[lug] external modem configuration

David Lovering lovering at boulder.nist.gov
Mon Nov 15 08:30:19 MST 1999

Dear Kelly:

    Regarding your note -

-----Original Message-----
From: KELLEY SCOTT T <kelleys at ucsu.Colorado.EDU>
To: lug at lug.boulder.co.us <lug at lug.boulder.co.us>
Date: Wednesday, November 10, 1999 11:38 AM
Subject: [lug] external modem configuration

>I was wondering if anyone could help me to set up my external modem. The
>modem is plugged into a serial port and using windows I
>find it under COM2. I've tried linking to the tty devices for COM1 and COM
>2 but the kppp utility still can't find the modem. Does anyone know what
>the problem might be? Is there a quick way to use linux to find out what
>device I should link to (i.e. find where the modem is)?
>Thanks for any help you can give me. -Scott

    Have you tried /dev/ttyS0 and/or /dev/ttyS1?  Remember -- the current
invocations of
    linux are moving away from the /dev/modem and /dev/cua0-style port

    Also, some DUART implementations don't support "floating" ports with
just the TD/RD/GND
    pins -- the character buffer isn't enabled unless DSR, CTS, and/or DCD
are active.  This
    can be "rigged" with a custom cable which hot-wires these pins to DTR,
but it's better to
    do things properly and make sure both your serial port and that of the
remote device are
    asserting the proper signals up-front.

    -- Dave Lovering

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