nes-proj/cpu/6502/sys/lc-asm.S

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ArmAsm
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;---------------------------------------------------------------------
.importzp ptr1
.export _lc_set
.export _lc_resume
;---------------------------------------------------------------------
_lc_set:
sta ptr1
stx ptr1+1
tsx
lda $0102,x
ldy #$01
sta (ptr1),y
lda $0101,x
dey
sta (ptr1),y
rts
;---------------------------------------------------------------------
_lc_resume:
sta ptr1
stx ptr1+1
ldy #$01
lda (ptr1),y
beq :+
tsx
sta $0102,x
dey
lda (ptr1),y
sta $0101,x
: rts
;---------------------------------------------------------------------