Data East Captain America

CharlieFriday

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Hey all, I have a Captain America that had vertical lines through the sprites.

I reflowed the rom sockets and finally found a lifted pin leg on the surface mount chip 52.

I repaired that and continuity seems to be solid for the two legs I needed to resolder.

Any tips as to where to look next? I've attached a pic of the chip repair for inspection.
 

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If you are sure all legs on chip 52 are making good contact and there are no broken traces then the most likely thing is a failed mask ROM.

A logic probe on the ROM data pins might confirm a stuck bit (it might not as the line might be multiplexed, would have to check).
 
I think?

The game was booting before I started the repair so I don't know how I could have messed those up. I'm going to Double check everything later today.
 
Hi, no, I'm not suggesting you broke the mask ROMs in any way - they can fail by themselves over time. The usual failure is a data bit will stick high (or sometimes low) and because of the layout of the sprite data, this is usually seen on screen as a vertical line down all the sprites.

If you can confirm and identify the failed mask ROM you can burn an EPROM as replacement to fix the game.

Data East mask ROMS are usually quite reliable - but Fighters History and Captain America are two games that seem to show this problem more than others.
 
Ok to update this...

It can fix if I press on the pcb, and I've gotten it to look correct/perfect for a bit, but if I breathe on the pcb or touch it in any way it'll recur.

Pressing also can make the lines more or less present.

Thoughts? Cracked trace? Is that a thing?
 
Almost certainly you need to reflow chip 52.

That did the trick!

I now have a new issue. I either have sound or I don't.

Dirty sound pot? It was ok for a good 5 minutes then just stopped.

Thank you guys so much for helping me fix this issue!
 
Went back again over it with fresh eyes and found a few pins still loose on 52. Tacked they down, cleaned the sound pot and it's rock solid now!
 
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