Pacman board RAM error

R3LL1K

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So I bought a Pacman cab over the weekend and got around to tinkering with it. I vaccumed the inside after picking up all the rom chips from the bottom of the cab, tested out all of the voltages and hooked the monitor up.

Powered up the cab and I get a bootup screen and then two Ram error messages. The messages themselves look pretty bad. Does anyone have any suggestions on where to start or should I just Jammatize it and throw in a 60 in 1? :D
 
Depending on which one is bad sometimes you cannot read the screen. Its easy enough to swap a known good one starting on one end and work your way back. If you have old TI ram on there you probably have leg rot and all of them should be replaced.
 
And if that's not it, replace the 74LS245 chip on the same row as the 2114 SRAMs.
 
Replaced some of the ram and the board no longer gives the Bad RAM error. It's now rebooting. lol

I'll post a vid in a bit.
 
Yup... Reboots like that are generally a bad/dirty pin on a mask rom or a bad socket on row 6.
 
Yup... Reboots like that are generally a bad/dirty pin on a mask rom or a bad socket on row 6.
I'll try pulling the Roms tomorrow and cleaning the legs. If that doesn't work I assume the next step would be checking the sockets for continuity and replacing as necessary?
 
If your board still has any masked proms on it instead of eproms the first thing I do with those are throw them in the trash.
 
If your board still has any masked proms on it instead of eproms the first thing I do with those are throw them in the trash.
They're all eproms. The chips I found in the bottom of the cab were all masked proms with broken legs. I have a spare board which I'm sure they came off of. I'm sure the previous owner tried to get this cab going again at some point before I bought it.
 
Sorry for the late update. After getting rid of the ram issues I checked the eproms on row 6. One of them was inserted incorrectly and one of the legs got bent so it wasn't making contact with the socket. I have not attempted to repair the leg as I decided to run the 4n1 on this board. Ordered the eproms from Steph and will install them when I get a chance.
 
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