Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!uunet!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Motorola 68851 PMMU discontinued
Message-ID: <8299@cbmvax.UUCP>
Date: 26 Oct 89 21:10:14 GMT
References: <1077@odin.SGI.COM>
Organization: Commodore Technology, West Chester, PA
Lines: 24

in article <1077@odin.SGI.COM>, pkr@maddog.sgi.com (Phil Ronzone) says:

> In article <3360@netcom.UUCP> wasilko@netcom.UUCP (Jeff Wasilko) writes:

>>Is Sun still shipping Sun 3/60s?
>>I would assume that they need PMMUS to run unix...

> No, the SUN 3 uses a discrete logic MMU. 

So do the Apollos, far as I know (though I've never looked at the newer '020
based desktop models).  The Amiga 2500 includes the 68851, and I'd certainly 
think other machines would too.  Though Motorola was so late with '851, it's
not surprising that many '020 machines use hand-made MMUs.  At Commmodore, we
had even started working on our own VLSI MMU, but Motorola came though just 
in time.  So while I'd be surprised to believe Moto's cancelled the '851, the
cost factors are already in the favor of the '030, and replacing an '020/'851
with an '030 is a lazy afternoon's work in most systems.

> Phil Ronzone   Manager Secure UNIX           pkr@sgi.COM   {decwrl,sun}!sgi!pkr

-- 
Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
                    Too much of everything is just enough