Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site spar.UUCP Path: utzoo!linus!decvax!decwrl!spar!baba From: baba@spar.UUCP (Baba ROM DOS) Newsgroups: net.micro.68k,net.arch Subject: Re: Multiple 68020's on VME ? Message-ID: <552@spar.UUCP> Date: Mon, 30-Sep-85 14:56:08 EDT Article-I.D.: spar.552 Posted: Mon Sep 30 14:56:08 1985 Date-Received: Wed, 2-Oct-85 20:45:12 EDT References: <442@rna.UUCP> Organization: The Institute for Impure Science Lines: 18 Xref: linus net.micro.68k:1107 net.arch:1622 > > We would like to hear from people who know about or who have > used multiple 680XX's on a bus. We are tentatively considering a ~10 > processor machine using 68020's on VME for a particular real-time > data collection, analysis and display application. > > > Cheers, > Dan Ts'o The August 1, 1985 issue of Computer Design contains a rather interesting article on metastability problems in multiprocessor VME systems. It appears to be a little trickier than expected to design VME bus and memory arbitration logic that is not vulnerable to metastability problems in synchronization. In particular, some folks at CMU's robotics lab discovered that "as few as two" 8-MHz Motorola VM02 68000 boards would lock up "within 4 to 10 minutes". Baba ROM DOS Brought to you by Super Global Mega Corp .com