From: Marko Mäkelä (marko.makela_at_hut.fi)
Date: 2004-11-19 14:27:35
On Wed, Nov 17, 2004 at 08:40:10PM -0500, William Levak wrote:
> Did you measure the voltage on the CASS SENSE line? A logic probe would
> be ideal. It is normally at +5V, and is pulled low when the play switch
> is depressed.
It was about 1.1 volts. After I disconnected pin 26 of the processor
from the CASS SENSE line, it was much higher (I don't remember how much,
but I think it was well over 3 volts.)
> If your 8502 is socketed you can test it by pulling it up and bending out
> pin 26. If the problem persists, the 8502 is definitely bad.
The disconnected pin 26 was at -.462 volts. I first misread it as -4.62
and wondered if I had flipped the polarity. So, it looks like the 8502
is broken. :-(
Marko
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