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Document Title: [DefenderMap.html (html file)]

0000 - 9800 Video RAM
C000 - CFFF ROM (4 banks) + I/O
D000 - FFFF ROM

C000 - C00F Color Registers  (16 bytes of BBGGGRRR)

C3FC        WatchDog

C400 - C4FF CMOS RAM battery backed up

C800        6 bits of the video counters bits 2-7

CC00        PIA1_data a (widget = I/O board)

  bit 0  Auto Up
  bit 1  Advance
  bit 2  Right Coin
  bit 3  High Score Reset
  bit 4  Left Coin
  bit 5  Center Coin
  bit 6
  bit 7

CC01 PIA1_ctrl a

CC02 PIA1_data b

  bit 0 \
  bit 1 |
  bit 2 |-6 bits to sound board
  bit 3 |
  bit 4 |
  bit 5 /
  bit 6 \
  bit 7 /Plus CA2 and CB2 = 4 bits to drive the LED 7 segment

CC03 PIA1_ctrl b (CB2 select between player 1 and player 2 controls if cocktail)

CC04 PIA2_data a

  bit 0  Fire
  bit 1  Thrust
  bit 2  Smart Bomb
  bit 3  HyperSpace
  bit 4  2 Players
  bit 5  1 Player
  bit 6  Reverse
  bit 7  Down

CC05 PIA2_ctrl a

CC06 PIA2_data b

  bit 0  Up
  bit 1
  bit 2
  bit 3
  bit 4
  bit 5
  bit 6
  bit 7

CC07 PIA2_ctrl b

  Control the IRQ

D000 Select bank (C000-Cfff)
  0 = I/O
  1 = BANK 1
  2 = BANK 2
  3 = BANK 3
  7 = BANK 4