Subject: Re: WinModem Driver for Linux?
From: Jeff Garzik <>
Date: Sun, 06 Jun 1999 13:33:25 -0400

Jefferson Hunt wrote:
>     With all the recent buzz about pcmcia and laptops I can't help but
> ask.  Is anyone working on hacking in support for the win modems?  If
> you want to talk about a worthless port on probably half or more of the
> laptops in service using linux that would be it.
>     Anyone know of drivers already in development?  Is there a technical
> or legal reason we can't do this?
>     I'd lend my two cents worth of coding to a project like this, so
> drop any info my way!

There is _plenty_ of interest, but no work going on at the moment.

Take a look at these two links:

Basically, winmodems contain most or all of their modem protocol logic
in the device driver (Lucent's winmodem driver is a 500K VxD!), and this
protocol logic is difficult if not impossible to get from the
manufacturers.  The protocol logic might also be patented too (I dunno
for sure), leading to additional complications.

At this point there are a couple options.

* Use existing docs (this should work for Lucent chipsets at least) and
reverse engineering tools such as the free ones at to figure out how to control the winmodem
card's DSP and codec.  This won't get you a modem, but it will get you a
driver that will let you do nifty things with phones, like voicemail. 
You can perhaps use code in the ISDN subsystem and elsewhere to
construct a simple 2400 baud modem.

* Construct a "sandbox" under which the Win95 or NT drivers may be run
under Linux.  Someone on the list mentioned that
he was working on such a beast, "WinSand."  I don't think it will work
for non-x86 processors though, since I believe it follows the same
direct execution model as WINE.

Is this question in the LKML FAQ?  :)