Archive for June, 2003

Dig-Dug (“Has a ROM Error”)

Saturday, June 28th, 2003

Purchased described as “Has a ROM error“. Started by creating a JAMMA adapter, and then read the EPROM at 2E, it was not found under Romident, burned and installed a replacement. No change. Removed and read all ROMs in row/column 2, and all but one of them failed to be identified by Romident, burned and installed 5 more replacements, working! Still have to wire up an amplifier to correctly test the sound, but looks good so far.

[07/30/03] I finally found the brain cell that got me to realize that I could use my inductive listener (a telecom tool, often used with a tone tracer) to test the sound. It works!

Solution: Replaced bad ROMs

(Recently, the board is starting to develop an intermittent problem with a bad socket. I am going to replace it as the first use of my soon-to-be-here combination soldering/desoldering station.)

Gyruss (Konami, bootleg)

Friday, June 27th, 2003

Boots and passes self-test, but immediately coins itself up and starts playing itself(!), although not too well.

Well, it looks like some of the inputs are firing rapidly and randomly. Grounding one of the enable pins on one of the 74LS253s seems to make it settle down for a few seconds, so I will try playing with it.

[07/30/03] Update #1: OK, it looks like one of the outputs (za) is always low on the 74LS253, regardless of its inputs. Will try swapping it out.

Solution: None yet.