PPP and the backslash-containing AT command in ppp.conf

[Michael Vondung]

I am fairly to FreeBSD (and any kind of Unix), so please be easy on me in
case I'm overlooking the obvious. :)

I've been trying to connect to my ISP with an external "Elsa Microlink
ISDN/TL pro" modem. The init string that the modem requires is AT&F\N9. I
modified the following line in /etc/ppp/ppp.conf:

 set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 5 \
  \"\" AT OK-AT-OK AT&F\\N9 OK ATE1Q0 OK \\dATDT\\T TIMEOUT 40 CONNECT

The man page for chat
(http://www.freebsd.org/cgi/man.cgi?query=chat&sektion=8) says that \\ sends
a backlash character, so I figured that AT&F\\N9 would be sent as AT&F\N9.
However, it doesn't seem to send a backslash. Here's the relevant bit from
/var/log/ppp.log:

Sep  1 15:01:36 catbox ppp[372]: tun1: Chat: deflink: Dial attempt 1 of 1 
Sep  1 15:01:36 catbox ppp[372]: tun1: Chat: Send: AT^M 
Sep  1 15:01:36 catbox ppp[372]: tun1: Chat: Expect(5): OK 
Sep  1 15:01:37 catbox ppp[372]: tun1: Chat: Received: AT^M^M 
Sep  1 15:01:37 catbox ppp[372]: tun1: Chat: Received: OK^M 
Sep  1 15:01:37 catbox ppp[372]: tun1: Chat: Send: AT&FN9^M 
Sep  1 15:01:37 catbox ppp[372]: tun1: Chat: Expect(5): OK 
Sep  1 15:01:37 catbox ppp[372]: tun1: Chat: Received: AT&FN9^M^M 
Sep  1 15:01:37 catbox ppp[372]: tun1: Chat: Received: ERROR^M 
Sep  1 15:01:42 catbox ppp[372]: tun1: Chat: Expect timeout 
Sep  1 15:01:42 catbox ppp[372]: tun1: Warning: Chat script failed 

I have also tried this with AT&F\N9, AT&F\\\N9 and AT&F^\N9. I'm unsure why
the script expects "timeout" and not "CONNECT". If I leave out "AT&F\\N9 OK"
before ATE1Q0, the modem will dial (the LNE LED indicates that an ISDN
connection is being established), but won't get a carrier. In this case the
log looks like this:

Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: deflink: Dial attempt 1 of 1 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Send: AT^M 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Expect(5): OK 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Received: AT^M^M 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Received: OK^M 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Send: AT&F^M 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Expect(5): OK 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Received: AT&F^M^M 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Received: OK^M 
Sep  1 14:58:43 catbox ppp[359]: tun1: Chat: Send: ATDT019102345^M 
Sep  1 14:58:45 catbox ppp[359]: tun1: Chat: Expect(40): CONNECT 
Sep  1 14:58:45 catbox ppp[359]: tun1: Chat: Received: ATDT019102345^M^M 
Sep  1 14:58:45 catbox ppp[359]: tun1: Chat: Received: NO CARRIER^M 
Sep  1 14:58:45 catbox ppp[359]: tun1: Warning: Chat script failed 

Any help is greatly appreciated.

Thanks!