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Memory Map

The following is a memory map that was generated based on the MAME source code (.180).  This information is only as accurate as the MAME driver is.  If you see any errors, please let me know what that error is.
 
The Memory Area is related to where the information is from (CPU, Sound Board, etc..), and it may also reflect what it has in common with other hardware.
Off the Wall (Atari Games, 1991)
Memory Area:main_map
Address RangeLengthFunctionDescription
0x0000-0x37FFF229376ROM
0x38000-0x3FFFF32768Read, Region, Sharedbankrom_r, maincpu, 0x38000, bankrom_base
0x120000-0x120FFF4096Device Read/Write 8-biteeprom, atari_eeprom_device, read, write, 0x00ff
0x260000-0x2600012Read Port260000
0x0001Button 4Active Low
0x0002Button 1Active Low
0x0004Button 2Active Low
0x0008Button 3Active Low
0x0010Joystick RightActive Low
0x0020Joystick LeftActive Low
0x0040Joystick DownActive Low
0x0080Joystick UpActive Low
0x0100Button 4Active Low
0x0200Button 1Active Low
0x0400Button 2Active Low
0x0800Button 3Active Low
0x1000Joystick RightActive Low
0x2000Joystick LeftActive Low
0x4000Joystick DownActive Low
0x8000Joystick UpActive Low
0x260002-0x2600032Read Port260002
0x00ffUnusedActive Low
0x0100Button 4Active Low
0x0200Button 1Active Low
0x0400Button 2Active Low
0x0800Button 3Active Low
0x1000Joystick RightActive Low
0x2000Joystick LeftActive Low
0x4000Joystick DownActive Low
0x8000Joystick UpActive Low
0x260010-0x2600112Read Port260010
0x0001UnusedActive Low
0x0000Whirly-gigsActive High
0x0002JoysticksActive High
0x0004UnusedActive Low
0x0008UnusedActive Low
0x0010UnusedActive Low
0x0020CustomActive Low
0x0080CustomActive Low
0xff00UnusedActive Low
0x260012-0x2600132Read Port260012
0xffffUnusedActive Low
0x260020-0x2600212Read Port260020
0x00ffDial VActive High
0xff00UnusedActive Low
0x260022-0x2600232Read Port260022
0x00ffDialActive High
0xff00UnusedActive Low
0x260024-0x2600252Read Port260024
0x00ffDial VActive High
0xff00UnusedActive Low
0x260030-0x2600312Device Read 8-bitjsa, atari_jsa_iii_device, main_response_r, 0x00ff
0x260040-0x2600412Device Write 8-bitjsa, atari_jsa_iii_device, main_command_w, 0x00ff
0x260050-0x2600512Writeio_latch_w
0x260060-0x2600612Device Writeeeprom, atari_eeprom_device, unlock_write
0x2A0000-0x2A00012Device Writewatchdog, watchdog_timer_device, reset16_w
0x3E0000-0x3E0FFF4096RAM Device Write, Sharedpalette, palette_device, write, palette
0x3EFFC0-0x3EFFFF64Device Read/Writevad, atari_vad_device, control_read, control_write
0x3F4000-0x3F5EFF7936RAM Device Write, Sharedvad, atari_vad_device, playfield_latched_msb_w, vad:playfield
0x3F5F00-0x3F5F7F128RAM, Sharedvad:eof
0x3F5F80-0x3F5FFF128RAM, Sharedvad:mob:slip
0x3F6000-0x3F7FFF8192RAM Device Write, Sharedvad, atari_vad_device, playfield_upper_w, vad:playfield_ext
0x3F8000-0x3FCFFF20480RAM
0x3FD000-0x3FD7FF2048RAM, Sharedvad:mob
0x3FD800-0x3FFFFF10240RAM, Sharedmainram
 

ROM Map for this game

 
This is the ROM map for the game.  This should tell you what address the ROM is at, how big it is, what it's used for.   
Memory Area:eeprom:eeprom
Address RangeLengthLabel/LocationDescription
0x0000-0x07FF2048offtwall-eeprom.17lCRC(5eaf2d5b)
0x0000-0x07FF2048offtwall-eeprom.17lCRC(5eaf2d5b)
Memory Area:gfx1
Address RangeLengthLabel/LocationDescription
0x0000-0x1FFFF131072136090-1014.14sCRC(4d64507e) (Fluke: D2A5)
0x20000-0x3FFFF131072136090-1016.14pCRC(f5454f3a) (Fluke: D377)
0x40000-0x5FFFF131072136090-1018.14mCRC(17864231) (Fluke: 9BD5)
0x60000-0x7FFFF131072136090-1015.18sCRC(271f7856) (Fluke: 8718)
0x80000-0x9FFFF131072136090-1017.18pCRC(7f7f8012) (Fluke: 3987)
0xA0000-0xBFFFF131072136090-1019.18mCRC(9efe511b) (Fluke: 8B7F)
Memory Area:jsa:cpu
Address RangeLengthLabel/LocationDescription
0x0000-0xFFFF65536136090-1020.12cCRC(488112a5) (Fluke: BE97)
0x0000-0xFFFF65536136090-1020.12cCRC(488112a5) (Fluke: BE97)
Memory Area:jsa:plds
Address RangeLengthLabel/LocationDescription
0x0000-0x0116279136085-1038.17c.binGAL16V8A-25LP is read protected
0x0118-0x022E279136085-1039.20c.binGAL16V8A-25LP is read protected
Memory Area:main:plds
Address RangeLengthLabel/LocationDescription
0x0000-0x201C8221136090-1001.14l.binGAL6001-35P is read protected
0x201E-0x2134279136090-1002.11r.binGAL16V8A-25LP is read protected
0x2135-0x224B279136090-1003.15f.binCRC(5e723b46),GAL16V8A-25LP
0x224C-0x2362279136090-1005.5n.binGAL16V8A-25LP is read protected
0x2363-0x2479279136090-1006.5f.binGAL16V8A-25LP is read protected
0x247A-0x2590279136090-1007.3f.binGAL16V8A-25LP is read protected
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