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Please consider updating player program listing in wiki

SteveGuidi opened this issue · comments

commented

The player program listing from the "Anleitung zur SID‐Karte" wiki page has a couple of problems:

  • Memory addresses for op codes bytes and assembly instruction are ambiguous (Interrupt-Routine)
. 3038  20 cd cd  jsr $cecd   ;TED-Sound bearbeiten
. 303b  4c be fc  jmp $fcc3   ;Interrupt beenden (2)

The correct address is the one listed in the assembly instruction, not the op code. Note: The original PDF documentation for the SidCard project has the same error.

  • Missing Y register for memory offset in the STA instruction (Musik Beenden)
. 3084  99 40 fd  sta $fd40,  ;...löschen =

This should read sta $fd40,y

Finally, the player program distributed with the SidCard d64 disks is slightly different and corrects a couple of music play/stop issues. Perhaps you can add it to the wiki, or note that code on the current page is a copy of the original documentation (with errors) and has since been updated.

Here is a listing of the updated player subroutines:

Music initialization

. 3000 a9 00     lda #$00
. 3002 78        sei
. 3003 8d 3f ff  sta $ff3f
. 3006 20 00 10  jsr $1000
. 3009 a9 18     lda #$18
. 300b a0 30     ldy #$30
. 300d 8d 14 03  sta $0314
. 3010 8c 15 03  sty $0315
. 3013 8d 3e ff  sta $ff3e
. 3016 58        cli
. 3017 60        rts

Interrupt routine (music playback)

. 3018 ad 09 ff  lda $ff09
. 301b 8d 09 ff  sta $ff09
. 301e 8d 3f ff  sta $ff3f
. 3021 20 03 10  jsr $1003
. 3024 a0 18     ldy #$18
. 3026 b9 00 d4  lda $d400,y
. 3029 99 40 fd  sta $fd40,y
. 302c 88        dey
. 302d 10 f7     bpl $3026
. 302f 8d 3e ff  sta $ff3e
. 3032 20 bf cf  jsr $cfbf
. 3035 20 cd ce  jsr $cecd
. 3038 20 11 db  jsr $db11
. 303b 4c be fc  jmp $fcbe

Stop playback

. 3070 78        sei
. 3071 a9 0e     lda #$0e
. 3073 a0 ce     ldy #$ce
. 3075 8d 14 03  sta $0314
. 3078 8c 15 03  sty $0315
. 307b 58        cli
. 307c a0 18     ldy #$18
. 307e a9 00     lda #$00
. 3080 99 40 fd  sta $fd40,y
. 3083 88        dey
. 3084 10 fa     bpl $3080
. 3086 60        rts
commented

Hi @SteveGuidi, thanks a lot for your corrections! I have removed editing restrictions from the wiki, could you please apply the modifications yourself? I'm afraid I would still miss something!

This was still a work in progress BTW, when I have time I would like to translate the docs to English, but I guess it'd be better to do that once everything looks correct!

commented

Great job, thanks a lot!