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Receiving normal SMS messages works fine. I see a "+CMTI: "ME", <idx>" notification on the Virtual COM port. I can then read the message with AT+CMGR and find it in the AT+CMGL list.

However when receiving a WAP push message (that is an MMS notification), nothing is printed on the Virtual COM port, and nothing is to be found when executing AT+CMGL=4. If I hook up USBPcap+Wireshark while receiving the WAP push, I can see that on some other interface (the interface used for internet?) I see some binary data that includes the full WAP push SMS message, so it is apparently received by the module.

Before I firmware upgraded to Quectel version BG96_Firmware_Release_Notes_V0207_01.016.01.016, I could see some bogus "+CMTI: "ME", -1" notifications when the WAP push arrived, but now after the firmware upgrade nothing is shown anymore. According to the release notes it fixes a bug with description "Fixed the bug that unexpected URC “+CMTI: -1” reported when module received WAP push type message.".

Putting in the same SIM card in an old D-Link DWM-157 modem and then hooking up the Virtual COM ports, I can now clearly see the WAP push messages coming in with +CMTI, as well as the message can now be found with AT+CMGL and read with AT+CMGR.

So for some reason TRM250 seems to discard incoming WAP push messages. Is this a bug?

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This issue is more related to the Quectel Forum. TRM devices do not have RutOS, and communication takes place directly with the module, the device itself does not have to discard anything.

TRM devices uses Quectel BG96 modules. Double check that you are using the correct AT commands. You can find the full list here: https://www.quectel.com/UploadImage/Downlad/Quectel_BG96_AT_Commands_Manual_V2.3.pdf

Note the message format: this is PDU or TEXT mode. If AT+CMGF=1 (Text mode) is used, the list messages command will be AT+CMGL="ALL" (but not AT+CMGL=4). And to read a message type AT+CMGR=<msg.index>


Thanks for the answer. I use PDU mode (not text mode) and the correct AT commands according to that document.

It would be interesting though to see if other people get the same issue, by sending an MMS to the phone number represented by the SIM card inside the module.

I'll try to post the issue on the Quectel Forum.

Here is what I see when I send a MMS message to the TRM250:


Interesting... Do you get unsolicited messages too when the MMS push notification arrive, on the DM Port?

This is the firmware I have: https://forums.quectel.com/t/bg96-firmware-upgrade/3526.


sorry I missed your comment. Were you able to get help from the Quectel forum?
What difficulties are you facing now?