Random garbage (no sprites) and occasional random sounds, reboots randomly. Clock looks good, CPU and bus address and data lines have what appears to be otherwise normal activity (i.e. nothing appears stuck or floating). Pulled EPROMs and Romidented them; Romident does not identify all but 2 of them, and the two that are identified are not identified as Kicker ROMs!
OK, so I pull the EPROM archive for Kicker, and match them up that way. Three of them match up, four do not. Hmmm… One of the EPROMs does not erase(!). Going digging for a replacement…
Solution: None yet.
Purchased described as “dead”. Started by creating a JAMMA adapter (I hate creating adapters, it is tedious work). Well, the description was correct – she is dead alright: screen has static garbage and required some tweaking to sync correctly on my test bench monitor.
Watchdog is barking, disabling it has no effect on the screen’s contents. Board already had some previous work done in it, solder-side contains more than 20 jumps to connect some RAMs back onto the bus. The Parts side shows the missing/removed/blown traces being jumped.
Started by checking the daughterboard, seems OK. Next I remove, socket and replace the 74LS245s on the board because word has it that they tend to be the cause of most problems, the Galaxian Trouble Shooting Logic Board manuals lists similar symptoms connected to those chips, and the Fluke 9010 troubleshooter says that the address lines are tied. Other than that, I cannot come up with a good way to check them! 🙂
Gotta wait for some replacement sockets and chips to come in…
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