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From: cottrell@NBS-VMS
Newsgroups: net.unix-wizards
Subject: Clear Core
Message-ID: <9149@brl-tgr.ARPA>
Date: Tue, 12-Mar-85 11:37:24 EST
Article-I.D.: brl-tgr.9149
Posted: Tue Mar 12 11:37:24 1985
Date-Received: Fri, 15-Mar-85 01:45:30 EST
Sender: news@brl-tgr.ARPA
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/*
> Close, but no cigar - at least on my 11's.  The push on the stack at
> 177776 gives a bus timeout trap, the attempted push to service the trap
> does different (processor-type dependent) things.  Like make an emergency
> stack at 4 and push 2 words on it (11/40, 11/23).  I didn't try it on an
> 11/2, but I know that it would fatally hang an 11/20 with a double bus error.

What you say is true. The pdp-11 has an I/O space in the last 8k bytes
that is not going to act like memory. The first 400(8) bytes are also
special to the processor but will probably act like real memory. 
However, permit me to make a few assumptions about the environment I am
executing in. Both this `program' and the one-instruxion clear core
`move -(pc),-(pc)' are executing in user virtual space with all segments
mapped to real core. Neat machine either way.

	jim		cottrell@nbs
*/