Conduit mLinux: signal strength of 3g Modem

[Patrick B.]

I’d like to monitor the signal strength of my established 3G connection.

I configured pppd to keep the connection alive if it closed by the other side (with the ‘persist’ option) and therefore I also set the option ‘lock’ (maybe unnecessary).

This makes that PPPD is keeping the /dev/modem_at0 open and locked.

With the AT command AT+CSQ I could fetch the information I need. at0 is locked and I tried the following on /dev/modem_at1:

root@mtcdt:~# microcom /dev/modem_at1 
AT+CSQ
+CSQ: 11,2

OK

Is at1 a second serial connection to the modem meant for exactly that?

• This topic was modified 7 years, 2 months ago by Patrick B..

[Jeff Hatch]

Patrick,

You are correct that /dev/modem_at1 is a second tty with access to the modem for AT commands. The intent is for that tty to be used for other entities than pppd to do exactly the type of things you are trying to do with it, monitoring being the main thing.

Jeff

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