Thingy91 Asset Tracker demo: stuck at no LTE connection

RE: Thingy91 Asset Tracker demo: stuck at no LTE connection

Øyvind — Tue, 29 Jun 2021 07:54:17 GMT

Thanks for the feedback! No news yet but will update you as soon as I have an update,

Kind regards,
Øyvind

RE: Thingy91 Asset Tracker demo: stuck at no LTE connection

bluebeam — Tue, 29 Jun 2021 02:28:28 GMT

I got the AT&T SIM card for their LTE-M service. I put the card in the Thingy91 and power it on. It just works. I'm able to connect to LTE-M network and send data to my nrfcloud account.

So something is wrong about the iBasis setup. They'll need to figure that out.

RE: Thingy91 Asset Tracker demo: stuck at no LTE connection

Øyvind — Wed, 23 Jun 2021 09:40:38 GMT

Hello,

[quote user="naiqiang"]But meanwhile I'm puzzled why the iBasis SIM card doesn't work. iBasis website says it has U.S. national wide LTE-M support. That is supposed to make developer ramp up easier. Why it doesn't work?[/quote]

Yes, I'm a little puzzled by this myself. I have contacted iBasis to see what can cause this issue. Can you please issue the AT Command %XICCID and send it along with the timestamp in a PM to me?

[quote user="naiqiang"]Also what do you think about the device not provisioned issue? Is that because the device hasn't connected yet and once it can connect the problem will go away?[/quote]

Correct, as the device is not connected to the network, it is not able to connect to the nRF Cloud to provision.

Kind regards,
Øyvind

RE: Thingy91 Asset Tracker demo: stuck at no LTE connection

bluebeam — Tue, 22 Jun 2021 22:27:42 GMT

Thanks for your prompt response.

We have AT&T, T-Mobile and Verizon here. They all claim to have either LTE-M or NB-Iot support.

I'll get this card and give it try: https://marketplace.att.com/products/att-iot-dataplans-lte-m-us

I'll come back and update whether it works or not.

But meanwhile I'm puzzled why the iBasis SIM card doesn't work. iBasis website says it has U.S. national wide LTE-M support. That is supposed to make developer ramp up easier. Why it doesn't work?

Also what do you think about the device not provisioned issue? Is that because the device hasn't connected yet and once it can connect the problem will go away?

Thanks!

RE: Thingy91 Asset Tracker demo: stuck at no LTE connection

Øyvind — Tue, 22 Jun 2021 07:35:31 GMT

Hi bluebeam,

Sorry to hear you are facing these issues. Thanks for providing valuable information to find the root cause of this issue.

[quote user=""]I'm here at US west coast with pretty good LTE signal. Cell phone shows 3 or 4 bars. iBasis's website says we're covered with LTE-M.[/quote]

What network does your cell phone connect to?

Based on the CEREG information throughout the logs:

//Connecting to LTE-M
+CEREG: 2,"2C46","014B8517",7,0,11,"11100000","11100000"
+CNEC_EMM: 15

+CEREG: 4,"FFFE","FFFFFFFF",7,0,15,"11100000","11100000"
+CEREG: 2,"2C46","014B8517",7,0,15,"11100000","11100000"
+CNEC_EMM: 11

lte_lc: Using fallback network mode
//Connecting to NB-IoT
+CEREG: 2,"EB08","014AF3CA",9,0,15,"11100000","11100000"
+CNEC_EMM: 11

+CEREG: 2,"9240","066E4D39",9,0,15,"11100000","11100000"
+CNEC_EMM: 15

The network that the iBasis SIM is trying to connect (Roaming) rejects the connection. The device tries for a given time to connect to LTE-M network. It then shifts over to NB-IoT. Both network rejects. See +CEREG chapter in the AT Command Reference guide.

From 3GPP TS 24.301 Annex A:

Cause #11 – PLMN not allowed
This EMM cause is sent to the UE if it requests service, or if the network initiates a detach request, in a PLMN
where the UE, by subscription or due to operator determined barring, is not allowed to operate.


Cause #15 – No suitable cells in tracking area
This EMM cause is sent to the UE if it requests service, or if the network initiates a detach request, in a tracking
area where the UE, by subscription, is not allowed to operate, but when it should find another allowed tracking
area or location area in the same PLMN or an equivalent PLMN.
NOTE 3: Cause #15 and cause #12 differ in the fact that cause #12 does not trigger the UE to search for another
allowed tracking area on the same PLMN.

Can please contact your local network provider and ask for a SIM that supports LTE-M

Kind regards,
Øyvind