TMNT pcb doesnt boot

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TMNT pcb has graphical glitches

i have a Broken Tmnt pcb that at the rom check its all glitchy and from then it plays, but it has bars of colors arcross the screen every inch or so, idk what to do. picture provided
 

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Alright, i got it to boot, and it plays, but there is thick bars covering every inch or so of the screen.
 
Have you tried pulling and reseating the ROMs? It helps to do it one at a time so you don't get them mixed up.

ken
 
maybe i should have added that i just cleaned it up from a crap load of oxidation and rust, replaced some caps and got it to actually run, just not well.
 
Looks like a logic fault to me, very common if the board is peppered with F branded TTL chips. No simple fix I'm afraid, other than to track down the bad ones and replace, they won't be socketed.
 
You need a logic probe and a multimeter at a min.

The blocks looks like something wrong with the timing to the ram chips and I would look at the crystals. The traces could be bad to a chip or clock chip. Check all traces from crystals and ram chips, visually looking for broken/cut traces.

I have not looked at a schematic for this game but I have seen where a bad clock chip will cause this issue.
 
Go into test mode and run the ROM test. The power-on self tests don't test all the graphics ROMs.
 
ive gotten it into test mode, but when i go to check roms it just halts at screen check mask roms........?? :(
 
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well the rom check randomly showed up saying k27 i think was bad, i had a hard time making out the letters / numbers
 
Here is a little help from my good board.

When you do the mask ROM check in the test menu the screen goes crazy for the first 20 seconds, the game then tests all the ROMs in order and the total test takes almost 3 minutes.

When it is finished you should see something like my picture. You should be able to use my picture to identify which ROMs are reporting bad.

Brian.
 

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for the mask roms test, it says mask rom test for like 20 secs, then it goes into a crazy lightshow for about a min, then it shows me which ones are good / bad
 
Hang on, guys.
I'm an idiot. I posted a picture of the Simpsons mask ROM check.

Noobs, I'm at dinner right now but I will get you the correct info from my TMNT in an hour when I get home.

Sorry about that. :(

Brian
 
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