VECTORLIST - The Mailing List For The Technical Discussion of Vector-Based Arcade Games

February_1999
RE: Star Wars/Wells Gardner 6100 Problem


From: Clay Cowgill ( )
Date: Tue Feb 02 1999 - 19:46:03 CST


> A couple games later, he switched it back to ESB, and it still did not
> display video, so he switched back to Star Wars, and now that was not
> displaying video either.
>
For what it's worth, this is what killed my monitor when I was *first*
working on the kits-- hence the warning about switching with the game
on.

Clay's techy idea on what can happen:

I think you can switch and still have the code land in a segment that
refreshes the watchdog, but the vector generator crashes.
Max-deflection for very long = dead monitor. Someday I should probably
redesign the kit to have the bank-selection switch go into a PAL and
then have the PAL yank reset for a few clocks after the switch changes
states. I'd want to *really* fix those nasty old 2212 NOVRAMs at the
same time though by replacing it with some kind of EEPROM, so the
project gets larger and I keep putting it off...

-Clay


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