Re: Pokey failure??

They seem to generally be used for the random number generator,
sounds (audio) and sometimes they connect a DIP to them and use
them for game configuration input. The chip itself has a bunch
of logic for reading game paddle inputs (POts) and scanning
keyboard matrixes (KEY), hence the POKEY. It also contains logic
for serial input and output. I guess they used this chip in
their home game console games or something.

There is not much the CPU can do to perform any automatic test
on them except the random number generator test, this is because
the registers on the chip have different functions for read
versus write, so they are unable to run a typical register
test against them (one that writes values and then reads them
back to see if they match). I think it was millipede that I
saw that did the random number selftest and displayed a "P0"
or "P1" to indicate the failed pokey.

Joe Magiera wrote:
>
> Funny (not really) this should be brought up. Just this week, I was
> putting Major Havoc (Gravitar conversion) through self tests to check it
> out. The self test gave a "J" error, which indicates an error at 13Q (I
> think it's "Q"). Sure enough, thats the Quad Pokey Eliminator board.
> It doesn't identify which one is bad, so I started self testing them on
> the Black Widow right next to it. I went through 26 pokey chips, and
> only 1 passed the self test in Black Widow. I was really wondering what
> was wrong because the sound test appeared to be fine (that was my
> question previously if there was a sound on Major Havoc on sound #17).
> I changed the pokeys so much on the Black Widow, I screwed up the trace
> underneath the pokey and the board went out.
>
> I tested a few in a raster game at a friends, I don't remember if it was
> Crystal Castles or Centipede, but they don't indicate a screen error if
> it doesn't like the pokey there. The manual just basically says go
> through all the sounds and if there is one that is bad, fix the pokey.
>
> I was wondering, is it only the vector games that do some kind of extra
> testing on a pokey? And if so, what is this test it is running? I know
> pokey's are for sound and other I/O. Maybe the raster games just used
> them for sound and the vectors use them for I/O and it was failing
> there?
>
> Joe
> joemagiera@ameritech.net
>
> MKDUD@aol.com wrote:
> >
> > Hello,
> >
> > I was just wondering how often people have had pokeys fail. Over the
> > past week, I had to replace one in Tempest, Space Duel, and Centipede. I was
> > curious as to whether anybody else had anything similar happen.
> >
> > Thanks,
> > Michael Kelley
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Received on Thu Jan 10 20:34:07 2002