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From: binder@dosadi.DEC (The Stainless Steel Rat)
Newsgroups: net.micro.apple
Subject: Weird opcodes
Message-ID: <2202@decwrl.UUCP>
Date: Mon, 2-Jul-84 09:01:21 EDT
Article-I.D.: decwrl.2202
Posted: Mon Jul  2 09:01:21 1984
Date-Received: Tue, 3-Jul-84 04:40:51 EDT
Sender: daemon@decwrl.UUCP
Organization: DEC Engineering Network
Lines: 19

This discussion doesn't seem to relate to Apples, but this is where it
started, so... 

I can't fathom the Halt-and-branch instruction, maybe it should read
Branch-and-halt? 

The MODCOMP II's instruction set includes a series of 26xx (hex)
opcodes.  26FF is unimplemented but not trapped out.  It stores 26FF
into the location following the current PC and then executes it. 
Discovered accidentally, ended up being used by at least one US Air
Force installation to clear >>core<< memory. 

Cheers,
Dick Binder   (The Stainless Steel Rat)

UUCP:  { decvax, allegra, ucbvax }!decwrl!dec-rhea!dec-dosadi!binder
ARPA:  binder%dosadi.DEC@decwrl.ARPA

Posted Monday 2nd July 1984, 09:02 EDT by DOSADI::BINDER