You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

27 lines
280 B
ArmAsm

;
; Ullrich von Bassewitz, 29.12.1999
;
; CC65 runtime: Decrement eax by value in Y
;
.export deceaxy
.importzp sreg, tmp1
deceaxy:
sty tmp1
sec
sbc tmp1
sta tmp1
txa
sbc #0
tax
lda sreg
sbc #0
sta sreg
lda sreg+1
sbc #0
sta sreg+1
lda tmp1
rts