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