User in Guernsey cannot connect to the network with NRF9160

[lzpons]

Hi,

I have a customer in Guernsey that received one of our Thingy91 hubs and he's not able to connect.

Here is some troubleshooting facts :

- when he moves to London the device connects successfully

- when he looks to the available networks locally with his iphone, there is actually an LTE network see snapshot.

- if he puts our SIM in his phone, it works properly establishing a connection.

- when he looks to the available networks through the Thingy:91 with the LTE Link Monitor using AT+COPS? command : nothing is reported

What may be wrong with this location? are there "special" LTE networks that the NRF9160 cannot see?

What troubleshooting would you suggest to move ahead?

Thanks for your help

LP

[Didrik Rokhaug]

Hi,

Is there LTE-M or NB-IoT coverage on Guernsey?

The nRF9160 only works with LTE-M and NB-IoT, and not "normal" LTE like a cell phone.

- when he looks to the available networks through the Thingy:91 with the LTE Link Monitor using AT+COPS? command : nothing is reported

This would indicate that there isn't LTE-M or NB-IoT (whichever the modem is configured to use) coverage at that location.

Best regards,

Didrik

[lzpons]

That's right, nothing reported with AT+COPS?  See the trace below.

To better understand the underlying topic, an LTE and an LTE-M network are two different protocols that do not necessarily go together?

It depends on how the overall network (or maybe the single antenna) are configured?

How can we check the coverage then? checking with a smartphone may be misleading since it will find 4G=LTE but not check for LTE-M

Is there any available documentation on this practical aspect? I am not finding it on the web.

LP

2022-12-13T09:36:22.369Z DEBUG Application data folder: C:\Users\user\AppData\Roaming\nrfconnect\pc-nrfconnect-linkmonitor
2022-12-13T09:36:22.466Z INFO Using nrf-device-lib-js version: 0.4.13
2022-12-13T09:36:22.466Z INFO Using nrf-device-lib version: 0.12.8
2022-12-13T09:36:22.466Z INFO Using nrfjprog DLL version: 10.16.0
2022-12-13T09:36:22.467Z INFO Using JLink version: JLink_V7.82a
2022-12-13T09:36:22.501Z DEBUG App pc-nrfconnect-linkmonitor v2.0.2 official
2022-12-13T09:36:22.501Z DEBUG App path: C:\Users\user\.nrfconnect-apps\node_modules\pc-nrfconnect-linkmonitor
2022-12-13T09:36:22.502Z DEBUG nRFConnect 3.12.0, required by the app is (^3.12.0)
2022-12-13T09:36:22.502Z DEBUG nRFConnect path: C:\Users\user\AppData\Local\Programs\nrfconnect\resources\app.asar
2022-12-13T09:36:22.502Z DEBUG HomeDir: C:\Users\user
2022-12-13T09:36:22.502Z DEBUG TmpDir: C:\Users\user\AppData\Local\Temp
2022-12-13T09:36:22.504Z INFO Installed JLink version does not match the provided version (V7.66a)
2022-12-13T09:36:30.205Z INFO Modem port is opened
2022-12-13T09:36:30.222Z DEBUG modem >> AT+CFUN?
2022-12-13T09:36:30.264Z DEBUG modem << +CFUN: 0
2022-12-13T09:36:30.269Z DEBUG modem << OK
2022-12-13T09:36:59.885Z DEBUG modem >> AT+CFUN=1
2022-12-13T09:36:59.937Z DEBUG modem << OK
2022-12-13T09:37:06.439Z DEBUG modem >> AT+CFUN?
2022-12-13T09:37:06.449Z DEBUG modem << +CFUN: 1
2022-12-13T09:37:06.469Z DEBUG modem << OK
2022-12-13T09:37:06.477Z DEBUG modem >> AT+CGSN=1
2022-12-13T09:37:06.488Z DEBUG modem << +CGSN: "352656101505934"
2022-12-13T09:37:06.494Z DEBUG modem << OK
2022-12-13T09:37:06.502Z DEBUG modem >> AT+CGMI
2022-12-13T09:37:06.517Z DEBUG modem << Nordic Semiconductor ASA
2022-12-13T09:37:06.520Z DEBUG modem << OK
2022-12-13T09:37:06.527Z DEBUG modem >> AT+CGMM
2022-12-13T09:37:06.536Z DEBUG modem << nRF9160-SICA
2022-12-13T09:37:06.538Z DEBUG modem << OK
2022-12-13T09:37:06.546Z DEBUG modem >> AT+CGMR
2022-12-13T09:37:06.554Z DEBUG modem << mfw_nrf9160_1.3.2
2022-12-13T09:37:06.557Z DEBUG modem << OK
2022-12-13T09:37:06.560Z INFO Nordic Semiconductor ASA nRF9160-SICA [mfw_nrf9160_1.3.2] SerNr: 352656101505934
2022-12-13T09:37:06.564Z DEBUG modem >> AT+CEMODE?
2022-12-13T09:37:06.575Z DEBUG modem << +CEMODE: 2
2022-12-13T09:37:06.578Z DEBUG modem << OK
2022-12-13T09:37:06.593Z DEBUG modem >> AT%XCBAND=?
2022-12-13T09:37:06.604Z DEBUG modem << %XCBAND: (1,2,3,4,5,8,12,13,18,19,20,25,26,28,66)
2022-12-13T09:37:06.608Z DEBUG modem << OK
2022-12-13T09:37:06.625Z DEBUG modem >> AT+CMEE?
2022-12-13T09:37:06.635Z DEBUG modem << +CMEE: 0
2022-12-13T09:37:06.637Z DEBUG modem << OK
2022-12-13T09:37:06.645Z DEBUG modem >> AT+CMEE=1
2022-12-13T09:37:06.651Z DEBUG modem << OK
2022-12-13T09:37:06.655Z DEBUG modem >> AT+CNEC?
2022-12-13T09:37:06.664Z DEBUG modem << +CNEC: 0
2022-12-13T09:37:06.666Z DEBUG modem << OK
2022-12-13T09:37:06.671Z DEBUG modem >> AT+CNEC=24
2022-12-13T09:37:06.678Z DEBUG modem << OK
2022-12-13T09:37:06.684Z DEBUG modem >> AT+CGEREP?
2022-12-13T09:37:06.693Z DEBUG modem << +CGEREP: 0,0
2022-12-13T09:37:06.695Z DEBUG modem << OK
2022-12-13T09:37:06.700Z DEBUG modem >> AT+CGDCONT?
2022-12-13T09:37:06.709Z DEBUG modem << OK
2022-12-13T09:37:06.714Z DEBUG modem >> AT+CGACT?
2022-12-13T09:37:06.720Z DEBUG modem << OK
2022-12-13T09:37:06.726Z DEBUG modem >> AT+CGEREP=1
2022-12-13T09:37:06.733Z DEBUG modem << OK
2022-12-13T09:37:06.738Z DEBUG modem >> AT+CIND=1,1,1
2022-12-13T09:37:06.745Z DEBUG modem << OK
2022-12-13T09:37:06.750Z DEBUG modem >> AT+CEREG=5
2022-12-13T09:37:06.760Z DEBUG modem << OK
2022-12-13T09:37:06.764Z DEBUG modem >> AT+CEREG?
2022-12-13T09:37:06.774Z DEBUG modem << +CEREG: 5,4
2022-12-13T09:37:06.778Z DEBUG modem << OK
2022-12-13T09:37:06.796Z DEBUG modem >> AT%CESQ=1
2022-12-13T09:37:06.804Z DEBUG modem << OK
2022-12-13T09:37:06.810Z DEBUG modem >> AT+CESQ
2022-12-13T09:37:06.820Z DEBUG modem << +CESQ: 99,99,255,255,255,255
2022-12-13T09:37:06.822Z DEBUG modem << OK
2022-12-13T09:37:06.834Z DEBUG modem >> AT%XSIM=1
2022-12-13T09:37:06.843Z DEBUG modem << OK
2022-12-13T09:37:06.849Z DEBUG modem >> AT%XSIM?
2022-12-13T09:37:06.860Z DEBUG modem << %XSIM: 1
2022-12-13T09:37:06.862Z DEBUG modem << OK
2022-12-13T09:37:06.872Z DEBUG modem >> AT+CPIN?
2022-12-13T09:37:06.882Z DEBUG modem << +CPIN: READY
2022-12-13T09:37:06.885Z DEBUG modem << OK
2022-12-13T09:37:06.898Z DEBUG modem >> AT+CPINR="SIM PIN"
2022-12-13T09:37:06.917Z DEBUG modem << +CPINR: "SIM PIN",3
2022-12-13T09:37:06.920Z DEBUG modem << OK
2022-12-13T09:37:06.934Z DEBUG modem >> AT+CIMI
2022-12-13T09:37:06.943Z DEBUG modem << 234500093370919
2022-12-13T09:37:06.946Z DEBUG modem << OK
2022-12-13T09:37:06.947Z INFO IMSIdentity: 234500093370919
2022-12-13T09:38:08.689Z DEBUG modem << +CEREG: 4
2022-12-13T09:40:25.786Z DEBUG modem >> AT+COPS=?
2022-12-13T09:40:26.795Z ERROR Error: 'AT+COPS=?
' timed out
2022-12-13T09:40:44.284Z DEBUG modem << +CEREG: 2
2022-12-13T09:41:17.932Z DEBUG modem << +CEREG: 4
2022-12-13T09:41:55.439Z DEBUG modem << +CEREG: 2
2022-12-13T09:43:04.800Z DEBUG modem << +CEREG: 4
2022-12-13T09:43:24.958Z DEBUG modem << +COPS:
2022-12-13T09:43:24.961Z DEBUG modem << OK
2022-12-13T09:46:27.658Z DEBUG modem >> AT+COPS=?
2022-12-13T09:46:59.168Z DEBUG modem << +CEREG: 2
2022-12-13T09:47:01.356Z DEBUG modem << +CEREG: 4
2022-12-13T09:47:44.749Z DEBUG modem << +CEREG: 2
2022-12-13T09:47:44.755Z DEBUG modem << +COPS:
2022-12-13T09:47:44.761Z DEBUG modem << OK
2022-12-13T09:47:44.771Z DEBUG modem >> AT+COPS?
2022-12-13T09:47:44.780Z DEBUG modem << +COPS: 1
2022-12-13T09:47:44.783Z DEBUG modem << OK
2022-12-13T09:48:18.300Z DEBUG modem << +CEREG: 4
2022-12-13T09:49:00.558Z DEBUG modem << +CEREG: 2
2022-12-13T09:50:10.201Z DEBUG modem << +CEREG: 4

[lzpons]

To be fully complete, it seems that one network supports NB-IOT, but you need to shift system mode to see it.

Here is that trace (bold commands are what was typed)

2022-12-13T12:07:49.618Z DEBUG modem << +CEREG: 2,"09CF","0002140A",9

2022-12-13T11:52:33.193Z DEBUG modem >> AT+CFUN?
2022-12-13T11:52:33.209Z DEBUG modem << +CFUN: 0
2022-12-13T11:52:33.212Z DEBUG modem << OK
2022-12-13T11:52:35.970Z DEBUG modem >> AT+CFUN?
2022-12-13T11:52:35.985Z DEBUG modem << +CFUN: 0
2022-12-13T11:52:35.994Z DEBUG modem << OK
2022-12-13T11:52:50.830Z DEBUG modem >> AT%XSYSTEMMODE=0,1,0,0
2022-12-13T11:52:50.850Z DEBUG modem << OK
2022-12-13T11:53:10.991Z DEBUG modem >> AT+CGDCONT=0,"IPV4V6","cdp.iot.t-mobile.nl"
2022-12-13T11:53:11.008Z DEBUG modem << OK
2022-12-13T11:53:29.295Z DEBUG modem >> AT+COPS=1,2,"23403",9
2022-12-13T11:53:29.310Z DEBUG modem << OK
2022-12-13T11:53:38.475Z DEBUG modem >> AT+CFUN=1
2022-12-13T11:53:38.522Z DEBUG modem << OK
2022-12-13T11:53:46.303Z DEBUG modem >> AT+CFUN?
2022-12-13T11:53:46.311Z DEBUG modem << +CFUN: 1
2022-12-13T11:53:46.318Z DEBUG modem << OK
2022-12-13T11:53:46.325Z DEBUG modem >> AT+CGSN=1
2022-12-13T11:53:46.334Z DEBUG modem << +CGSN: "352656101505934"
2022-12-13T11:53:46.336Z DEBUG modem << OK
2022-12-13T11:53:46.343Z DEBUG modem >> AT+CGMI
2022-12-13T11:53:46.355Z DEBUG modem << Nordic Semiconductor ASA
2022-12-13T11:53:46.357Z DEBUG modem << OK
2022-12-13T11:53:46.362Z DEBUG modem >> AT+CGMM
2022-12-13T11:53:46.372Z DEBUG modem << nRF9160-SICA
2022-12-13T11:53:46.375Z DEBUG modem << OK
2022-12-13T11:53:46.379Z DEBUG modem >> AT+CGMR
2022-12-13T11:53:46.389Z DEBUG modem << mfw_nrf9160_1.3.2
2022-12-13T11:53:46.392Z DEBUG modem << OK
2022-12-13T11:53:46.393Z INFO Nordic Semiconductor ASA nRF9160-SICA [mfw_nrf9160_1.3.2] SerNr: 352656101505934
2022-12-13T11:53:46.396Z DEBUG modem >> AT+CEMODE?
2022-12-13T11:53:46.406Z DEBUG modem << +CEMODE: 0
2022-12-13T11:53:46.412Z DEBUG modem << OK
2022-12-13T11:53:46.423Z DEBUG modem >> AT%XCBAND=?
2022-12-13T11:53:46.440Z DEBUG modem << %XCBAND: (1,2,3,4,5,8,12,13,17,19,20,25,26,28,66)
2022-12-13T11:53:46.442Z DEBUG modem << OK
2022-12-13T11:53:46.450Z DEBUG modem >> AT+CMEE?
2022-12-13T11:53:46.457Z DEBUG modem << +CMEE: 0
2022-12-13T11:53:46.460Z DEBUG modem << OK
2022-12-13T11:53:46.466Z DEBUG modem >> AT+CMEE=1
2022-12-13T11:53:46.472Z DEBUG modem << OK
2022-12-13T11:53:46.477Z DEBUG modem >> AT+CNEC?
2022-12-13T11:53:46.489Z DEBUG modem << +CNEC: 0
2022-12-13T11:53:46.491Z DEBUG modem << OK
2022-12-13T11:53:46.496Z DEBUG modem >> AT+CNEC=24
2022-12-13T11:53:46.506Z DEBUG modem << OK
2022-12-13T11:53:46.511Z DEBUG modem >> AT+CGEREP?
2022-12-13T11:53:46.522Z DEBUG modem << +CGEREP: 0,0
2022-12-13T11:53:46.525Z DEBUG modem << OK
2022-12-13T11:53:46.529Z DEBUG modem >> AT+CGDCONT?
2022-12-13T11:53:46.540Z DEBUG modem << +CGDCONT: 0,"IPV4V6","cdp.iot.t-mobile.nl","",0,0
2022-12-13T11:53:46.542Z DEBUG modem << OK
2022-12-13T11:53:46.550Z DEBUG modem >> AT+CGACT?
2022-12-13T11:53:46.559Z DEBUG modem << +CGACT: 0,0
2022-12-13T11:53:46.561Z DEBUG modem << OK
2022-12-13T11:53:46.574Z DEBUG modem >> AT+CGEREP=1
2022-12-13T11:53:46.582Z DEBUG modem << OK
2022-12-13T11:53:46.589Z DEBUG modem >> AT+CIND=1,1,1
2022-12-13T11:53:46.597Z DEBUG modem << OK
2022-12-13T11:53:46.601Z DEBUG modem >> AT+CEREG=5
2022-12-13T11:53:46.610Z DEBUG modem << OK
2022-12-13T11:53:46.613Z DEBUG modem >> AT+CEREG?
2022-12-13T11:53:46.623Z DEBUG modem << +CEREG: 5,4
2022-12-13T11:53:46.627Z DEBUG modem << OK
2022-12-13T11:53:46.634Z DEBUG modem >> AT%CESQ=1
2022-12-13T11:53:46.642Z DEBUG modem << OK
2022-12-13T11:53:46.649Z DEBUG modem >> AT+CESQ
2022-12-13T11:53:46.657Z DEBUG modem << +CESQ: 99,99,255,255,255,255
2022-12-13T11:53:46.661Z DEBUG modem << OK
2022-12-13T11:53:46.675Z DEBUG modem >> AT%XSIM=1
2022-12-13T11:53:46.682Z DEBUG modem << OK
2022-12-13T11:53:46.689Z DEBUG modem >> AT%XSIM?
2022-12-13T11:53:46.697Z DEBUG modem << %XSIM: 1
2022-12-13T11:53:46.699Z DEBUG modem << OK
2022-12-13T11:53:46.711Z DEBUG modem >> AT+CPIN?
2022-12-13T11:53:46.723Z DEBUG modem << +CPIN: READY
2022-12-13T11:53:46.725Z DEBUG modem << OK
2022-12-13T11:53:46.731Z DEBUG modem >> AT+CPINR="SIM PIN"
2022-12-13T11:53:46.753Z DEBUG modem << +CPINR: "SIM PIN",3
2022-12-13T11:53:46.754Z DEBUG modem << OK
2022-12-13T11:53:46.761Z DEBUG modem >> AT+CIMI
2022-12-13T11:53:46.768Z DEBUG modem << 234030140071218
2022-12-13T11:53:46.770Z DEBUG modem << OK
2022-12-13T11:53:46.771Z INFO IMSIdentity: 234030140071218
2022-12-13T11:53:55.041Z DEBUG modem << %CESQ: 48,2,17,2
2022-12-13T11:53:55.075Z DEBUG modem << +CEREG: 2,"09CF","00021408",9
2022-12-13T11:53:58.674Z DEBUG modem << %CESQ: 48,2,22,3
2022-12-13T11:54:03.490Z DEBUG modem << %CESQ: 48,2,17,2
2022-12-13T11:54:13.328Z DEBUG modem << %CESQ: 49,2,22,3
2022-12-13T11:54:19.810Z DEBUG modem << %CESQ: 49,2,17,2
2022-12-13T11:54:37.379Z DEBUG modem << %CESQ: 49,2,22,3
2022-12-13T11:54:55.208Z DEBUG modem << %CESQ: 49,2,16,2
2022-12-13T11:55:04.751Z DEBUG modem << %CESQ: 48,2,21,3
2022-12-13T11:55:08.771Z DEBUG modem << %CESQ: 47,2,14,2
2022-12-13T11:55:28.678Z DEBUG modem << %CESQ: 46,2,19,2
2022-12-13T11:55:38.740Z DEBUG modem << %CESQ: 45,2,14,2
2022-12-13T11:55:49.083Z DEBUG modem << %CESQ: 47,2,19,2
2022-12-13T11:55:56.661Z DEBUG modem << %CESQ: 46,2,13,1
2022-12-13T11:56:17.164Z DEBUG modem << %CESQ: 47,2,18,2
2022-12-13T11:56:29.930Z DEBUG modem << %CESQ: 46,2,13,1
2022-12-13T11:56:37.798Z DEBUG modem << %CESQ: 46,2,21,3
2022-12-13T11:56:42.742Z DEBUG modem << %CESQ: 47,2,14,2
2022-12-13T11:56:46.109Z DEBUG modem >> AT+COPS=?
2022-12-13T11:58:25.319Z DEBUG modem << %CESQ: 48,2,19,2
2022-12-13T11:58:53.290Z DEBUG modem << %CESQ: 48,2,14,2
2022-12-13T11:58:59.003Z DEBUG modem << +COPS: (1,"","","23403",9)
2022-12-13T11:58:59.006Z DEBUG modem << OK
2022-12-13T11:58:59.027Z DEBUG modem >> AT+COPS?
2022-12-13T11:58:59.052Z DEBUG modem << +COPS: 1
2022-12-13T11:58:59.054Z DEBUG modem << OK
2022-12-13T11:59:01.005Z DEBUG modem << %CESQ: 48,2,19,2
2022-12-13T11:59:24.200Z DEBUG modem << %CESQ: 47,2,11,1
2022-12-13T11:59:26.760Z DEBUG modem << %CESQ: 42,2,9,1
2022-12-13T12:00:20.521Z DEBUG modem << %CESQ: 45,2,15,2
2022-12-13T12:00:38.440Z DEBUG modem << %CESQ: 42,2,10,1
2022-12-13T12:01:42.423Z DEBUG modem << %CESQ: 44,2,15,2
2022-12-13T12:01:49.967Z DEBUG modem << %CESQ: 43,2,9,1
2022-12-13T12:01:52.682Z DEBUG modem << %CESQ: 43,2,15,2
2022-12-13T12:02:13.162Z DEBUG modem << %CESQ: 43,2,10,1
2022-12-13T12:02:20.842Z DEBUG modem << %CESQ: 44,2,16,2
2022-12-13T12:02:28.345Z DEBUG modem << %CESQ: 43,2,9,1
2022-12-13T12:02:31.082Z DEBUG modem << %CESQ: 42,2,14,2
2022-12-13T12:03:17.162Z DEBUG modem << %CESQ: 42,2,9,1
2022-12-13T12:03:40.202Z DEBUG modem << %CESQ: 43,2,15,2
2022-12-13T12:03:55.563Z DEBUG modem << %CESQ: 41,2,10,1
2022-12-13T12:04:23.723Z DEBUG modem << %CESQ: 44,2,16,2
2022-12-13T12:04:31.226Z DEBUG modem << %CESQ: 44,2,11,1
2022-12-13T12:04:33.963Z DEBUG modem << %CESQ: 45,2,16,2
2022-12-13T12:04:51.707Z DEBUG modem << %CESQ: 44,2,8,1
2022-12-13T12:04:54.444Z DEBUG modem << %CESQ: 45,2,18,2
2022-12-13T12:05:35.250Z DEBUG modem << %CESQ: 46,2,13,1

[Didrik Rokhaug]

lzpons said:

To better understand the underlying topic, an LTE and an LTE-M network are two different protocols that do not necessarily go together?

Correct. "Normal" LTE and LTE-M (and NB-IoT) are all different.

lzpons said:

How can we check the coverage then? checking with a smartphone may be misleading since it will find 4G=LTE but not check for LTE-M

Is there any available documentation on this practical aspect? I am not finding it on the web.

One answer is of course to go to the location and check.

Other than that, it will vary from location to location and carrier to carrier.

The GSMA have a deployment map, but it only shows deployment on a national level :https://www.gsma.com/iot/deployment-map/

For more local data, you typically need to see if the local carrier has a coverage map. E.g. this one for Telenor in Norway https://www.telenor.no/bedrift/iot/dekning/ (the website is in Norwegian)

lzpons said:

To be fully complete, it seems that one network supports NB-IOT, but you need to shift system mode to see it.

Yes, if only one mode is enabled with %XSYSTEMMODE, the modem will only search for networks of that kind.

As you say, the modem finds one network, but it doesn't look like it is able to connect to it.

However, I am not able to see why the connection fails from the log.

Could you take a modem trace, to help me investigate why the connection fails?

[lzpons]

Thank you very much Didrik for those explanations. They are really helpful and give us some guidance both on network configuration and also methods to run troubleshooting.

I am new setting up modem trace, so will go through this task and and post back the result.

[lzpons]

For the trace collection I would like to use a "standard" configuration (out of my own app). Looking to the Nordic documentation I've found that it could be possible to directly configure a Thingy:91 through MCUBoot following those steps

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/ug_thingy91_gsg.html#updating-the-conn-bridge-52840

And installing the following files:

* img_fota_dfu_hex/debug/thingy91_asset_tracker_v2_debug_2022-12-08_188a1603.hex
  Asset tracker v2 firmware for nRF9160, modem debug enabled, NB-Iot and LTE-M network modes

* img_fota_dfu_hex/thingy91_nrf52_connectivity_bridge_2022-12-08_188a1603.hex                     
  Connectivity bridge for the nrf52

* mfw_nrf9160_1.3.3.zip                                                                           
  Modem firmware, updated through nRF Connect for Desktop

Is this all right?

(trace collector produces a bin file so I have no means to check what it's doing..)