Using AT commands to control the LTE

RE: Using AT commands to control the LTE

Charlie — Mon, 31 Mar 2025 12:45:24 GMT

Hi Jelena and Kevin,

Please consider another potential cause:

Unusual blocking of LTE-M and NB-IoT by certain carriers | Onomondo Help Center.

You may record a modem trace and share it with us for analysis to better understand what happens at the low-layer communication protocols.

Best regards,
Charlie

RE: Using AT commands to control the LTE

Kevin Kotinkar — Mon, 31 Mar 2025 11:33:11 GMT

Hi,

it would be AT+CPIN? including the question mark to check on the SIM card status.
You also first need to turn on the modem (e.g. AT+CFUN=1 or solely for the UICC/SIM card inteface with AT+CFUN=41.)

Also, I recommend to enable both NB-IoT and LTE-M to increase possible coverage
(run this command before CFUN command).
AT%XSYSTEMODE=1,1,0,1

The DK SIM cards come with a limited amount of data (I believe it was 5-10 MB), hope this is not the issue.
You can register the Onomondo SIM card to get additional data.

You may also try to factory reset the modem using AT%XFACTORYRESET=0 and ensure that you run on the latest modem firmware (v2.0.2):

https://www.nordicsemi.com/Products/nRF9151/Download?lang=en#infotabs

Best,
Kevin

RE: Using AT commands to control the LTE

newnow — Mon, 31 Mar 2025 09:09:19 GMT

Dear Kevin,

Thank you for the quick answer. I am using an Onomondo sim card that came together with the nrf board. I also tried a Conexa sim card, and it was also unsuccessful.

On the Onomondo website, I can track the activity of the sim card, and when it was inserted in my phone, it was active, but when it is in the nrf board, no activity is recognized.

Regarding disabling NB-IoT, I was following commands from dev academy (academy.nordicsemi.com/.../) for manually connecting to the LTE network.

AT+CPIN command gives me "ERROR".

RE: Using AT commands to control the LTE

Kevin Kotinkar — Mon, 31 Mar 2025 09:00:27 GMT

Hi, which SIM cards do you use?

It wonders me that they work fine with your mobile phone, since those use a different technology (not LTE-M / NB-IoT).
You need specific LPWAN SIM cards.

You also specifically disabled NB-IoT, is there reason for that?

Check the SIM card status with: AT+CPIN?

Best,
Kevin