18 lines
293 B
ArmAsm
18 lines
293 B
ArmAsm
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.define Sbi4
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! This subroutine subtracts two fourbyte signed integers.
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Sbi4:
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jsr Addsub ! initiate addresses
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sec
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1: lda (ADDR+2),y ! get lowbyte+y first operand
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sbc (ADDR),y ! subtract lowbyte+y second operand
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sta (ADDR+2),y ! put on stack lowbyte+y result
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iny
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inx
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bne 1b
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rts
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