Date: 2005-10-02 23:26:21
Hello floppy experts. I am looking for an explanation to the 1541 code snippet below. [... entering with X=0] TXA ; LDA #$00 LDY #$A2 ; 162 times? 324 GCR bytes probably... L75F: BVC * CLV EOR $1801 ; get the byte from parallel port STA $1C01 ; write to disk DEC $1800 ; acknowledge (DATA HI?) LDA $1801 BVC * CLV EOR $1801 ; zero out??! STA $1C01 INC $1800 ; acknowledge (DATA LO?) LDA $1801 DEY BNE L75F I am not sure if I am missing something very obvious but I just don't understand WTH is the EOR $1801 for and how come does LDA $xxxx EOR $xxxx not zero the A?? Please someone enlighten me on that... -- If your law requires a police state to enforce, your law is wrong. Message was sent through the cbm-hackers mailing list
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