RE: Signature Analysis/CAT Box question

I suspect you need to insert a NOP modified CPU to get the signatures, I
believe that the CAT box does the NOP in this case, but I don't remember
noticing that in the docs on my CAT, probably you are just doing a write to
an area of memory...

Signature is normally the reading of a signal that is clocked between a
Start and Stop point on either a rising or falling edge, the bits are
counted and the display give a reading of some magic done on the count. The
letters in the Sig are arbitrary letters that could show the count from 10
to 15 on a 7 segment LED display. That is about it for my understanding of
the process, and I probably have it wrong... sigh... but it works!

John :-#)#

At 01:34 AM 10/10/1999 -0400, you wrote:
>John,
>
> As far as reading the signatures, you are correct. The CAT Box and an
>HP read them the same. What I am looking for though, is what is the CAT Box
>doing to the board to create those signatures. Because the instructions say
>to remove the CPU, then the CAT Box has to be controlling the board during
>the analysis. What it does to control it though, is not clearly documented.
>If I can find that out, I can probably do the sig analysis w/o a CAT Box.
>
>Thanks,
>-Chris
>
>-----Original Message-----

From: John Robertson
>To: vectorlist@lists.cc.utexas.edu
>Sent: 10/10/99 12:34 AM
>Subject: Re: Signature Analysis/CAT Box question
>
>There is no difference between the Cat Box signature analysis and an HP
>or
>Fluke signature analyzer. They were trying to sell Cat Boxes after
>all...
>I am sending Al the info that I have accumulated on Sig. Analysis,
>including some manuals from HP that cover the theory and application of
>the
>process. I imagine he will put it up on spies when he gets a chance. I
>suspect he has a life besides scanning...seems to travel a bit...(Hi
>Al!)
>
>John :-#)#
>
>At 12:19 AM 10/10/1999 -0400, you wrote:
>
> >I have been trying to repair a Space Duel board recently that has me a
> >little stumpped at the moment. Using a Fluke 9100, all RAM/ROM test
>OK, but
> >it still won't go into the test screen. This leads me to the
>conclusion
> >that is is a vector generator problem. While looking for other ways to
> >troubleshoot this, I began looking through the CAT Box test procedures
>in
> >the schematics and came to the Signature Analysis section which tests a
> >number of the control lines like VGGO. I've done sig analysis on
>Battlezone
> >boards where it is all built into the board, but Space Duel wants the
>CAT
> >Box to do the analysis. It just says to put the CAT Box in signature
> >analysis mode. Trying to figure out what that did, I looked in the CAT
>Box
> >manual from Spies and it just says that it increments the address
>lines.
> >Does anyone know more specifically what the CAT Box does in signature
> >analysis mode? If it is just repeatedly incrementing the address
>lines,
> >does anyone know what the beginning and ending addresses are?
>Hopefully, I
> >can simuluate whatever the CAT Box is doing on the Fluke.
> >
> >Thanks,
> >-Chris
>
>
> John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
> Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
> http://www.flippers.com
> "Old pinballers never die, they just flip out."

  John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
  Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
  http://www.flippers.com
         "Old pinballers never die, they just flip out."
Received on Sun Oct 10 00:46:52 1999