Al,
There is a company called Infinite Graphics Inc in
Minneapolis MN (612-721-6283) which has a product
called PAR. PAR which stands for Producibility Analysis
Report is a piece of software which runs on a sun platform.
Par reads in gerber data from a cad system (In our case it
is Allegro by Cadence) and does various checks against your
netlist. There are many manufacturing variables that may be set
to check for producibility, too many to mention so call them. Many
manufacturing houses are using PAR to check for manufacturing
problems on incoming data. PAR is useful because depending on
which type of fab house you send your boards to each house has
a different level to which they can fabricate to. Give them a call, or
if you want we have one person dedicated to PAR, his name is Jay
Murphy and he is always willing to help. Good Luck.

Mike Gnieski
Senior PCB Designer
EMC2 Corporation
Hopkinton, MA 
508-435-1000
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Original Text
>From [log in to unmask], on 10/20/95 11:40 AM:
Design Rule Checking

Kudos to the guy who first thought of, and implemented  "DRC".
It works very well right up to the time a designer produces gerber files.
But after that, we're on our own.

I understand that some Fab shops have the capability to run a DRC against 
the
customer supplied gerber files. Sometimes spacing errors are found. But how
could this be? Are cad operators not paying attention to their 
post-processing
reports? or are they changing apertures during the gerber process? or are 
Fab
shops changing aperture sizes and then running DRC's?

I would be happy to run a DRC against my gerber files, but I have yet to 
see
a cad system that can do it. We can simulate the artwork-select a .001 
grid-
and then view the simulation. But this is error prone and could make you go
blind.

Does software exist for a dos/unix system to run a DRC against the gerber 
files?
I don't care about neat graphics, just a program that will allow me to 
check
proper spacing of artwork features.

Al Slagle
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