Pacmania repair log #3

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Aug 132019
 

Got another Pacmania faulty.

This time the sprites were glitchy with some black lines

 

Custom 39 is usually involved in sprites generation but after testing with a good one problem remained.

There are two 74ls377 connected to it and one @A3 has one missing output.

Changing it fixed the board

 

 

Pac-Mania repair log #2

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Nov 092017
 

I bought a faulty Pac-Mania mainly for spare parts but I gave him a chance and tried to repair it

The game was missing sound roms, after replacing them, game booted and you could play but the screen was totally a mess.

After some blind testing I started test all socketed custom chips and rams against new ones and I eventually found the culprit

in the “text” ram @L5!

It was so bad that it totally covered the screen with junk graphics

Replacing it fixed the game 100%