NB-IoT - nRF91DK

[dival]

Hi,

For asset tracker v2, it can detect the network and connect to it, and when it cannot connect to the nrf cloud, it disconnects. To be more specific, it disconnects from the connected network and starts searching for a new network.

I thought perhaps it was a connectivity issue, and I tried using AT client program which was able to detect to the network, and connect to the network, however when I tried to ping using the following AT command: AT#XPING="www.google.com",45,5000,5,1000 I got: Error: AT#XPING="www.google.com",45,5000,5,1000 failed: phone failure. However, the ping fails. 

2022-11-21T10:30:29.786Z DEBUG modem << +CESQ: 99,99,255,255,34,91
2022-11-21T10:30:29.789Z DEBUG modem << OK
2022-11-21T10:31:01.507Z DEBUG modem >> AT+CESQ
2022-11-21T10:31:01.521Z DEBUG modem << +CESQ: 99,99,255,255,34,91
2022-11-21T10:31:01.524Z DEBUG modem << OK
2022-11-21T10:31:20.996Z DEBUG modem >> AT#XCONNECT="google.com",80
2022-11-21T10:31:21.012Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:31:21.017Z ERROR Error: AT#XCONNECT="google.com",80
failed: phone failure
2022-11-21T10:31:29.771Z DEBUG modem >> AT+CESQ
2022-11-21T10:31:29.786Z DEBUG modem << +CESQ: 99,99,255,255,34,91
2022-11-21T10:31:29.792Z DEBUG modem << OK
2022-11-21T10:31:31.052Z DEBUG modem >> AT#XSOCKET=?
2022-11-21T10:31:31.066Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:31:31.070Z ERROR Error: AT#XSOCKET=?
failed: phone failure
2022-11-21T10:31:37.467Z DEBUG modem >> AT#XSOCKET=?
2022-11-21T10:31:37.490Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:31:37.494Z ERROR Error: AT#XSOCKET=?
failed: phone failure
2022-11-21T10:31:40.383Z DEBUG modem >> AT#XSOCKET?
2022-11-21T10:31:40.397Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:31:40.400Z ERROR Error: AT#XSOCKET?
failed: phone failure
2022-11-21T10:32:01.505Z DEBUG modem >> AT+CESQ
2022-11-21T10:32:01.520Z DEBUG modem << +CESQ: 99,99,255,255,34,91
2022-11-21T10:32:01.523Z DEBUG modem << OK
2022-11-21T10:32:05.500Z DEBUG modem >> AT#XUDPSVR=1,3442
2022-11-21T10:32:05.516Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:32:05.519Z ERROR Error: AT#XUDPSVR=1,3442
failed: phone failure
2022-11-21T10:32:31.516Z DEBUG modem >> AT+CESQ
2022-11-21T10:32:31.542Z DEBUG modem << +CESQ: 99,99,255,255,33,91
2022-11-21T10:32:31.546Z DEBUG modem << OK
2022-11-21T10:32:59.770Z DEBUG modem >> AT+CESQ
2022-11-21T10:32:59.788Z DEBUG modem << +CESQ: 99,99,255,255,34,91
2022-11-21T10:32:59.791Z DEBUG modem << OK
2022-11-21T10:33:07.868Z DEBUG modem >> AT#XCONNECT="google.com",80
2022-11-21T10:33:07.886Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:33:07.892Z ERROR Error: AT#XCONNECT="google.com",80
failed: phone failure
2022-11-21T10:33:29.773Z DEBUG modem >> AT+CESQ
2022-11-21T10:33:29.787Z DEBUG modem << +CESQ: 99,99,255,255,34,91
2022-11-21T10:33:29.791Z DEBUG modem << OK
2022-11-21T10:33:29.814Z DEBUG modem >> AT#XMQTTCON=1,"xxx","xxx","xxx","xxx.xxx.com",1883
2022-11-21T10:33:29.832Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:33:29.836Z ERROR Error: AT#XMQTTCON=1,"xxx","xxx","xxx","xxx.xxx.com",1883
failed: phone failure
2022-11-21T10:33:43.352Z DEBUG modem >> AT-CIPPING
2022-11-21T10:33:43.366Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:33:43.369Z ERROR Error: AT-CIPPING
failed: phone failure
2022-11-21T10:33:45.064Z DEBUG modem >> AT-CIPPING?
2022-11-21T10:33:45.081Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:33:45.085Z ERROR Error: AT-CIPPING?
failed: phone failure
2022-11-21T10:33:45.637Z DEBUG modem >> AT-CIPPING
2022-11-21T10:33:45.651Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:33:45.654Z ERROR Error: AT-CIPPING
failed: phone failure
2022-11-21T10:33:54.319Z DEBUG modem >> AT+CGPADDR
2022-11-21T10:33:54.340Z DEBUG modem << +CGPADDR: 0,"172.16.0.2"
2022-11-21T10:33:54.347Z DEBUG modem << OK
2022-11-21T10:33:55.266Z DEBUG modem >> AT+CGPADDR
2022-11-21T10:33:55.281Z DEBUG modem << +CGPADDR: 0,"172.16.0.2"
2022-11-21T10:33:55.285Z DEBUG modem << OK
2022-11-21T10:33:55.581Z DEBUG modem >> AT+CGPADDR
2022-11-21T10:33:55.596Z DEBUG modem << +CGPADDR: 0,"172.16.0.2"
2022-11-21T10:33:55.601Z DEBUG modem << OK
2022-11-21T10:33:55.740Z DEBUG modem >> AT+CGPADDR
2022-11-21T10:33:55.754Z DEBUG modem << +CGPADDR: 0,"172.16.0.2"
2022-11-21T10:33:55.757Z DEBUG modem << OK
2022-11-21T10:33:55.871Z DEBUG modem >> AT+CGPADDR
2022-11-21T10:33:55.888Z DEBUG modem << +CGPADDR: 0,"172.16.0.2"
2022-11-21T10:33:55.891Z DEBUG modem << OK
2022-11-21T10:33:56.010Z DEBUG modem >> AT+CGPADDR
2022-11-21T10:33:56.034Z DEBUG modem << +CGPADDR: 0,"172.16.0.2"
2022-11-21T10:33:56.040Z DEBUG modem << OK
2022-11-21T10:33:56.122Z DEBUG modem >> AT+CGPADDR
2022-11-21T10:33:56.136Z DEBUG modem << +CGPADDR: 0,"172.16.0.2"
2022-11-21T10:33:56.141Z DEBUG modem << OK
2022-11-21T10:33:56.271Z DEBUG modem >> AT+CGPADDR
2022-11-21T10:33:56.286Z DEBUG modem << +CGPADDR: 0,"172.16.0.2"
2022-11-21T10:33:56.290Z DEBUG modem << OK
2022-11-21T10:34:01.510Z DEBUG modem >> AT+CESQ
2022-11-21T10:34:01.524Z DEBUG modem << +CESQ: 99,99,255,255,34,91
2022-11-21T10:34:01.527Z DEBUG modem << OK
2022-11-21T10:34:19.817Z DEBUG modem >> cloud connect
2022-11-21T10:34:19.831Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:34:19.835Z ERROR Error: cloud connect
failed: phone failure
2022-11-21T10:34:31.512Z DEBUG modem >> AT+CESQ
2022-11-21T10:34:31.529Z DEBUG modem << +CESQ: 99,99,255,255,34,91
2022-11-21T10:34:31.537Z DEBUG modem <<
2022-11-21T10:34:31.542Z DEBUG modem << OK
2022-11-21T10:35:01.515Z DEBUG modem >> AT+CESQ
2022-11-21T10:35:01.530Z DEBUG modem << +CESQ: 99,99,255,255,34,92
2022-11-21T10:35:01.533Z DEBUG modem << OK
2022-11-21T10:35:31.514Z DEBUG modem >> AT+CESQ
2022-11-21T10:35:31.530Z DEBUG modem << +CESQ: 99,99,255,255,34,92
2022-11-21T10:35:31.536Z DEBUG modem <<
2022-11-21T10:35:31.538Z DEBUG modem << OK
2022-11-21T10:36:01.506Z DEBUG modem >> AT+CESQ
2022-11-21T10:36:01.521Z DEBUG modem << +CESQ: 99,99,255,255,33,91
2022-11-21T10:36:01.524Z DEBUG modem << OK
2022-11-21T10:36:29.770Z DEBUG modem >> AT+CESQ
2022-11-21T10:36:29.790Z DEBUG modem << +CESQ: 99,99,255,255,34,92
2022-11-21T10:36:29.795Z DEBUG modem << OK
2022-11-21T10:36:30.455Z DEBUG modem >> AT#XPING="www.google.com",45,5000,5,1000
2022-11-21T10:36:30.472Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:36:30.476Z ERROR Error: AT#XPING="www.google.com",45,5000,5,1000
failed: phone failure
2022-11-21T10:36:36.811Z DEBUG modem >> AT+CFUN=1
2022-11-21T10:36:36.824Z DEBUG modem << OK
2022-11-21T10:36:41.094Z DEBUG modem >> AT#XPING="www.google.com",45,5000,5,1000
2022-11-21T10:36:41.111Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:36:41.114Z ERROR Error: AT#XPING="www.google.com",45,5000,5,1000
failed: phone failure
2022-11-21T10:36:44.684Z DEBUG modem >> AT+XPING="www.google.com",45,5000,5,1000
2022-11-21T10:36:44.703Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:36:44.705Z ERROR Error: AT+XPING="www.google.com",45,5000,5,1000
failed: phone failure
2022-11-21T10:36:49.321Z DEBUG modem >> AT#XPING="www.google.com",45,5000,5,1000
2022-11-21T10:36:49.338Z DEBUG modem << +CME ERROR: 0
2022-11-21T10:36:49.343Z ERROR Error: AT#XPING="www.google.com",45,5000,5,1000
failed: phone failure
2022-11-21T10:36:59.772Z DEBUG modem >> AT+CESQ
2022-11-21T10:36:59.786Z DEBUG modem << +CESQ: 99,99,255,255,34,92
2022-11-21T10:36:59.791Z DEBUG modem << OK
2022-11-21T10:37:31.508Z DEBUG modem >> AT+CESQ
2022-11-21T10:37:31.522Z DEBUG modem << +CESQ: 99,99,255,255,34,92

[Øyvind]

Hello dival , 

You will need to choose either Asset Tracker v2 or Serial LTE Modem with regards to AT commands. The AT commands you are using, e.g. AT#XCONNECT is part of the SLM-specific AT commands. For the Asset Tracker v2 you will need to use the AT commands from nRF9160 AT Commands Reference commands. AT-CIPPING? is not a supported AT Command in our cellular modem.

A better way of testing your network issues will be to use Serial LTE Modem, at_client, or even Modem Shell. 

From the Wireshark modem trace you have attached the following AT command informs me that you are using a test network: %XMONITOR: 1,"Software Radio Systems LTE","srsLTE","99970","0007",9,4,"00000002",99,2399,84,31,"","11100000","11100000","00111110". This also shows that you are connected to your test network using NB-IoT, but from the wireshark log it does not look like you are connected out of the test network.

Have you verified that this network is connected to internet? As this network is yours please provide network logs showing that network traffic is routed correctly from the device to the internet through your test network.

From the modem trace collector, please provide the .bin file in order for us to see what is going on in the modem. The wireshark log (.pcapng) shows that you have bad signal qulity with AT+CESQ. 

If you device does not have an internet connection it will not be able to provision to nRF Cloud and you will not be able to add your device.

I will ask for the last time, but please acquire a standard network provided SIM to verify device functionality. It is very difficult for us to debug any test network that we are not familiar with. 

Kind regards,
Øyvind

[dival]

Hello Øyvind, thanks for getting back to me

When I tried with a Serial LTE monitor (AT client), I didn't observe any network problems, but I couldn't ping. I noticed I used the incorrect AT commands; thank you for pointing this up.

I'll see if I can use modem shell; it offers more testing choices, like pinging. I'm reading the following: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/nrf9160/modem_shell/README.html and I would just want to confirm with you, under "LTE link control", how are the APN set up? With AT commands AT+CGDCONT=1,"IP","<APN>" is this correct? I thought I would attempt to test by pinging by using MoSh command: ping to see if any problems occur, if so then the problem is with the network

I'll get back to you on the remaining aspects of debugging. Finally, I have not yet received a standard SIM card. I bought one and am waiting for it to come. I appreciate the assistance thus far.

Thanks.

[Øyvind]

dival said:

I'll get back to you on the remaining aspects of debugging.

Yes, please do. 

Where are you located? How is the network coverage in that area? What local network providers are available?

Kind regards,
Øyvind