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- .define Teq
- .sect .text
- .sect .rom
- .sect .data
- .sect .bss
- .sect .text
- ! This subroutine test if the value in registerpair AX is zero
- ! or nonzero.
- ! The returned value, a 1 or a 0, is in AX.
- Teq:
- tay
- beq 1f ! A is zero
- 2: lda #0 ! AX is zero
- tax
- rts
- 1: txa
- bne 2b ! X is zero
- lda #0 ! AX is nonzero
- ldx #1
- rts
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