     $F259/62041:   Initialise disk controller

    Jump from $EBC2:

    F259: A9 6F     LDA #$6F        ; bit 4 (write prot) & 7 (SYNC)
    F25B: 8D 02 1C  STA $1C02       ; data direction register port B
    F25E: 29 F0     AND #$F0
    F260: 8D 00 1C  STA $1C00       ; port B, control port
    F263: AD 0C 1C  LDA $1C0C       ; PCR, control register
    F266: 29 FE     AND #$FE
    F268: 09 0E     ORA #$0E
    F26A: 09 E0     ORA #$E0
    F26C: 8D 0C 1C  STA $1C0C
    F26F: A9 41     LDA #$41
    F271: 8D 0B 1C  STA $1C0B       ; timer 1 free running, enable
    F274: A9 00     LDA #$00        ; port A latch
    F276: 8D 06 1C  STA $1C06       ; timer 1 lo latch
    F279: A9 3A     LDA #$3A
    F27B: 8D 07 1C  STA $1C07       ; timer 1 hi latch
    F27E: 8D 05 1C  STA $1C05       ; timer 1 hi
    F281: A9 7F     LDA #$7F
    F283: 8D 0E 1C  STA $1C0E       ; erase IRQs
    F286: A9 C0     LDA #$C0
    F288: 8D 0D 1C  STA $1C0D
    F28B: 8D 0E 1C  STA $1C0E       ; IER, allow interrupts
    F28E: A9 FF     LDA #$FF
    F290: 85 3E     STA $3E
    F292: 85 51     STA $51         ; track counter for formatting
    F294: A9 08     LDA #$08        ; 8
    F296: 85 39     STA $39         ; constants for block header
    F298: A9 07     LDA #$07        ; 7
    F29A: 85 47     STA $47         ; constants for data block
    F29C: A9 05     LDA #$05
    F29E: 85 62     STA $62
    F2A0: A9 FA     LDA #$FA        ; pointer $62/$63 to $FA05
    F2A2: 85 63     STA $63
    F2A4: A9 C8     LDA #$C8        ; 200
    F2A6: 85 64     STA $64
    F2A8: A9 04     LDA #$04
    F2AA: 85 5E     STA $5E
    F2AC: A9 04     LDA #$04
    F2AE: 85 5F     STA $5F

        Previous Page / Next Page