Path: utzoo!utgpu!water!watmath!clyde!gwu
From: gwu@clyde.ATT.COM (George Wu)
Newsgroups: sci.electronics
Subject: Re: Posting schematics...
Summary: We need a description with and without graphics.
Keywords: schematics EDIF
Message-ID: <23005@clyde.ATT.COM>
Date: 10 Mar 88 01:49:43 GMT
References: <1059@PT.CS.CMU.EDU> <999@spar.SPAR.SLB.COM>
Reply-To: gwu@clyde.UUCP (George Wu)
Organization: AT&T Bell Laboratories, Whippany NJ
Lines: 63

[ Standard disclaimer: I alone am responsible for this article's content. ]

In article <999@spar.SPAR.SLB.COM> malcolm@spar.slb.com (Malcolm Slaney) writes:
>In article <1059@PT.CS.CMU.EDU> phd@SPEECH1.CS.CMU.EDU (Paul Dietz) writes:
>>WE NEED A STANDARD FOR EXCHANGE OF SCHEMATICS!!!!!!!!!!!
>
>Check out the EDIF (Electronic Display Interchange Format??) standard.
>A number of vendors are supporting this standard for interchanging IC
>and PCB databases.  It is a Lisp-like langauge for specifying a heirarchical
>design.
>
>								Malcolm
>P.S.  The only vendor I am 100% positive is supporting EDIF is Cadnetix.
>I believe most of the rest of the industry is also supporting it but I
>don't have their names.


     Let's go over what we really want to be able to do with this description:

	o Describe the circuit in some graphical manner. We'd want this to be
	  as global as possible, so as many people as possible can see it. I'd
	  suggest Postscript, since it is widely used, and is essentially a
	  standard. What I believe is/will be *the* standard interface for
	  displays on-screen is X-Windows, and I'm sure there is/will be a
	  filter between X and Postscript format. Anyone know for sure?

	o An ASCII description of the circuit. That is to say, there should be
	  a public domain filter which would extract just this information,
	  for those of us who don't have access to an appropriate graphics
	  device. But what circuit descriptions are available? Spice? That
	  limits what type of devices we can have very much. EDIF? That's
	  supposed to be a standard. Does anyone know more about it; I don't.

	o A chip and wire level schematic? I'd guess that's what most people
	  here would want, since they may very well go off and build it
	  themselves. For a chip specification, CIF (Caltech Intermediate
	  Format) seemed to be the standard when I was into VLSIC CAD. Is
	  EDIF a chip level or a mask level description language? Or is it
	  general enough to do both?

     As of yet, I don't think any of the proposed formats fits these major
requirements. I think the really tricky part is how to take a graphical
description, such as Postscript, and extract circuit information from it.
Any ideas?

     And finally, could someone follow up Malcolm's EDIF suggestion with a
reference and where to get a copy of the paper? It's an IEEE standard, so
has a definitive article been published in a journal or magzine somewhere?
Note that it'd be better to use a magazine article, rather than a formal
paper, considering the logistics of distribution and such. (How would IEEE
respond if N-hundreds of us requested the same paper? Slowly, at best.)
Further note that this would have to be a good, detailed article, since many
people would have to know very specific details about EDIF to write filters
and such. A quick blurb wouldn't do at all.

     And really finally, kudos to Paul for this idea. I think the net has
just justified some of it's operating costs. Hear ye, management?

-- 
					George J Wu	

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