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SmokeMonster

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I have a Namco Classics Vol 2 PCB that won't save changes to the service menu. I've tried resetting it to default, and even those changes aren't saved after a reboot. High scores are also not saved.

This PCB uses an AT28C16 to save high scores. Is this the same chip that stores the service menu options? If so, would socketing/replacing the AT28C16 solve the problems? It's like the chip is read-only right now.
 
Is the black component marked ●330 a battery or something?

20160628_162632.jpg
 
The AT28C16 holds the high scores and test menu settings.
Changing the AT28C16 may help. Possibly not.
First, check CE/OE/WE (get the datasheet)
Go to the test mode and change some settings then exit. Do that while probing the pins with a logic probe.
You should see things change from read mode to write mode as you exit the test mode.
In write mode they should be...
CE = Low
OE = High
WE = Low
If the pins are correct the chip is bad and just change it.
If those pins are not correct the chip can't be written to and you have a more serious fault. You would need to trace those pins to wherever they go and that's where the problem will be. You may have a bad/broken trace somewhere. You may have a bad chip somewhere. However most PCBs that are surface-mounted and as complex as Namco Classics is are unlikely to be fixed by the average Joe game player.

Alternatively pull out the chip and add a socket. Then run the game in MAME, change the settings to how you want them then take the AT28C16 EEPROM file that MAME creates and re-program the data using an EPROM programmer. Plug the chip in and your test mode settings problem may be solved. It still won't save high scores of course. For that you'll need to actually fix the PCB.....
 
Thanks for the help Mr T. I didn't see that you had responded or I would have thanked you sooner!

Socketing and replacing the AT28C16 fixed the problem. The board detected the blank EEPROM and set it up at first boot. Pretty cool.
 
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