RE: Cinematronics CPU board problem

On schematic page 4 of 7 at B8/7 - there are signatures related to
"Address Mode". Have you verified those and is address mode set correctly?

You can use two 2532 eproms instead of four 2716 eproms without having to
modify your board as outlined here.
http://www.ionpool.net/arcade/cine/tailgunner-2532-replacement.txt [1]

I've seen one case where the board would work with the two 2532 eproms but
not the four 2716's. I never bothered to figure out why. :)

Are there any sections of the board that aren't tested with signature
analysis other than parts of the clock and reset circuitry?

Matt

On Mon, 19 Jan 2009 16:43:18 -0500, "David Fish" wrote:

Could be bad scratchpad RAM. Try replacing the 2102A's @L-14, M-14 and
N-14.

Dave

FROM: owner-vectorlist@vectorlist.org
[mailto:owner-vectorlist@vectorlist.org] ON BEHALF OF Matt Rossiter
SENT: Monday, January 19, 2009 11:52 AM
TO: Vectorlist
SUBJECT: Re: VECTOR: Cinematronics CPU board problem
IMPORTANCE: Low

Man, I feel
your pain there. I have a couple of boards like that too.

Sometimes you need to reverse the clock position to get alternate
signatures as listed in the manual.
Double-check the power-up circuit on Page 5 of 7
Make sure the JMI jumper is set correctly, which I'm sure it is.

You might have to scrap the signature analysis and start from the RESET
line with an oscilloscope and work back that way.

Other than that - hopefully some of the experts on this list can advise
you because I could use a little help as well. :)

Matt

On Sun, 18 Jan 2009 22:37:38 -0500, "William Boucher" wrote:

Has anyone ever been doing Cine CPU troubleshooting using an exorciser
setup and found 100% of the signatures to be correct but the board still
won't run? I'm having this problem with a Rip Off CCPU. It is not a mod'ed
board (meaning it uses 2716 eprom's). I've tested or replaced about 30
chips including the eproms, a few bipolar d_roms, some 74LS163 counters
that were messed up, a few gates, all
the 74LS377's, the 74LS181's, the ram
chips, all of the original chip sockets, and so on. Like I said, all the
sigs are perfect. I tried the "load loop timer" test, the "spac" test, the
"no-op" test, and the standard test. I've done them all 3x or more. The old
original docs are loaded with numerical errors but I have sorted them all
out already. The PCB is very clean, no open traces that I can find, no
missing pads, no broken resistors or caps, etc. It is visually perfect. All
the clock signals are perfect as well.

I had a stack of about 10 old CCPU's and I finally decided to repair them
all. I whipped through the batch and fixed 6 of them within a couple of
days. I'm now down to just 3 left. I probably should move on to the last 2
boards and come back to this one last, but I don't want to let it beat me.
I'll keep at it even if I have to replace every last chip on the whole
board one at a time if that's what it takes. At this point, I'm simply out
of ideas.

One of my other
boards that doesn't work also has all good signatures as
well. I can only hope that it doesn't turn out to be the same nightmare all
over again. I don't really understand how all of the signatures can be
correct and the roms all verified and the ram replaced with known-good
chips and the thing still won't run.

Any thoughts or suggestions?

William Boucher

http://www.biltronix.com/arcade_01.html [2]

Links:
------
[1] http://www.ionpool.net/arcade/cine/tailgunner-2532-replacement.txt
[2] http://www.biltronix.com/arcade_01.html

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Received on Tue Jan 20 14:09:05 2009