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Re: Unknown Apple II board: "FLY BD"



Ok, here's the assembly listing of the ROM.  I copied it by hand after
a few attempts to dump it to disk from Applesoft using the old "monitor
command" trick and by calling the LIST monitor routine directly.  Both
resulted in a partial listing and other garbage.  Odd, works when not
writing to a file.

Anyway, here it is, card in slot 7:

      PHA
      TXA
      PHA
      TYA
      PHA
      PHP
      SEI
      JSR $FF58
      TSX
      LDA $0100,X
      AND #$0F
      PLP
      TAY
      TSX
      PLA
      PLA
      PLA
      AND #$7F
      STA $0678,Y
      TXS
      TYA
      TAX
      ASL
      ASL
      ASL
      ASL
      TAY
      STA $05F8,X
      LDA #$FF
      STA $C083,Y
      LDA #$7F
      STA $C082.Y
      LDA #$CC
      STA $C08C,Y
      LDA #$00
      STA $C08B,Y
      STA $C08E,Y
      TXA
      TAY
      LDA $0678,Y
      CMP #$09
      BNE HERE0
      LDA #$55
      STA $06F8,Y
      LDA #$00
      STA $07F8,Y
HERE1 PLA
      TAY
      PLA
      TAX
      PLA
      RTS
HERE0 LDA $06F8,Y
      CMP #$55
      BEQ HERE2
      LDX $05F8,Y
      JSR $C800
      CLC
      BCC HERE1
HERE2 LDX $05F8,Y
      JSR $C803
      CLC
      BCC HERE1
      BRK

That's it.  I imagine the $c08c addresses and there abouts are
registers for the 6522?  I see a comparison to 9 which is the TAB
character.  Is this a printer driver of some kind?

Ron