Ghost & Fruit Sprites look funny (Color Ram 2a-2d) FIXED

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Ghost & Fruit Sprites look funny (Color Ram 2a-2d) FIXED

I pulled out this old project recently, intending to be productive while looking for new employment. Here's what I've done to it so far:

I pulled the board out for inspection and found corrosion on RAM 2C and 2D. (pic1)
Those got cleaned and reinstalled.

I put the board in a Ms Pac Man cabinet, powered it up, and the screen looked like a russian boot-leg. (pic2)

I pulled the board again, then slightly lifted 5E & 5F to reseat them. This revealed 3 broken pins.
I soldered new pins at E2, F2 (pic3), and F12. [no budget for new right now]

This worked great for a day-or-two in the Pac Man cabinet after fixing the monitor. (pic4)
https://forums.arcade-museum.com/showthread.php?t=405429&referrerid=70646


Today, I powered it up and the ghost sprites are buggered. (gif5)
Does anyone know what chip/pin would control just the ghost & cherry sprites?


*Also, the credit switch on the coin door needs to be held down for a second-or-two before it registers a credit and changes the coin counter. The red credit button next to the test switch works without issue, though.

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Last edited:
Looks like a missing eprom-data-pin.
Check pins and socket continuity of 5E and 5F.

There are 2 coin inputs on the edge connector (J & 8). Do they act the same?
 
I cleaned the edge connector and tweaked the coin switch wire. It is now registering every quarter!

I also reflowed the 5F socket pins and cleaned the 5-F 9332 Prom pins, but the ghosts and fruit are still interlaced (every other line is shifted up).

Looks like a missing eprom-data-pin.
Check pins and socket continuity of 5E and 5F.

There are 2 coin inputs on the edge connector (J & 8). Do they act the same?
 

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New dual-wipe sockets installed, but still getting weird sprites.

Upon closer inspection, it looks like Blinky & Inky bodies are fine.
Pinky, Clyde, Ghost Eyes, Blue Ghost, & Fruit are all missing every other line.

It seems as though either a part of 5F is corrupted, or maybe the ram is malfunctioning beyond that point.

What do you think? Does anyone know which ram handles the ghost sprites?
 
Well, crappy. I decided to swap ram around and hit a snag.
2A & 2B were both D2115AL-2 chips, so I swapped them and still had bad ghost sprites.
2c & 2d were both 93415 chips, so I started to pull 2c... and it crumbled to pieces (pic1).

Unfortunately, my Mrs Pac has soldered chips at 2a-d, so I can't pop in a new one to find out if that was causing my bad sprites.

I did notice that none of the 2a-d ram on the Pac had heatsinks, and only 3 on Mrs Pac had them. Do I need to find a place that sells both the ram & the heatsinks?

I swear, I spend more money on shipping these small orders than I do on the parts...
 

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What RAM options are there for Pac/MsPac 2a-2d?

I've seen:
93415
D2115AL-2
D2125

Are there others? At what point do you have issues with the RAM being too slow/fast?
 
In the end, it was 2c that handles the sprite colors. Replacing it resolved the issues.
 
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