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- .define TestFFh
- .sect .text
- .sect .rom
- .sect .data
- .sect .bss
- .sect .text
- ! This subroutine tests if the value on top of the stack is <= 256.
- ! It is used if the istruction argument is on top of the stack.
- ! The value is saved in Y.
- TestFFh:
- cmp #2
- bpl 1f ! value > 256
- cmp #0
- beq 2f
- cpx #0
- bne 1f ! value is zero
- 2: dex
- txa
- tay
- rts
- 1: ldx #Eoddz
- lda #0
- jsr Trap
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