mirror of
https://github.com/nathanriggs/AppleIIAsm-Collection.git
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39 lines
641 B
Plaintext
39 lines
641 B
Plaintext
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*
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COMP16
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*
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PLA
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STA RETADR
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PLA
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STA RETADR+1
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PLA
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STA :SUBT
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PLA
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STA :SUBT+1
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PLA
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STA :MINU
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PLA
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STA :MINU+1
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LDA RETADR+1
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PHA
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LDA RETADR
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PHA
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LDA :MINU
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CMP :SUBT
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BEQ :EQUAL
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LDA :MINU+1
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SBC :SUBT+1
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ORA #1
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BVS :OVFLOW
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RTS
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:EQUAL
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LDA :MINU+1
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SBC :SUBT+1
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BVS :OVFLOW
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RTS
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:OVFLOW
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EOR #$80
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ORA #1
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RTS
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:MINU DS 2
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:SUBT DS 2
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