This article is from the Windows NT Internet FAQ, by firstname.lastname@example.org (Steve Scoggins) with numerous contributions by others.
Thanks to Christopher Browne (email@example.com) at USR for the
recommended MODEM.INF for various USR modems.
This is the .INF as we have it now. It's been tested on NT 3.1 / 3.5
andWfW 3.11 with great success. I've been able to use all of our
modems from the Courier v.34 down to the Sportster 9600 data/fax.
The MAXCONNECTBPS is set at 38400 so that this file works with most
of the installed base of modems. We only started supporting > 57600
with the Courier V.32t.
The MAXCARRIERBPS is set but any dce-dce rate that is reported at
connect isignored since the port is locked. The first release of
this file was in error since it did not contain the &B1 command
and this caused considerable pain for a few folks. My apologies!
Using ITU-T as our default allows a USR modem to connect with more
than USR modems at higher dce rates. This can be changed runtime by
the user either through the phone number "123-123-1234B0" or by
changing the INF file. I would prefer to see the phone number used
so that the modem stays in a more compatible mode by default.
; For use with Windows for Workgroups, NT 3.1, NT 3.5
; General non-connect responses that all USR modems generate...
ERROR_NO_DIALTONE=<cr><lf>NO DIAL TONE<cr><lf>
; General connect responses that all USR modems generate...
; Since serial port is locked, carrier rate is irrelevant.
; The RAS client calcuates link rate after connection is accepted.
; This selection can be used by almost ALL USRobotics modems!
; * A MAXCONNECTBPS of 38400 allows this to be used by older modems
; such as the HST 14400.
; * Compression is off by default because of the lower DTE-DCE rate.
; * ITU-T standards are on by default to ensure compatibility with
; non-USR modems.
; * X4 is set to ensure compatibility with Sportster modems. Advanced
; dial features for Courier can be activated by placing X7 in the dial
; string. (i.e. phone number field contains "1-708-676-1059X7"
; US Robotics modems are defined in original MODEM.INF are
; maintained here for installation purposes
[US Robotics Courier Dual]
[US Robotics Courier HST]
[US Robotics Courier V.32bis]
[US Robotics Sportster 2400]
[US Robotics Sportster 9600]
[US Robotics V.FC/V.34]