Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!apple!vsi1!wyse!mips!rogerk
From: rogerk@mips.COM (Roger B.A. Klorese)
Newsgroups: comp.arch
Subject: Re:  Re: MicroVAX emulation
Message-ID: <15665@winchester.mips.COM>
Date: 21 Mar 89 20:39:41 GMT
References: <807@microsoft.UUCP> <92634@sun.uucp> <13322@steinmetz.ge.com> <1133@auspex.UUCP> <12000@haddock.ima.isc.com> <1368@husc6.harvard.edu> <679@scaup.cl.cam.ac.uk> <12035@haddock.ima.isc.com> <687@scaup.cl.cam.ac.uk> <37515@bbn.COM>
Reply-To: rogerk@mips.COM (Roger B.A. Klorese)
Organization: MIPS Computer Systems, Sunnyvale, CA
Lines: 28

In article <37515@bbn.COM> slackey@BBN.COM (Stan Lackey) writes:
>The MICROvax architecture does NOT include
>string instructions, other than MOVC3 (and MOVC5?).  Some DEC-supplied
>software includes emulation to ease the transition.  Generating the
>in-line emulation using a reduced instruction set is NO PROBLEM, right?

There *IS NO* MicroVAX architecture.  There is a MicroVAX *implementation*
of the VAX architecture, which implements some instructions in software.
This is very different.

>1.  The uVAX is NOT said to implement the VAX architecture.

I've never seen this claimed.

>2.  MIPS, AMD, Intel, Motorola, Sun, etc. don't do your work for you either.
>    I don't understand why it is OK for the RISC suppliers to supply
>    reduced instruction sets, but if DEC does it it's evil.

Ours is not "reduced" as in an incompatible subset of our other products.
Our *architecture* is designed around instruction leanness.  If we were to
release a system on which some of our instructions would not run in either
hardware or provided software, that would not be reduced, that would be
STUPID.
-- 
Roger B.A. Klorese                                  MIPS Computer Systems, Inc.
{ames,decwrl,pyramid}!mips!rogerk      928 E. Arques Ave.  Sunnyvale, CA  94086
rogerk@servitude.mips.COM (rogerk%mips.COM@ames.arc.nasa.gov)   +1 408 991-7802
"Committing a gross indecency shows you do things in a big way." - J. Broughton