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EC25-AU: not receiving URC for LTE data

I am testing the EC25-AU on an ARM-A7-based platform running Linux 4.19.35. Response to AT+GMR command is EC25AUFAR02A04M4G. I am using the qmi_wwan driver with USB interface.

I am trying to get the modem to work while the SoC is in suspend-to-RAM state by waking the processor up using the RI pin when it has data to report. The RI pin is connected to a GPIO on the SoC. I can successfully suspend the SoC, send an SMS to the modem, and verify that the RI pin is pulsed low, waking the SoC from its suspend state. However, I want to be able to wake the SoC when it receives IP data. To test I send a series of UDP packets from a remote location to the modem’s address. When the SoC is in a normal state (i.e. not suspended), the packets are received without problem. However, there is no indication from the modem in way of RI pin pulse or URC that data has been received.

Is there any way to configure the device so that this happens? The ability to wakeup from IP traffic is very important to my application.

Dear Hjm,
Thanks for your inquiry in Quectel forum.
About your issue, could you help to double check whether you have read out the data that you the module have received last time if therr have no URC report when you received the data from your server ? You also can use AT+QIRD to read the data to check it. Thanks!

Hi Kyson - I am reading the incoming packets from a socket and can confirm they are being received but no URC is being reported.

I would prefer to use qmi_wwan rather than AT commands to communicate with the modem if possible

Also I should mention that I am monitoring the USB serial interface for URC. I receive +CMTI: "ME" messages when I send an SMS to the device (along with RI pin pulse) but still nothing for UDP.

If that, you can try to use the following command to confirm whether the URC report setting is just USB serial interface. And you also cna double check whetehr you have read out all the data received from server when you send data again. Thanks!


I get +QURCCFG: "urcport","usbat" in response to AT+QURCCFG="urcport" command. I am monitoring both ttyUSB3 and ttyUSB2 and getting no URC. Same result if I use AT+QURCCFG="urcport","usbmodem". But what do those commands have to do with the behaviour of the RI signal? I have AT+QCFG="risignaltype" set to "physical".

Yes all the data has been read

Have you check whetehr the module have received the data and just without URC or the module have not receive the data ?
By the way, please double check the following command to comfirm whether there have any error setting. If it is normal, the only possible reason is that the module may have not receive the data. If the module cannot receive the data, it is normal that have no URC report. If the module can receive the data normally, and you confirm have read out all the received data, but it still have no URC, it may need to catch debug log to confirm the reason. Thanks! About how to catch debug log, please send email to, then our local FAE will support you. Thanks!


Yes, the data is received (i.e. I can read it from a UDP socket) however there is no URC (no RI signal or message via USB serial).

All of the URCs below are set to 1 except for ccinfo which returns ERROR when I try to query it. Although ccinfo is for indicating voice call state change so perhaps it isn’t relevant here?

Will do, thanks

What was the proposed solution ?