Re: Testing Cinematronics CPU's

I think someone needs to take the time to build a "Monitor Saver" for
the XY games. My idea is something like the watchdog reset, but instead
of just resetting the game board, the monitor's power is CUT OFF untill
the board settles down. A simple relay driven by the RESET on the game
board or IRQ (if the IRQ is hit regularily, then relay times out if no
hits within a set time period) or whatever, a small capacitor on the
relay to give it a two second delay would be usefull too. This would
also help when the +5 disappears, as THAT is the power for the relay (as
I see it), the relay would be normally open (when no power) and only
when all conditions are right would the relay energize and then the
monitor would get it's power.

So who has some time to build this?

John :-#)#

Keith, Brendan wrote:
>
> I'm not suggesting pulling all the of the monitor inputs the other way.
> Just the MSB. That would result in the DAC putting out the middle value.
> That should result in the beam being centered. Only issue is the spot
> killer.
>
> It's not just for diagnostics. If you power up a previously working game
> but the board has died, the monitor won't have to go to the corner and
> blow out. My AA just did that last week.
>
> Brendan Keith
> brendan.keith@wilcom.com
>
> > ----------
> > From: jwelser@ccwf.cc.utexas.edu[SMTP:jwelser@ccwf.cc.utexas.edu]
> >
> > > I've been wondering about making a small change to the monitor.
> > > Namely, putting a pull-up (or is it pull-down) on the MSB of both DACs.
> > > Is my theory sound?
> >
> > Pulling the inputs the other way would most likely deflect the
> > beam to the opposite corner. I forget how the Cine Monitor gets its
> > datqa (but I think Zonn covers it in his writeup.)
> >
> > Why not just unplug the power to the monitor when you're
> > troubleshooting the board, rather than just unplugging the data cable?
> >
> >

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