Roaming with gsm modem

[Mark]

Hi,
I have a Wavecom M1306B gsm modem and am having difficulty with its
roaming settings. It is connected to a node however when the
connection is lost the modem will not attempt to reconnect to the
network. To get the modem to work again the SIM has to be removed and
inserted into a mobile phone to initialize it. I have looked at the AT
commands for the modem but have only found the

AT+CREG=<mode>

command. Is this relevant to what I wish to achieve?

This is a "second hand" project given to me to improve and I am
completely new to GSM modems, AT commands etc and any help would be
greatly appreciated.

Mark

[alysko]

The question is what is wrong. In my experience, the firmware versions 41 and 51 for Wavecome modems had a bug. The modems lost connection and never wanted to get it back. The initialisation did not help, just as in your case. I believe that it was a bug in the firmware because the modem responded to most of the commands correctly (it also used to tell me that there is a GSM and GPRS networks present and the modem is attached to them) but it did not give a complete response to the AT+CREG but only a partial one.

Well... it might still be a different case for your situation. For the set of commands, I would recommend you to contact the nearest dealer of Wavecom (here, in South Africa, it is Trinity Telecomms, www.trintel.co.za) and ask them for the manual matching your particular version of the firmware.

By the way, you can find a lot of manuals by typing:

"at+creg" "at+cgdcont" wavecom

 in Google.

Examples:

http://www.gprsmodems.co.uk/m1306b/P_AT_Commands_Interface_Guide_for_x51.pdf

http://www.stpro.ru/soft/GM29_technical_description.pdf#search=%22%22AT%2BCREG%22%20modem%20gsm%20gp...

(the second one uses mostly compatible GSM- and GPRS- sets but incompatible IP stack)

I have also found a thread here: http://www.telesys.ru/wwwboards/mobile/11/messages/3284.shtml. From that thread, I would advice you to check:

1) IMEI (that it is not default, like in http://www.telesys.ru/wwwboards/mobile/11/messages/3270.shtml)

and, possibly:

2) CGDCLASS (to set to CC)

3) CGDCONT parameters (up to your service provider)

By the way, if you are interested, there are GSM / GPRS libraries available (e.g. http://www.lysko.com/ -> Products).

Message Edited by alysko on 09-27-2006 03:01 PM