How I got my Plug 'n' Play Modem to work with OS/2

I purchased a SupraExpress 336i PnP internal faxmodem, largely because Supra has a good 
reputation and because the price was right.  I did not intend to buy a PnP, but the retailer had no
regular Supra modems.  So I had to venture into the land of the unknown.

I should state right up front that the main idea is not mine, but I cannot properly credit it author.  I
got the idea from lurking in one of the OS2 fora on CompuServe, but I did not note who came up
with the warm reboot idea.

The basic idea is that once a PnP device is configured, as long as the power is applied, it remembers
who and where it is and its relationship to other devices.  I am not sure that the process that I went
through to arrive at a workable solution is that instructive, so I am omitting the details.

First, I booted to DOS.  The Supra modem comes with a disk called the Legacy Install Disk.  It is key.
Without it, only a PnP operating system can use the modem, and DOS surely isn't one.  I followed the
instructions and installed the necessary software.  I then installed the Supra WinICU Diagnostic Disk.
This file has the Intel Configuration Utility, which allows the PnP system to be simulated in DOS.  It
creates a reference file, ESCD.RF, in the root of the boot drive and adds this line to CONFIG.SYS:

        DEVICE=C:\SUPRA\DWCFGMG.SYS

Now the modem can work with DOS.  I do not know if one could do this installation from a DOS
session in OS/2, but I usually install DOS devices in native DOS, just to avoid problems.

To get this system to work with OS/2, I had to do three things.  One, I had to state explicitly on the
COM.SYS device call in the OS/2 CONFIG.SYS to what COM port, address, and IRQ that the modem
was assigned.  Of course, this meant I had to get the information from the ICU program.  As expected
in my setup, I got the normal COM2 assignments.  Without the explicit statement, the COM.SYS and
VCOM.SYS would not load, presumably because there seemingly no device for them to control.  Two,
I had to create a DOS batch file, in which I used the DOS settings (DEVICE) to call the needed device
file, which is the same as the indented line above.  Without it, the PnP device has nothing with 
which to configure itself.  I put this batch file, which simply writes a sentence to the screen and
then closes, into the STARTUP folder.  Third, I had to put the ESCD.RF file in the root of the OS/2 
boot disk, so that DWCFGMC.SYS could find the configuration information.  This means that I have 
two copies, one on my DOS boot disk and one on my OS/2 boot disk and I have to manually make 
sure that they stay in sync.  It might be possible to use a shadow of the DOS boot disk file on the 
OS/2 boot disk, but I decided to keep it this way for flexibility.

Once that was done, I could use my PnP modem with OS/2, without having to first boot DOS and
then warm booting into OS/2.

Submitted by Mark Ensminger.  If you have questions, I can be reached at
76436.2305@compuserve.com   Please note that I am no expert at this stuff.  I just happened to run
across a good idea and found a way to adapt it to my needs.  So I won't promise that I can help.