Carnival hardware - wiring to JAMMA ?

Archived from groups: rec.games.video.arcade.collecting (More info?)

I'm trying to fix a Sega Space Trek boardset (basically Carnival
hardware) - am though getting a problem with the Reset circuit and can
only get the boardset to run if I disconnect the Z80's Reset pin and
pull it high.

I can't see anything obviously wrong with the reset circuit itself so
am wondering if I need to do anything to 'fudge' the reset when using
it on my JAMMA test rig.

I see that there is an AC input to pin 3 on the 'A' connector on the
large PCB - this drives the transistors that drive the 555 then a
couple of other chips up to the Reset pin on the Z80. I assume that
since I can get the board running by forcing Reset high then it
*should* work in the original cab as that would be providing the
relevant AC voltage to the aforementioned pin on the molex connector?

So if I simply pull-up pin 26, do my testing and return the boards for
insertion into the original cab then all should be well ...... I hope.

Or am I going about this the wrong way? I've never tested one of these
before.

Any thoughts please folks?


Thanks