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- .define Sbi4
- .sect .text
- .sect .rom
- .sect .data
- .sect .bss
- .sect .text
- ! This subroutine subtracts two fourbyte signed integers.
- Sbi4:
- jsr Addsub ! initiate addresses
- sec
- 1: lda (ADDR+2),y ! get lowbyte+y first operand
- sbc (ADDR),y ! subtract lowbyte+y second operand
- sta (ADDR+2),y ! put on stack lowbyte+y result
- iny
- inx
- bne 1b
- rts
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