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cc65/libsrc/cbm610/pokesys.s

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ArmAsm
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;
; Ullrich von Bassewitz, 29.09.1998
;
; void pokebsys (unsigned Addr, unsigned char Val);
; void pokewsys (unsigned Addr, unsigned Val);
.export _pokebsys, _pokewsys
.import popsreg
.importzp sreg, tmp1
.include "zeropage.inc"
_pokebsys:
jsr popsreg ; Get the address
ldx IndReg
ldy #$0F
sty IndReg ; Switch to the system bank
ldy #$00
sta (sreg),y
stx IndReg
rts
_pokewsys:
stx tmp1 ; Save high byte
jsr popsreg ; Get the address
ldx IndReg
ldy #$0F
sty IndReg ; Switch to the system bank
ldy #$00
sta (sreg),y
iny
lda tmp1
sta (sreg),y
stx IndReg
rts