Date: Thu, 6 Jul 2000 9:19:44 GMT
From: aven AT ukgateway DOT net (Alex Venn)
Organization: Computer Peasant
Message-ID: <200076.12673ba$@ukgateway.net>
To: opendos AT delorie DOT com
Subject: DR-DOS upper memory problem
X-Mailer: OLIM 1.38
Lines: 22
Reply-To: opendos AT delorie DOT com

I've been using an old Packard Bell 486 and have come across a weird
memory instability which suggests that in some circumstances the DR-DOS
EMM386 can be unreliable in it's tests for ROM areas. Every so often I
experienced a lot of EMM386 errors and crashes, while at other times the
same mix of programs was stable. Eventually I discovered that sometimes
EMM386 saw the whole of the upper memory area from 768k to 1Mb as RAM
and claimed to have stuck data where the video and system ROM was
supposed to be.
Eventually I used the ROM option to shadow the ROM areas identified by
MFT and since then not a crash (AUTO also appeared to be inconsistent).
I can't say how common a problem this is, but it may be one explanation 
for some of the reported instability of the DR-DOS EMM386.

The only question I now have is, how reliable a memory mapper is MFT ? 
Also, is there a better or free alternative ? (or are QEMM and DV really
free nowadays ?)

Alex.
-- 
   ____________________________    _______________________________
  (    Alex Venn               )  (   Success has many fathers,   )  
 (_)   aven AT ukgateway DOT net     (____)  but failure is an orphan.  (_)