RE: Testing Cinematronics CPU's

On Thu, 31 Dec 1998, Keith, Brendan wrote:

> 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.
>

        When the board dies, the board will conceivably pull the inputs to
the monitor in some "random" way, since I don't think they get tri-stated.

        Since your pull-up/pull-down would have to be weak enough to not
affect the normal operation of the monitor, it wouldn't affect the
"failure-mode" operation, either, where the game board is pulling the,
inputs, just not in the way you'd like it to....(i.e. all high or all
low might be common cases...)

Joe
Received on Thu Dec 31 11:57:07 1998