Re: Multiple device files for multiple modems

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This is an issue explored long ago.
For Controller Chipset (hardware) modems, all of the signal processing
occurs on the modem card with each having its own port/device and no
deleterious overlap of functionality in the CPU.  Thus multiple
hardware modems can be serviced on a single PC.

However the so called softmodems (which you likely have) were designed
as cheap consumer devices, and the supporting software was NOT written
with sophistication to maintain separate data streams in the CPU,
which does carry increasing amounts of the signal processing in the
AC'97 modem family, and almost all the processing for the more current
family of modem chips hosted on High Definition Audio cards.  For
these modems, the modem hardware has two major roles:
1) providing the physical interface to the phone line
2) specify the software package to be used under Microsoft.

A few members of this List wrote additional software to create
separate ports for multiple Lucent/Agere modem cards, but this alone
proved to be inadequate.
The precompiled ltmdmobj.o component of the code (which we could not modify)
just did not maintain separate data streams during concurrent modem usage.

Our contacts at Lucent/Agere recommended that for reliable service,
it was indeed necessary to use hardware modems.

scanModem maintainer

On Fri, Nov 4, 2011 at 6:52 PM, Jason Flatt <jason@xxxxxxxxxxxxxxxx> wrote:
> Hello all.
> I have a computer that I'm setting up as a fax server, and I've installed two
> US Robotics PCI Express modems (they use the Agere Systems chip set) in it.
> Both devices work fine separately.  The system recognizes them, creates the
> device file and symbolic link.  setserial, wvdial, and minicom all work with
> both of them.
> The problem I have is that only one device file is created, so I cannot use
> the two of them simultaneously.
> I have searched the Internet, and especially the archives for this list to no
> avail.  Apparently, no one ever installs two of these devices into the same
> computer (or I don't know how to search, which is also entirely likely).
> So, my question is, how do I get a second device file created, or create one
> myself, that will allow the two modems to operate at the same time in the one
> computer?
> Thank you.
> --
> Jason Flatt
> Computer and network service and support:
> Father of seven: (Joseph, 18; Cramer, 16; Travis,
> 14; Angela; Harry, 11; William, 5; and Dolly, 3) Linux user:
> Drupal fanatic:

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