Sample lwm2m_client can not connect to the network

[Gergely01]

Hi,

I want to get running the sample "lwm2m_client" on the board nRF9160DK (PCA10090).

Modem FW Version: 1.2.0.

I build the sample with Segger Embedded Studio v4.52

I also use the nRF Connest v3.4.1 (LTE Link Monitor)

After I have built the solution, I uploadad the intel HEX file named "merged.hex"

But the device can not connect to the network (even if I am waiting for a long time - 30 min):

After this, I checked the system mode with AT commands (AT%XSYSTEMMODE?). Respons: AT%XSYSTEMMODE=1,0,0,0

It means: LTE-M enabled, NB-IoT and GPS disabled. My SIM card can work just with NB-IoT (no LTE-M). My location is in Vienna, Austria, SIM Card: T-Mobile Austria, Deutsche Telekom Group.

With AT commands I set SYSTEM MODE to 0,1,1,0 (no LTE-M, but NB-IoT and GPS enabled). After AT+CFUN=0 and shut down the device it keeps this setting (I tested it).

After running the sample "lwm2m_client" again, the system mode settings were 1,0,0,0 again (LTE-M, but NO NB-IoT and GPS), and the device could not connect to the network.

I think the problem ist, that the sample "lwm2m_client" set the system mode to 1,0,0,0 (LTE-M only), but I can not find, how I can change it to NB-IoT (AT%XSYSTEMMODE=0,1,1,0) in this sample. 

Thanks for any help!

[Heidi]

Hi!

First, please try adding the configuration

CONFIG_LTE_NETWORK_MODE_NBIOT_GPS=y

to your project and running it again.

It looks like if nothing is specified, the LwM2M Client sample tries to connect with LTE-M first. 

If this doesn't fix the issue:

Could you please go to LTE Link Monitor and press this button after logging, and then save and attach the text file that pops up. That will help me see what's going on. Unfortunately the pictures you attached don't give me much information. 

Taking a modem trace while trying to connect would also help me see what's going on.

Best regards,

Heidi