10 REM SOUND GENERATION PROGRAM 
20 REM N$ IS NAMES OF SOUNDS 
30 REM D(X,Y) IS DATA VALUE X FOR SOUND Y 
40 REM LR IS LINE NUMBER OF SOUND DATA ON DISPLAY 
50 REM BS IS NUMBER OF BYTES INTO LINE OF DISPLAY FOR SHAPE BITS
60 REM BC IS NUMBER OF BYTES INTO LINE OF DISPLAY FOR CHANNEL BITS
70 REM RN$ IS REGISTER NAME 
80 REM TH IS TONE REGISTER, LOW LIMIT 
90 REM TL IS TONE REGISTER, LOW LIMIT
100 REM EH IS ENVELOPE PERIOD, HIGH LIMIT 
110 REM EL IS ENVELOPE PERIOD, LOW LIMIT 
120 REM NH IS NOISE FREQUENCY, HIGH LIMIT 
130 REM NL IS NOISE FREQUENCY, LOW LIMIT 
140 CLEAR 1000
150 GOSUB 43000
160 FAST 
170 VINPUT 23*80,"PRESS 'RETURN' TO BEGIN EXECUTION";, LINE A$
180 REM SET STARTING RANGES FOR VARIABLES 
190 TH=30000:TL=30
200 EH=8:EL=.1
210 NH=31:NL=0
220 REM DEFINE DATA ADDRESSES 
230 VA=PEEK(&105)+256*PEEK(&106):POKE VA+&7FF,12
240 PR=128:PD=129
250 DIM N$(19),D(9,19),RN$(13)
260 FILL 32:POKE VA+&7FF,12
270 CR$=CHR$(&7F)
280 RESTORE 
290 REM LOAD LINE NUMBER ARRAY 
300 FOR I=0 TO 9
310 READ LR(I)
320 NEXT 
330 REM LOAD LINE ADDRESS MAP FOR SHAPE BITS 
340 FOR I=0 TO 3
350 READ BS(I)
360 NEXT I
370 REM LOAD LINE ADDRESS MAP FOR CHANNEL ENABLE BITS 
380 FOR I=0 TO 5
390 READ BC(I)
400 NEXT I
410 FOR I=0 TO 13
420 READ RN$(I)
430 NEXT I
440 DATA 6,7,8,11,14,15,16,19,20,23
450 DATA 17,27,40,48
460 DATA 17,22,27,40,45,50
470 DATA "R0  - CHANNEL A, FINE TUNE"
480 DATA "R1  - CHANNEL A, COARSE TUNE"
490 DATA "R2  - CHANNEL B, FINE TUNE"
500 DATA "R3  - CHANNEL B, COARSE TUNE"
510 DATA "R4  - CHANNEL C, FINE TUNE"
520 DATA "R5  - CHANNEL C, COARSE TUNE"
530 DATA "R6  - NOISE PERIOD"
540 DATA "R7  - ENABLE"
550 DATA "R10 - CHANNEL A, AMPLITUDE"
560 DATA "R11 - CHANNEL B, AMPLITUDE"
570 DATA "R12 - CHANNEL C, AMPLITUDE"
580 DATA "R13 - ENVELOPE, FINE TUNE"
590 DATA "R14 - ENVELOPE, COARSE TUNE"
600 DATA "R15 - ENVELOPE SHAPE"
1000 FILL 32:VPRINT 30,"MAIN MENU"
1010 VPRINT 240,"KEY  FUNCTION"
1020 VPRINT 400," A - DEFINE NEW SOUND"
1030 VPRINT 480," B - MODIFY EXISTING SOUND"
1040 VPRINT 560," C - PLAYBACK SOUND"
1050 VPRINT 640," D - LIST ALL SOUNDS"
1060 VPRINT 720," E - EXPERIMENT"
1070 VPRINT 800," F - PRINT SOUND"
1080 VPRINT 880," G - CHANGE SOUND NAME"
1090 VPRINT 960," H - SAVE SOUND"
1100 VPRINT 1040," I - LOAD SAVED SOUND"
1110 VPRINT 1120," J - DISK DIRECTORY"
1120 VPRINT 1200," K - MODIFY LIMITS"
1130 VPRINT 1280," L - EXIT PROGRAM"
1140 IP=CINP(3)
1150 ON IP-64 GOTO 2000,3000,4000,5000,6000,7000,8000,9000,10000,11000,12000,13000
1160 GOTO 1140
2000 REM DEFINE NEW SOUND 
2010 GOSUB 30000
2020 GOSUB 39000
2030 SN=RV
2040 IF N$(SN)="" THEN 2060
2050 VPRINT 119,"SOUND ALREADY EXISTS":GOTO 2020
2060 VPRINT 119,SPC(20)
2070 VINPUT 44,"SOUND NAME: ";,N$(SN)
2080 VPRINT 44,SPC(36)
2090 VPRINT 44,N$(SN)
2100 GOTO 3050
3000 REM MODIFY EXISTING SOUND 
3010 GOSUB 30000
3020 GOSUB 39000
3030 SN=RV
3040 IF N$(SN)="" THEN VPRINT 119,"SOUND NOT ON FILE":GOTO 3020
3050 GOSUB 35000
3060 LI=0
3070 VPRINT LR(LI)*80,CR$
3080 IP=CINP(3)
3090 IP$=CHR$(IP)
3100 IF IP$="M" THEN 1000:REM MAIN MENU 
3110 IF IP$="D" THEN 3150:REM STEP DOWN 
3120 IF IP$="U" THEN 3190:REM STEP UP 
3130 IF IP$="V" THEN GOSUB 40000:REM VARY 
3140 GOTO 3070
3150 IF LI>=9 THEN LI=9:GOTO 3080
3160 VPRINT LR(LI)*80," "
3170 LI=LI+1
3180 GOTO 3070
3190 IF LI<=0 THEN LI=0:GOTO 3080
3200 VPRINT LR(LI)*80," "
3210 LI=LI-1
3220 GOTO 3070
4000 REM PLAYBACK SOUND 
4010 GOSUB 30000
4020 GOSUB 39000
4030 SN=RV
4040 IF N$(SN)="" THEN VPRINT 119,"SOUND NOT ON FILE":GOTO 4020
4050 GOSUB 35000:GOSUB 42000
4060 VPRINT 119,"PRESS ANY KEY TO RETURN TO MAIN MENU"
4070 IP=CINP(3):IP=0
4080 FOR I=0 TO 13
4090 OUT PR,I:OUT PD,0
4100 NEXT I
4110 GOTO 1000
5000 REM LIST ALL SOUNDS 
5010 FILL 32
5020 VPRINT 80,"SOUND NUMBER      NAME"
5030 FOR I=0 TO 19
5040 VPRINT 80*(I+3),I;TAB(18);N$(I)
5050 NEXT I
5060 VINPUT 23*80,"PRESS 'RETURN'";, LINE A$
5070 GOTO 1000
6000 REM EXPERIMENT MODE 
6010 GOSUB 30000
6020 GOSUB 39000
6030 SN=RV
6040 IF N$(SN)="" THEN VPRINT 119,"SOUND NOT ON FILE":GOTO 6020
6050 GOSUB 35000
6060 GOSUB 42000
6070 LI=0
6080 VPRINT LR(LI)*80,CR$
6090 IP=CINP(3)
6100 IP$=CHR$(IP)
6110 IF IP$="M" THEN 4080:REM MAIN MENU
6120 IF IP$="D" THEN 6160:REM STEP DOWN 
6130 IF IP$="U" THEN 6200:REM STEP UP 
6140 IF IP$="V" THEN 6240:REM VARY 
6150 GOTO 6090
6160 IF LI>=9 THEN LI=9:GOTO 6090
6170 VPRINT LR(LI)*80," "
6180 LI=LI+1
6190 GOTO 6080
6200 IF LI<=0 THEN LI=0:GOTO 6090
6210 VPRINT LR(LI)*80," "
6220 LI=LI-1
6230 GOTO 6080
6240 GOSUB 42000:GOSUB 41000:GOTO 6080
7000 REM PRINT A SOUND 
7010 GOSUB 30000
7020 GOSUB 39000
7030 SN=RV
7040 IF N$(SN)="" THEN VPRINT 119,"SOUND NOT ON FILE":GOTO 7020
7050 GOSUB 35000
7060 LPRINT 
7070 FOR I=0 TO 23
7080 FOR J=0 TO 78
7090 D=PEEK(VA+80*I+J)
7100 IF D>127 THEN D=64
7110 LPRINT CHR$(D);
7120 NEXT J
7130 LPRINT 
7140 NEXT I
7150 LPRINT :LPRINT 
7160 LPRINT "REGISTER NAME";TAB(40);"PORT";TAB(50);"VALUE":LPRINT 
7170 F=D(0,SN):GOSUB 36000
7180 LPRINT RN$(0);TAB(42);"0";TAB(51);FT
7190 LPRINT RN$(1);TAB(42);"1";TAB(51);CT
7200 F=D(1,SN):GOSUB 36000
7210 LPRINT RN$(2);TAB(42);"2";TAB(51);FT
7220 LPRINT RN$(3),TAB(42);"3";TAB(51);CT
7230 F=D(2,SN):GOSUB 36000
7240 LPRINT RN$(4);TAB(42);"4";TAB(51);FT
7250 LPRINT RN$(5);TAB(42);"5";TAB(51);CT
7260 F=D(3,SN):GOSUB 37000
7270 LPRINT RN$(6);TAB(42);"6";TAB(51);NP
7280 LPRINT RN$(7);TAB(42);"7";TAB(51);63-D(9,SN)
7290 LPRINT RN$(8);TAB(42);"8";TAB(51);D(4,SN)
7300 LPRINT RN$(9);TAB(42);"9";TAB(51);D(5,SN)
7310 LPRINT RN$(10);TAB(41);"10";TAB(51);D(6,SN)
7320 F=D(7,SN):GOSUB 38000
7330 LPRINT RN$(11);TAB(41);"11";TAB(51);FT
7340 LPRINT RN$(12);TAB(41);"12";TAB(51);CT
7350 LPRINT RN$(13);TAB(41);"13";TAB(51);D(8,SN)
7360 LPRINT :LPRINT :LPRINT 
7370 GOTO 1000
8000 REM CHANGE SOUND NAME 
8010 GOSUB 30000
8020 GOSUB 39000
8030 SN=RV
8040 IF N$(SN)="" THEN VPRINT 119,"SOUND NOT ON FILE":GOTO 8020
8050 GOSUB 35000
8060 VINPUT 40,"NEW SOUND NAME"; LINE N$(SN)
8070 GOTO 1000
9000 REM SAVE SOUND ON DISK
9010 GOSUB 30000
9020 GOSUB 39000
9030 SN=RV
9040 IF N$(SN)="" THEN VPRINT 119,"SOUND NOT ON FILE":GOTO 9020
9050 GOSUB 35000
9060 VINPUT 40,"FILE NAME"; LINE FI$
9070 CREATE 0;FI$
9080 DPRINT 0;N$(SN)
9090 FOR I=0 TO 9
9100 DPRINT 0;D(I,SN)
9110 NEXT I
9120 CLOSE 0
9130 GOTO 1000
10000 REM LOAD SAVED SOUND
10010 GOSUB 30000
10020 GOSUB 39000
10030 SN=RV
10040 IF ( NOT (N$(SN)="")) THEN VPRINT 119,"SOUND ALREADY EXISTS":GOTO 10020
10050 VINPUT 40,"FILE NAME"; LINE FI$
10060 OPEN 0;FI$
10070 DINPUT 0; LINE N$(SN)
10080 FOR I=0 TO 9
10090 DINPUT 0;D(I,SN)
10100 NEXT I
10110 CLOSE 0
10120 GOTO 1000
11000 REM PRINT DISK DIRECTORY
11010 FILL 32:PRINT 
11020 DIR 
11030 VINPUT 23*80,"PRESS 'RETURN'";, LINE A$
11040 GOTO 1000
12000 REM MODIFY VARIABLE LIMITS 
12010 FILL 32:PRINT 
12020 INPUT "TONE HIGH LIMIT (30-125000)";IP:IF IP<>0 THEN TH=IP
12030 IF TH<30 THEN PRINT "TOO LOW":GOTO 12020
12040 IF TH>125000 THEN PRINT "TOO HIGH":GOTO 12020
12050 INPUT "TONE LOW LIMIT (30-125000)";IP:IF IP<>0 THEN TL=IP
12060 IF TL<30 THEN PRINT "TOO LOW":GOTO 12050
12070 IF TL>TH THEN PRINT "TOO HIGH":GOTO 12050
12080 INPUT "ENVELOPE HIGH LIMIT (.0001-8)";IP:IF IP<>0 THEN EH=IP
12090 IF EH<.0001 THEN PRINT "TOO LOW":GOTO 12080
12100 IF EH>8 THEN PRINT "TOO HIGH":GOTO 12080
12110 INPUT "ENVELOPE LOW LIMIT (.0001-8)";IP:IF IP<>0 THEN EL=IP
12120 IF EL<.0001 THEN PRINT "TOO LOW":GOTO 12110
12130 IF EL>EH THEN PRINT "TOO HIGH":GOTO 12110
12140 INPUT "NOISE HIGH LIMIT (0-31)";IP:IF IP<>0 THEN NH=IP
12150 IF NH<0 THEN PRINT "TOO LOW":GOTO 12140
12160 IF NH>31 THEN PRINT "TOO HIGH"; GOTO 12140
12170 INPUT "NOISE LOW LIMIT (0-31)";IP:IF IP<>0 THEN NL=IP
12180 IF NL<0 THEN PRINT "TOO LOW"; GOTO 12170
12190 IF NL>NH THEN PRINT "TOO HIGH":GOTO 12170
12200 GOTO 1000
13000 REM EXIT PROGRAM 
13010 END 
30000 REM CONTROL DISPLAY 
30010 FILL 32
30020 VPRINT 0,"V=VARY, RETURN=LATCH"
30030 VPRINT 40,"SOUND:"
30040 VPRINT 80,"U=STEP UP"
30050 VPRINT 160,"D=STEP DOWN"
30060 VPRINT 240,"M=MAIN MENU"
30070 VPRINT 400,"TONES:";TL;TH;
30080 VPRINT 481,"A-"
30090 VPRINT 561,"B-"
30100 VPRINT 641,"C-"
30110 VPRINT 800,"NOISE:";NL;NH
30120 VPRINT 1040,"AMPLITUDE: (0-15)"
30130 VPRINT 1121,"A-"
30140 VPRINT 1201,"B-"
30150 VPRINT 1281,"C-"
30160 VPRINT 1440,"ENVELOPE:";EL;EH
30170 VPRINT 1601,"SHAPE: CONTINUE=   ATTACK=   ALTERNATE=   HOLD="
30180 VPRINT 1760,"CHANNEL ENABLE:"
30190 VPRINT 1848,"NOISE: C=   B=   A=     TONE: C=   B=   A="
30200 RETURN 
31000 REM READ SWITCH BOX
31010 REM JS=PSEUDO JOYSTICK POSITION
31020 REM RL=LOWEST VALUE IN RANGE 
31030 REM RH=HIGHEST VALUE IN RANGE 
31040 REM RETURN RV=VALUE IN DEFINED RANGE 
31050 REM ACCEPT "<" OR "," FOR DECREASE
31060 REM ACCEPT ">" OR "." FOR INCREASE
31070 REM ACCEPT 1-9 FOR SET POSITION
31080 REM ACCEPT RETURN AS TERMINATOR
31090 RI=CINP(3)
31100 IP=RI
31110 IF RI=13 THEN 31160
31120 IF RI>&39 OR RI<&31 THEN 31140
31130 JS=(RI-&30)*20:GOTO 31180
31140 IF RI=&3C OR RI=&2C THEN JS=JS-1
31150 IF RI=&3E OR RI=&2E THEN JS=JS+1
31160 IF JS<0 THEN JS=0
31170 IF JS>199 THEN JS=199
31180 RV=JS*((RH-RL)/199)+RL
31190 RETURN 
32000 REM PLOT LINE FOR DISPLAY OF VALUE 
32010 REM RL=LOW LIMIT, RH=HIGH LIMIT 
32020 REM RV=ACTUAL VALUE, LN=LINE NUMBER 
32030 IF RV>RH THEN RV=RH
32040 IF RV<RL THEN RV=RL
32050 Y=(23-LN)*3+1
32060 X2=(RH-RL)/120
32070 X2=INT((RV-RL)/X2+39.5)
32080 VPRINT LN*80+4,SPC(76)
32090 VPRINT LN*80+4,RV
32100 DRAW 39,Y,X2,Y,1
32110 RETURN 
32120 VPRINT LN*80+4,"ENVELOPE";SPC(68)
32130 RETURN 
33000 REM PLOT ENVELOPE SHAPE 
33010 REM INPUT RV, LOW 4 BITS DESCRIBE SHAPE 
33020 LN=20
33030 BT=8:LL=17:GOSUB 33070
33040 BT=4:LL=27:GOSUB 33070
33050 BT=2:LL=40:GOSUB 33070
33060 BT=1:LL=48
33070 IF (RV AND BT) THEN VPRINT LN*80+LL,"*" ELSE VPRINT LN*80+LL," "
33080 RETURN 
34000 REM PLOT CHANNEL ENABLE 
34010 REM INPUT RV, LOW 6 BITS CONTROL CHANNELS 
34020 LN=23
34030 BT=32:LL=17:GOSUB 33070
34040 BT=16:LL=22:GOSUB 33070
34050 BT=8:LL=27:GOSUB 33070
34060 BT=4:LL=40:GOSUB 33070
34070 BT=2:LL=45:GOSUB 33070
34080 BT=1:LL=50:GOTO 33070
35000 REM DISPLAY DATA FOR SOUND NUMBER SN 
35010 RL=TL:RH=TH
35020 RV=D(0,SN)
35030 LN=6:GOSUB 32000
35040 RV=D(1,SN)
35050 LN=7:GOSUB 32000
35060 RV=D(2,SN)
35070 LN=8:GOSUB 32000
35080 RL=NL:RH=NH
35090 RV=D(3,SN)
35100 LN=11:GOSUB 32000
35110 RL=0:RH=15
35120 RV=D(4,SN)
35130 LN=14:IF RV=16 THEN GOSUB 32120 ELSE GOSUB 32000
35140 RV=D(5,SN)
35150 LN=15:IF RV=16 THEN GOSUB 32120 ELSE GOSUB 32000
35160 RV=D(6,SN)
35170 LN=16:IF RV=16 THEN GOSUB 32120 ELSE GOSUB 32000
35180 RL=EL:RH=EH
35190 RV=D(7,SN)
35200 LN=19:GOSUB 32000
35210 RV=D(8,SN)
35220 GOSUB 33000
35230 RV=D(9,SN)
35240 GOTO 34000
36000 REM COMPUTE REGISTER VALUES FOR TONE FREQUENCY 
36010 IF F=0 THEN CT=0:FT=0:RETURN 
36020 TP=(2000000/(16*F))
36030 IF TP>4095 THEN TP=4095
36040 CT=INT(TP/256)
36050 FT=INT(TP-256*CT)
36060 RETURN 
37000 REM COMPUTE REGISTER VALUES FOR NOISE FREQUENCY 
37010 NP=F
37020 RETURN 
38000 REM COMPUTE REGISTER VALUES FOR ENVELOPE PERIOD 
38010 IF F=0 THEN CT=0:FT=0:RETURN 
38020 F=1/F
38030 EP=(2000000/F)/256
38040 CT=INT(EP/256)
38050 FT=INT(EP-256*CT)
38060 RETURN 
39000 REM INPUT SCREEN SELECTION
39010 VINPUT 40,"(ENTER SOUND NUMBER) ";,RV
39020 VPRINT 40,SPC(40)
39030 RV=ABS(INT(RV)):IF RV>19 THEN 39010
39040 VPRINT 40,RV
39050 VPRINT 44,N$(RV)
39060 RETURN 
40000 REM VARY SELECTED INPUT ON LINE LN
40010 VPRINT LR(LI)*80,">"
40020 LN=LR(LI):IP=0
40030 IF LI<3 THEN RL=TL:RH=TH
40040 IF LI=3 THEN RL=NL:RH=NH
40050 IF LI>3 AND LI<7 THEN RL=0:RH=16
40060 IF LI=7 THEN RL=EL:RH=EH
40070 IF LI=8 THEN RL=0:RH=3:BT=0
40080 IF LI=9 THEN RL=0:RH=5:BT=0
40090 IF LI<8 THEN JS=(D(LI,SN)-RL)/((RH-RL)/199) ELSE JS=0
40100 IF IP=13 THEN RETURN 
40110 ON LI GOTO 40120,40120,40120,40140,40140,40140,40170,40180,40300
40120 GOSUB 31000:RV=INT(RV)
40130 GOSUB 32000:D(LI,SN)=RV:GOTO 40100
40140 GOSUB 31000:RV=INT(RV+.5):IF RV<>16 THEN GOTO 40130
40150 VPRINT LN*80+4,"ENVELOPE";SPC(68)
40160 D(LI,SN)=RV:GOTO 40100
40170 GOSUB 31000:GOTO 40130
40180 GOSUB 31000
40190 VPRINT 20*80+BS(3-BT)+1," "
40200 BT=3-INT(RV+.5)
40210 VPRINT 20*80+BS(3-BT)+1,CR$
40220 IF IP<>13 THEN 40180
40230 VPRINT 20*80+BS(3-BT)+1," "
40240 DV=INT(2^BT)
40250 IF (D(8,SN) AND DV) THEN 40280
40260 D(8,SN)=D(8,SN)+DV
40270 RV=D(8,SN):GOSUB 33000:RETURN 
40280 D(8,SN)=D(8,SN)-DV
40290 GOTO 40270
40300 GOSUB 31000
40310 VPRINT 23*80+BC(5-BT)+1," "
40320 BT=5-INT(RV+.5)
40330 VPRINT 23*80+BC(5-BT)+1,"<"
40340 IF IP<>13 THEN 40300
40350 VPRINT 23*80+BC(5-BT)+1," "
40360 DV=INT(2^BT)
40370 IF (D(9,SN) AND DV) THEN 40400
40380 D(9,SN)=D(9,SN)+DV
40390 RV=D(9,SN):GOSUB 34000:RETURN 
40400 D(9,SN)=D(9,SN)-DV
40410 GOTO 40390
41000 REM DYNAMICALLY VARY SELECTED INPUT ON LINE LN
41010 VPRINT LR(LI)*80,">"
41020 LN=LR(LI):IP=0
41030 IF LI<3 THEN RL=TL:RH=TH
41040 IF LI=3 THEN RL=NL:RH=NH
41050 IF LI>3 AND LI<7 THEN RL=0:RH=16
41060 IF LI=7 THEN RL=EL:RH=EH
41070 IF LI=8 THEN RL=0:RH=3:BT=0
41080 IF LI=9 THEN RL=0:RH=5:BT=0
41090 IF LI<8 THEN JS=(D(LI,SN)-RL)/((RH-RL)/199) ELSE JS=0
41100 IF IP=13 THEN RETURN 
41110 ON LI GOTO 41120,41120,41170,41240,41240,41240,41270,41330,41450
41120 GOSUB 31000:RV=INT(RV):GOSUB 32000
41130 D(LI,SN)=RV:F=RV:GOSUB 36000
41140 OUT PR,LI*2:OUT PD,FT
41150 OUT PR,LI*2+1:OUT PD,CT
41160 GOTO 41100
41170 GOSUB 31000
41180 RV=INT(RV)
41190 GOSUB 32000
41200 F=RV
41210 GOSUB 37000:D(3,SN)=F
41220 OUT PR,6:OUT PD,NP
41230 GOTO 41100
41240 GOSUB 31000:RV=INT(RV+.5):OUT PR,LI+4:OUT PD,RV:D(LI,SN)=RV:IF RV<>16 THEN GOSUB 32000:GOTO 41100
41250 VPRINT LN*80+4,"ENVELOPE";SPC(68)
41260 GOTO 41100
41270 GOSUB 31000:GOSUB 32000
41280 D(LI,SN)=RV
41290 F=RV:GOSUB 38000
41300 OUT PR,11:OUT PD,FT
41310 OUT PR,12:OUT PD,CT
41320 GOTO 41100
41330 GOSUB 31000
41340 VPRINT 20*80+BS(3-BT)+1," "
41350 BT=3-INT(RV+.5)
41360 VPRINT 20*80+BS(3-BT)+1,"<"
41370 IF IP<>13 THEN 41330
41380 VPRINT 20*80+BS(3-BT)+1," "
41390 DV=INT(2^BT)
41400 IF (D(8,SN) AND DV) THEN 41430
41410 D(8,SN)=D(8,SN)+DV
41420 RV=D(8,SN):GOSUB 33000:OUT PR,13:OUT PD,RV:RETURN 
41430 D(8,SN)=D(8,SN)-DV
41440 GOTO 41420
41450 GOSUB 31000
41460 VPRINT 23*80+BC(5-BT)+1," "
41470 BT=5-INT(RV+.5)
41480 VPRINT 23*80+BC(5-BT)+1,"<"
41490 IF IP<>13 THEN 41450
41500 VPRINT 23*80+BC(5-BT)+1," "
41510 DV=INT(2^BT)
41520 IF (D(9,SN) AND DV) THEN 41550
41530 D(9,SN)=D(9,SN)+DV
41540 RV=D(9,SN):GOSUB 34000:OUT PR,7:OUT PD,255-RV:RETURN 
41550 D(9,SN)=D(9,SN)-DV
41560 GOTO 41540
42000 REM WRITE CURRENT SOUND TO CONTROL PORTS
42010 FOR I=0 TO 13
42020 OUT PR,I:OUT PD,0
42030 NEXT I
42040 F=D(0,SN):GOSUB 36000
42050 OUT PR,0:OUT PD,FT
42060 OUT PR,1:OUT PD,CT
42070 F=D(1,SN):GOSUB 36000
42080 OUT PR,2:OUT PD,FT
42090 OUT PR,3:OUT PD,CT
42100 F=D(2,SN):GOSUB 36000
42110 OUT PR,4:OUT PD,FT
42120 OUT PR,5:OUT PD,CT
42130 F=D(3,SN):GOSUB 37000
42140 OUT PR,6:OUT PD,NP
42150 OUT PR,7:OUT PD,255-D(9,SN)
42160 OUT PR,8:OUT PD,D(4,SN)
42170 OUT PR,9:OUT PD,D(5,SN)
42180 OUT PR,10:OUT PD,D(6,SN)
42190 F=D(7,SN):GOSUB 38000
42200 OUT PR,11:OUT PD,FT
42210 OUT PR,12:OUT PD,CT
42220 OUT PR,13:OUT PD,D(8,SN)
42230 RETURN 
43000 REM PRINT INSTRUCTIONS
43010 FILL 32
43020 RESTORE 43080
43030 FOR I=0 TO 20
43040 READ A$
43050 VPRINT I*80,A$
43060 NEXT 
43070 RETURN 
43080 DATA "           ***  HAWKEYE GRAFIX SOUND GENERATION PROGRAM  ***"
43090 DATA ""
43100 DATA " This program is designed for use in the development of sound effects with the"
43110 DATA "General Instruments AY-3-8910/8912 sound generator chips, addressed at port"
43120 DATA "128 for register select, and 129 for data."
43130 DATA ""
43140 DATA " In the menu mode, press the key indicated to execute the function desired."
43150 DATA ""
43160 DATA " In the define, modify, or experiment modes, the keys operate in the following"
43170 DATA "manner:"
43180 DATA ""
43190 DATA "     Pressing the 'U' key will move the selection cursor up."
43200 DATA "     Pressing the 'D' key will move the selection cursor down."
43210 DATA "     Pressing the 'M' key will return to the main