Linmodems First Steps Beginner's Guide

Reminder: do not waste your time here if your modem is not internal, USB or PCMCIA.

If you read this page under Windows, read this now!

In order to use the information available on this site, the first thing to do is to determine the following information, keep it available at all times, and include it in any query sent to the discussion list.

  1. Which Linux distribution are you using? That's where you installed your Linux system from, for example RedHat 6.1 or Mandrake 8, or whatever. The required information includes the name of the distributor and the releasenumber.
  2. Which Linux kernel are you running? The Linux command uname -r shows this.
  3. Which brand and model of modem is there in your machine?
    You should always begin by running the scanModem utility.
    Otherwise, if you wish you may trust the seller. Only (not laptops) if your computer can easily be opened, you can read off the card. Or, if you also have Windows on your machine, access "Control Panel" then "System", select "Device Manager", click on + to the left of "Modem", click on the name of the modem, and then click "Properties"; write down the name of the modem, the "Resources" which Windows (Windows, not the BIOS, remember this) allocated to it, and the "Driver File Details" under "Driver". If you cannot use any of these methods (again, do not try to destroy your computer to look into its guts), leave this information unknown and go to next item.
  4. Which bus is used by your modem? Modems can be PCMCIA ("Credit Card" plug in), older ISA technology, or more recent PCI technology. If it is a removable Credit Card size modem, then you know it is PCMCIA, otherwise try PCI, and if none found then try ISA. If you do not find any PCMCIA, PCI or ISA modem, check if some external modem hangs around the box, or see your dealer.
  5. Which chipset is used in your PCI modem? The Linux command cat /proc/pci will show a "Communication controller" section. Note down the hexadecimal codes for Vendor ID and Device ID.
    Or under Windows, download shareware PCITree.Unzip run, set cursor on the Communications controller line.
  6. Which chipset is used in your ISA modem? The Linux command /sbin/pnpdump will show your card and its Vendor and Device ID's.
  7. Which chipset is used in your PCMCIA modem? With the card inserted (!!!), the Linux command /sbin/cardctl ident shows the ID's in the manfid line.
  8. It is also possible to determine these parameters under Windows using the utility ListMdm available on the Conexant Web site, click on Customer-Center, then Modem-Support, then Modem-Driver-Assistance, then "Agree" and browse the page. It reports the chip vendor Id and chip Id for any modem, not necessarily Conexant.
  9. What is the Chipset manufacturer? All chances are that you quickly can now searching for vendor device with the superb Google search engine, typing the actual vendor Id, not the word vendor, and the actual device Id, not the word device, in the Google search window. Or search in PCI information listings


For my portable:
Distribution: RedHat 6.1
Kernel: 2.2.12-20
Modem: PCI ActionTec 56k Pro
Chipset: vendor 11c1 device 448
Chipset manufacturer: AT&T, then Lucent, now Aegere.

You can now return to the main page, to find out whether your modem is supported under Linux.


For some Linux distributions, lspci -v or -vv does not show chip details.
In such a case, give the following three commands:
/sbin/lspci > junk ; echo "-------" >> junk ; /sbin/lspci -n >> junk
This creates file "junk" with two parts separated by -------
Find your modem in clear text of part 1. Use the index string in first field to find the index matching line in part 2. Read off Vendor_Id:Device_Id at the end of this line (ignoring optional revision number, of course).
The name of the file is intended to remind you to "rm junk" when you are done.
Chris Hebeisen knows how to do all this in one smart line:
/sbin/lspci -n -s`/sbin/lspci | grep -i communication | cut -d" " -f1`
assuming that the modem is shown as Communications controller which may not always be true. To use Chris's line, better cut/paste than type ...

Page made by Jacques Goldberg, Department of Physics, Technion, Haifa, Israel
Last updated: Tue Jul 24 11:59:58 IDT 2001