodore isis saidsaid toto bebe producingproducing 45004500 unitsunits per interactive, homehome owners areare notnot going toto want two month, and starting toto produceproduce almost 1000 units perper computer devices in their homes. Two color television month at their facilities in the U.K. 2 Radio Shack is sets, yes. TheyThey dodo something! But two displaydisplay devices reported to bebe outproducingoutproducing CommodoreCommodore by a factor that appearappear to do the same thing?thing? II doubt it! of 2:1. I thinkthink homehome computerscomputers shouldshould be control systems with Are we ready for thisthis delugedeluge ofof logicallogical ANDs,ANDs, ORs, and the capability ofof beingbeing user-programmed,user-programmed, asas wellwell asas NOTs? I I thinkthink not! The idea of a computer in every being able to be connected to the telephone line or home is only valid if the computer can "do something" cable television forfor electronic mailmail transfer,transfer, library without constant help from the owner. perusal, or electronic fund transfers. Then our home computercomputer willwill "do something". informed me theythey are goinggoing toto aa newnew format,format, etc.,etc., etc.,etc., etc., and will bebe available January '79. Very atrocious I believebelieve the home computer manufacturers hadhad betterbetter service — andand theythey provide no information unlessunless you start communicating withwith eacheach other.other. IfIf theythey don't,don't, call and askask themthem forfor it.it. some enterprising telephone or television company may jump into thethe ballball parkpark andand stealsteal thethe ballball —— and Apparat (Denver, CO) — hadhad mymy orderorder forfor six weeks. the game. Two phone callscalls laterlater theythey informed me they were no longer selling PET softwaresoftware andand returnedreturned mymy money. They could call theirtheir new home computer "DIALOGUE", andand justjust copycopy thethe sales literatureliterature from Sawyer Software (tape obtained throughthrough NEECO)NEECO) II Radio Shack,Shack, Commodore,Commodore, or or Apple.Apple. At At $695, $695, every returned one tape of two purchasedpurchased because thethe home should have one. programming was atrocious — andand thethe days-between-days-between- dates program was nono goodgood itit used thethe wrongwrong Enough! II could gogo onon andand on,on, butbut II think you get my algorithm). point. What about my friend Henry? He satsat patientlypatiently while I tried toto explainexplain thethe valuesvalues of a computer in the Commodore (Palo Alto, CA) They lost my order. home. Henry replied that he could do most of the Things beingbeing whatwhat theythey were atat Commodore, II justjust control functions my computer can do, manually and at canceled thethe wholewhole thingthing beforebefore theythey wentwent anyany farther.farther. a considerable savingssavings inin money.money. AsAs aa mattermatter ofof fact, I orderedordered inin MayMay and cancelled inin August. No tapestapes with the money he just saved by not buying a home available atat thatthat time. computer, he is going to buybuy aa microwavemicrowave oven.oven. "You"You Osborne & Associates — ordered the PETPET software know, the one with the digitaldigital clockclock andand 25 ("Some Common BASIC Problems")Problems") at the WestWest Coast programmed functions?" Computer Faire November 3,3, 4, & 5, 1978. ToTo date These areare somesome ofof mymy views.views. II would be very interested (12/19/78) havehave notnot receivedreceived it. ItIt was was supposedsupposed to have in reading aboutabout your views inin thisthis journal. I will not be been shipped "last"last week".week". Looks likelike hishis outfitoutfit is just unduly upset ifif you (or(or no one else,else, for for thatthat matter)matter) like mostmost ofof thethe onesones inin thethe PCPC business,business, despite his agrees withwith me. If you wish to communicate withwith me, I high-brow sounding statements inin hishis FountainheadFountainhead can be reached at:at: editorials inin Interface Age. U.R.A. Dreamer, P.O. Box 911, DisneylandDisneyland We especiallyespecially thankthank DennisDennis for for writingwriting toto tell us about ,A.J. Cote, The Open Channel,Channel, Computer, October his experiences withwith softwaresoftware firms.firms. NotNot wantingwanting to 1978, p.75 spoil his praise, however,however, wewe havehave toto admitadmit thatthat our 2 Gene Beals, PET UserUser Notes,Notes, Issue 6, 1978, p.32 shipping schedule "slipped""slipped" aa weekweek oror soso overover thethe 3Donn Mennie, Personal Computers For The holidays! Sorry. Enterpreneur, Applications.Applications, Spectrum, September, We'd likelike to hear from more of you regarding your 1978, p.32 experiences withwith software — and hardware — dealers.dealers. 4 James Isaak,!seek, Standards ForFor The Personal Computing Who's givinggiving you the kind of service they promise? Network, Computer, October, 1978, p. 60-63 Who isn't? When considering your responses, however, S ANS document X534/589 (ADCCP)(ADCCP) from CBEMA,CBEMA, 18181818 remember that many of usus run ourour businessesbusinesses outout ofof L Street NW, Washington, DC 20036 our homes in our "spare" time — and don'tdon't have eighteight 6 R.B. Hovey, Packet Switching Networks AgreeAgree OnOn hours a day to spend at it. Can you tell the difference Standards Interface,Interface, Data Communications, between the products delivered by a "homebrew" May/June, 1976 pp. 23-39 company and a "professional" firm? What are thesethese differences? How dodo theythey stack up against each other? Which delivers thethe better products for thethe bestbest priceprice inin REVIEW -- SOFTWARESOFTWARE DEALERSDEALERS the least amount of time? by Dennis Costarakis

For Readers whowho mightmight have difficulty usingusing MichaelMichael Dennis Costarakis writes:writes: Just receivedreceived #9#9 — asas usual,usual, Baltay's "CHECK"CHECK CAPACITYCAPACITY OF DIMENSION" very informative. For youryour information,information, youryour outfit,outfit, program on page 8 of issue #9, Dr.Dr. JohnJohn Matarella NEECO, and and Channel Channel Data Data Systems Systems areare thethe only three offers this: "software sales" firmsfirms thatthat have providedprovided promptprompt delivery of their advertisedadvertised products. Here's a listlist of Remember a variable or an array is dimensioned by other dealers I have done business withwith — andand thethe PET asas one more than the numbernumber placed in the DIM results. parantheses — thethe 0th element,element. For example: DIMDIM A(12) sets up 13 possible valuesvalues ofof A;A: thatthat is, A(0) Computer Factory (NY)(NY) —— thethe worstworst ofof all.all. In March, through A(12). 1978. I orderedordered theirtheir annualannual ReportReport Analyzer,Analyzer, Stock Screen, and annual reportreport DATA DATA BASEBASE — (annual Changing Michael's program by startingstarting all all FOR/NEXT FOR/NEXT subscription —— 1 1 tape/month). tape/month). ItIt took six months to loops withwith 00 willwill really show when and wherewhere wrap-wrap- receive a workable Annual Report AnalyzerAnalyzer (at(at least around occurs. twenty phonephone calls). TheThe stock Screen, thoughthough i.e. Lines 170 & 230 N=O: FORFOR TO N1 promised several timestimes asas "next"next month"month" still is not lines 180 & 240 FOR ,N3ITO..N) TO N2N2 available (my feeling is that itit hasn'thasn't beenbeen developeddeveloped yet). TheThe DATADATA BASE doesn'tdoesn't workwork —— II sent back the In mymy PET,PET, ifif (N1+1)*(N2+1)(N1+1)*(N24-1) 255, then wrap-aroundwrap-around only two tapes I received.received. TwoTwo weeks ago they Occurs.occurs. A DECODER ADD-ON TO THE the location 1023.1023. Then settingsetting S9=PEEK(1023) produces the desired value. MEM-EXPLORER Now that thethe necessarynecessary tools are available,available, we can by RoyRoy Busdiecker discuss thethe problemproblem ofof turning tokens into their equivalent reserved words. Because of the identicalidentical In thethe previousprevious article,article, "The"The PETPET SymbolSymbol Table and sequences, wewe can simply subtractsubtract 127127 from the value Data Formats", there was a description ofof aa program of the token to determine whether we need the first, called MEM-EXPLOREFle.MEM-EXPLORERe. That program allowsallows second, or nth reserved word. examination of a block of 20 bytesbytes ofof memorymemory specifiedspecified If wewe countcount thethe numbernumber ofof characterscharacters inin eacheach reservedreserved by the user.user. AA displaydisplay is provided, showing the locationlocation word, and storestore those values in the same sequencesequence in address, contents in both decimal and character any array, we can then use that array to createcreate a equivalent, and severalseveral usefuluseful computations.computations. pointer to the beginning of each reserved wordword in the Since special reservedreserved wordswords used used by by the the PETPET (e.g., (e.g., ROM. For example, if the token value is 131,131, then we RUN, GOTO,GOTO. LOG)LOG) areare storedstored asas single-bytesingle-byte tokenstokens want to find the 131 — 127, or 4th wordword in the table. rather thanthan asas charactercharacter strings,strings, thethe MEM-EXPLORERMEM-EXPLORER Summing thethe firstfirst 3 3 valuesvalues in in the the array array gives gives 3+3+4=10, 3+3+4=10, only provides thethe character equivalent of the token. which is addedadded toto thethe tabletable startingstarting valuevalue ofof 49298.49298. One must then go to a table to determine the reserved word it represents. STARTING Except for that shortcoming,shortcoming, it isis possible to read a LOCATION CONTENTS program (vertically, inin thethe CHARCHAR column)column) fromfrom itsits 49298 ENDENO absolute location in memory, and knowknow preciselyprecisely where 49301 FOR every character is locate-d.located. IfIf we could decode each 49304 NEXT token and print the reservedreserved word in its place in the 49306 DATA CHAR column,column. it would be handy indeed! 49312 INPUT#INPUTO Fortunately, the designers of the interpreter tuckedtucked 49318 INPUT away the completecomplete expandedexpanded formform ofof eacheach instructioninstruction 49323 DIM in ROM, starting at locationlocation 49298. SeeSee thethe TABLETABLE forfor locations ofof thethe expandedexpanded forms. The sequence in which the reserved wordswords are storedstored isis identicalidentical toto thethe The next value in the array, 4. tellstells how many sequence of numerical values for the tokenstokens usedused to characters needneed toto be taken from the table to completecomplete represent them_ the expanded form of the word.word. TheThe fourfour characterscharacters starting at location 4930849308 are D, A,A, T,T, A,A, andand DATA DATA isis Unfortunately, thethe interpreterinterpreter prevents prevents PEEK PEEK accessaccess to the reserved word that token 131 isis used to represent. the ROM area where the interpreterinterpreter is stored. TheThe command PRINT CHR$(PEEK(49298)), which ought to Lines 11001100 — 1150 create the arrayarray A%A% whichwhich holdsholds the print the charactercharacter "E","E', actually "prints""prints" aa nullnull onon thethe lengths of the reservedreserved words.words. screen (no character or space),space), incorrectlyincorrectly implying The pointer (PT) is calculated inin lineslines 183 183 -- 185.185. that thethe addressaddress specifiedspecified contains all zeros in binary.binary, Finally, to complete thethe example by printing outout thethe Fortunately, in a previous encounter with this expanded form of the reserved word,word, we add the restriction onon the PEEK command,command, thethe author equivalent of developed a simple machine-language program to defeat it. All that was needed was an LDA (load(load FOR 1=11=1 tolo A%(4):PRINT CHR7(PEEK(49297+PTCHFICPEEK(49297+PT4-R));:NEXT- 1));NEXT I accumulator) from anan addressaddress inin thethe "forbidden"forbidden except that we mustmust makemake thethe previously previously describeddescribed region", followed by an STA (stored accumulator) to an substitution forfor thethe underlined statementstatement in order to address where the PEEKPEEK could be used. An FITS PEEK intointo thethe "forbidden region".region'. The equivalentequivalent codecode (return fromfrom subroutine)subroutine) givesgives controlcontrol backback toto BASIC.BASIC. appears in lines 186186 —— 188188 of the program. In thethe programprogram listed atat the end of the article, lineline 10001000 Putting all these tools together,together. and weaving them intointo sets the pointer from the USRUSR function, and loads the the MEM-EXPLORERMEM-EXPLORER described previously, yieldsyields thethe data from line 1020 intointo thethe bufferbuffer areaarea for for the the second second new program listed atat the end of the article. If youyou have cassette recorder. ThatThat data is the machine language already typed in the MEM-EXPLORER,MEM-EXPLORER, loadload itit inin thethe routine described above. PET, then type in the lines which are new or changed. To see how the routine is used, looklook atat lineline 150150 ofof the When this program is run,run, It willwill ask LOCATION? IfIf program. In thethe previousprevious article, it waswas you answer 1025, then thethe firstfirst 20 bytesbytes of thethe programprogram will be displayed. The first two bytes contain a LINK 150 M=PEEK(L)M=PEEK(L) ADDRESS pointingpointing toto the beginning of the secondsecond lineline which has now being replaced by of the program. TheThe numericalnumerical value of the LINKLINK ADDRESS isis shownshown underunder the ADDRESS heading, in 150 SL:GOSUBSL:GOSUB 2000:M=S92000:M=S9 the first line displayed. TheThe numerical value of the The subroutine at line 2000 convertsconverts the value in S9 to BASIC program line number assigned by the two bytesbytes which are poked into the machine language programmer to the firstfirst lineline ofof hishis program isis contained routine as the address for the LDA (load accumulator) in the third andand fourthfourth bytesbytes (1027, (1027, 1028)1028) of that command. The thethe USRUSR functionfunction isis called,called, whichwhich program. It isis shownshown in the thirdthird lineline of thethe display.display. places a copy of the contents of the target addressaddress in Subsequent lines showshow thethe actualactual representationrepresentation ofof thethe

TABLE BASIC program statements as theythey areare storedstored inin LOCATION CONTENTS memory, under the CHAR column. A value of 0 signals Decimal Hex the end of a line of BASIC CODE, and always precedes Decimal the next LINK ADDRESS byte-pair. A LINK ADDRESS 49298 C092 ENDFORNEXTDATAINPUT#INPUT low value of 0 indicates the end of a BASIC program.program. 49323 COAB DIMREADLETGOTOFUNIFRESTORE 49349 C005 GOSUBRETURNREMSTOPONWAIT 49373 CODD LOADSAVEVERIFYDEFPOKEPRINT# 49400 COF8 PRINTCONTLISTCLRCMDSYSOPEN 49426 C112 CLOSEGETNEWTAB(TOFNSPC)THEN 49453 C12D NOTSTEP+-*/tNOTSTEP+-•/t ANDOR = SGNINT 49479 C147 ABSUSRFREPOSSQRRNDLOGEXPCOSABSUSRFREPOSSORRNDLOGEXPCOS 49506 C162 SINTANATNPEEKLENSTR$VALASCS1NTANATNPEEKLENSTR$VALASC 49532 C17C CHR$LEFT$RIGHT$M$D$@CHR$LEFT$RIGHT$M1D$@

MEM-EXPLORER/DECODER

80 IF E1=1 THEN 110 90 GOSUB 1000:GOSUB 1100:E1=1 '• 100 B=256:POKE 59500,1459500.14 • 110 INPUT"LOCATION";K '• 120 PRINT"1LOCAT'NPRINT"1LOCAT'N DECIMAL DECIMAL CHAR CHAR ADDRESS ADDRESS VALUEI"VALUEI" ' 130 FOR TO 19 • 140 LA(+J 150 S9=L:GOSUB 2000:M=S9 •' 160 PRINT L; •' 170 PRINT TAB(8);M; 180 PRINT TAB(18)::IF M<32 THEN 195 181 IF M4 THEN PRINT CHR$(34);CHRS(20);CHR;(34);CHRS(20): 182 IF M<128 OR M)202 THEN 190 183 PT41:ID4A-127:FORPT41:1D4A-127:FOR 1=1 TO ID-1 184 1P71l--,7T+A%(1)-+A%(1)

vow%Mr 185 NEXT I 186 FOR 1=1 TO A%(ID) 187 S9S9=49297-:-.49297 + + PT4-1:GOSUB PT-H:GOSUB 2000:IF S9)127S9)127 THENTHEN S9=S9-128S9'S9-128 188 PRINT CHRS(S9);:NEXT 1 189 GOTOGOTO 195 195 • 190 PRINT CHRS(M);CHR$(M), 195 S9A_+1:GOSUB 2000 200 PRINT TAB(25);M-1-9*S9;TAB(25);M+B*S9; 210 PRINT TAB(32);B*M+S9 '• 220 NEXT J • 230 PRINT 240 GOTOGOTO 80 80 1000 POKE 59500,1:X:POKE59500.1:X:POKE 1,58:POKE 2,3 :A4126:FOR I=A TO A+6:READ C:POKE I,C:NEXT I 1010 RETURN 1020 DATA 173,0,192,141,255,3,96 1100 DIM A%(75) 1110 FOR 1=1 TO 75:READ A%(I):NEXT I 1120 RETURN 1130 DATA 3,3,4,4,6,5,3,4,3,4,3,2,7,5,6,3,4,2,4,4,4, 6,3,4,6,5,4,4,3,3,36,3,4,6,5,4,4,3,3.3 1140 DATA 4,5,3,3,4,2,2,4,4,3,4,1,1,1,1,1,3,2.1,1,1, 3,3,3,3,3,3,3,33,3,3,3.3,3,3,3 1150 DATA 3,3,3,3,3,3,4,3,4,3,3,4,5,6,43.3,3,3,3,3,4.3,4,3,3,4,5,6,4 2000 D%=S9/256:E-S9-D%'256:POKED%=S9/256:E=S9-D%•256:POKE 827,E:POKE 828,D%: Y=USR(0):S9=PEEK(1023):RETURN NOTE: ' marks lines which are unchanged from original MEM-EXPLORER.

Entire article and program copyright October 29, 1978 by Roy Busdiecker, Woodbridge, VA 22193. FAST-FORWARD TO FIND YOUR PROGRAM by Robert Buxton

Who wants to search through 30 minutes ofof tapetape 540 IF T1$ R$ GOTO 540 looking for a program? A dumb tape counter onon thethe 550 POKE 519,52:POKE 59411,61 PET would have been worth the front-end money! 600 PRINT"/CDDDDDRRRRRRRRRRRRRRRRRRR/PRE Without getting into more obvious and expensive ESS /F/STOP/O/"/F/STOP/Or hardware-type solutions, I have a program that has 610 IF PEEK(519) 0 GOTO 610 worked for me — and will work equally well for you. 620 PRINT "/CDDDDDRRRRRRRRRR/HIT /F/RETUR/F/RETUR The DIRECTORY merely fast-forwards the cassette N/O/ & IF/PLAY/O/"/F/PLAY/O/" until just before the program of interest, then stops. 630 PRINT "/RRRRRRRRRRRRRRRR/"; This enables you to load just the desired program. By 640 FOR 1=1 TO 7:PRINT"/-0/-=/DLLL/"::NEXT7:PRINT"/-0/-=/DLLL/";:NEXT II accurately controlling thethe F.F. FWDFWD capability of the 650 PRINT "1-"/- t-/--/UUUUUUUU/"(-/—/UUUUUUUU/" cassette recorder, any program on a 60 minute cassette 660 FOR 1=1 TO 25: PRINT "/R/";:NEXT I can be loaded correctly within two minutes instead of 670 FOR 1=1 TO 10: PRINT "/-]/RLJ";:NEXT"/-]/RL/";:NEXT II in as many as 30 minutes. 680 PRINT "/---/LL/": 690 FOR 1=1 TOTO 3:3: PRINTPRINT "/-@/RLJ";:NEXT"/-@/RL/";:NEXT I The program needs to be "educated" with the details of 700 PRINT "/-"/- (-/"-/" your particular cassette. Lines 40-90 of my example 710 PRINT "/UUU/LOAD/UUU/" program shows 12 programs and their load points. The load point is the number of integer seconds that itit takes your transport to fast-forwardfast-forward fromfrom thethe endend ofof thethe Graphics used: DIRECTORY program (located at the beginning of the tape) to just prior to the desired program.program. II havehave foundfound IC//C/ clear clear screen screen Line 640 E 1 1 /-0/ /-=/ that integer seconds provide adequate resolution to do /0/ID/ cursor cursor down down this task. If further resolution isis desired,desired, oneone mightmight /U/ cursor cursor upup Line 650 I- wade into the jiffy clock, but I believe that the pi /R/ cursor cursor right right uncertainty of the F. FWD capability overshadows thisthis /U/L/ cursor cursor leftleft Line 670 670 IL resolution. Be sure to enter your load point time as a six-digit, /-0/=shift zero Line 680680 Fri right-justified string, in order toto interfaceinterface withwith thethe PETPET /=/=shift equals T1$TI$ internalinternal clock.clock. /-I- 4-/-shift left arrow Line 690 690 E /-)/=shift/-]/=shift right bracket

10 REM DIRECTORY /-@/=shift "at" Line 700 20 REM Program name 30 INPUT "/C/FILE NAME";A$ and load point 35 REM Tyson Richmond writes: II waswas toldtold thatthat leavingleaving mymy PETPET 40 DATA "POLE", "000003", on continuously, as long as the screen was off, "NF&IP", "000006" wouldn't hurt it. Now it won't SAVE programs, although 50 DATA "SENSITIVITY", "000008", it LOADs fine. Any suggestions? TheThe answeranswer isis "Only"Only "SPUR" "000012" one suggestion — it sounds like cassette problemsproblems —— 60 DATA "CURVE FIT", "000015", probably not caused by leaving the PETPET turned on. All "#CONVERTER", "000018" you can do is return the cassette unit (or the PET) to 70 DATA "AMORTIZATION", "000020", Commodore for repair. "FFT", "000025" 80 DATA "AFILT", "000029", "MATRIX INVERSION", "000033" MOEBIUS STRIP CASSETTES 90 DATA "MATRIX MULT", "000036"."000036", FOR PET? "FILT", "000037" 100 DATA "END", "END" John Hirsch writes: I recently got the brilliant idea (?) of using one of those endlessly repeating cassettescassettes 105 REM (with a moebius strip foldover) toto recordrecord datadata files.files. TheThe 107 REM files could then be located and searched under 110 READ B$,R$:IF B$="END" THEN RESTORE program control without rewinding — giving very slow :GOTO 10 but sure access to any field. With the files loaded, I 120 IF AS=B$A$=B$ GOTO 500 then ran my program and got an "?"? ILLEGALILLEGAL 130 GOTO 110 QUANTITY ERROR" after a certain point. The READY 500 PRINT "/CDDDDDRRRRRARRR/PRESS"/CDDDDDRRRRRRRRR/PRESS IF/STOP/F/STOP message which followed was REDYREDY —— withoutwithout thethe "A"."A". /0/ THEN /F/F,/F/F, FWD/O/"FWD/Or I assume this problem occurred when the tape looped 510 IF PEEK (59411) 53 GOTO 510 back. Does anyone have an explanation? Without one, 520 T 1$="000000" I'm up the creek without aa (CH(CH CK)CK) PP DDLE!DDLE! 530 POKE 519,52:POKE 59411,53 sensationalsonsatioRal software CS-1005. Graphics Games-2.Genres-2. Six favoritefavorite Why shouldshould youyou selectselect PET (8K) (8K) SoftwareSoftware games. LEM, lunar lender withwith a graphic Creative Computing display andand optionaloptional auto-pilot. auto-pilot. Nuclear CS-1001. Logic Games-1. Six favorites ffrom rom Reaction, a game ofof skill for two players. Software? BASIC ComputerComputer Games Games with super Artillery, in which twotwo playersplayers shootshoot itit out graphics. Awed, the African logic gamegame withwith over computer-generated terrain. terrain. Bounce 1 Highest quality programs-outstand- 12 pits andand 3636 beans.beans. Bagels, which traces the path of a ball bouncing around ing applications for education, recrea- challenges youyou toto guess aa secretsecret 3-digit3-digit the screen. Checkers, with graphic display, tion, business,business, and household manage- number. Martin Gardner's Chomp in which from our BASIC Games book. Dodgem, try ment. you chomp on a cookie with a poison to outmaneuver another player oror the 2. Best value-upvalue-up to to ten different pro- corner Flip-Flop-change a row of X's to computer to getget youryour piecespieces across the grams per tape. 0'sO's Hexapawn played with three chesschess board first.first. $7.95. 3 Reliability-programs thoroughlythoroughly test- pawns. Hi-O,HI-O, a solitaire peg-removal game. ed and de-bugged •• $7.95$7.95. CS-1006. Conversational Games-1.Games-1. Talk to 4. Redundant recording- two copies of ELIZA, thethe computerizedcomputerized psychoanalysis every orogramprogram on each tape. CS-1002. Number Games-1. SixSix numbernumber program. Compose poetry poetry with with Haiku. 5 Professional qualityquality tape-hightape-high density logic games includingincluding Guess in which you Challenge youryour vocabulary and word- oxide, 100% calendered, flat frequency guess a secret number.number, 23-Matches-try not guessing skillsskills with Hangman. Hurtle, try to response, lowlow noise,noise, highhigh output to take thethe lastlast matchmatch Letter in which you find the hurkle on the 10 by 10 grid in five 6. Anti-jam cassette-tefloncassette-teflon lubricated guess aa secret secret letter. letter Number, a random moves. In Hexletter, you compete to capture six-rib gasket, hardhard weldedwelded windows. jackpot gamegame Trap in which youyou traptrap aa more letters on a hexagon than your oppo- double locking self lubricating hub, mystery number between two trap numbers. nent. $7.95.$ 7 .95, double flanged rollers on stainless steel Stars gives you stars as clues to the secret pins, heavy metal shield number $7 95 Blank CassettesCassettes 7. Hard plastic box-best protection, easy to file. CS-1201. Sensational Simulations-1. Simulations-1. Five CT-C8. Blank C-8 cassettes with 4 minutes 8. Widely available-carried by most retail super simulations including the popular of tape per side. Perfect for one or two computer stores Animal inin which which thethe computercomputer learns programs. Highest quality tape packaged in 9. Made in U S.A. animals fromfrom youyou Fur Trader lets you trade nifty redred translucenttranslucent cassettescassettes in soft plasticplastic 10 Inexpensive-best value per dollar of furs in old Canada. Hammurabi in which box. $1.00 ea., 5 for $4.00 . any software. you manage thethe city-statecity-state of Sumeria.Sumena. OrOr trytry Co making your fortune in the Stock Market.Markel. A Computermputer Music logic game,game, Word, has you guess secret Sampler Books words:words. $7.95. CM-101. Computer Music Sampler. A stereo 6C. BasicBasic ComputerComputer Games:Games: Microcom- CS-1003. Logic Games-2.Games-2. Six challenging audio cassette containing a full hour of puter Edition.Edition. Edited by David Ahl, this puzzles including including Rotate, in which you computer music played on four different major revisionrevision of of 101 Basic Computer order a matrixmatrix ofof randomrandom letters letters Strike-9, Strike-9, synthesizers (Solid State Music.Music, ALFALF Games is our bestbest seller.seller. AllAll thethe classicsclassics areare try to remove all nine digits without striking Products, Software Technology, and Don here Super Star Trek, Football, Blackjack, out. The classic number number game, game, NIM. In Schertz' home brew). Also two speech Lunar Lander, Tic Tac Toe, Nim, Life, and Even-Wins try toto taketake anan eveneven number of synthesizers (Computalker(Computalker andand the1 he original original Horserace. LotsLots ofof sportssports simulations: chips. Hi-Lo, a number guessing game with 1963 Bell Labs synthesizersynthesizer singingsinging "Daisy'')"Daisy") Basketball, Bowling, Boxing, Golf, Hockey a jackpot.jackpot. Batnum, the super "battle of C-60 cassette in soft plasticplastic box,box, $5.00. and Darts. Casino games:games. Craps, Poker,Poker, numbers" $7 95 Roulette and Slots. Total of 102 games all in Software Authors Microsoft Basic withwith large, legible listings. CS-1004. Graphics Games-1.Games-1. Five amazing 200 pp softbound, $7.50. realtime graphicsgraphics gamesgames designeddesigned especial- Creative Computing is seeking superior ly for your PET. In In Chase,Chase, one player software to broaden our line. WeWe pay 9F. Basic andand thethe Personal Computer.Computer. By pursues the other through a maze of authors a 10%10% royalty on the retail list price. Thomas Dwyer and Margot Critchfield. One obstacles and and "zap "zap doors." doors." Escape- Send your cassette withwith documentation toto of thethe best best and and most most comprehensive comprehensive attempt to escapeescape from a prison patrolled by us with three 156156 stampsstamps forfor return.return. Please Please presentations of Basic with examples robot guards. Dart provides arithmetic drill allow 8 weeks for evaluation. specifically developed for personal corn-com- and indicates how close your response isis toto puters. LotsLots on graphics,graphics, games,games, datadata basesbases the correct answer onon aa dartdart board. In To Order... and much more 350 pp $12.95. Snoopy you compute distances on a Creative Computing Software should be number-line while trying toto shootshoot downdown thethe stocked byby youryour local retailretail computer store.store. 7E. Basic Programming.Programming. By Kemeny and Red Baron.Baron. InIn Sweep you must try to hit ninenine If youryour favoritefavorite outlet doesn't yetyet offeroffer it,it, Kurtz this book was termed by aa reviewerreviewer asas targets in order by controlling the path of a have him call C.J atat 800-631-8112.800-631-8112. (In NJ,NJ, "the bestbest text onon BasicBasic on almost all counts " cannonball $7.95. 201-540-0445) An excellent, gradual introductionintroduction to Or you can order directly from Creative programming in Basic withwith lots of ex- Computing. Send your check for tapes plus amples. 150150 pp.pp. softbound.softbound. $8.50.$8.50. $1 00 shipping and handling per order to 7M. Some Common Basic Programs.Programs. By creative Creative Computing Software, P.O.P.O. Box Adam Osborne. An idealideal workbookworkbook for use 789-M, Morristown. NJNJ 07960. NJNJ residents in a Basic programmingprogramming course oror for self add 5% sales tax VisaVisa or Master Charge are ...,study. Contains 76 general purpose, prac- computing acceptable also. For faster service, call in tical Basic programsprograms withwith complete listings. your bankbank cardcard orderorder tolltoll freefree toto 800-631- 192 pp. softboundsoftbound $7.50.$7.50, software 8112. (In NJ, 201-540-0445).201-540-0445). BASIC IN ROMROM by Robert H. Wind

These tables list the addresses where the BASIC routines reside. The addresses are stored as pairs ofof bytesbytes (low-order byte first, then high-order byte) inin twotwo tablestables atat ROMROM locationslocations 4915249152 thruthru 4922149221 andand 4922249222 thru thru 49267. 49267. The first table lists the routine address minus one, and the second table lists thethe routineroutine addressaddress exactly.exactly. II believebelieve the list is accurate, but I haven't thoroughlythoroughly checkedchecked outout allall thethe routines.routines. II inviteinvite corrections,corrections, extensions,extensions, andand comments. My phone is (313) 694-1699, and my address is 4092 Knollwood Drive, Grand Blanc, MI 48439.

TABLE 1 TABLE 2

ROUTINE ADDRESS BASIC ROUTINE ADDRESS BASIC HEX DECIMAL COMMAND HEX DECIMAL COMMAND

C551 50513 NEW 0000 0 USR

C5A8 50600 LIST D264 53860 FRE

C649 50761 FOR D285 53893 POS

C7OD 50957 RESTORE D349 54089 STR$

C71C 50972 STOP D5C4 54724 CHR$

C71E 50974 END D5D8D5 D8 54744 LEFT$

C745 51013 CONT D604 54788 RIGHT$R1GHT$

C770 51056 CUR D6OF 54799 MID$

C775 51061 RUN D654 54868 LEN 54868 C780 51072 GOSUB D663 54883 ASC 54883 C79D 51101 GOTO D685 54917 VAL

C7CA 51146 RETURN D6E6 55014 PEEK

C7F0 51184 DATA DBBF 55487 LOG 55487 C920 51232 IF DBOB 56077 SGN

C833 51251 REM DB2A 56106 ABS

C843 51267 ON DB9E 56222 INT

C89D 51357 LET DE24D E24 56868 SOR&OR

C97F 51583 PRINT# DEAODEAD 56992 EXP

51589 CMD RND C985 DF45 57157 RND C99F 51615 PRINT DF9E 57246 COS C99F 57246 CA9F 51871 GET DFA5D FA5 57253 SIN

CAC6 51910 INPUT# DFEE 57326 TAN

CAEO 51936 INPUT E048 57416 ATN

CB24 52004 READ Note: In my PET, these addresses 52278 NEXT CC36C C36 appear to be 00 when PEEKed. CF71 53105 DIM CF71 However, by transferring these DEF D295 53909 locations to RAM with a machine language program, thethe locationlocation 55033 POKE D6F9 in RAM can be PEEKed to observe WAIT D702 55042 these tables. FFCO 65472 OPEN Robert H. Wind 65475 FFC3 CLOSE FFD5 65493 LOAD LOAD FFD8 65496 SAVE George Risk Industries.Industries, GRI Plaza, Kimball, NE 69145 FFDB 65499 VERIFY announces PERK — the Professional Encoded Remote FFDE 65502 SYS Keyboard — for PET. Its a plug-in, typewriter style, alphanumeric keyboard, sharing the PET's internal keyboard interface with the PET's own keyboard — making both boards fully active and useable. No soldering or assembly required, no charges or modifications are needed, and a plug-in, UL listed power supply is provided. Standard CRT terminal Ed Steinfeld asks if the CmC IEEE/RS232 interface is control functions are implemented for cursor control, truly a bidirectional interface — and can he connect more than one keyboard at aa timetime maymay be attached to any RS232 device to it and use the terminal for data the PET, and full screen editing capabilities are entry & output? Unfortunately, the answer isis NoNo —— it'sit's provided. Custom steel desktop enclosure, plug-in not a true bidirectional interface. Its RS232 is output interface card, power supply, full instructions,instructions, handyhandy only." reference card, and 90-day warrantywarranty areare allall includedincluded (along with the keyboard itself!) for $229 — wired andand tested. Write to Robert Nichols for moremore details.details. You lovelove youryour PET,PET, but wouldn'twouldn't youyou love itit moremore withwith thisthis BigKeyboard? BigKeyboard?

ma: la& as. am • WS dllb

The SkylesSkyles Big Big KeyBoarem. KeyBoard (TM).More Morethan 15 than inches 15 wide.inches A wide.layout A nearly layout nearly identical to to the the PET PET Keyboard Keyboard and with and allwith functions—alpha, numeric. numeric. graphics, special special symbols, symbols, lower lower case alpha—on case alpha full-sized, —on full-sized, almost plump, almost plump,S key-tops double-shot double-shot to guarantee to guarantee lifetime lifetime durability. durability. Actual size size The switchingswitching action action uses uses gold crossgold pointcross contacts; point contacts; the torsion thesprings torsion are gold-plated. springs are gold-plated. The housinghousing is blackis black anodyzed anodyzed heavy heavyaluminum, aluminum, The keyboard The keyboardassembly and assembly housing have and housing have drain-holes; to toclean clean the keysthe keysof "gook," of "gook," rinse under rinse clear under water clear and letwater dry. and let dry. Parallel entryentry andand unbelievablyunbelievably easyeasy toto install. Connect the the PET's PET's keyboard keyboard cable cableto the to the Skyles Big Big KeyBoard. KeyBoard. Connect Connect the Skyles the Skyles cable connector cable connector to the main to board the mainand to boardthe and to the Skyles Big Big KeyBoard KeyBoard housing. housing. Now Nowyou can you use can the useSkyles the for Skyles fast, finger-easy for fast, datafinger-easy entry. data entry. the original original PET PET Keyboard Keyboard for hunt-and•peckfor hunt-and•peck graphics graphics entry. And entry. you can And disconnect you can disconnect either keyboard—or keyboard—or both—without both—without reopening reopening your PET: your just PET: remove just the remove connector(s) the connector(s) n11, from the the Skyles Skyles housing. housing. Fully guaranteed, of course:course: • Use• Use it for it forten tendays. days. If you If don't you like don't it for like any it reason,for any reason, return it it for for full full refund; refund; no questionsno questions asked •asked Guaranteed • Guaranteed for 120 days; for we'll 120 repairdays; or we'll repair or replace at at no no charge charge if the if Bigthe KeyBoard Big KeyBoard proves provesdefective defective for any reason for any short reason of short of malicious mischief. mischief. Order the the Skyles Skyles Big Big KeyBoard KeyBoard now. now,Enjoy Enjoy it within it weeks.within We'llweeks. ship We'll it by shipair it by air and prepay prepay all all shipping shipping and handlingand handling on orders on placed orders with placed the enclosed with the coupon. enclosed coupon. (And seesee thethe otherother sideside ofof thisthis pagepage forfor informationinformation onon thethe SkylesSkyles Memory Memory Expansion Systems.Systems.) )

q I'd likelike to to purchase purchase these these Skyles Skyles products products now. I understandnow. that that I may return return any any Skyles product product within within ten daysten daysfor immediate for immediate and complete and complete refund. refund. 8KB 8K Memory Expansion System(s) at $250:$250: (15,359 bytes free:free: $ Adds 8,192 bytes to the 7,1677.167 bytesbytes residentresident inin youryour PET)PET) 16KB 16K Memory Expansion System(s)System(s) at $450:$450: (23,551 bytes free.free: $ 4O dds 16,384 bytes to the 7,1677,167 bytesbytes resident)resident) 24KB 24K Memory Expansion System(s)System(s) atat $650:$650: (31,743 bytes free:free: $ Adds 24,57624,576 bytesbytes toto thethe 7,1677,167 bytesbytes resident) resident) 74KB Big KeyBoard(s) at $125:$125: Orders placed now (see other side for ordering information) will be shipped by air prepaid: Skyles will absorb all shipping & handling costs. TOTAL SS P. COMMERCIAL AGENTSAGENTS FOR 599 N.N. MathildaMathilda Ave., Ave., Suite Suite 26 Skyles Electric WorksWorks Sunnyvale, California California 94086 (OVER) Would youyou likelike to turnturn onon youryour PETPET . . .. andand see this 4 You could and right now, ifif you had the Skyles 24KB24KB MemoryMemory ExpansionExpansion System ... oror you could have 23,551 bytes free with the 16KBI6KB SystemSystem ... or 15,359 bytes freefree withwith thethe 8KB.8KB.

Skyles Memory Expansion Systems are complete; nothing moremore toto buy.buy. •• FirstFirst qualityquality static RAMsRAMs •• Solid solderedsoldered onon first quality glassglass epoxy epoxy board board •• SeparateSeparate PETPET AdapterAdapter Printed Circuit BoardBoard connectsconnects directlydirectly to to data data bus bus on on your your PET—no PET—no rat'srat's nestnest ofof hang-hang- ing hand-wiringhand-wiring •• RibbonRibbon cablecable and and 50 50 pin pin connectors connectors that that keep keep your your PET PET open open toto thethe outside world (one onon the 8KB; two on the 16KB16KB and 24KB).24KB).

Skyles Memory Systems install in minutes with no special tools or equipment ...... other than an ordinary screwdriver. From BobBob Skyles,Skyles, formerly Chief Engineer for several personal computer companies and instrumental in making the PET aa deliverable, off-the- shelf reality.reality. All Skyles products are double guaranteed: If not completelycompletely satisfied, return itit withinwithin ten days for a full refund. And if the SkylesSkyles productproduct should proveprove defectivedefective for anyany reason—short ofof maliciousmalicious mischief—withinmischief—within 120120 days,days, we'll replacereplace oror repairrepair atat nono charge. Order nownow forfor guaranteedguaranteed deliverydelivery within four weeks;weeks; we'll shipship your order by air and prepay all shippingshipping andand handlinghandling onon ordersorders placedplaced now.now. So use the handy coupon to order.order. (Please(Please fill inin bothboth sides.) ===== •••••••••• n •• nnn ••1======•••• nn •• ■n ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■■ ••=. For the Skyles products indicated on the other side ofof thisthis coupon,coupon, q❑ I enclose mymy checkcheck oror moneymoney order forfor $ *California residents: Please add 6% sales tax;tax; SantaSanta ClaraClara County.County. California: 6.5% tax. q❑ I'd like you to charge the total to:to: q❑ BankAmericard/VISA Account # ❑q Master Charge Expires NAME ADDRESS

SIGNATURE q❑ I'd likelike furtherfurther information; information; please please keep keep me me on youron your mailing mailing list. list. And pleaseplease let let me me know know the the name name of the of nearestthe nearest dealer. dealer. (OVER) • SOFTWARE

DATA RETRIEVAL $10.00 SPACE FIGHT $10.00 Create unlimited numbers of data files of unlimited A two player game in which each player tries to destroy length. EachEach recordrecord inin eacheach filefile consistsconsists ofof upup toto 256256 the other player'splayer's spacecraft byby firingfiring bursts of energy. characters inin as manymany fieldsfields asas required;required; thethe firstfirst three If aa playerplayer firesfires —— andand missesmisses — he's in danger of fields are keyed for selection and sorting purposes. UpUp running in to hishis ownown energy burst andand destroying to 50 records atat a time from any combination ofof himself instead! Written instructions. existing data files can be selected and sortedsorted inin either CHASE $10.00 ascending oror descending order.order. Listing provided. Eight A real-time version of the popularpopular ChaseChase game, in pages ofof documentation. which the robot guardsguards can be as intelligent or asas DATA EDITEDIT $10.00 dumb as the user wishes. Try to escape!escape! Companion program to to our our DATA DATA RETRIEVAL RETRIEVAL MICROMAZE $7.95 program. Edit records, create a new file,file. add to existing A maze isis drawndrawn randomly on the screen —— youryour jobjob is file from the keyboardkeyboard or from another file. Listing to find your wayway out inin thethe shortestshortest possiblepossible time!time! No provided. UsesUses same documentation asas DATADATA two mazesmazes alike. Documented sound is available. RETRIEVAL . BLACKJACK $10.00 STAT I I $20.00 Excellent graphic game. Displays the cardscards asas they areare A real statistical package for up to 100 data points. turned up,up, keepskeeps track ofof youryour winningswinnings (and(and losses),losses), Basic stats,stets, linear regression, moving averages, and wises offof whenwhen you lose. It's the bestbest version of plotting, andand transformation. Listing provided . Blackjack we've seen. No instructions, sincesince ailall Documentation. instructions are incorporated intointo the program itself. STAT II II $20.00 BLOCKADE $10.00 Seven programs inin one packagepackage toto carrycarry outout most of A two-person game in which each player tries to avoid the statistical tests youyou mightmight need.need. AllAll thethe programsprograms the other while also avoidingavoiding thethe wallwall aroundaround theirtheir are interactive and conversational: enclosure. Excellent graphics. Documentation. a. Descstats takes a set of data, eithereither asas singlesingle values or as grouped data, and calculates descriptive statisticsstatistics DEFLECTION $10.00 ... means.means, variance, standard deviation, maximum and A fast-paced, actionaction gamegame inin whichwhich you you attempt attempt toto hithit minimum values. all the targets. TheThe ball movesmoves horizontally andand b. Probf accepts testtest statistics produced fromfrom statistical vertically until itit runsruns intointo aa deflectiondeflection shieldshield youyou placeplace tests: thethe variancevariance ratio.ratio, F,F, Student'sStudent's t, standardizedstandardized on the screen using the M and N key graphics. Timed normal deviate or chi square ... andand calculatescalculates the success toto encourage greatergreater skills. probability of such a value. It replacesreplaces looking up the HOSTAGE $7.95 values in tables, and is also used as a subroutine in all A group of terrorists havehave seizedseized aa planeloadplaneload of the programs below. innocent people. holding them as hostages untiluntil their c.c, /wayanova performs analysis of variance on two or demands are met. You, as governorgovernor ofof thethe realm, are more sets of data, eacheach set being the responsesresponses of a supposed toto do something! ButBut what?what? YourYour chanceschances of group of cases toto aa treatmenttreatment (for example, two drugs re-election depend onon youryour abilityability to make the correct and a control — threethree treatments).treatments). The number of decision inin time. Non-graphic. cases forfor eacheach treatmenttreatment maymay bebe thethe samesame oror different.different. In thethe specialspecial case ofof twotwo treatments,treatments, it isis identicalidentical withwith STARTREKSTARIREK 2001 2001 $10.00 the well-known T-test. America's favorite computer game is available with d. 2wayanova is similar to lwayanova,1wayanova, but but each each casecase isis sound! It usesuses thethe soundsound circuit describeddescribed in issue #1, subjected to two treatments AA and B simultaneously. Volume 1 of THE PAPER. And, And, even even without without sound, sound, it'sits For example, treatmenttreatment A might be different drugs (or a fun game. Search through the galaxies for Klingons, different dosagesdosages of the same drug) and treatment BB refuel your ship at the starbases,starbases, and trytry to avoidavoid being different diets; alternatively, the treatment B can be destroyed by the enemy. Documentation. blocks of a block design. AIR - SEA WARWAR $7.95 e. Anova2wayr is the same as 2wayanova,2wayanova, butbut there are Your navalnaval fleetfleet isis atat war with enemy aircraft! Will you two or moremore casescases (replicates) for each treatment destroy them before they sink your entire fleet? Good combination. AllAll thethe analysesanalyses of variancevariance programsprograms graphics. including tests ofof significance.significance. f. Sfr calculates linear regression, correlation XMON $15.00 coefficients, and coefficients of determination and tests Machine languagelanguage monitormonitor and disassembler withwith an the significancesignificance of all statistics.statistics. DesignedDesigned forfor groupedgrouped exciting difference. The user is actually encouraged toto data, i.e., severalseveral values of Y (the(the dependent variable)variable) make use of the program. AA "menu'' isis displayeddisplayed after for each valuevalue ofof XX (the the independentindependent variable).variable). each command is executed, so you don't have to g. Xyslr is similar to Slr,Slr, butbut thethe XX andand YY valuesvalues areare inin remember each of the commands.commands. Each commandcommand pairs. prompts you for the correct entries. The entire program is written in BASIC, notnot in machine language, so you you can enter approximately 2000 characters in an 8K can see howhow itit is done. Functions: Write to memory, PET —— about about the the lengthlength ofof aa fullfull page letter. CompleteComplete E read memory/disassemble, save memorymemory onon tape,tape, load input and editing features: enter text, deletedelete lines,lines, insertinsert from tapetape toto memory,memory, executeexecute aa machinemachine languagelanguage lines between thethe lineslines ofof existingexisting text,text, dodo substitutionssubstitutions program, exit toto BASIC.BASIC. Four pages ofof documentation. within a line, oror replacereplace one line with another, YouYou can also move a block of lines from one place to another in TUTOR $19.95 the text. YouYou can alteralter the left margin for indentation,indentation, A beginner's guide to PETPET BASICBASIC andand toto thethe cursor or adjust the right margin(althoughmargin(although therethere isis nono provision control features which make PET the the #1#1 personal for right-hand justification).justification). ThereThere areare provisionsprovisions for computer available. Over 400 screensful ofof informationinformation filling aa lineline withwith aa specifiedspecified character, or centering a are presented in 20 lessons, provided on both sidessides of repeated character on a line. Twenty-fiveTwenty-five pagespages ofof each of two C-45 cassette tapes, five lessons per side. documentation provided. All the major BASICBASIC keywords, plus exercises, quizzes, and a few wisecracks. A must for all beginners. STAT IIIIII $7.95 A good program for calculating elementary stats. 200 PET BASIC COMPLEATCOMPLEAT $29.95 data points, edit afterafter entry.entry. Conversational, Conversational, nono DATADATA This 170+ page manual is the companion for the statements. StatsStets provided are: mean,mean, median,median, mode,mode, TUTOR tapes. tapes. TheThe manual manual isis drilleddrilled forfor a standard 3- high value, low value, range, variance, standard hold binder, is indexed for easy reference, and deviation, sample std. deviation, averageaverage deviation, andand reproduces (so(so far as is possible withoutwithout aa PET printer) printer) an automatically scaled bar chart. exactly the data presented in the tapetape andand displayeddisplayed on the screen. WAREHOUSE $7.95 The object of the game is to survive an eight-hour day PET TUTORIAL PACKAGEPACKAGE $39.95 — for as many days as you can — asas supervisorsupervisor inin thethe Because we feel that thethe TUTOR' TUTOR' tape andand thethe PET PET Warehouse. SelectSelect levellevel ofof expertise:expertise: 1 minute of BASIC COMPLEAT manual manual constitute constitute anan unbeatableunbeatable playing timetime = 1 hour of "real" time. If you make a learning tool forfor beginningbeginning PETPET people,people, wewe offer the setset mistake, you'll get a memo from thethe BossBoss — andand ifif youyou as a package dealdeal — — you you get get the the 170+ 170+ pagepage manual manual (as as let youryour workboardworkboard overflow, you'll be fired!fired! of this writing, therethere areare 183 pages) plus the two C-45 cassette tapes, forfor under $40. Save almost $10.00 on the set. THE PAPERPAPER guarantees guarantees that that eacheach ofof thesethese programsprograms CMC/WPP $29.50 will perform as claimed herein.herein. IfIf your copy of any The Connecticut Microcomputer WordWord ProcessingProcessing program fails to load, send itit back toto us —— we'llwell ship Program turns your PET intointo aa powerfulpowerful texttext you a new copy. Record aa programprogram ofof your own on the processing system.system. You cancan enterenter texttext in upper and back of the tape, however,however, soso wewe cancan checkcheck the tapetape lower case letters,letters, editedit thethe text,text, and format the texttext forfor head alignment. finished printing.printing. Due toto the limit ofof availableavailable memory, IL)

MORE ABOUT RESEQUENCERESEQUENCE by Brian Brane Nestar Systems, 810 GarlandGarland Drive.Drive, PaloPalo Alto, CACA 94303 hashas thethe CLUSTER/ONE,CLUSTER/ONE, a a low low costcost distributeddistributed processing alternative to BASICBASIC timesharing. The The RESEQUENCE program (page 20, issue #8) is a The RESEQUENCE program (page 20, issue #8) is a central unit (the(the QUEEN),QUEEN), via a high-speed data bus, big help, but itit cannotcannot accomodateaccomodate somesome of the longerlonger connects up to 1515 PETsPETs as terminals (the(the DRONES).DRONES). programs. To overcome thatthat problem, II added the Programs andand datadata files are shared among the users, following lineslines toto thethe program.program. stored on two IBM-compatible 8-inch floppies; eacheach of which hold 315K bytesbytes ofof data. Disk transfertransfer rates are @LEAR SCREEN SCREEN 6.k..119SOR 8,UIRSOR UP $=CURSOR DOWN UP $=CURSOR DOWN 250K bytes/second, managed via an LSI floppy disk 570 T=33647:S=T-879:E+23:?"@$$$$$$$$$$$$$$$$$$" controller ship. No internal modifications required. In 641 FORK1326T01017:A=PEEK(K+32630):POKEK,A:FOF1K1326T01017:A=PEEK(K+32630):POKEK,A: fact, ifif aa CLUSTER/ONECLUSTER/ONE Queen Queen fails, fails, itit cancan bebe replacedreplaced POKEK+32630,0:NEXTK by a Drone in a matter of minutes. A full set of Utility 642 ?"PRESS?"PRESS PLAY ON ON TAPE TAPE # # 1&":IF 1&":IF PEEK(59411)1 programs for maintenance and backup, and separate THEN642 documentation for the end users; disk drives, 643 FORK-1T0100:NEXTK:IFFORK=1T0100:NEXTK:IF PEEK(59411)1PEEK(59411)1 THEN642THEN642 controller, bus electronics, additional memory,memory. power 644 ?"?"CHR$(34)"&&&&"CHR$(34)":LOAD:$$"?"?"CHRS(34)"&&84"CHR$(34)":LOAD:$$" supplies and cooling for $7500. WriteWrite toto NESTAR NESTAR 645 ?"FORK3456T033647:A=PEEK(K-32630):POKEK,A . SYSTEMS INC. INC. for for further further details.details. NEXTK:SYS(32791)&&&&&&&" NEXTK:SYS(32791)&&&&&&&" 646 POKE525,2:POKE527,13.POKE528,13:END

These additionsadditions store the machine language program in Video RAMRAM Line Line 641 641 temporarily temporarily storesstores partpart ofof thethe ELLIAM ASSOCIATES,ASSOCIATES. 24000 24000 Bessemer Bessemer Street, Street, machine language program in the secondsecond cassette Woodland Hills, CA 91367 announces cassette labels buffer while your program is loaded from Tape UnitUnit #1.#1. on pinfeedpin feed backing. They're white,white, fanfold, and Line 645 puts the programprogram backback inin VideoVideo RAMRAM and then $5.90/100. WriteWrite to WilliamWilliam D. Roch forfor largerlarger quantityquantity renumbers your program. Be suresure thatthat your programprogram prices, for pinfeed diskette andand mailing labels,labels, andand (thethe oneone to bebe renumbered)renumbered) isis thethe firstfirst program program PET PET delivery information. will find after youyou presspress play in line 642. BEST PETPET BETBET YET!YET! 4 A COMPLETE LINE OF MICROCOMPUTER ACCESSORIES INCLUDING

THE PETPET MEMORYMEMORY EXPANSION UNIT UNIT THATTHAT SIMPLY PLUGS IN QUALITY CASSETTES gar - 8k additional staticstatic RAM RAM -Phillips style cassette - Plugs intointo PET'sPET's external external memory memory expansionexpansion port - Error free(for densitiesdensities - Built inin heavy heavy dutyduty regulatedregulated perper supplysupply used byby homehome computers) - Completely assembled,wired,burned-in and tested - Norelco box(2 piecepiece hardhard - Attractive cabinet cabinet complements complements PET'sPET's appearance appearance plastic) -Illustrated user'suser's manual manual -50 feet C-10,(5 minutes)minutes) PEM-8K PRICE:PRICE: $297,PLUS $6.00$6.00 SHIPPINGSHIPPING BOX OF TEN,W1THTEN,W1TH LABELS:LABELS: $14.95,PLUS.$1.45 SHIPPINGSHIPPING FitGH UTILITY SOFTWAREHIGH UTILITY FOR SOFTWARE YOUR FOR YOUR PET PET NOTES PEM — CALCULATOR @ $ 7.95 The PEMPEM •-CALCULATOR CALCULATOR provides provides* a wide wide range range of of math math and and financial financial functions functions including: including: • N I ■n Trigonometric • LoomLogai:ithms • Anti4ogsAnti4ogs • inverseinverse functionsfunctions Virginia residentsresidents • Hyperbolic functions • InterestInterest • PeriodicPeriodic paymentspayments • PresentPresent value add 4%4% tax ■n Annuity • SinkingSinking fund

The PEM - CALCULATORCALCULATOR is is a a reve-se reve-se PolishPolish stack stack operated operated calculator calculator written written In BASIC forfor the the Prices effective PETO'sPET 11's 6502 micro-processor micro-processor and requires 12K of memory. Jan 1,I, 1979 MICRO-SETMICRO - SET ° II (Basic(Basic Utili-ties) Utili-ties) f3f3 $$ 14.9514.95 SET e, which stands forfor SoftwareSoftware Engineering Tool,Tool, allowsallows thethe useruser toto manipulatemanipulate otherother programsprograms inin aa Foreign'and . very convenient fashion. MICRO-SETC I I provides thethe followingfollowing functions inin aa mannermanner designed and . air tested for easeease ofof use:use: shipments extraextra CREATE TAPE TAPE — — makes makes an an ASCII ASCII file file copycopy of of program, program, subroutinesubroutine or collection of lines for addition to another program.program, ADD FROM TAPE uses enan ASCII file file tape tape made made by by Create Create Tape Tape functions functions to to add add previously previously stored stored Volume discountsdiscounts lines toto thethe programprogram presentlypresently in the computer.computer. DELETE — — removes removes from from your your program program all all lines lines numbered numbered between between limitslimits youyou specify.specify. available PROGRAM INFOINFO — reportsreports the number of lineslines inin youryour program, program, first first and and last last line line numbers, numbers, and and the the number of bytes free. PET isis aa productproduct of RENUMBER — — change change line line numbers numbers in in a arange range you you specify specify to to new new numbers numbers starting starting with with a a number number you designate, increasing at a step sire of your choice,choice. ProvidesProvides informationinformation forfor manuallymanually changingchanging Commodore Business Business .targetsmrtargets of of GOTO, GOTO, GOSUB GOSUB and and IF IF - - -- -THEN THEN statements. statements. Machines, Inc.Inc. 8K of user memory required BLANK LABELS +4- SUPERSUPER SOFTWARE ! ! 40P- -No advertising - No printingprinting BIG - -ITALITAL CLOCK for the 8K PET. $5.95 BIG- CLOCK for the 8K PET. $5.95 - Mark with ballpoint, nO ‘ Mark with ballpoint, Big Digits Best-looking DisplayDisplay 101:t. felt-tip.rubber stamp,stamp, or typewriter 12 or.24 Hour Change any time Seconds tick off evenly....Compare! 60 cassette labels, 6060 boxbox Easy,natural questions lead you clearly. labels (10(TO Red,10Red,10 Green,Green, Easy,natural questions lead you clearly. 10 Blua,10 YellowYellow && 20White)2OWhite)

PROTECT YOUR COMPUTER FROM FROM DUST DUST AND AND SPILLS SPILLS PRICE: 6060 Labels,$4.80Labels,$4.80 - --HeavyHeavy duty duty cloth cloth backed vinyl vinyl - Custom fitted fitted -Rugged heavy heavy duty duty sticking sticking - NEW-CURSOR 4111/144e .iii_ -Corded seamsseams lg , - Available inin gold,olive, Reset your PET withoutwithout chestnut and black touching the power switch!!! PRICE PET COVER 18.95 plus $1.25 SHIPPING switch!!! PRICE PET COVER 18.95 plus $1.25 SHIPPING Save wear an the CRT. TRS-80 COVERCOVER $9.95 plus $.75 SHIPPING Save wear on the CRT. Other coverscovers available.available. Write for Save wear on the power details. supply. Simple Kit...No soldering. INTERNATIONAL TECHNICAL SYSTEMS,SYSTEMS, INC.INC. 5 minute installation. P. 0. BOX 264, WOODBRIDGE, VIRGINIA 22194 5 minute installation. WE ACCEPT VISAVISA AND MASTERMASTER CHARGE Complete Instructions. CUSTOMER SERVICES, SERVICES, RICHMOND, RICHMOND, VIRGINIA VIRGINIA 18041 18041 262-9709 262-9709 A BARGIN AT $4.95 "Mortimer"Mortimer Snerd"Snerd" writeswrites thatthat he'she's 1515 yearsyears oldold andand John HirschHirsch writeswrites toto letlet usus knowknow this:this: would like to share with us the following tidbits: SYS(64840) calls the screen test program — but you Try this program: have to turn off the PET to recover. When you call USR 10 FORFOR 1=4.8I-4,8 TO TO 6.3 6.3 STEPSTEP .33 without POKEing the address into locations 1 & 2, you 10 PRINT I get an ?ILLEGAL QUANTITY ERROR because the 30 NEXT address in thosethose locationslocations onon power-uppower-up isis tnethe addressaddress You might expect the last I printed to be 6.3 — instead, of the routine printing that message! And, to avoid itsits 6.00000001!6.00000001! II assumeassume thisthis isis duedue toto the impossibility abnormal RETURN key functions after closing a file. of representing .1.1 exactlyexactly inin binarybinary arithmetic.arithmetic. ToTo seesee POKE 3.0, then a few garbage letters, then hit why, try solving: RETURN. But the program has to include a CLOSE statement —— oror thethe RETURNRETURN keykey doesn'tdoesn't work.work. 2X2X=.1 1 XLOG(2)=LOG(.1) X=LOG(X=LOG(.1)ce3 1}Qas -3.3219281 -3.3219281 National Artificial Intelligence Laboratory (NAIL), LOG(2) P.O. Box F, Mobile, AL 36601 has two new machine languagelanguage programsprograms forfor thethe PET.PET. SYS7171SYS7171 isis aa machinemachine But if we try 21'-3.3219281, wewe getget .099999997.099999997 —— thethe languagelanguage monitormonitor which allows the user to program in limitlimit ofof PET'sPET's nine-digit display.display. ThisThis lacklack ofof machine language or in BASIC without destruction of correspondence between decimal and binary makes it the monitormonitor onceonce it'sit's loaded.loaded. TheThe useruser cancan jumpjump fromfrom risky to use ''IF X=X- (some constant) THENTHEN BASIC to SYS7171 and back again freely, to append when we are comparing floating point numbers. Every one BASIC program to another, and spend only $29.71 experienced programmer knows (and keeps forgetting) doing it all. SYS8181 is a machine languagelanguage this. renumbering program using only 1K of RAM and costing $18.71. The user can select a beginning line I enjoyed Roy Busdiecker's article on date formats inin number and increment amount and SYS8181 correctly #9. The only thing left out was the algorithm for renumbers every GOTOGOTO andand GOSUBGOSUB inin thethe program.program. converting floating point to PET 5-byte. Those Both programs come with manuals. Write to Evan interested can look up Mark Zimmerman's articlearticle inin Foreman for delivery information. "PEOPLE'S COMPUTERS'", Sept/Oct '78, V7V7 #2,#2, p.p. 16.16.

PET USERS

Glenn Schwartz St. Louis PET Users Independent PET Group 807 Avon (Mary Perkinson) 22 Firs Walk, Tewin Wood Philadelphia, PA 19116 (314) 432-5225 Welsyn, Herts., UK John Loofbourrow Northern VA PET Users PET Users Group ACGNJ 2054 Eakins Ct. 2001 Bryan Tower Suite 3800 (201) 233-7068 Reston, VA 22091 Dallas, TX 75201 United PET Users Shelly Wernikoff Capital District PET Users 1929 Northport Or #6 2731 N Milwaukee Ave (Ben Green) Madison, WI 53704 Chicago, IL 60647 (518) 370-1820 Twin Cities PET Users SPHINX Central Illinois PET Users (John Fung) (415) 451-6364 2730 Townway Rd. #E-54 (612) 376-5465376-5465 Vancouver PET Users Group Danville, IL 61832 Peter Oakes Box 35353, Station E PET Users of Japan 2235 Lakeshore Drive Vancouver, BC, Canada Soichiro Moridaira Muskegon, MI 49441 Lincoln Computer Club Shinsen Park Himu, Rm #150 Sacramento PET Workshop 750 E Yosemite 4-13 Shinsencho P.O. Box 28314 Manteca, CA 95336 Shibuyaku, Tokyo, Japan 150 Sacramento, CA PET NET David Liem PUG (Mercury Room) 14.240 MHz 14361 Warwick Street 310 Showers Drive 1500 UCT (10 AM CDT) Sundays Detroit, MIMI 4822348223 Mountain View, CA PET NET II Larry Williams BAMUG 7.205 MHz P.O. Box 652 1450 53rd StreetStreet 9 AM PDT Fridays San Antonio, TXTX 7829378293 Emeryville, CA Richard PrestienPrestien David SmithSmith —— NOCCCNOCCC 6278 SW 14th Street 3030 TopazTopaz #A#A Miami.Miami, FLFL 3314433144 Fullerton, CA 92631 Have we missed anyone? Let us know who and where youyou are!are! YES! PleasePlease enterenter mymy New SubscriptionSubscription OrderOrder forfor allall tenten issuesissues of of Volume Volume 1 1 Renewal SubscriptionSubscription orderorder for all ten issuesissues of Volume 2 New SubscriptionSubscription OrderOrder forfor allall tenten issuesissues of of Volume Volume 2 2 Full payment of $15.00 per volume ordered isis enclosed.**enclosed.**

NAME (Please print or type) ADDRESS (Street,(Street, not not P.O. P.O. Box) Box)

CITY STATE ZIPZlP Please charge my /MC/VISA/BAC/ ##

Master Charge Interbank # Exp. Date Required CreditCredit CardCard Signature Signature

Please ship the following Software to me within two weeks: —

STAT III $ 7.95 WAREHOUSE $ 7.95 DATA RETRIEVAL $10.00 CHASE $10.00 DATA EDIT $10.00 MICROMAZE $ 7.95 STAT II $20.00 BLACKJACK $10.00 STAT IIII $20.00 BLOCKADE $10.00 SPACE FIGHT $10.00 DEFLECTION $10.00 HOSTAGE $ 7.95 STARTREK 2001 $10.00 AIR-SEA WAR $ 7.95 XMON $15.00 TUTOR $19.95 CMC/WPP $29.50 BASIC COMPLEAT $29.95 TUTOR PACKAGE $39.95

I understand tthat eficatt ivifife anyatnaype ofo.f thethe programsprograms failfail toto load,load, THETHE PAPERPAPER willwill sendsend meme aa replacementreplacement asas soonsoon asas II return the defectivedef tape.

NAME (Please printprint oror type)type) ADDRESS (Street,(Street, not not P.O. P.O. Box) Box)

CITY STATE ZIP Pleaselease chargecharge mymy /MC/VISA/BAC//MC/VISA/BAC/ ##

Vaster ChargeCharge InterbankInterbank # # Exp. Date

Required CreditCredit Card Card Signature Signature

••• • 4.: a: : es: es are available for billing or for C.O.D. delivery. Orders submittedsubmitted withoutwithout paymentpayment willwill bebe _ .1: =TiTr. folks.folks. butbut nearlynearly 1111Oth 10th of of the the subscribers subscribers to to Volume Volume 1 1 asked asked for for billing billing —— andand stillstill haven'thaven't :ar: QUALITY SOFTWARE SOFTWARE FOR FOR THE THE PET* PET* 001 *PET Is Is aa productproduct ofof CommodoreCommodore Business Business Machines,Machines, Inc.Inc.

What does quality software mean? First, it means programs that workwork thethe wayway you'dyou'd RRt.,, them to, easily and naturally. It means internal operating instructions and internal them to, easily and naturally. It means internal operating instructions and internal documentation, as well as system design and modular construction toto easeease modificationmodification or maintenance. Finally, quality software is provided on quality tapestapes (and(and withwith MICROMICRO SOFTWARE SYSTEMS, itit meansmeans aa quality,quality, hardhard plasticplastic casecase forfor thethe casette!).casette!).

SWEE-PING(TM)SWEE-PINGT" a asimple simple but but captivatingcaptivating CHEQUE-CHECK(TM)CHEQUE-CHECKTM end the hassle in getting end the hassle in getting bouncing-ball game. The number of ways it checkbook and bank statement to balance. can be played is limited only by the imagination Review or change entries, verify checkbook of the player. $5.95 line-by-line. Even wives use it!it! $7.95$7.95

METRIC-CALCTHMETRIC-CALC(TH) turns the PET into a powerful turns the PET into a powerful MEM-EXPLORER(TM)MEM-EXPLORERTH can can be be combined combined stack-operated RPN calculator with scientific automatically with existing programs, showsshows functions, metric conversions. 2020 levels,levels, exactly how and where they are stored in 20 memories. $7.95 memory. Described in THETHE PAPERPAPER articles. $7.95

BILLBOARDTMBILLBOARD— lets lets you you type type message message upup toto 254254 characterscharacters (incl.(incl. pause,pause, flash), which is then displayed in 1" letters moving horizontally. RepeatsRepeats continuously.continuously. NoNo static,static, snow.snow. GoodGood salessales display!display! $49.95 MICRO SOFTWARESOFTWARE SYSTEMSSYSTEMS Send check or money order. Allow -- two weeksweeks forfor checkcheck toto clear.clear. VAVA residents P.O. Box 1442, Woodbridge, VA 22193 add 4%43/4 tax.tax. DealerDealer Inquiriesinquiries invited,

DintttttittmtiettiettittritinttrettP THE PET ININ THETHE CLASSROOM — — continued continued er and a grade-recording program is being developed forfor use with the printer.

Any correspondence withwith othersothers interestedinterested in _ . education is welcome. Some of the CAI programs are &arC - Wk. 1-1•1_. • ILIWRIMI available for exchange, and the school computercomputer clubclub 1MI MIBWO has many games that are availableavailable for exchange.exchange. JustJust IMILM_ -41Q11h..11120.1. WHAPAPS. write: JohnJohn Fultz,Fultz, LincolnLincoln School,School, 750 E.E. Yosemite, MK"-

Manteca, CA 9533695336 •-•:111 -40 n 4444444446444443444461.144.41I34 fd.f.ba

THE PAPERPAPER SECOND CLASS POSTAGE P 0 BOXBOX 4343 PENDING AT.AT . NORRISTOWN PA 194031940 AUDUBON PAPA 1940719407 3

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