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Fixed the Creativision library's bios_playsound().

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It was disabling interrupts permanently.
This commit is contained in:
Greg King 2021-05-14 19:12:59 -04:00
parent 31128d4809
commit f636d4e634
1 changed files with 40 additions and 36 deletions
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76
libsrc/creativision/psg.s
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@ -1,63 +1,67 @@
; void __fastcall__ psg_outb (unsigned char b);
; void __fastcall__ psg_delay (unsigned char c);
; void __fastcall__ bios_playsound (const void *b, unsigned char c);
; void __fastcall__ psg_delay (unsigned char b);
; void __fastcall__ bios_playsound (void *a, unsigned char b);
; void psg_silence (void);
.export _psg_outb, _psg_silence, _psg_delay
.export _bios_playsound
.import popa
.export _psg_outb, _psg_silence, _psg_delay
.export _bios_playsound
.import popax
.include "creativision.inc"
_psg_outb:
;* Let BIOS output the value
jmp $FE77
songptr := $00 ; Points to current tune data
volptr := $04 ; Points to current volume table
_psg_outb:
;* Let BIOS output the value.
jmp $FE77
_psg_silence:
jmp $FE54
jmp $FE54
_psg_delay:
tay
l1: lda #200
l2: sbc #1
bne l2
l1: lda #200
l2: sbc #1
bne l2
lda #200
l3: sbc #1
bne l3
lda #200
l3: sbc #1
bne l3
dey
bne l1
bne l1
rts
;* Creativision Sound Player
;* Based on BIOS song player.
;*
;* Based on BIOS sound player.
;* Pass a pointer to a set of note triples, terminated with a tempo byte
;* and the len (max 255)
;* Pass a pointer to a set of note triples, terminated with a tempo byte;
;* and pass the length of the triples and tempo (max 255).
;*
;* Note: tune data must be stored backwards.
_bios_playsound:
pha ; Save Length Byte
php
pha ; Save tune length
sei
lda #$D5 ; BIOS volume table low
sta $4
lda #$FC ; BIOS volume table high
sta $5
lda #<$FCD5 ; A BIOS volume table
ldx #>$FCD5
sta volptr
stx volptr+1
jsr popa ; Get Sound table pointer low
sta $0
jsr popa ; Get Sound table pointer high
sta $1
jsr popax ; Get tune array pointer
sta songptr
stx songptr+1
pla
tay ; Put length in Y
dey
php
jmp $FBED ; Let BIOS do it's thing
tay
dey ; Point to tempo byte
jmp $FBED ; Let BIOS do its thing