20 *= $600
30 PLA PULL OFF DUMMY ARG COUNT
40 LDA #$08
50 STA $D01F INIT SWITCHES
60 M1 LDA $D01F GET VALUE
70 AND #$01 ?START PRESSED
80 BNE M1 NOT YES
90 LDY #$FF DELAY
0100 M2 LDX #$FF SOME
0110 JSR DEL GO LOOP
0120 DEY
0130 BNE M2
0140 LDA #$08 RESET
0150 STA $D01F START SWITCH
0160 LDX 208 GET PARM
0170 CPX #0 ?PLAYBACK
0180 BNE NP NO
0190 JMP PB GO PLAY BACK SOUND
0200 NP LDA #0
0210 STA $D400 KILL DMA
0220 STA $D40E KILL VBI
0230 MD STA $D40A WSYNC
0240 STA $D40A WSYNC
0250 DONE LDX 207
0260 JSR DEL GO WAIT IF NEED BE
0270 LDA $D204 GET INPUT BYTE
0280 GO LDX #$13
0290 STX $D20F TURN OFF FAST SCAN
0300 LDX #$17
0310 STX $D40A WSYNC
0320 STX $D20F SAY FAST POT SCAN
0330 STX $D20B START SCAN
0340 LDX FLAG
0350 CPX #0 ?LEFT HALF OF BYTE
0360 BNE RT NO
0370 AND #$F0
0380 STA BYTE SAVE IT
0390 ROR A
0400 ROR A
0410 ROR A
0420 ROR A
0430 AND #$0F
0440 ORA #$10 SAY USE 4 BIT D/A
0450 STA $D201 ECHO TO SPEAKER
0460 INC FLAG SAY RIGHT NEXT
0470 JMP MD
0480 RT ROR A
0490 ROR A
0500 ROR A
0510 ROR A
0520 AND #$0F
0530 ORA #$10 SAY USE 4 BIT D/A
0540 STA $D201 SAY SOMETHING
0550 AND #$0F REMOVE TOP 4 BITS
0560 ORA BYTE ADD IN LEFT NIBBLE
0570 DEC FLAG SAY LEFT NEXT
0580 LDY #0
0590 STA (205),Y SAVE TO BYTE
0600 LDA $D01F
0610 AND #$01 ?START KEY
0620 BEQ FINI YES
0630 D3 INC 205 INCREMENT
0640 BNE MD BUFFER
0650 INC 206 AREA
0660 LDX 206 POINTER
0670 CPX 209 ?END OF MEMORY
0680 BNE MD NO CONTINUE
0690 JMP FINI GO FINISH THINGS
0700 DEL DEX
0710 BNE DEL
0720 RTS
0730 FINI LDA 208 ?TALK A LOT
0740 CMP #2 ?HUH
0750 BNE FINI1 NO, JUST RETURN
0760 LDA #0 RESET
0770 STA 205 BUFFER
0780 LDA #64 START
0790 STA 206 POINTERS
0800 JMP NP AND DO IT AGAIN
0810 FINI1 LDA #$40
0820 STA $D40E RESTART VBI'S
0830 LDA #$22 AND SCREEN DMA
0840 STA $D400
0850 RTS
0860 PB LDA #0
0870 STA $D40E KILL VBI
0880 STA $D400 KILL DMA
0890 PB1 LDX 207 GET DELAY COUNT
0900 JSR DEL
0910 LDY #0
0920 LDA (203),Y GET SOME DATA
0930 TAX
0940 ROR A
0950 ROR A
0960 ROR A
0970 ROR A
0980 AND #$0F GET LEFT NIBBLE
0990 ORA #$10 SAY USE D/A
1000 STA $D201 STORE THE VALUE
1010 TXA
1020 AND #$0F
1030 ORA #$10
1040 CLC
1050 CLC
1060 CLC
1070 CLC
1080 LDX 207 GET DELAY VALUE
1090 JSR DEL
1100 STA $D201 MAKE SOME NOISE
1110 D4 INC 203 INCREMENT
1120 BNE PB
1130 INC 204 BUFFER
1140 LDX 204
1150 CPX 206 POINTERA
1160 BNE PB1
1170 JMP FINI
1180 BYTE .BYTE 0
1190 FLAG .BYTE 0
PROGRAM LISTING: 83-07/TALK.ASM