$FDA3/64931:   Initialise I/O

Jump from $FCF2, $FE69, $FF84:

FDA3: A9 7F     LDA #$7F
FDA5: 8D 0D DC  STA $DC0D     ; CIA1: Interrupt (IRQ) Control Register
FDA8: 8D 0D DD  STA $DD0D     ; CIA2: Interrupt (NMI) Control Register
FDAB: 8D 00 DC  STA $DC00     ; CIA1: Data Port A (Keyboard, Joystick, Paddles)
FDAE: A9 08     LDA #$08
FDB0: 8D 0E DC  STA $DC0E     ; CIA1: Control Register A
FDB3: 8D 0E DD  STA $DD0E     ; CIA2: Control Register A
FDB6: 8D 0F DC  STA $DC0F     ; CIA1: Control Register B
FDB9: 8D 0F DD  STA $DD0F     ; CIA2: Control Register B
FDBC: A2 00     LDX #$00
FDBE: 8E 03 DC  STX $DC03     ; CIA1: Data Direction Register B
FDC1: 8E 03 DD  STX $DD03     ; CIA2: Data Direction Register B
FDC4: 8E 18 D4  STX $D418     ; SID: Select Filter Mode and Volume
FDC7: CA        DEX
FDC8: 8E 02 DC  STX $DC02     ; CIA1: Data Direction Register A
FDCB: A9 07     LDA #$07
FDCD: 8D 00 DD  STA $DD00     ; CIA2: Data Port A (Serial Bus, RS232, VIC Base Mem.)
FDD0: A9 3F     LDA #$3F
FDD2: 8D 02 DD  STA $DD02     ; CIA2: Data Direction Register A
FDD5: A9 E7     LDA #$E7
FDD7: 85 01     STA $01       ; 6510 On-chip 8-bit Input/Output Register
FDD9: A9 2F     LDA #$2F
FDDB: 85 00     STA $00       ; 6510 On-chip Data Direction Register

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