I got a USA Raiden DX Jamma PCB w/ garbled backgrounds...

PC Engine Fan X! · Post by **PC Engine Fan X!** » Sat Mar 04, 2006 2:17 am

I just recently won an auction for a used (and very dusty) USA Bios region version Fabtek Raiden DX Jamma PCB. I cleaned up the Jamma edge connector with a pencil eraser and got it all really shiny with a Q-Tip dipped in some rubbing alcohol. I used a can of compressed air to try to clean up the top electronic parts side of the Raiden DX board but really would have to soak it to get it sparkling clean. There appears to be some rust on certain exterior parts upon further examination of this particular Raiden DX PCB. Upon booting it up, the sound effects and BGM music is 100% working. The title comes up with some strange numbers on the Raiden aircraft with some garbled graphical effects.

Upon starting a game, the enemy sprites & player sprites are 100% fine, it's the background scenery that is garbled. What can I do to fix the "garbled background scenery"?...if that could be fixed, then I would have a 100% working Raiden DX PCB.

PC Engine Fan X! ^_~

Post by **Dave_K.** » Sat Mar 04, 2006 2:52 am

I was going to bid on that same auction but I saw the description said "sold as is", and "worked last time I tested it, but don't have a cab anymore". Its total BS. I also saw you had put in the only bid and I didn't want to bid against you. Sorry it didn't turn out good. Sounds like you may have a bad rom/ram chip. I've herd people try flexing the board gently (press each chip) while its on to see if its a crack in the traces, or chip that is coming loose.

Post by **system11** » Sat Mar 04, 2006 11:17 am

The tile ROMs or associated chips/tracks are the problem (sometimes also known as character roms). Sadly I'm not familiar with the board type, so do basic checks first - check underneath for evidence of crossed legs, remove and refit any socketed chips. Next, gently push down on surface mount chips to see if a leg join has fractured, the backgrounds will change if so. Past that, you're into logic probe territory usually, try to work out which roms hold the character data and check all their IO and address lines.

antron · Post by **antron** » Sat Mar 04, 2006 4:45 pm

what type of roms do they use in PCBs these days?
i guess EPROM is no longer used.
if they are EEPROM you can write to them with an old motherboard (hotswap)