Cellular Modem, PPP, and FreeBSD

[Jordon Hofer]

Greetings.  I am running a stripped down version of FreeBSD 4.11 on an
embedded x86 board.  I have an embedded cellular modem module (from
MultiTech) that is attached to the serial port (going through the necessary
RS232-TTL chip).  I am using PPP to connect to the Internet through verizon.
Everything works well until the connection gets interrupted.  I am using
ddial mode, so if the connection drops, it will redial.  From the logs, I
can see that PPP tries to redial, but after the initial connection, the
modem does not respond to any at commands.  If I power-cycle the modem, it
will connect just fine the next time PPP tries to reconnect.

I realize that there is a good chance that the problem is in the modem.  I
am just wondering if there are any cases where you need a special chat
script to handle disconnects to return the modem to a clean state.

Also, if there is a better group for this, please let me know.

Thanks.


Jordon Hofer
Dir. Software Engineering
AgSense LLC