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From: paul@dual.UUCP (Baker)
Newsgroups: net.arch
Subject: Re: More on Metastibility
Message-ID: <1146@dual.UUCP>
Date: Wed, 9-Oct-85 13:47:20 EDT
Article-I.D.: dual.1146
Posted: Wed Oct  9 13:47:20 1985
Date-Received: Sat, 12-Oct-85 14:59:17 EDT
References: <442@rna.UUCP>, <552@spar.UUCP> <211@fas.ri.cmu.edu.ARPA> <181@l5.uucp>
Organization: Dual Systems, Berkeley, CA
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> 
> All Sun VMEbus cards have good arbiters, with metastability calculated
> to be a problem once in a zillion years or so (based on the mfr's specs
> on the flipflops that capture and synchronize the signals coming in from
> the bus).

I would be very interested in seeing some manufacturer's specs on
metastability for, say, a 74S74.  There do seem to be rules of thumb
about such parts, but it is only in the last couple of years that I have
seen a manufacturer even admit that a problem might exist.  Fairchild
are the only company that has put out anything of any substance on the
matter, and only about their 74F series.

The academics, as usual, are silent about the problem as it is just
something messy to do with producing working equipment, and therefore
totally uninteresting.

Also, how many is a zillion?  I would suspect in this case about five to
ten.

Paul Wilcox-Baker.