DigDug Hardware
0x0000-0x3FFF 16384 ROM, Write NOP (/* the only area different for each CPU */)
0x6800-0x681F 32 Device Write namco, namco_device, pacman_sound_w
0x6820-0x6827 8 Write bosco_latch_w (/* misc latches */)
0x6830 1 Device Write watchdog, watchdog_timer_device, reset_w
0x7000-0x70FF 256 Device Read/Write 06xx, namco_06xx_device, data_r, data_w
0x7100 1 Device Read/Write 06xx, namco_06xx_device, ctrl_r, ctrl_w
0x8000-0x83FF 1024 RAM Write, Shared digdug_videoram_w, videoram (/* tilemap RAM (bottom half of RAM 0 */)
0x8400-0x87FF 1024 RAM, Shared share1 (/* work RAM (top half for RAM 0 */)
0x8800-0x8BFF 1024 RAM, Shared digdug_objram (/* work RAM + sprite registers */)
0x9000-0x93FF 1024 RAM, Shared digdug_posram (/* work RAM + sprite registers */)
0x9800-0x9BFF 1024 RAM, Shared digdug_flpram (/* work RAM + sprite registers */)
0xA000-0xA007 8 Read NOP, Write digdug_PORT_w (/* video latches (spurious reads when setting latch bits) */)
0xB800-0xB83F 64 Device Read/Write earom, atari_vg_earom_device, read, write (/* non volatile memory data */)
0xB840 1 Device Write earom, atari_vg_earom_device, ctrl_w (/* non volatile memory control */)