Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site gvax.cs.cornell.edu
Path: utzoo!watmath!clyde!burl!ulysses!bellcore!decvax!tektronix!uw-beaver!bullwinkle!gvax!jqj
From: jqj@gvax.cs.cornell.edu (J Q Johnson)
Newsgroups: net.arch
Subject: Re: Addressing modes
Message-ID: <177@gvax.cs.cornell.edu>
Date: Tue, 18-Feb-86 06:13:41 EST
Article-I.D.: gvax.177
Posted: Tue Feb 18 06:13:41 1986
Date-Received: Fri, 21-Feb-86 04:46:11 EST
References: <946@garfield.UUCP> <3421@nsc.UUCP> <1404@gitpyr.UUCP> <175@oasys.UUCP>
Reply-To: jqj@cornell.UUCP (J Q Johnson)
Organization: Cornell Univ. Cs Dept, Ithaca NY
Lines: 17

In article <175@oasys.UUCP> maa@oasys.UUCP writes:
>There was a computer in the basement of the University of Colorado EE building 
>that I spent quite a lot of time playing with.  It's name was GPL-3055, built
>by the Librascope division of General Precision.  [There were only three of
>these ever built--for the DoD of course :-)]
>
>This computer supported infinate inderection with indexing at every level.  
>I think it's a shame that all these wondedful old computers with strange
>architectures are being retired.

The PDP-10 architecture (DEC-10, DEC-20, etc.), of which there were 
substantially more than 3 built, also has infinite indirection with indexing
at every level.  In fact, one frequently uses multiple levels of indirection,
though generally only one or two indexing operations.

Yes, it's a shame the PDP-10 is being retired.  It was a nice machine, and
the mainstay of computer science research (especially AI) for a decade.