50 lines
822 B
NASM
50 lines
822 B
NASM
prog START 0
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+JSUB stackinit
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LDA #5
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+STA @stackptr
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JSUB stackpush
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LDA #6
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+STA @stackptr
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JSUB stackpush
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JSUB stackpop
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+LDA @stackptr
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JSUB stackpop
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+LDA @stackptr
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HALT J HALT
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END prog
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stackinit STA oldvalue
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CLEAR A
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LDA #stack
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STA stackptr
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CLEAR A
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LDA oldvalue
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RSUB
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stackpush STA oldvalue
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CLEAR A
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LDA stackptr
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ADD #3
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STA stackptr
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CLEAR A
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LDA oldvalue
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RSUB
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stackpop STA oldvalue
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CLEAR A
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LDA stackptr
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SUB #3
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STA stackptr
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CLEAR A
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LDA oldvalue
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RSUB
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oldvalue WORD 0
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stackptr WORD 0
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stack RESW 1000
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