From: MORRIS JP <jpmorris AT csm DOT uwe DOT ac DOT uk>
Date: Wed, 29 Jan 1997 10:39:16 GMT
Message-Id: <199701291039.KAA04810@milly>
To: jdashiel AT eagle1 DOT eaglenet DOT com
Subject: Re: [opendos] EMM386 gets violent - solution!!!
Cc: geneb AT web DOT wa DOT net, jamesl AT mail DOT albany DOT net, opendos AT mail DOT tacoma DOT net
Sender: owner-opendos AT mail DOT tacoma DOT net
Precedence: bulk


I may have the solution.  This worked for me, anyway....

There is a hidden switch in EMM386 which I only discovered after some searching
at 2AM.

If you run EMM386 /? from the dos prompt, it will tell you about the PIC=
switch.  Read this, it is quite interesting..

What you must do is run 'EMM386 PIC=ON' from the DOS prompt, and this will fix
most problems.

(There is one problem left, but I have only found one program that is affected,
 but this might be a latent bug in my code.
 After it finishes, the CPU speed goes down to 10 mips (from 31)....)

Unfortunately, the PIC switch is not accessable when EMM386 is installed as a
device.  This means that to make it work properly, you must put it in your
AUTOEXEC.BAT file.

It might be as well if in future releases of OpenDOS, PIC=ON was the default,
as it will save a lot of hassle and unexplained crashes.

I have not yet tried running programs that use high interrupt frequencies
of > 8Khz, this could prove interesting.

There may still be bugs in EMM386's pic handlers when running on nonstandard
processors (Cyrix, AMD), this should be investigated when possible.

Good luck, everyone!