Subject: IO Files Pared to .ibs

From: "John Brennan (446-6982)" <[email-masked]>
Date: Mon, 1 Aug 94 15:42:11 EDT

Greetings,

I am generating a directory of IO circuit data where the
directory will contain the data for a given IO(what would be
under the [model] keyword). This data will be parsed
into a [component] by the chip designer. I want to mark
the IO by date, file rev, and ibis version. There are keywords for this
at the component level, but if I put these in my IO files,
there will be mulitple occurances of these keywords in a .ibs file
(1 occurance for each IO). Should I...

1.) leave the keywords in there since IBIS does not care if
    there are multiple occurances of these keywords.

2.) Comment them out, so the parsers will not see the dates, but
    they will still show up in the .ibs file as comments.

Also, is there any existing software out there that can read the
[Pin] keyword model_name, and given directory, go get the ibis data
for that file and append to the present file that would contain the
[Pin] list?

Please advise.

Thanks again,
John Brennan

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From: [email-masked] ( Bob Ross)
Date: Mon, 1 Aug 94 20:19:53 PDT

John and IBIS committee 

In response to your first question with respect to how IBIS currently works,
my recommendation is to do choice (2).  While some parsers may not
care about multiple occurances of certain keywords, other parsers based
on ibis_chk will reject some of the multiple occurances you want.  Also,
there is an explicit statement that [IBIS Ver] be the first keyword
encountered.  So there is an implicit assumption that all [Models]
within a file will be treated at the same [IBIS Ver] level.  Even though
you want to describe only [Model]s each file will need a [Component]
wrapper (even if it is a fictious component) with at least one pin
defined (which could be NC and not reference any models within) to 
pass ibis_chk.

I am not aware of any general, non-product-specific software that can
pick from [Pin] lists any referenced model from any directory.  However,
I am aware that equivalent capablility does exist within products through
various mechanisms and interfaces. 

Bob Ross
Interconnectix, Inc.