1984-12-17 11:03:13 +00:00
|
|
|
.define Ngi2
|
1987-01-30 18:41:42 +00:00
|
|
|
.sect .text
|
|
|
|
.sect .rom
|
|
|
|
.sect .data
|
|
|
|
.sect .bss
|
|
|
|
.sect .text
|
1984-12-17 11:03:13 +00:00
|
|
|
|
|
|
|
! This subroutine negates the integer in registerpair AX.
|
|
|
|
! The negation is a one's complement plus one.
|
|
|
|
|
|
|
|
|
|
|
|
Ngi2:
|
1988-08-19 17:05:03 +00:00
|
|
|
eor #0x0FF ! one's complement A
|
1984-12-17 11:03:13 +00:00
|
|
|
tay
|
|
|
|
txa
|
1988-08-19 17:05:03 +00:00
|
|
|
eor #0x0FF ! one's complement X
|
1984-12-17 11:03:13 +00:00
|
|
|
tax
|
|
|
|
inx ! increment X
|
|
|
|
bne 1f
|
|
|
|
iny ! increment A if neccesairy
|
|
|
|
1: tya
|
|
|
|
rts
|
|
|
|
|
|
|
|
|