NRF9160 DK cannot connect with NB-IoT network.

[Charlie5189]

I just get one NRF9160 DK(PCA10090 0.9.0) to test the default asset_tracker application with Basis Simcard in the Oslo area. The modem firmware is mfw_nrf9160_1.1.0.zip. I download the default application firmware from here. Firstly, I test the nrf9160dk_asset_tracker_2019-11-29_d3130d77.hex using LTE-M and it works fine, then I programed the nrf9160dk_asset_tracker_nbiot_2019-11-29_d3130d77.hex and completely do reconnection with nrf cloud with this step by step guide, but the LTE label on LTE link monitor keeps showing yellow blinking and take a very long time to become green.

I use AT%XSYSTEMMODE? to check the process and find the AT%XSYSTEMMODE=0,1,1,0 change to AT%XSYSTEMMODE=1,0,1,0, which means it did not really connect to NB-IoT network. I use nrf9160dk_at_client_2019-11-29_d3130d77.hex to do further test with following commands:

AT+CFUN=4
AT%XSYSTEMMODE=0,1,0,0
AT+CFUN=1

The LTE label on the LTE link monitor keeps showing yellow blinking and no network found.

but the AT+CESQ checking does show it find some signal like the log shown:

2020-01-13T21:54:37.359Z DEBUG modem << +CESQ: 99,99,255,255,255,255\x0D\x0A
2020-01-13T21:54:37.360Z DEBUG modem << OK\x0D\x0A
2020-01-13T21:54:38.343Z DEBUG modem >> AT+CESQ\x0D\x0A
2020-01-13T21:54:38.358Z DEBUG modem << +CESQ: 99,99,255,255,255,255\x0D\x0A
2020-01-13T21:54:38.359Z DEBUG modem << OK\x0D
2020-01-13T21:54:39.346Z DEBUG modem >> AT+CESQ\x0D\x0A
2020-01-13T21:54:39.360Z DEBUG modem << +CESQ: 99,99,255,255,255,255\x0D\x0A
2020-01-13T21:54:39.361Z DEBUG modem << OK\x0D
2020-01-13T21:54:39.654Z DEBUG modem << %CESQ: 70,3,8,1\x0D
2020-01-13T21:54:39.663Z DEBUG modem << +CEREG: 2,"A0F1","01043566",9\x0D\x0A
2020-01-13T21:54:40.340Z DEBUG modem >> AT+CESQ\x0D\x0A
2020-01-13T21:54:40.346Z DEBUG modem << +CESQ: 99,99,255,255,8,70\x0D\x0A
2020-01-13T21:54:40.347Z DEBUG modem << OK\x0D\x0A
2020-01-13T21:54:41.342Z DEBUG modem >> AT+CESQ\x0D\x0A
2020-01-13T21:54:41.359Z DEBUG modem << +CESQ: 99,99,255,255,8,70\x0D\x0A
2020-01-13T21:54:41.363Z DEBUG modem << OK\x0D
2020-01-13T21:54:42.340Z DEBUG modem >> AT+CESQ\x0D\x0A
2020-01-13T21:54:42.366Z DEBUG modem << +CESQ: 99,99,255,255,8,70\x0D\x0A
2020-01-13T21:54:42.374Z DEBUG modem << OK\x0D\x0A

A similar test with the LTE-

M network is completely fine.

I searched the former questions and did not find similar reports, maybe it is just a small mistake. I need some hits to find the problem, looking forward to getting replies.

Thanks in advance.

[Øyvind]

Hello, 

Yes, I can confirm that there are some issues with NB-IoT using iBasis. I am also seeing the issue here in Trondheim. 

The best solution at the moment is to ask Telenor for an NB-IoT (and LTE-M) activated SIM. 

Kind regards,
Øyvind