Can't Query External Serial Modem

Tommy Trussell tommy.trussell at
Tue Mar 13 02:56:58 UTC 2007

On 3/12/07, Bernard Helyer <b.helyer at> wrote:
> I should clarify - HyperTerminal doesn't cause the lights to respond,
> wvdialconf does. And minicom sends the lights flashing maybe 1 time in
> 30/40.

The send/receive lights should flash with every keystroke, so my first
thought is that either the cable is bad, wired wrong, or you're not
pointing at the right serial port. Many PCs have two, and the first
and second ports are usually at /dev/ttyS0 and /dev/ttyS1 (though that
can possibly vary depending on your specific hardware, etc.). Notice
the capitalization, and that the final character is a number.

Try both ports (if you have two physical ones). Also look at the cable
to see if it looks kinked or if any of the pins are bent.

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