Re: Issue on connect 2 modems with a single phone line

From: Ondrej Zary
Date: Thu Dec 16 2004 - 06:26:10 EST

Pavel Machek wrote:
> Hi!
>> I want to try serial console in order to see the
>>complete Linux kernel oops.
>> I have 2 computers, one is a PC, and the other is a
>>Laptop. Unfortunately,my Laptop doesn't have a serial
>>port on it. But then, the each machine has a internal
>>serial modem respectively.
>> Then, can I use a telephone line to directly connect
>>the two machines via their internal modems (i.e. One
>>end of the telephone line is plugged into The PC's
>>modem, and the other end is plugged into The Laptop's
>>modem directly), and let them do the same function as
>>two serial ports and a null modem can do? If it is,
>>How to achieve that?
> You'd need phone exchange to do this. Most modems will not talk using
> simple cable. With 12V power supply and resistor phone exchange is
> quite easy to emulate, but...
> Pavel

I've tried it with 2 older Microcom modems and a piece of cable and it worked. Opened terminal on both sides, wrote ATDT123 (or any number you like) and ATA on the other. But if the laptop modem is a software modem, this will not work.

Ondrej Zary
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