I got this Nintendo Vs board in a trade, someone had taken a heatgun to it at some point and done some damage to the board along with taking off a bunch of TTL, '104' capacitors and the eproms.
Once repopulated and fixing a blow out via caused by the heatgun damage I powered it on but the game did not run, just a solid green screen.
It's not shown in the picture but the top part of the board had a standard cpu installed, with Vs Super Mario Bros you need a dummy cpu in this socket for the game to be run.
Thankfully you can get away without having a dummy cpu and just bridge two pins on the cpu socket instead.
This got the game running but with some strange issues such as bad graphics, messed up scores, phantom coin inputs and other times it would run fine for 10-15 minutes.
I was worried it was going to be an issue with trace(s) caused by the heatgun damage and I was going to have to check every connection in the area with a multi meter. Before all that I went through and checked all the ram and TTL chips first as I already knew the cpu / ppu were fine from trying them on another board.
The trusty boardmaster 4000 flagged a 74LS157 @ 5J as having a stuck low output on pin 7.
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