Re: Star Wars/Wells Gardner 6100 Problem

What if the game change switch had a small circuit added that forced a
reset that lasted X amount of time? A 555 timer could be kludged in
pretty easily...or it could just pull the MPU reset down...

John :-#)#

Clay Cowgill wrote:
>
> > 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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