galaga rom error?

powermeup

WARNING: Proceed with caution. Many members monies
Joined
Dec 25, 2007
Messages
730
Reaction score
0
Location
santa ana, California
game plays then screen scrambles, or plays upside down, or plays superfast. any guesses? test ram; ok rom; 04
 
Usual suspects are custom chips, sockets and resistor packs. No sense in doing any troubleshooting until those common problems are addressed.
 
More likely a bad socket than a ROM. I've seen 3 different kinds of sockets on those boards... one is a single wipe that contacts the inside of the chip legs... the second is a dual wipe socket that has gold contacts but spreads out over time. The third is a TI dual wipe socket that contacts on the skinny sides of the legs! What a crappy socket design!

It could also be a bad socket issue on a CPU.

RJ
 
Those sockets that wipe the edge of the legs are total crap. The only nice thing about them is the chips are easy to get out.
 
Check your voltages too. I had a similar board do this and all that was wrong is that the voltage was just a bit low on the voltage.
 
Back
Top Bottom