Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!wuarchive!mit-eddie!uw-beaver!cornell!vax5.cit.cornell.edu!hd7x
From: hd7x@vax5.cit.cornell.edu (Sanjay Aiyagari)
Newsgroups: comp.os.msdos.misc
Subject: Re: DOS 4.01 Device Drivers
Message-ID: <1990Dec11.025410.1522@vax5.cit.cornell.edu>
Date: 11 Dec 90 06:54:09 GMT
References: <77533@iuvax.cs.indiana.edu>
Distribution: comp
Lines: 36

In article <77533@iuvax.cs.indiana.edu>,
rschmidt@copper.ucs.indiana.edu (Roy Schmidt) writes:
> It seems that there are two device drivers in my MSDOS 4.01 package that
> are not documented.  I had not given much thought to these two because
[... deleted ...]
> EMM386 only activated 640K of LIM 4.0 Expanded Memory.  It also gave me
> a message saying that fact.  I examined this with PCTOOLS and found that
> over 3 MB of Extended Memory was there and *not* accessible.  Further,
> PCTOOLS thumbed its nose at the 640K of Expanded Memory and didn't use
> any of it to store its overlays as advertised.
>
> HIMEM grabbed 64K of RAM from limbo land (between 640 and 1024) and
> stored part of DOS and all the other device drivers (mouse, ansi, etc.)
> up there.  They all function just fine, and DOS is trimmed to 73K (still
> a little fat, but I can wait for 5.0).
>
> Now, so much for jabbering -- just wanted everyone to understand that
> the things work, and I basically know what I am doing.  My problem is
> that I don't have any documentation for these two drivers.  I went thru
> the manuals every which way and they are not there!  Is anyone familiar
> with these two drivers?  Are there switches to control such things as
> how much Expanded Memory gets turned on (EMM386) or how much limbo room
> is stuffed with DOS?

The documentation for these two drivers is in Appendix D of the Microsoft
Windows 3.0 manual.  EMM386 needs a parameter to indicate how much EMS to use.
It doesn't automatically convert all extended to expanded the way QEMM does.
To solve this problem, simply use the line:
device=emm386.sys 3072
And you'll have 3 MB EMS.  There is also a frame= parameter to specify the
location of the EMS page frame, but it usually is not necessary.

As for HIMEM.SYS, there isn't much to it other than the device=himem.sys.  The
only interesting parameter is the /shadow:off parameter to disable shadow RAM,
but since you have 4 MB I don't think you'd want to do that.
Sanjay Aiyagari (hd7x@vax5.cit.cornell.edu)