Atari Pit Fighter Graphics glitches

scottnagle

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Anyone know what would cause this type of glitch in the game play graphics? See pics...

It's an arcade upright cabinet.
 

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Looks like you have a bad line on the playfield ROM address bus (ROMs at 130M, 120M, 90M, 75M and 45M) and maybe a bad data line. Unfortunately, as with most 90s Atari games, the schematics don't include this part of the video hardware so you'll need to start at the ROMs and trace your way back.
 
Are these standard Rom chips, or are they specific to this game?

Where could I find them?

Or could I rotate the ones already in the board?
 
These are one-time-programmable ROMs specific to Pit Fighter, though they can be replaced with standard 27C512 EPROMs once programmed with the correct data. You can't rotate them with other ROMs on the PCB as their data is unique.

At the very least, I'd check to see if the contacts inside the ROM sockets are good and that the ROMs are properly seated. You could find somebody with a device programmer, have them read the ROMs and use MAME's -romident option to verify their integrity. At least one of the problems is likely related to something connected to the ROMs rather than the ROMs themselves however.
 
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