Receive SMS in transparent mode



We are using a Supreme 10 with TPC/IP.

The question is that holding a GPRS conection in transparent mode we need to check if a new SMS is coming. Now, we are sending +++ and switching to command mode, reading the mailbox and return to transparent mode. But this is not good for us because needs to repeat the operation frecuently to check every 10 seconds.

Does somebody know a better way to do this???



check the cmux drivers.
they allow for (up to) 4 virtual serial ports to the wavecom module



But isn’t this a Radio/Network issue? I don’t believe that the Q2686 can do simultaneous DATA and VOICE (i.e. SMS) bearers.

However, I do know that the Q2686 will park a GPRS session when an inbound VOICE session is established, and re-establish the GPRS session once the VOICE session has ended.

Maybe the SMS behaves the same way? I would look at writing an OpenAT app that registers for SMS events and handles the GPRS traffic. Then the app could use the CMUX interface to pass DATA down one virtual serial port, and provide SMS events down another…

Just my 2c worth…

ciao, Dave


Yes, the Q26 (and Q24) can receive an inbound SMS while a GPRS session is in progress.



That’s good to know.
Maybe the quick and dirty solution is to buy one of the IESM boards with USB, and use the USB console to monitor SMS events.

No code required?

ciao, Dave


also, sms is not necessarily a voice service. (my simcard doesn’t have voice service but can send and receive sms)
and in my phone i can choose which bearer to use when sending / receiving sms.


Or an IESM board with the 2nd UART…


Wavecom also has that option



Thanks for that - I had it in my mind that it was a Voice service as it’s so tightly coupled in the ISP billing options…

ciao, Dave


AIUI, SMS is normally carried in a GSM signalling channel.

I’ve seen the option in the Wavecom docs to carry SMS over GPRS, but never looked into it.

Would SMS over GPRS be cheaper…?


I don’t know about other countries, but here in Denmark, our operators clearly state that they bill you with the same amount no matter if you send the SMS over GPRS or GSM.


Thank for your anwers.

I understand that CMAX is the way. But, is neccesary specific software for virtual port in the PC? In afirmative case, does it exist for Windows CE?



The “CMUX” driver for PC is available in the Download section of the Wavecom web site (Drivers, CMUX Driver).

Under Win CE, there is a Radio Interface Layer (RIL) which offers an easy access (using APIs) to all the features of the GSM/GPRS/3G modem (or module).

The RIL also uses MUX in order to be able to run AT command on a channel while a data transfer is running on another channel.
(e.g. this allows Win CE to receive an SMS while browsing the web).

Wavecom provides RIL/MUX drivers for:

  • Windows CE 6.0
  • Windows Mobile 6.x
  • Windows Mobile 5.x

Click [here] to obtain RIL/MUX drivers for Embedded Windows® (link also available in the Download section, Drivers, RIL Driver).



Thank you very much.

I´m going to try it inmediatly.



Sorry, my OS is CE 5.0. Can I do something??