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44 lines
483 B
ArmAsm
44 lines
483 B
ArmAsm
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; four-digit base 5 increment
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inc_base5:
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inc NUMBER_LOW
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lda NUMBER_LOW
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and #$f
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cmp #5
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bne inc_base5_done
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clc
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lda NUMBER_LOW
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adc #$b
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sta NUMBER_LOW
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lda NUMBER_LOW
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cmp #$50
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bne inc_base5_done
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; if here, overflow to top byte
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lda #0
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sta NUMBER_LOW
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inc NUMBER_HIGH
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lda NUMBER_HIGH
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and #$f
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cmp #5
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bne inc_base5_done
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clc
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lda NUMBER_HIGH
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adc #$b
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sta NUMBER_HIGH
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lda NUMBER_HIGH
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cmp #$50
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bne inc_base5_done
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lda #$0
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sta NUMBER_HIGH
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inc_base5_done:
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rts
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