Path: utzoo!mnetor!uunet!husc6!uwvax!rutgers!rochester!PT.CS.CMU.EDU!cadre!pitt!hoffman
From: hoffman@pitt.UUCP (Bob Hoffman)
Newsgroups: comp.sys.dec
Subject: Re: pdp questions...
Message-ID: <2229@pitt.UUCP>
Date: 22 Dec 87 17:33:22 GMT
References: <16886@gatech.edu> <3538@aw.sei.cmu.edu>
Reply-To: hoffman@pitt.UUCP (Bob Hoffman)
Organization: Univ. of Pittsburgh Computer Science
Lines: 27

In article <3538@aw.sei.cmu.edu> pdb@sei.cmu.edu (Pat Barron) writes:
>  The 11/23, 11/23+ and 11/24 use the exact same CPU (the F-11 chipset).  The
>11/23 and 11/23+ are Q-bus, while the 11/24 is Unibus.  The 11/23+ has space
>for bootstrap ROMs, and also has serial ports (two, I believe) that the 11/23
>does not have.

The 11/24 also had enough 40 pin sockets to accept both the Floating Point and
the Commercial Instruction Set.  The 11/23 would accept only one of them.

> ... Also, the 11/45 and 11/55
>are more-or-less the same machine.

As is the 11/50.  The only difference is the type of memory supplied.  If I
remember correctly, the 11/45 had only Unibus memory, the 11/50 had MOS
FastBus memory, and the 11/55 had bipolar FastBus memory.  I'm still running
an 11/45 here.

>   The 11/70 is a big, nasty Unibus machine.  When I say "big and nasty",
>I'm not kidding.  The thing needs 3-phase power to run the CPU.

You AREN'T kidding!  It takes a whole BA11-K expansion box (19x22x10.5) to
hold ONE megabyte of RAM.  We've still got one of them, too.

	---Bob.
-- 
Bob Hoffman, N3CVL       {allegra, bellcore, cadre, idis, psuvax1}!pitt!hoffman
Pitt Computer Science    hoffman%pitt@relay.cs.net