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  Sean Walbran sean(at) and Marvin Stodolsky
  v0.43, 24 February 2001

  This document describes Linmodem (winmodem hardware) support under
  Linux.  While such support is limited (almost exclusively in the form
  of manufacturer-created, but unsupported, binary kernel modules), the
  number of chipsets with some form of support is growing rapidly.

  Table of Contents

  1. Introduction

     1.1 Copyright
     1.2 Disclaimer
     1.3 Credits
     1.4 Updates and Corrections

  2. Linmodems

     2.1 What is a Linmodem?
     2.2 Which Linmodem hardware is supported?
     2.3 How can I find out if my GeeWhiz 9.8.7 Modem / Laptop has one of these chipsets?
        2.3.1 Information from the system
        2.3.2 Modem names and identification numbers
        2.3.3 Laptops with internal modems

  3. General Setup and Kernel Module Issues

     3.1 Kernel Module Support
     3.2 ISA Plug-n-Play
     3.3 PCI Modems
     3.4 Module tools
        3.4.1 insmod, insmod -f, and modprobe
        3.4.2 rmmod
        3.4.3 depmod

  4. Tips and Tricks for Precompiled Modules with different Kernel Versions

     4.1 Fixscripting
     4.2 Patching
     4.3 Using a

  5. Specific Chipsets and Their Drivers

     5.1 IBM Mwave (Thinkpad 600E)
     5.2 Lucent LT
        5.2.1 Overview
        5.2.2 Driver v5.78(c,d,e,...) - Installation
        5.2.3 Manufacturer's driver version 5.68 - Installation
        5.2.4 Open Source Tools - Installation
     5.3 ESS
        5.3.1 Overview
        5.3.2 Installation
     5.4 PCTel
        5.4.1 Overview
        5.4.2 Installation
     5.5 Conexant/Rockwell HSF
     5.6 Intel (formerly Ambient Technology, formerly Cirrus Logic)
     5.7 3Com
        5.7.1 56k
        5.7.2 Mini-PCI
     5.8 AMR

  6. Troubleshooting

  7. FAQ

     7.1 I have a winmodem.  Will it work under Linux?
     7.2 I get "NO DIALTONE".
     7.3 I get a "device or resource busy" error.
     7.4 I get unresolved symbols when fixscripting/insmoding.
     7.5 My PCTel modem doesn't work.
     7.6 The modem dials and connects fine, but then it drops the connection.
     7.7 I get a kernel panic on closing the connection or unloading the driver.
     7.8 Nothing seems to work.  To whom can I turn for help?
     7.9 Who wrote the driver for my winmodem, and how do I contact him/her?
  8. Appendix

     8.1 PCTel Module Parameters:  Country Code


  1.  Introduction

  This is the Linux Linmodem HOWTO document. It is intended as a quick
  reference to help you find out if there is a way to get your (so-
  called) winmodem working under Linux, and, if so, how to do it.  You
  should understand from the outset that there may well be no support
  for your winmodem: there is limited support for such modems, often in
  the form of vendor-created but vendor-unsupported, binary-only kernel
  modules (though a small number of open-source projects exist).

  To emphasize: your best bet under Linux is certainly to get a true
  hardware modem.  However, if you're stuck with a winmodem, perhaps
  this document can help.

  For the most up-to-date information about available Linmodem drivers,
  visit Rob Clark's site
  <>, our small
  resources page <>, and the mailing list archives <
  bin/ezmlm-cgi/1>.  General modem issues, such as IRQ settings and
  dialup scripts, are dealt with much more thoroughly in the more
  general Modem-HOWTO <>,
  Serial-HOWTO <>, PPP-
  HOWTO <>, and other
  related HOWTOs available at the Linux Documentation Project
  <> site and elsewhere.

  1.1.  Copyright

  Copyright (c) 2000,2001 by Sean Walbran, Marvin Stodolsky

  Please freely copy and distribute (sell or give away) this document in
  any format.  It's requested that corrections and/or comments be
  fowarded to the document maintainer. You may create a derivative work
  and distribute it provided that you:

  �  Send your derivative work (in the most suitable format such as
     sgml) to the LDP (Linux Documentation Project) or the like for
     posting on the Internet.  If not the LDP, then let the LDP know
     where it is available.

  �  License the derivative work with this same license or use GPL.
     Include a copyright notice and at least a pointer to the license

  �  Give due credit to previous authors and major contributors.

  If you're considering making a derived work other than a translation,
  it's requested that you discuss your plans with the current

  1.2.  Disclaimer

  Use the information in this document at your own risk. We disavow any
  potential liability for the contents of this document. Use of the
  concepts, examples, and/or other content of this document is entirely
  at your own risk.

  All copyrights are owned by their owners, unless specifically noted
  otherwise.  Use of a term in this document should not be regarded as
  affecting the validity of any trademark or service mark.  In
  particular, since the term "Winmodem" is a trademark of US
  Robotics/3Com, we use the term "winmodem" here as does Rob Clark: to
  be read as "Winmodems(tm), host-based modems, HCF-modems, HSP-modems,
  and all similar modem-like hardware."  Linux is a trademark of Linus

  Naming of particular products or brands should not be seen as

  It are strongly recommended to make a backup of important and/or
  relevant files before any installation procedure.

  1.3.  Credits

  Most individual credits are given in the body of the text where

  A large amount of information contained in this document comes a
  variety of great sources such as Rob Clark's site
  <>, the
  <>, mailing lists, and Werner Heuser's
  Mobilix <> pages.

  Special thanks to Mark Spieth (mark(at) for
  discussions, advice, and multiple and ongoing contributions.

  This document itself was created using the SGML HOWTO template created
  by Stein Gojen, as described in the HOWTO-HOWTO
  <>.  site.

  1.4.  Updates and Corrections

  The most recent HTML version of this document is available at
  <>, as a single HTML
  file at <>, with
  source SGML at  <>.

  The old version of this document was getting huge and unwieldy, so
  this rewrite seemed necessary.  To avoid the total loss of that
  information, a copy of the old version is maintained at

  Do you have a Linmodem which works, but is not described here?  Are
  you developing a driver?  Do you think something in this document is
  incorrect or misleading?  Do you think that your or someone else's
  work has been used here but not appropriately credited?  Please don't
  hesitate to email me at sean(at) with corrections and

  2.  Linmodems

  2.1.  What is a Linmodem?

  A Linmodem is the Linux implementation of a "winmodem" (see
  disclaimer).  These devices are 'less than' a modem in the sense that
  they depend on software to perform, to a greater or lesser extent, the
  functions traditionally handled by modem hardware.  The rationale for
  this is, of course, that software is cheaper than hardware, and can be
  upgraded/expanded/improved without the use of screwdrivers (usually);
  however, for the modem to function at all, one requires software that
  can run on one's preferred operating system.

  2.2.  Which Linmodem hardware is supported?

  An ever-growing number of winmodems will work under Linux.  Each
  chipset for which a driver is known to exist has a section in this
  document, below, describing its installation.  Any other chipset has
  no known support under Linux (at least, not known to us).

  2.3.  How can I find out if my GeeWhiz 9.8.7 Modem / Laptop has one of
  these chipsets?

  2.3.1.  Information from the system

  The information about installed hardware using commands such as:

  �  PCI:  cat /proc/pci  and  lspci

  �  ISA:  pnpdump  and  isapnp

  �  Internal PCMCIA:  cardctl ident

  �  General:  dmesg | more  and  cat /proc/interrupts

  MarvS notes that the Device Manager under Windows can provide similar
  information, but it should be noted that a manufacturer will often
  simply put its brand name on a built-in modem, so this information may
  not be as useful as you might hope (e.g., what chipset does a "Compaq
  Internal 56k" modem have?).  Additional information may sometimes be
  obtained by making a modem log, implemented under MS Windows as a
  check box option within the Dial Up Networking menus.  The file
  produced is C:\WINDOWS\MODEM.LOG.  It will contain the modem
  initialization strings, and perhaps also the name of the modem
  configuration file, which may also contain other useful information.

  2.3.2.  Modem names and identification numbers

  If you know the precise name of your modem, you can try searching the
  large Linux Modem Compatibility Database
  <> at Rob Clark's
  site <>.  The color/letter
  code on the left side of the table will indicate if your modem is
  known to function or not under Linux.  The code "LM" indicates a
  Linmodem, and the modem notes should indicate which driver you need.
  A "WM" means it's a winmodem, but no Linux support is known to exist.
  Be careful not to assume that modems with similar names will contain
  the same chipsets, or will necessarily behave similarly whatsoever!
  Your WhizBang LX56 and your friend's WhizBang GT56 could have entirely
  different innards.

  If you do not know the precise name of your modem, you can search
  based on the identification number of the modem ( on every modem there
  must be printed a registration number, which may either be the board
  producer's designation, or, alternatively, an FCC registration number.
  An example photo of such an ID number on a modem board can be found at
  <> on Rob Clark's site
  <>.)  Use your web
  browser's "Find in Page" to search his table
  <> of modems and
  FCC ID's to obtain chipset/driver information.  Alternatively, you can
  directly search the US Federal Communications Commission (FCC)
  database at <>.  Read the directions
  carefully, and be careful not to confuse O (the letter) with 0 (the
  number), and other possible mixups.

  2.3.3.  Laptops with internal modems

  You may not be able to obtain the FCC ID number if you have a laptop
  which you prefer not to open up, or are looking to buy a particular
  machine and the vendor has not been polite enough to provide you with
  the information nor a sample box for you to take apart and play with.
  In these cases, you might try:

  �  Kenneth Harker's Linux on Laptops
     <> site indexes
     a large number of user-created sites describing their experiences
     with Linux on particular laptop models.

  �  Werner Heuser's Mobilix: Linux Modems
     <> and Mobilix: Linux Mini-PCI
     <> pages include lists of
     specifications for laptops with internal modems and NIC's, as well
     as useful tips for obtaining more information in case the model is
     not listed there.

  �  The computer vendor's manual, web site, or (horrors!) technical

  �  <>

  3.  General Setup and Kernel Module Issues

  3.1.  Kernel Module Support

  All of the kernel drivers listed here are released as kernel modules;
  therefore, you must be sure to have a kernel which supports modules.
  In addition, "module version" support should be enabled to aid the use
  of kernels and modules which are not version matched, as described
  further below.  If you use a kernel from a reasonably recent Linux
  distribution, such module support is most likely already enabled.  If
  you're compiling the kernel yourself, then you should already be aware
  of how to enable modules, via the Kernel HOWTO
  <>.  In any case, you
  can check to make sure that the following settings exist in your
  kernel configuration  file (which is usually found under


  3.2.  ISA Plug-n-Play

  If you have an ISA Plug-n-Play modem, you will most likely need to use
  isapnptools to allocate resources to the modem card.  For this, you
  need to have isapnptools installed and have an entry in the
  /etc/isapnp.conf file for the modem.  You should read the manual pages
  and the Plug-and-Play-HOWTO <
  Play-HOWTO.html>, but if you have no other ISA devices you're
  concerned about, basically all you need to do is:

  1. If possible, configure your BIOS to "Non-PNP OS."

  2. As root, run pnpdump to generate a prototype isapnp.conf file based
     on probed cards and your system's current resource usage.

  3. Look for your modem in this output, and uncomment the lines
     corresponding to the (otherwise unused) IRQ you wish to use for the
     modem.  For example, Sean's isapnp.conf for a Thinkpad i1411 with a
     Lucent LT modem includes:

     (CONFIGURE ACRd119/1 (LD 0
       (INT 0 (IRQ 11 (MODE +E)))
       (IO 1 (SIZE 8) (BASE 0x0100) (CHECK))
       (NAME "ACRd119/1[0]{LT Win Modem        }")
     # (ACT Y)

  Strangely, in this case at least, it was necessary to leave the #(ACT
  Y) commented out.  If it doesn't work for you one way, try it the

  4. Copy the file to /etc/isapnp.conf

  5. Reboot.  You should see a message along the lines of 'Initializing
     ISA PNP devices...OK' on booting.  If it fails, you have probably
     selected an IRQ/DMA setting which is already in use; try another of
     the options given in the pnpdump output.  (Note that it is probably
     not necessary to reboot, if you run isapnp with the right flags.
     However, it's easiest for the beginner to simply reboot at this

  3.3.  PCI Modems

  If you wish to know more about your PCI modem than cat /proc/pci
  gives, utilities within the software package pciutils are useful, such
  as scanpci and lspci.  In particular, lspci -vv gives lots of nice,
  useful information.

  3.4.  Module tools

  The following commands are useful when dealing with modules.  Many
  require root priveleges.  See the manual pages (e.g., man insmod) for
  more detailed information on these commands.

  3.4.1.  insmod, insmod -f, and modprobe

  A version-matched kernel module should usually be inserted using the
  command modprobe module_name; modprobe will try to insert any other
  modules on which your module depends (as determined by depmod,
  described below).

  A single module can be inserted (without those modules on which it
  depends) using the command insmod module_name.  If the module were
  compiled under a different kernel than the current one, insmod would
  report the version mismatch and refuse load the module.  One can,
  however, pass a flag to force the module to load despite the mismatch:
  insmod -f module_name.  If the kernel interface the module uses did
  not actually change with the kernel version, the module will be
  inserted and could be to some degree functional.

  This is the case with, for example, the ESS modem module esscom.o
  which, while compiled under 2.2.12, can be forcibly inserted with
  later kernels and will function to a greater or lesser extent up
  through kernel version 2.2.14 without further changes; beyond 2.2.15,
  the patch to tty.h described below is required.  However, even forcing
  insertion fails for kernels from the 2.4 series.

  3.4.2.  rmmod

  A module can be unloaded (removed from the kernel) after use by
  issuing the command rmmod.

  3.4.3.  depmod

  The depmod commands analyzes module dependencies.  The compatility of
  precompiled modules with a running kernel can be checked with a
  command like:

     depmod -e ltmodem.o

  For the specific example of the ltmodem.o module compiled under kernel
  2.2.12 with a running kernel 2.2.17, the returned information

  �  depmod: *** Unresolved symbols in ltmodem.o

  �  depmod:        bh_mask

  �  depmod:        schedule_timeout

  �  depmod:        request_region

  �  depmod:        pcibios_read_co

  �  and many others.

     Using a module with unresolved symbols can be a dangerous thing, as
     described below.

  4.  Tips and Tricks for Precompiled Modules with different Kernel Ver�

  Many of the linmodem drivers are only available as precompiled, binary
  kernel modules.  Generally, modules/binaries transparently function
  only with the kernel against which they were co-compiled.  Therefore,
  getting a precompiled linmodem driver to work with your particular
  kernel could be a challenge.

  Since the Linux kernel is a dynamically changing beast, it is very
  unfortunate that many modem/chip vendors have not yet chosen to
  release source-code versions of their drivers, which would ensure your
  and our ability to modify these drivers appropriately as kernel source
  code evolves.  Some of the binary modules have been coaxed to function
  under some later kernel versions using various tricks, as described
  below; however, even though a module may be rendered functional, it is
  advisable to use them minimally.  Quoting an email from Mark Spieth,

  "A driver can never work properly if there are unresolved symbols, as
  it means something is not going to work. Furthermore, it means that
  that something that would have been called will call something else in
  the kernel and this could be anything. This is very bad."

  Therefore, you should be careful in using binary modules with a kernel
  of a different version; proceed at your own risk.  If you require
  above all that your modem function, consider downgrading your kernel
  to match the module - this is by no means a ridiculous prospect.
  Despite these warnings, however, many others have used mismatched
  binary modules and kernels with only minor annoyances ( such as the
  occasional kernel panic ) using tricks and tools such as the

  4.1.  Fixscripting

  Mark Spieth has contributed a progressively improved series of
  "fixscripts" for editing a binary module so that version mismatch
  warnings are eliminated.  Insertion of the "fixed" module then
  proceeds without the forcing flag, i.e. simply insmod module_name.
  Later versions also rename module symbols to match those exported by
  the kernel, so that "Unresolved symbols" errors are not returned by
  the test depmod -e.  It must be emphasized that this change is almost
  entirely cosmetic - it is still recommended that the module be used

  To use the fixscript on, for example, the (now-deprecated) binary
  Lucent module ltmodem.o, make a working directory such as /root/modem.
  Obtain the latest fixscript from
  <>.  Save the file as
  fixscript.  View it with less or your favorite text editor to check
  that DOS hard stops were not accidentally acquired. They look like
  bold M, underlined M, or ^M depending upon your viewer/editor. NOTE:
  the viewer more does NOT display these DOS newlines.

  Make the file  executable with chmod +x fixscript.  Generate a "fixed"
  module with, i.e.,

      ./fixscript ltmodem.o ltmodem2217.o

  No errors should be generated by testing the module dependencies with

      depmod -e ltmodem2217.o

  and insertion should succeed with a simple, non-forced,

      insmod ltmodem2217.o

  The "source code" supplied with some PCTel modules (a small C file)
  performs similar masquerading when compiled and linked with the binary
  libraries in those packages; unlike the partially-open-source Lucent
  driver, it does not compensate for any actual changes to the kernel

  4.2.  Patching tty.h

  In his quest to get the original, binary-only Lucent LT modem driver
  (version 5.68) working with kernels later than 2.2.14, Mark Spieth
  noticed that one simple change in the Linux kernel source fixed the
  major incompatibilities incurred between the 2.2.14 to 2.2.16 kernel
  versions.  This patch is no longer necessary when using the partial
  source/binary Lucent driver (version 5.78), but it remains useful for
  those with other modems whose drivers are compiled against pre-2.2.15

  The patched 2.2.17 tty.h and some 2.2.17 kernel packages compiled with
  this patch are available from
  <>.  If you want to do the edit
  yourself, the line to shift is in the structure tty_struct within
  include/linux/tty.h; it has an extra member poll_wait in later
  kernels.  Move this member to the bottom of the structure, so that the
  remaining offsets will then be the same as those in versions earlier
  than 2.2.15, and thus be compatible with the precompiled kernel
  module.  You will need to recompile your kernel and modules after
  making this change to the source.

  4.3.  Using a ppp.o  from Kernel 2.2.14

  A trick exists for using the binary modules with kernels later than
  2.2.15 which does not require kernel recompilation; however, following
  the discovery of the tty.h patch described above, this trick is no
  longer necessary nor recommended.  The trick is to replace the
  /lib/modules/net/ppp.o module with one from kernel 2.2.14.   Christoph
  Hebeisen (cth(at) reported that the use of ppp.o version 2.2.14
  rather than that of version 2.2.16 with the Lucent module provided
  functionality under 2.2.16 kernels.    Willie Green
  (willjr(at) confirmed that this trick works also with the ESS
  module. After simple insertion of a supporting version-matched module:

      insmod slhc

  the mismatched ppp.o from 2.2.14 source is inserted

      insmod -f ppp.o

  We wish to emphasize that this trick with forced insertion is less
  stable than the easy and more effective change to the kernel source
  file tty.h, as described above.

  5.  Specific Chipsets and Their Drivers

  5.1.  IBM Mwave (Thinkpad 600E)

  IBM has a completely open-source (GPL'ed) driver for the software
  modem in their Thinkpad 600E's available here

  5.2.  Lucent LT

  5.2.1.  Overview

  This modem enjoys the most support under Linux, in that there exist
  three different driver packages:

  �  There exists a manufacturer-unsupported, half-binary/half-open-
     sourced kernel module, originally designed for Red Hat 6.2's
     2.2.14-5 kernel, but substantially reworked by Mark Spieth and
     others to function with 2.2.x and 2.4.x kernels.  This is driver
     version 5.78(c,d,e,...), and is the driver you are most likely to
     have success using.

  �  There exists a manufacturer-unsupported, binary-only kernel module,
     compiled under Red Hat 6.0's 2.2.12-20 kernel.  This is driver
     version 5.68.

  �  Some open source tools for use with Lucent modems are available at
     <>.  Pavel Machek writes
     that "It is not too useful, however: it is a hardware driver, and
     without a v.34 protocol stack, you can't connect to your ISP. It is
     enough to turn your Lucent winmodem into an answering machine,

     It should be noted that the binary-only driver module (from
     "") contains code from the  GPL'ed Linux serial.c
     driver, so, since the source code for the modem driver is not
     available, trafficking in this driver is apparently in violation of
     the GPL.  Distributing the partially open source driver
     ("") may or may not be technically legal, since the
     GPL'ed code, though not yet linked with the closed-source code, is
     certainly intended to be so.  See this Kernel Traffic issue
     and a Linux-Kernel mailing list archive for the week including Dec.
     3rd, 2000, for more details.

  5.2.2.  Driver v5.78(c,d,e,...) - Installation

  You should obtain the most recent package for your kernel from
  <> and follow the up-to-date
  instructions given there.

  5.2.3.  Manufacturer's driver version 5.68 - Installation

  This driver is superseded by version 5.78, described above; however,
  it may still be of some use in special cases.

  1. Obtain the package for your kernel:

     a. 2.2.12 to 2.2.15  <>

     b. 2.2.15 and above : same URL, but "tty.h" patch is required; see
        "Tips and Tricks...", above.

  2. unzip

  3. su (enter root password when prompted)

  4. ./ltinst (a 'file not found' error will be issued due to a flaw in
     the installation script; ignore this error.)

     Your modem should now be accessible as the device /dev/modem or

  5.2.4.  Open Source Tools - Installation

  See the documentation with the source for instructions.

  5.3.  ESS

  5.3.1.  Overview

  Binary-only drivers for ES56T-PI (PCI) and ES56V-I (ISA), compiled
  under RedHat 6.0's kernel 2.2.12-20, are available.  The driver has
  been used via forced insertion up through kernel 2.2.15, and up
  through 2.2.17 using the "tty.h" patch described in the "Tips and
  Tricks..." section, above.

  5.3.2.  Installation

  1. Obtain the package for your modem:

  �  ISA:  <
     i/linux/kernel61/> or

  �  PCI:  <

  2. For kernel 2.2.15 and later, apply tty.h patch (See "Tips And
     Tricks...," above); recompile kernel and modules.

  3. Unpack the package with: unzip package_name

  4. Change to the root user: su (enter root password when prompted)

  5. Create the device file: mknod /dev/esscom c 127 1

  6. Make convenience device: ln -s /dev/esscom /dev/modem

  7. Make convenience device: ln -s /dev/esscom /dev/ttyS15

  8. Set device ownership: chgrp uucp /dev/esscom

  9. Set device permissions: chmod 666 /dev/esscom

     Masquerade module version (See "Tips And Tricks...," above):
     ./fixscript essmodem.o essmodem.fix.o

     Install module file: cp essmodem.fix.o /lib/modules/`uname

     Insert module in kernel: insmod -f essmodem

     (Optional) Provide for automatic module loading: add a line "alias
     char-major-127 essmodem" to the file /etc/modules.conf or

  5.4.  PCTel

  5.4.1.  Overview

  Binary drivers can be found at

  A Debian-style installation package for kernel 2.2.16 was made
  available by Corel at
  i386/utils/pctel-kernel-2.2.16-driver-cdl-v1.0_1.0.deb>, though this
  link appears to now be incorrect.  A gzipped/tarred package derived
  from the .deb is available here
  <>.  In addition, a driver for
  kernel 2.4 was contributed by Thomas Wright, and is also available
  here <>.  Other packages,
  requiring the superficial compilation described below, are also known
  to exist.

  5.4.2.  Installation

  There are apparently two types of PCTel module package around.

  1. A package (rpm or deb) which installs two module files, pctel_hsp.o
     and pctel_pci.o, in /lib/modules/2.2.16.

     With such a package, if you are running a kernel more recent than
     2.2.16, you will need to use forced insertion (insmod -f), and if
     you are not successful, might try the "fixscript" method used with
     the Lucent 5.68 and ESS modules above - but, note that this has
     not, to my knowledge, been tried out yet.  If you are running a
     kernel older than 2.2.16, you should consider upgrading your
     kernel, or else try the fixscripting as well (this is also not
     guaranteed to work).  Please send me a report if you get these to

  2. A package which, when unpacked, gives a set of libraries (hsp.a,
     etc...)  and a small C source file (ptmodule.c), which should be in
     directories like lib/ and src/module/.  If there are no
     directories, create them and arrange the files with:

     mkdir lib
     mkdir src
     mkdir src/module
     mv *.a lib/
     mv Makefile *.c src/module

  Now go to the directory src/module and type make.  This should
  generate the module file pctel.o, which will appear back up in the
  directory lib.  (The driver module is not the object file ptmodule.o
  in src/module!)

  The apparent version of the module generated in this way will match
  your current kernel version.

  With the modules in hand, proceed to install as follows:

  1. Change to the root user: su (enter root password when prompted)

  2. Create the device file: mknod /dev/pctel c 62 79

  3. Make convenience device: ln -s /dev/pctel /dev/modem

  4. Make convenience device: ln -s /dev/pctel /dev/ttyS15

  5. Set device ownership: chgrp uucp /dev/pctel

  6. Set device permissions: chmod 666 /dev/pctel

  7. Install module file (only for package type 2, above):  cp pctel.o
     /lib/modules/`uname -r`/misc/

  8. Insert module(s) in kernel with insmod -f modulename

  5.5.  Conexant/Rockwell HSF

  There exist drivers for kernels 2.2.14, 2.2.16, and 2.2.17 at
  <> The page is in French, but the
  installation commands are given on the page in boldface red text (you
  can also use the babel fish
  Essentially, download the appropriate package, unpack it with tar
  -zxvf, and run the installation script ins_all.

  This driver is a bit finicky (with the most common symptom of failure
  being the "NO DIALTONE" response), but a number of people have been
  able to get it to work, usually by inserting their modem's vendor ID
  in the modem's .inf file, perhaps along with a change of the device
  major number from 254 to 253.  See the mailing list
  archives for details; one example of many is given here

  5.6.  Intel (formerly Ambient Technology, formerly Cirrus Logic)

  Mikhail Moreyra has written a GPL'ed driver for the CL-MD5620DT
  chipset which can do up to 33.6 kbps; however, this is alpha software
  and should be treated with due care.  The driver can be obtained at
  <>.  Gabriel Gambetta
  (ggambett(at) issued a patched version of the driver
  to allow standard AT modem commands; you can get this version at Rob
  Clark's site here

  A driver for the HaM modem was beta-tested in early 2001 and is
  expected to be released quite soon.

  5.7.  3Com

  5.7.1.  56k

  An rpm package with a driver for the 3Com MDP3900V-U modem (apparently
  found in the Dell Dimension L733r) was posted to the
  mailing list (click here <
  cgi?1:mss:2942:200102:lminaknocblpmkfcnobi> for more information), and
  is mirrored here <>.

  5.7.2.  Mini-PCI

  A request for comments was posted by a 3Com official about the
  possible demand for a binary-only driver for their miniPCI combination
  NIC/winmodem here <
  cgi?1:msp:1229:cilpipdmolabpbbbibgd> on the mailing list;
  please respond to the address given,, and not
  to the mailing list.  Though to my knowledge no driver has yet been
  released, Werner Heuser's miniPCI page
  <> has more information and

  5.8.  AMR

  Ian Stewart reports <
  cgi?1:mss:2768:200102:edbonibpdjfpnfhbmhel> that he is working on a
  "mid-level driver" for the AC97 codec.

  6.  Troubleshooting

  So you've read through this document, the Modem-HOWTO
  <>, and the PPP Howto
  <>, are pretty sure
  that your modem matches one of the drivers available, but it still
  doesn't work?  There are a number of points in the process at which
  something could break down.

  Linux generally maintains records of networking connections which are
  very useful in troubleshooting problems.  Their particular filenames
  vary with both the Linux distribution and Dial-in software, but the
  system log files /var/log/messages, /var/log/syslog, etcetera, should
  provide at least some information.

  For both your own trouble shooting and queries for help to a list, it
  will be useful if you accumulate the information requested below. As
  root, change to the directory in which the modem install scripts are
  located, and start a script record as shown below.  After this script
  is terminated with "exit," copy it out of your Linux partition for
  transmission to the list which may aid you.

  (Below, # are explanatory comments.)

  # start the recording,
  script ModemTest.txt
  # type in as much info on your Modem card as you have
  echo winmodem name, manufacturer, designation, and chip if possible
  # this gives your current kernel version
  uname -r
  # this gives information on your serial ports
  setserial -agv /dev/ttyS*
  # this information on your interrupts (irq)
  cat /proc/interrupts
  # show the contents of your module installation script (insert script name):
  cat ScriptName
  # Check if your script is executable:
  ls -l ScriptName
  # a response is OK if it has "x" such as below:
  # -rwxrw-rw-  1 root     root  654 Jan  6  2000 ltinst
  # otherwise make it executable with:
  chmod o+x ScriptName
  # verify with
  ls -l ScriptName
  # if ScriptName has not been successfully run before under this kernel
  # run it with:
  # what is the symbolic link /dev/modem set to:
  ls -l /dev/modem
  # What is the DeviceName specified in the ScriptName (/dev/ttyS14 or ...?)
  echo DeviceName
  # what is your modem driver name? Something like DriverName.o
  # with the ".o" indicating it is a compiled binary
  echo This is my DriverName.o
  # if should have been inserted in the Modules Path
  # Try to display it there with:
  find /lib/modules | grep DriverName
  # Is DriverName among the modules installed in the running kernel?
  # if not try a simple insertion:
  insmod ./DriverName.o
  # or if it was in the Modules Path, the following will suffice:
  insmod DriverName
  # check for insertion:
  # if not inserted, try forcing:
  insmod -f ./DriverName
  # list your inserted modules again.
  # If DriverName is NOT listed,
  # their is an incompatibility between modem hardware, driver and kernel.
  # Further effort will be of No use.
  # If DriverName is listed, let's do a bit more information.
  # You may first wish to rerun the configuration utility
  # used to setup dial-in connections for your Linux installation.
  # Remember to edit your PassWord from this record later.
  # You will probably be queried for the following information
  # which you should have ready:
  #Port to be used (/dev/modem or /dev/ttySn),Dial-inNumber, UserName, PassWord.
  # Run your configuration utility.
  # To stop recording

  If dialin was not successfull, append to this a record from your log
  file.  As an example, a section of a /var/log/syslog from a Debian
  Linux system is below.

  7.  FAQ

  7.1.  I have a winmodem.  Will it work under Linux?

  Probably not.  Please see the section "Which Linmodem hardware is
  supported?" above, and check the Linux Modem Compatibility database
  <> at Rob Clark's
  site <>.

  7.2.  I get "NO DIALTONE".

  Try setting your BIOS option from "PNP OS" to "non-PNP OS",  from
  "Windows" to "Other OS", or the equivalent.

  Conexant users: See the Conexant section, above.

  7.3.  I get a "device or resource busy" error.

  �  If you have an ISA modem, did you use the isapnptools to allocate
     IRQ and DMA resources to the card?  See "ISA Plug-n-Play", above,
     for more information.

  �  Double-check that you created the device file correctly, and try to
     eliminate any IRQ conflicts you might have.  If all looks well, but
     it still doesn't work, check the
     <> mailing list to see if someone else has (and
     has perhaps fixed) the same problem, or try to fix it yourself and
     inform others of your results.

  7.4.  I get unresolved symbols when fixscripting/insmoding.

  Unresolved symbols are a true danger of version mismatching and are,
  in general, bad, but are also almost inevitable with binary modules.
  If the fixscript reports unresolved symbols, or the module does not
  work despite the unresolved symbols, you may be out of luck with that
  kernel/module combination; however, a few common cases involve symbols

  �  slhc_xxxx:  You probably need to insmod the slhc module before
     inserting the modem/ppp modules; using modprobe rather than insmod
     should also obviate this problem.

  �  printk, jiffies:  Your kernel may be compiled with SMP enabled.
     None of the binary modules are known to be SMP-safe, and will
     probably only work on a single-processor machine with a single-
     processor kernel, i.e. SMP disabled.  You should try recompiling
     your kernel or otherwise obtaining a version with SMP disabled.
     (Thanks to Tom Reinertson (treinertson(at)

  �  tty_xxxx with esscom.o: Earlier fixscripts were not able to handle
     the version-specific symbols in this module.  More recent versions
     are available at
     <>) which should be
     able to fix this module as well.

     If a module works in an unstable fashion, it could be that, under
     some circumstances, you are avoiding those symbols, while in
     others, you slam up against them.  Try out different ppp dialup
     programs (wvdial, kppp), which call a different set of functions
     under similar conditions.  It is also possible that the fixscript,
     which was designed for the lucent module, is not "fixing" the
     symbols used in your module.  If you find no combination that
     works, consider "downgrading" to a kernel which has a closer
     version match to that of the module.

  7.5.  My PCTel modem doesn't work.

  �  Do you need to give the module a country code parameter?  See the

  �  Are you using the right driver module?  There are a few PCTel
     drivers around (see the section "Which Linmodem hardware is
     supported?" above).  You might try one of the others and see if
     that helps.

  7.6.  The modem dials and connects fine, but then it drops the connec�

  This is an often-reported problem that may have a few, or no,

  1. It is possible that the module is installed correctly and is
     working, but that you have a problem with your ppp configuration.
     In particular, if you find an error in the log along the lines of
     "peer is not authorized," try changing "auth" to "noauth" in
     /etc/ppp/options, and/or commenting out "auth" and "lock" (by
     placing a '#' at the beginning of the line).  Corel has a FAQ entry
     at <> about this.

  2. It has been reported that, with some kernel/module mismatches, a
     program like kppp will give this error, while an alternative like
     wvdial does not, for the same modules and hardware.  You may wish
     to try a different ppp dialer and see if that helps.

  3. Lastly, there is the potential relationship with sound support.
     Comparing functionality of ltmodem.o with/without sound support in
     the kernels, dial-in is OK, but ppp is NOT achieved for the kernel
     without sound support.

     Most Linux distributions do deposit a kernel configuration file
     along with the kernel.  For Debian related distributions, it is the


  The positive choices can be quickly displayed with:

    grep SOUND /boot/config-version |grep -v not

  For the specific example of a 2.2.17 version:

  # grep SOUND  /boot/config-2.2.17 |grep -v not

  Either CONFIG_SOUND=m or CONFIG_SOUND=yes would show that the kernel
  has sound support (as would simple sound output).

  If none of these helps, you may wish to consider trying to use a
  kernel version which is closer to the module.  Otherwise, try the
  mailing list at <> for help.

  7.7.  I get a kernel panic on closing the connection or unloading the

  There are a couple of possible solutions to this, neither of which may

  �  Try a different ppp dialer (wvdial, kppp).

  �  Configure the module so that it stays in the kernel, i.e. so that
     it is not unloaded.

  7.8.  Nothing seems to work.  To whom can I turn for help?

  �  Double-check that the modem you have is actually supported by the
     module you have.  See "Which Linmodem Hardware Is Supported?"

  �  Try to determine at which stage of the installation process things
     break down.  Check the man pages on the commands used in that stage
     and see if you can determine the source of the problem.

  If all seems lost, please see the section "Troubleshooting", below ,
  and consider sending a message with the complete information described
  there to the mailing list at <>.

  7.9.  Who wrote the driver for my winmodem, and how do I contact

  If a contact address is not given above, you can in general assume
  that it was probably somebody on contract to the manufacturer, who
  probably does not have the authority the update/release/change the
  source code, and who probably doesn't have time to reply to your email
  in any case.  See, for example,

  8.  Appendix

  8.1.  PCTel Module Parameters:  Country Code

  The following is quoted from one of the PCTel readme files.  Thus you
  can choose the appropriate country code by inserting the module with a
  parameter as:

  insmod pctel.o country_code=7

  (the "7" being replaced by your country code from the list below).
  Thanks to Jonathan Emery for pointing out the correct syntax.

  Set and report country code.

  This driver takes a module parameter to setup the correct country code
  setting for various country's telephone networks and it also can report
  back the country code been set.

  Here are the two versions for country_code selection and reporting:


  To set country code:
  "country_sel_rep   sel   7" will sets the country code to 7.

  To query the driver for the currently set country code:
  "country_sel_rep   rep" returns the current country code as the exit code.


  To set country code:
  "country_sel   7" to set the country code to 7.

  To query the driver for the currently set country code:
  "country_rep" return the current country code as the exit code.

  country_code                    country_name

      1                           USA
      2                           FRANCE
      3                           GERMANY
      4                           ITALY
      5                           SWEDEN
      6                           UK
      7                           JAPAN
      8                           AUSTRALIA
      9                           SPAIN
     10                           TAIWAN
     11                           SINGAPORE
     12                           KOREA
     13                           SWITZERLAND
     14                           NORWAY
     15                           NETHERLANDS
     16                           BELGIUM
     17                           CANADA
     18                           IRELAND
     19                           PORTUGAL
     20                           POLAND
     21                           HUNGARY
     22                           FINLAND
     23                           DENMARK
     24                           AUSTRIA
     25                           S.AFRICA
     26                           CTR21 COUNTRIES
     27                           CHINA
     28                           MALAYSIA
     29                           LUXUMBURG
     30                           GREECE
     31                           ICELAND
     32                           NEW ZEALAND
     33                           BRAZIL

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