Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!ncar!noao!asuvax!nud!mcdchg!ddsw1!tapa!larry
From: larry@tapa.UUCP (Larry Pajakowski)
Newsgroups: comp.sys.ibm.pc
Subject: Re: 640kb limit on DOS?
Keywords: PS-2/50 DOS
Message-ID: <594@tapa.UUCP>
Date: 14 Dec 88 03:43:07 GMT
References: <8043@ihlpl.ATT.COM> <3521@nicmad.UUCP> <593@tapa.UUCP> <10687@s.ms.uky.edu> <3534@nicmad.UUCP>
Reply-To: larry@tapa.UUCP (Larry Pajakowski)
Distribution: na
Organization: Pata System Consultants
Lines: 16

Since chkdsk says I have 738k on my 386 PC let me explain.  We use QEMM.  What
QEMM does is map some extended memory above 1mb. to the space where the 640k
stops and the CGA display adapter has it's RAM memory.  These are addresses
A0000 to B7FFF.  DOS finds and uses this very nicely as part of the contiguous
memory.  As a side benefit I can load TSR's above the CGA RAM and below the
BIOS ROMS.  This space is a little more tricky to manage since things like
network adapters and LIM memory lives up there.

To do this QEMM puts the 386 into protected mode and creates a virtual 8086
machine for DOS.  DesqView expoits this by allowing you to create multiple
virtual 8086 machines much like VP/ix does under Xenix/Unix.  When running
DesqView you don't get as much memory however.

Please don't tell me anymore I can't do it because I'm it works just fine.
I like having 738k for DOS and moving my TSR's out of the lower 640!

Larry