Path: utzoo!utgpu!cunews!bnrgate!bwdls61.bnr.ca!bwdls58!mlord
From: mlord@bwdls58.bnr.ca (Mark Lord)
Newsgroups: comp.sys.ibm.pc.misc
Subject: Re: EMS hardware vs. software emulation
Message-ID: <5182@bwdls58.UUCP>
Date: 8 Jan 91 17:41:31 GMT
References: <37694@cup.portal.com>
Sender: mlord@bwdls58.UUCP
Reply-To: mlord@bwdls58.bnr.ca (Mark Lord)
Organization: Bell-Northern Research, Ottawa, Canada
Lines: 24

In article <37694@cup.portal.com> mmm@cup.portal.com (Mark Robert Thorson) writes:
<It seems to me that anyone who designs a system with a 286, 386, or 486
<with more than 1M of memory should include hardware EMS registers and mapping
<logic, unless he only plans to run Unix.  At first, I thought maybe only
<the 286 needs it, because the other chips have paging.  But then I remembered
<that all the DOS people run in real-address mode, so the paging mechanism
<is disabled.  The only way around this would be to run your DOS applications
<in virtual-8086 mode, but I don't think anybody does that, do they?

Thousands and thousands of us do this all of the time, with no problems other
than slightly greater interrupt latencies due to the V86 mode.

How, you ask?  

We run QEMM386, or 386^MAX, or EMM386.SYS, or..

And with far greater flexibility than specialized EMS hardware could possibly
provide.  Especially with things like QEMM, which support ALL past/current
memory standards simultaneously:  VCPI, DPMI, LIM3.2, EMS4.0, XMS ...     
-- 
 ___Mark S. Lord__________________________________________
| ..uunet!bnrgate!mlord%bmerh724 | Climb Free Or Die (NH) |
| MLORD@BNR.CA   Ottawa, Ontario | Personal views only.   |
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