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collapseos/arch/z80/sms/blk/626
Virgil Dupras 2b8524d11e sms: CPORT_CTL is write-only!
why did I think that I could read from it?
2020-11-08 08:43:24 -05:00

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CODE _TRB! HL POP, chkPS, ( B0 -> B6, B1 -> B2 )
L RR, RLA, RLA, RLA, RLA, L RR, RLA, RLA, RLA,
0x44 ANDi, L A LDrr, CPORT_MEM LDA(i),
0xbb ANDi, L ORr, CPORT_CTL OUTiA, CPORT_MEM LD(i)A,
;CODE
CODE _THB! HL POP, chkPS, ( B0 -> B7, B1 -> B3 )
L RR, RLA, RLA, RLA, RLA, L RR, RLA, RLA, RLA, RLA,
0x88 ANDi, L A LDrr, CPORT_MEM LDA(i),
0x77 ANDi, L ORr, CPORT_CTL OUTiA, CPORT_MEM LD(i)A,
;CODE
CODE _D1@ CPORT_D1 INAi, PUSHA, ;CODE
CODE _D2@ CPORT_D2 INAi, PUSHA, ;CODE