Category Archives: TRS-80 Model 1

Steve Bjork TRS-80 Model 1 source code…

From “The Big List of TRS-80 Software” I found two early Steve Bjork programs. These appear to be the two programs that appeared on the People’s Software tape:

PeoplesSoftware-TRS80-Model1

The first is a Bio-Rhythm program listed as biortsb.bas (which I assume the “sb” at the end is Steve Bjork):

10 REM  BIO-RHYTHM ------ BY STEVE BJORK
20 DIMA(150)
30 FORX=1TO20
40 READA(X)
50 RESTORE
60 FORX=1TO20
70 READA(X)
80 NEXTX:A=0
90 FORX=9TO20
100 A=A+A(X):A(X+11)=A
110 NEXTX
120 CLS:PRINT" B I O - R H Y T H M"
130 PRINT:PRINT" BY STEVE BJORK":PRINT
140 INPUT"WHO ARE YOU";A$
150 INPUT"WHAT IS YOUR BIRTHDATE (M,D,Y)";M,D,Y
160 INPUT"AND THE DATE FOR CHART (M,Y)";B,C
170 Z=((C-Y)*365)-D-A(M+20)+A(B+20)+INT((C-Y)/4)
180 IF(Y/4=INT(Y/4))*(M<3) Z=Z+1
190 IF(C/4=INT(C/4))*(B>2) Z=Z+1
200 CLS
210 PRINT@960,""
220 FORX=1TO31
230 SET(17,X):SET(18,X):SET(49,X):SET(50,X):SET(81,X):SET(82,X)
240 SET(113,X):SET(114,X)
250 SET(33,X):SET(65,X):SET(97,X)
260 NEXTX
270 FORX=17TO114
280 SET(X,0):SET(X,32)
290 NEXTX
300 FORX=0TO30STEP5
310 SET(16,X):SET(19,X):SET(48,X):SET(51,X):SET(80,X):SET(83,X)
320 SET(112,X):SET(115,X)
330 NEXTX
340 FORX=5TO30STEP5
350 PRINT@INT(X/3)*64+3,X;:PRINT@INT(X/3)*64+58,X;:
360 NEXTX
370 PRINT@713,"LOW";:PRINT@729,"LOW";:PRINT@745,"LOW";
380 PRINT@720,"C";:PRINT@736,"C";:PRINT@752,"C"
390 PRINT@ 724,"HIGH";:PRINT@740,"HIGH";:PRINT@756,"HIGH"
400 PRINT@781,"PHYSICAL";
410 PRINT@796,"EMOTIONAL";
420 PRINT@813,"MENTAL";
430 PRINT@857,"NAME------------";A$
440 PRINT@921,"BIRTHDATE-------";M;"/";D;"/";Y
450 PRINT@985,"CHART DATE------";B;"/";C;
460 IF(C/4=INT(C/Y))*(B=2) A(10)=29
470 FORX=1TOA(B+8)
480 P=Z-INT(Z/23)*23:E=Z-INT(Z/28)*28:I=Z-INT(Z/33)*33
490 S=6.28319*(P/23)
500 GOSUB660
510 SET(INT(S*13)+34,X)
520 S=6.28319*(E/28)
530 GOSUB660
540 SET(INT(S*13)+66,X)
550 S=6.28319*(I/33)
560 GOSUB660
570 SET(INT(S*13)+98,X)
580 Z=Z+1
590 NEXTX:A(10)=28
600 PRINT@832,"FOR A NEW CHART";
610 PRINT@896,;"ENTER A '1'";
620 INPUTA
630 IFA=1GOTO140
640 CLS
650 STOP
660 T=S:U=S
670 FORW=1TO7STEP2
680 U=U*T*T
690 S=S-(U/A(W))+((U*T*T)/A(W+1))
700 U=U*T*T
710 NEXTW
720 RETURN
730 DATA6,120,5040,362880,39916800,6.22702E09
740 DATA1.30767E12,3.55687E14
750 DATA31,28,31,30,31,30,31,31,30,31,30,31

The second is a Perpetual Calendar program listed as percalsb.bas:

5  REM....PERPETUAL CALENDAR PROGRAM
6 REM....FOR RADIO SHACKS TRS-80
7 REM....BY STEVE BJORK
8 DIMA(150)
9 CLS:PRINT@400,"PERPETUAL CALENDER BY STEVE BJORK"
10 PRINT@ 448,"ENTER MONTH AND YEAR (MM,YY)";:INPUT M,Y
11 IF (M>12)+(M<1)THEN10
17 IF Y<100 THENY=Y+1900
18 RESTORE:FOR I=1 TO 12:READ V:NEXT I
19 FOR I=1 TO M:READ A$:NEXT I
20 B$=" ":L=0:IF INT(Y/4)<>(Y/4)THEN50
30 IF INT(Y/100)=(Y/100) THEN50
40 B$="LEAP-YEAR":L=1
50 T=INT((Y-1893)/4)
60 C=(Y-1893+T)/7:C=INT((C-INT(C))*7+.5)
90 RESTORE:FOR I=1 TO 12:READA(I):NEXTI:A(2)=A(2)+L
91 D=0:IF M=1 THEN 100
92 FOR I=1 TO M-1:D=D+A(I):NEXT I
100 D=(D+C)/7
110 D=INT((D-INT(D))*7+.5)
111 IF D=0THEND=7
120 CLS:PRINT@ 22,A$;" ";Y;" ";B$
150 T=0:FOR I=(D-2) TO 0 STEP-1:T=T+1:A(T+12)=(-I):NEXTI
160 P=1:FOR J=D TO 7:A(J+12)=P:P=P+1:NEXT J
164 RESTORE
165 W=0:FOR I=1 TO 12:READ X:NEXTI:FORI=1TO12:READB$:NEXTI
166 FOR J=8 TO 56 STEP 8:READ B$:PRINT@64+J,B$:NEXTJ
167 A$=" ":H=0:READ A,A$:IF A=0 THEN 170
168 IF INT(A)<>M THEN167
169 H=INT((A-INT(A))*100+.5)
170 FOR I=128 TO 832 STEP 128
180 P=0:FOR J=8 TO 56 STEP 8:S=I+J
190 P=P+1:Q=A(P+12)+(W*7)
191 Z=0:IF Q<10 THENZ=1
200 IF (Q<=0)+(Q>A(M))THEN220
210 PRINT@ S+Z,Q
211 IF H<>Q THEN 220
212 PRINT@ S+63,A$
220 NEXT J:W=W+1:NEXT I
270 END
1000 DATA31,28,31,30,31,30,31,31,30,31,30,31
1100 DATAJANUARY,FEBRUARY,MARCH,APRIL,MAY,JUNE,JULY,AUGUST
1200 DATASEPTEMBER,OCTOBER,NOVEMBER,DECeMBER
1300 DATASUN,MON,TUE,WED,THU,FRI,SAT
1400 REM...HOLIDAYS (M.D)
1500 DATA1.01,NEW YR,12.25,XMAS,2.14,VAL,7.04, 4TH,4.01,FOOL
1510 DATA10.31,HAL'WN
1800 DATA0,END

I have so far been unable to locate additional information on People’s Software, but it was produced by:

  • computer information exchange, inc.
  • box 158
  • san luis rey ca 92068

Can you find more about them?

Until then…

Steve Bjork’s TRS-80 Model 1 days

Steven Robert Bork (SRB Software) was such an iconic name in the Tandy/Radio Shack TRS-80 Color Computer community. Seeing his name on title screens of games etched it into my memory more than any other game author I can recall.

Recently, Roger Taylor spent over $6700 to acquire some of Bjorks software source code (disks and printouts) from an auction house. He has been discovering some interesting things, such as internal development tools Steve used as well as unfinished and unreleased programs. The archive goes back to Steve’s TRS-80 Model 1 days in the late 1970s.

One year before Steve wrote Popcorn for the CoCo, he had Space Ball for the Model 1:

I had also heard mentions of some multi-voice software music program he wrote. This was Soft Music:

I do not know how to use it, but when I figure it out, I will make a longer video of it. There appears to be several disks of songs available on a TRS-80 archive site, but I do not know how to get them in to the emulator yet.

There is also a Space Balls 2 which seems to be the same except for a countdown before the next ball drops.

Still a mystery is Galactic Fighter (not to be confused with a completely different game by that name released for the CoCo in 1984 by a different author). In a 2007 interview, Bjork described his Galatic Fighter game as similar to Galaxian, but predating it by three months. I see Galaxian listed as a September/November 1979 game, but I do not know when it was released in the USA. Wikipedia says Galaxian was the highest grossing game of 1980. I did manage to find this screenshot:

Roger Taylor has disks for this game, but is still working on safely getting them preserved and, hopefully, in a form that can run in an emulator.

Also during my research were two BASIC programs by Bjork – Perpetual Calendar and Bio-Rhythm. These appeared in a cassette tape collection called People’s Software./

Here is a link to the source of Perpetual Calendar that is supposed to be runnable in a web emulator, but I could not figure out how to start it:

https://willus.com/trs80/?-a+1+-p+10272+-f+1

And here is Bio-Rhythm on the same emulator site:

https://willus.com/trs80/?-a+1+-p+1226+-f+1

I do not know the date these were published, and do not see a date in the source listing. There may be a date in one of the other programs in the collection that might give us a clue.

Steve also created PEN BASIC, a program that added commands to the TRS-80 Model 1 for using a light pen device. I have heard him mention that he worked on a light pen, but never knew anything about it. Here is an ad mentioning it:

I also found a magazine article that goes in to details on the commands that PEN BASIC provides, and discusses how to use it.

And there is more to still be located… I see references to other things he created in the TRS-80 Model 1 days that I have yet to go searching for.

But one thing I have discovered is that Steve was known outside the pages of Color Computer magazines such as Rainbow. I find him referenced in articles in magazines of the day I had heard of (such as K-Power) and plenty I had never heard of (such as Softline and Today). There are some interviews, quotes, and a number of game reviews that mention his name as the author.

I now have a list of questions I wish I could ask Steve. When we were hanging out in Southern California, the subject of CoCo stuff would inevitably come up from time to time, but I wish I had dug deeper and learned more about some of his other works.

To be continued…