Cannot get NB-IoT connection with nRF9160 DK

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Fri, 05 Jul 2019 11:41:37 GMT

I'll answer my own question: Yes! I succeeded to connect and register in nRF Cloud and I can now see the communicated data! Thanks to all that helped!

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Fri, 05 Jul 2019 11:08:24 GMT

I still can't get a connection with iBasis SIM card. Should I send AT+CGDCONT=1,"IP","<name>"? if yes, what should be instead of <name>?

Or another question: can I connect to nRFCLoud with a different SIM card?

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Fri, 05 Jul 2019 09:29:21 GMT

Thanks Martin: I included #define CONFIG_LTE_LEGACY_PCO_MODE on the top of lte_lc.c and now the Asset_Tracker does connect but not with the iBasics SIM card but with a 1nce SIM card.

I tried what you stated above and AT-CLIENT doesn't connect with iBasics SIM card either, although it works with the other.

So I'll go back to the version that is working and run from there. Thanks for you help. I'll study the tutorial you just sent me.

RE: Cannot get NB-IoT connection with nRF9160 DK

Martin Lesund — Fri, 05 Jul 2019 09:07:05 GMT

Hi Sergio,
You have to configure the prj.conf file located in the Application folder you are working with.

Please read through the tutorial on how to work with NCS for more details with regards to this.

Let us do some testing without modifying any applications to see if you actually can get an NB-iot connection:

1. Build and flash the default AT_Client sample

2. Open LTE LInk Monitor

3. Make sure the modem is off. (AT+CFUN=4)

4. Use the command: AT%XSYSTEMMODE=0,1,0,0

5. Use the command AT%XEPCO=0

6. Then turn on the modem AT+CFUN=1

Then use the AT+CFUN? while the "Automatic requests" is turned on:

So you can see all the responses from the modem with the command AT+CFUN?

Please share the LTE Link Monitor Log.

Best Regards,
Martin L.

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Fri, 05 Jul 2019 08:47:50 GMT

Regarding prj.conf, I can write whatever I like in the file, it doesn't cause an error or any change in the project. Therefore I am forced to conclude that it is not used, so all you r suggestions have zero effect... How can I make it work?

RE: Cannot get NB-IoT connection with nRF9160 DK

MJD093 — Tue, 02 Jul 2019 11:27:06 GMT

You will have errno.h. It's located in zephyr/lib/libc/minimal/include/errno.h.

Do try Martin's information on PCO_MODE.

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Tue, 02 Jul 2019 11:24:31 GMT

I have no file errno.h in the project! I have errno_private.h. Is is the same?

Regarding the network, We are using Deustche Telekom but I don't know what they allow. I'll have to check and get back to you.

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Tue, 02 Jul 2019 11:22:13 GMT

Let's clarify somethings first:

1.) I am using SES to compile and run the project. I can't find the file prj.conf in any of the files added to SES. Is this correct?

2.) After flashing with SES I stop the debugger and start nRF Connect: the logs you see are generated automatically by the nRF Connect. I send no commands to it.

3.) Did you insert the AT commands in your main.c? Can you show me how you did it and where you put it?

RE: Cannot get NB-IoT connection with nRF9160 DK

Martin Lesund — Tue, 02 Jul 2019 11:14:27 GMT

Hi Sergio,

Please set the

CONFIG_LTE_LEGACY_PCO_MODE=y

in prj.conf file.
This will set the modem to use PCO in PDN connection establishment, instead of ePCO.
There are some eNB and networks that do not support ePCO, yet.

Best regards,

Martin L.

RE: Cannot get NB-IoT connection with nRF9160 DK

MJD093 — Tue, 02 Jul 2019 11:05:42 GMT

Ok, so I delved deeper into nrf connect failed: 22

"nrf connect failed" is invoked by nrf_cloud_connect()
nrf_cloud_connect() invokes nct_connect()

nct_connect() invokes nct_mqtt_connect()

nct_mqtt_connect invokes mqtt_connect()

At some point this is outputting the errno 22, which is EINVAL or invalid arguement, see errno.h.

Question, does the network you are using allow you to use MQTT transport and DNS resolution? I ask as the Vodafone network here will not allow this on their NB-IoT network, they only allow whitelisted IP addresses so the asset_tracker application can not work for our development kit.

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Tue, 02 Jul 2019 10:44:54 GMT

Attached you will find the og file of a new attempt.devzone.nordicsemi.com/.../2019_2D00_07_2D00_02T10_5F00_39_5F00_16.863Z_2D00_log.txt

RE: Cannot get NB-IoT connection with nRF9160 DK

MJD093 — Tue, 02 Jul 2019 10:21:34 GMT

Ok so this is interesting, I do not get anything like what you get. I also added the CONFIG_LTE_NETWORK_MODE_NBIOT=y change to prj.conf and it did actually set the modem to NB-IoT. Without that CONFIG change, the device defaults to 1,0,0,0; so it does work as expected.

***** Booting Zephyr OS v1.14.99-ncs1 *****
Flash region		Domain		Permissions
00 0x00000 0x08000 	Secure		rwxl
01 0x08000 0x10000 	Non-Secure	rwxl
02 0x10000 0x18000 	Non-Secure	rwxl
03 0x18000 0x20000 	Non-Secure	rwxl
04 0x20000 0x28000 	Non-Secure	rwxl
05 0x28000 0x30000 	Non-Secure	rwxl
06 0x30000 0x38000 	Non-Secure	rwxl
07 0x38000 0x40000 	Non-Secure	rwxl
08 0x40000 0x48000 	Non-Secure	rwxl
09 0x48000 0x50000 	Non-Secure	rwxl
10 0x50000 0x58000 	Non-Secure	rwxl
11 0x58000 0x60000 	Non-Secure	rwxl
12 0x60000 0x68000 	Non-Secure	rwxl
13 0x68000 0x70000 	Non-Secure	rwxl
14 0x70000 0x78000 	Non-Secure	rwxl
15 0x78000 0x80000 	Non-Secure	rwxl
16 0x80000 0x88000 	Non-Secure	rwxl
17 0x88000 0x90000 	Non-Secure	rwxl
18 0x90000 0x98000 	Non-Secure	rwxl
19 0x98000 0xa0000 	Non-Secure	rwxl
20 0xa0000 0xa8000 	Non-Secure	rwxl
21 0xa8000 0xb0000 	Non-Secure	rwxl
22 0xb0000 0xb8000 	Non-Secure	rwxl
23 0xb8000 0xc0000 	Non-Secure	rwxl
24 0xc0000 0xc8000 	Non-Secure	rwxl
25 0xc8000 0xd0000 	Non-Secure	rwxl
26 0xd0000 0xd8000 	Non-Secure	rwxl
27 0xd8000 0xe0000 	Non-Secure	rwxl
28 0xe0000 0xe8000 	Non-Secure	rwxl
29 0xe8000 0xf0000 	Non-Secure	rwxl
30 0xf0000 0xf8000 	Non-Secure	rwxl
31 0xf8000 0x100000 	Non-Secure	rwxl

SRAM region		Domain		Permissions
00 0x00000 0x02000	Secure		rwxl
01 0x02000 0x04000	Secure		rwxl
02 0x04000 0x06000	Secure		rwxl
03 0x06000 0x08000	Secure		rwxl
04 0x08000 0x0a000	Secure		rwxl
05 0x0a000 0x0c000	Secure		rwxl
06 0x0c000 0x0e000	Secure		rwxl
07 0x0e000 0x10000	Secure		rwxl
08 0x10000 0x12000	Non-Secure	rwxl
09 0x12000 0x14000	Non-Secure	rwxl
10 0x14000 0x16000	Non-Secure	rwxl
11 0x16000 0x18000	Non-Secure	rwxl
12 0x18000 0x1a000	Non-Secure	rwxl
13 0x1a000 0x1c000	Non-Secure	rwxl
14 0x1c000 0x1e000	Non-Secure	rwxl
15 0x1e000 0x20000	Non-Secure	rwxl
16 0x20000 0x22000	Non-Secure	rwxl
17 0x22000 0x24000	Non-Secure	rwxl
18 0x24000 0x26000	Non-Secure	rwxl
19 0x26000 0x28000	Non-Secure	rwxl
20 0x28000 0x2a000	Non-Secure	rwxl
21 0x2a000 0x2c000	Non-Secure	rwxl
22 0x2c000 0x2e000	Non-Secure	rwxl
23 0x2e000 0x30000	Non-Secure	rwxl
24 0x30000 0x32000	Non-Secure	rwxl
25 0x32000 0x34000	Non-Secure	rwxl
26 0x34000 0x36000	Non-Secure	rwxl
27 0x36000 0x38000	Non-Secure	rwxl
28 0x38000 0x3a000	Non-Secure	rwxl
29 0x3a000 0x3c000	Non-Secure	rwxl
30 0x3c000 0x3e000	Non-Secure	rwxl
31 0x3e000 0x40000	Non-Secure	rwxl

Peripheral		Domain		Status
00 NRF_P0		Non-Secure	OK
01 NRF_CLOCK		Non-Secure	OK
02 NRF_RTC1		Non-Secure	OK
03 NRF_NVMC		Non-Secure	OK
04 NRF_UARTE1		Non-Secure	OK
05 NRF_UARTE2		Secure		SKIP
06 NRF_IPC		Non-Secure	OK
07 NRF_VMC		Non-Secure	OK
08 NRF_FPU		Non-Secure	OK
09 NRF_EGU1		Non-Secure	OK
10 NRF_EGU2		Non-Secure	OK
11 NRF_TWIM2		Non-Secure	OK
12 NRF_SPIM3		Non-Secure	OK
13 NRF_TIMER0		Non-Secure	OK
14 NRF_TIMER1		Non-Secure	OK
15 NRF_TIMER2		Non-Secure	OK
16 NRF_SAADC		Non-Secure	OK
17 NRF_GPIOTE1		Non-Secure	OK

SPM: NS image at 0x8000
SPM: NS MSP at 0x2002a4a8
SPM: NS reset vector at 0xf865
SPM: prepare to jump to Non-Secure image.
***** Booting Zephyr OS v1.14.99-ncs1 *****
Application started
LTE LC config ...
AT
OK
AT%XSYSTEMMODE?
%XSYSTEMMODE: 0,1,0,0
OK

Now, the two AT commands in this log were entered manually by me to check the LTE configuration. Under normal conditions they would not be there. As far as what I would expect to see, my device will get stuck on "LTE LC Config ..." as I actually don't have an NB-IoT network where I currently am.

Why are AT commands appearing in your log however; are you entering AT commands into the Link Monitor? As far as I can see in your log though, you are connected to a network. AT+CEREG? has returned the eNodeB identification number and returned the number 5 for stat (connected, roaming). However, you then invoke AT+COPS which then returns an AT+CEREG with the stat vaule of 0 which is "not registered", so your actually losing connection again after getting it.

This is also shown with CGEV returning Mobile Equipment Detach and your XSIM goes to 0 which means your UICC is no longer intialised???

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Tue, 02 Jul 2019 10:04:12 GMT

After searching the LTE became green but then the module made a reset.

AT+CPIN?
+CPIN: READY
OK
AT+CPINR="SIM PIN"
+CPINR: "SIM PIN",3
OK
AT+CIMI
901405100336032
OK
+CGEnrf_cloud_connect failed: 22
V: ME PDN ACT 0,0
+CNEC_ESM: 50,0
+CEREG: 5,"CB52","023AAF11",9
+CIND: "service",1
+CIND: "roam",1
AT+COPS=3,2
+CGEV: ME PDN DEACT 0
+CEREG: 0,"CB52","023AAF11",9
+CIND: "service",0
+CIND: "roam",0
+CGEV: ME DETACH
%CESQ: 255,0
%XSIM: 1
%XSIM: 0
OK
***** Booting Zephyr OS v1.14.99-ncs1 *****
AT+CGDCONT?
Flash region Domain Permissions
00 0x00000 0x08000 Secure rwxl
01 0x08000 0x10000 Non-Secure rwxl
02 0x10000 0x18000 Non-Secure rwxl
03 0x18000 0x20000 Non-Secure rwxl
04 0x20000 0x28000 Non-Secure rwxl
05 0x28000 0x30000 Non-Secure rwxl (...)

RE: Cannot get NB-IoT connection with nRF9160 DK

MJD093 — Tue, 02 Jul 2019 09:59:39 GMT

Thats... strange? It is in the master file as well as in my v0.4.0 release tag of the repos

https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/master/drivers/lte_link_control/lte_lc.c#L46

But anyway, at least your modem's XSYSTEMMODE is now configured correctly.

So what is it doing, can you post the serial log?

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Tue, 02 Jul 2019 09:53:40 GMT

I use a very good editor and I searched in all directories and all files of the project and I found only definitions for CONFIG_LTE_NETWORK_MODE_LTE_M and nonoe for NBIOT. I therefore replaced all

CONFIG_LTE_NETWORK_MODE_LTE_M by CONFIG_LTE_NETWORK_MODE_NBIOT.

Now after I run on SES and then check in nRF Connect, the XSYSTEMMODE is 0,1,0,2 which is correct. However it never connects...

What is wrong?

RE: Cannot get NB-IoT connection with nRF9160 DK

MJD093 — Tue, 02 Jul 2019 09:48:07 GMT

Ok great, so at least you know your set-up is working.

The next thing is to configure the asset tracker application to NB-IoT. Now you said you tried the CONFIG_LTE_NETWORK_MODE_NBIOT=y option and it didn't work. What exactly was the serial log for that attempt? Did it fail because of a connection error or because the human interaction part of the connection wasn't completed? Remember, there is a human interaction element to connecting the DK to nRF Cloud, it's not just flash the program and it will do the rest, you have to pair it to the nRF Cloud with button and switch inputs.

If it isn't changing the system set-up to NB-IoT, you can always try the direct approach and comment out both the LTE-M configuration for network_mode[] and the define check for NB-IoT in the lte_lc.c file and leave only the network_mode[] line for NB-IoT.

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Tue, 02 Jul 2019 09:41:24 GMT

The at_client example is working: I get LTE green in nRF Connect!

What is the next step?

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Tue, 02 Jul 2019 09:13:35 GMT

I will test it now: I'll let you know the result.

RE: Cannot get NB-IoT connection with nRF9160 DK

MJD093 — Tue, 02 Jul 2019 09:11:22 GMT

I know we have discussed this in the other question, but have you tried the at_client sample yet? I know this isn't what you are looking for as you would like the asset tracker but it is important to verify you can connect to a network or it will never work even with the correct configuration 😟

RE: Cannot get NB-IoT connection with nRF9160 DK

SergioT — Tue, 02 Jul 2019 09:08:01 GMT

The problem is I cannot get any connection with the Asset_Tracker example. I'd like to have one example that works so I can build on it. Our aim is to use NB-IoT for our application... Any tips?

RE: Cannot get NB-IoT connection with nRF9160 DK

MJD093 — Tue, 02 Jul 2019 09:01:11 GMT

Just to clarify, NB-IoT is a part of LTE. What you want to swap the radio configuration from LTE-M to LTE-NB. ;)