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66 lines
568 B
NASM
66 lines
568 B
NASM
;MMC1 write handler
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.define R0 $9fff
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.define R1 $bfff
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.define R2 $dfff
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.define R3 $f000
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.section "MMC1" FREE
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WriteR0
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sta R0
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lsr A
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sta R0
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lsr A
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sta R0
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lsr A
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sta R0
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lsr A
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sta R0
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rts
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WriteR1
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sta R1
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lsr A
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sta R1
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lsr A
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sta R1
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lsr A
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sta R1
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lsr A
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sta R1
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rts
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WriteR2
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sta R2
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lsr A
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sta R2
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lsr A
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sta R2
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lsr A
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sta R2
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lsr A
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sta R2
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rts
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ProgramSwitch1
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sta BankLatch1
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ProgramSwitch2
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sta BankLatch2
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WriteR3
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tax
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lda M2000
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and #$7f
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sta $2000
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txa
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sta R3
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lsr A
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sta R3
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lsr A
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sta R3
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lsr A
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sta R3
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lsr A
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sta R3
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lda M2000
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sta $2000
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rts
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.ends |