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- .define Exg2
- .sect .text
- .sect .rom
- .sect .data
- .sect .bss
- .sect .text
- ! This subroutine exchanges two words on top of the stack.
- ! The top word of the stack is really in the AX registerpair.
- ! So this word is exchanged with the top of the real stack.
- Exg2:
- pha ! save A
- txa
- pha ! save X
- jsr Pop ! get top real stack
- stx EXG
- sta EXG+1 ! save top of real stack
- pla ! get X
- tax
- pla ! get A
- jsr Push ! push on real stack
- ldx EXG ! get new X
- lda EXG+1 ! get new A
- rts
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