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>12.26. Built-In Modem</H1
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CLASS="sect2"
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CLASS="sect2"
><A
NAME="AEN3192"
></A
>12.26.1. Modem Types</H2
><P
>&#13; There are three kinds of modems available: internal,
<SPAN
CLASS="acronym"
>PCMCIA</SPAN
> card or external serial port modems. But
some internal modems will not work with Linux these modems are usually
called WinModem. This is caused by non-standard hardware. So you have to use either a
<SPAN
CLASS="acronym"
>PCMCIA</SPAN
> card modem or an external modem (serial or USB). The
<A
HREF="http://walbran.org/sean/linux/linmodem-howto.html"
TARGET="_top"
>LinModem-HOWTO</A
>
by Sean Walbran provides a detailed instruction how to deal
with these kind of modems. My pages about
<A
HREF="http://tuxmobil.org/modem_linux.html"
TARGET="_top"
>Internal Modems in Laptops</A
>
and
<A
HREF="http://tuxmobil.org/minipci_linux.html"
TARGET="_top"
>miniPCI Devices in Laptops</A
>
provide a survey about the modem controllers used in different laptops.
</P
><P
>&#13; Quotation from the Kernel-FAQ: "9.Why aren't WinModems supported? (REG,
quoting Edward S. Marshall) The problem is the lack of specifications
for this hardware. Most companies producing so-called
<EM
>WinModems</EM
> refuse to provide specifications which
would allow non-Microsoft operating systems to use them. The basic
issue is that they don't work like a traditional modem; they don't
have a DSP, and make the CPU do all the work. Hence, you can't talk
to them like a traditional modem, and you -need- to run the modem
driver as a realtime task, or you'll have serious data loss issues
under any kind of load. They're simply a poor design."
</P
><P
>&#13; "<EM
>Win</EM
> modems are lobotomized modems which expect
Windows to do some of their thinking for them. If you do not have
Windows, you do not have a connection. "
</P
><P
>&#13; Anyway, I have set up a page collecting information on laptops with internal modems at
<A
HREF="http://tuxmobil.org/hardware.html"
TARGET="_top"
>TuxMobil - Hardware</A
>
. Maybe it's possible to run such modems with MS-Windows9x/NT
emulators like <B
CLASS="command"
>wine</B
> or <B
CLASS="command"
>VMware</B
>, but I don't know it.
</P
><P
>&#13; The
<A
HREF="http://linmodems.org"
TARGET="_top"
>Linux WinModem Support</A
>
and
<A
HREF="http://www.xmodem.org/"
TARGET="_top"
>the Xmodem.org (former Gromit Winmodem) page</A
>
are more or less the standard as to whether a modem is
real or not, and also contain directions to getting drivers for the few
winmodems that do have Linux drivers.
</P
><P
>&#13; There is a driver for Lucent WinModems available.
LucentPCI (binary only) driver, for PCI driven internal modems, see
<A
HREF="http://linmodems.org"
TARGET="_top"
>Linux WinModem Support</A
>
and the
<A
HREF="http://www.close.u-net.com/ltmodem.html"
TARGET="_top"
>LTModem diagnostic tool</A
>.
</P
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NAME="AEN3214"
></A
>12.26.2. Caveats</H2
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>&#13; Pay attention to the different kinds of phone lines: analog and ISDN.
You can't connect an analog modem to an ISDN port and vice versa. Though
there might be hybrid modems available. Connecting to the wrong port may
even destroy your modem. Trick: If you are looking for an analog phone
port in an office building which is usually wired with ISDN, take a look
at the fax lines, they are often analog lines.
</P
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>&#13; If your machine features an internal modem as well as an internal
ethernet card, pay also attention to plug the right cable into the plug.
Otherwise you may damage your hardware easily. It may even cause a fire.
</P
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><P
>&#13; For tracking the packets on PPP you may use <B
CLASS="command"
>pppstats</B
>.
Or <B
CLASS="command"
>pload</B
> this provides a graphical view of the traffic
(in and out) of the PPP connection. It is based on athena widgets hence
is very portable. It also uses very little CPU time.
</P
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