I need help with an issue regarding STM32L462RE (BL462ECELL1). How do you connect the modem to a network? I have been trying to use X-CUBE-CELLULAR. I flashed the binaries and know I can get some info from the modem, however i can't connect to the network

[SPere.2]

It keeps sending itself at commands and not connecting to the network.

[S.RA]

Dear FLeel.1

Can you clarify if you are using the embedded SIM car inside the Module or a plastic SIM card? If you are using the embedded SIM card then did you activate the SIM trough Truphone Portal?

If you have activated the SIM card successfully then we should ensure that the place you are locate is covered by Truphone Network. Can you tell me in which country the device is trying to connect?

Based on the log I see that Modem does not find network. Please can you let the Modem scan the full bands on Cat M? Can you share more trace to understand more the issue?

Thanks a lot

Best Regards

Solofo

[SPere.2]

Dear Solofo

I am not using the embedded SIM card, I am using a plastic SIM card from a local operator, trying to connect from Portugal. However this card only supports NB-IoT and you refer CAT-M. Does the Modem support NB-IoT? I read it supports LTE Cat.M1/Cat NB1, but I want to be sure it supports NB-IoT.

Some more of the trace is in the attached file.

Thank you for your time.

Best regards,

Sara

[S.RA · Accepted solution]

Dear Sara,

Thanks for the log. In the trace I do see that the internal SIM card is still used since the SW did not detect any SIM card on the SIM slot. Did you insert the SIM card properly on the SIM slot?

Yes the modem support NB-IoT. To enable it, you need to send an AT command at at%setacfg=radiom.config.preferred_rat_list,"NBIOT".

You enter this command on the terminal at anytime.

If you do not want to be disturbed by the trace, then i suggest you to configure the X-CUBE-CELLULAR to only run the modem as following:

1/ enter on the terminal "cst target off" to power of the Modem

2/enter "cst target modem" to Power on the Modem only. X-CUBE-CELLULAR boots the Modem and now ready to send any AT command to the Modem.

3/enter "at at%getacfg=radiom.config.preferred_rat_list" to read the current RAT. It should return CatM

4/enter "at at%setacfg=radiom.config.preferred_rat_list,"NBIOT" to select NBIoT. This configuration will be stored in the modem flash memory.

Now you can reboot the device, the Modem will search only NBIoT

I hope it helps

Best Regards

Solofo

[SPere.2]

Dear Solofo,

Thank you very much for your help! I ony had the oportunity to answer you know. It worked.

Best Regards

Sara

[S.RA]

Dear Sara,

I'm glad to know that it works.

Thanks a lot for

Best Regards

Solofo

[SPere.2]

Dear Solofo,

If instead of configuring for NBIOT, I wanted to configure for LTE-M (cat M1), how would you write the command?

Thank you :)

Best Regards

Sara

[McLovin]

"at at%setacfg=radiom.config.preferred_rat_list,"CATM"

[SPere.2]

Thank you! :)

[ARodr.17]

Hi @McLovin​, I am trying to understand how to configure and use the modem with writing my own firmware, I understand that you have to send the "at" commands through the uart, but how do you know which commands to send? and how if you are doing a new project? I have the tcp_echo_client example, but I dont really understand how this works. Can you help me? Thanks