Exorcising (was RE: cine J14)

John Robertson wrote:
>
>>Could someone enlighten us as to what the Sig analyzer needs to work? I have
>>a Kurtz-Kash sig as well as teh "Cat Box (Atari)" analyzers, but I suspect
>>that one needs the "box" to convert the timing signals from the
>>Cinematronics
>>TTL processor into something that the standard sig anys can deal with. Is
>>this on the right track? Or is the process simpler than that?

To use the Cinematronics Exorcisor you will need the Exorcisor (Duh)
and a Signature Analyzer. That simple. Any model of analyzer should
do, I happened to use an HP5004B (A?) since that's what I like the
best. I'm not nuts about the 'feel' of the CAT box's probe and I don't
have a K-K though either would work just as well as an HP. Set-up
is very simple, two cables plug into the sockets where the DIP shunts
plug in, three 16-pin DIP clips attach to N2, R2 and T2 and a clip
lead attaches to TP8. The clock for the 'box' is grabbed off the board
at the CLOCK TP. The START/STOP/CLOCK pod hooks up to the Exorcisor.

The Exorcisor is not much more than a 28-bit wide pattern generator. It
takes the clock input and divides down the signal through a bunch of
counters then EXCLUSIVE-OR's various signals together to create unique
signals. These signals are used to drive various points on the CPU
in a STABLE and repeatable manner. All you have to do is probe the
various points in the circuit and match the signatures to those on the
schematics (if you can read them). Tracing bad signatures BACKWARD
through the circuits 'usually' leads to the defective device. I say
usually since there are always gotcha's ;-) It's nearly impossible to
narrow down the problem to one IC if there is feedback involved as in
the case of the board's Line Length Counter circuit :-( I was fighting
that battle yesterday and had to give up.

I'll upload the schematics, board layout and user manual (MS WORD) in
the form of a .zip file to WIRETAP this week.

Dave Fish | "We want...Information.
INFORMATION
Melrose, MA USA | You won't get it!
   dfish@bev.etn.com (work) | By hook or by crook we will"
> fishd@tiac.com (/work) | _The Prisoner_
>
Received on Wed Oct 15 08:58:13 1997