Mappy missing colors, blocky background on title screen

TheEnglishTear

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Hey all, working through this mappy Pcb that plays fine, however, the graphics are a bit messed up on the title screen and the mouse doesn't have the correct colors and was wondering if anyone can help me pinpoint the right chip. I have gq-4x and emp-20 programmer and have verified the graphics rom chips, but wasn't sure if I could use that to verify the 3 smaller proms on the video board or if it's an issue with the other chips. Thanks in advance for the advice!
 

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Check 5K

 
I can burn a 5k for you if you can't burn proms and drop it in the mail. MI to MI mail shouldn't take more than a day or two.
 
I can burn a 5k for you if you can't burn proms and drop it in the mail. MI to MI mail shouldn't take more than a day or two.
Thank you scuba. How might I be able to check the 5k? I have a emp20 and gq- 4x programmer but don't know if they are capable of reading and verifying. I also have a logic probe to test but now sure what to look for
 
I am not sure if those will work.
Check the device list against the part number in schematics. Then use the cross compatible list from mikes arcade to see what device (prom) you may be able to read that is the same.

Getting a compatible device on the list for reading has always worked for me. Sometimes burning does not.

Also some programmers will read proms but not burn the. In my experience.

Other option is to pop one out or another Mappy board and drop it in. If it works, that's your problem. I thought you said this was your third Mappy set.
 
I am not sure if those will work.
Check the device list against the part number in schematics. Then use the cross compatible list from mikes arcade to see what device (prom) you may be able to read that is the same.

Getting a compatible device on the list for reading has always worked for me. Sometimes burning does not.

Also some programmers will read proms but not burn the. In my experience.

Other option is to pop one out or another Mappy board and drop it in. If it works, that's your problem. I thought you said this was your third Mappy set.
Oh no, this is my first time working on a mappy. Just trying to help a friend get it going. I looked at the schematic and was confused on what the correct device part number was at 5k…do you happen to know the part number?
 
Oh no, this is my first time working on a mappy. Just trying to help a friend get it going. I looked at the schematic and was confused on what the correct device part number was at 5k…do you happen to know the part number?
It's in the thread I linked above.
8s129
Or 93427

 

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