UART, custom and AT commands

[anicare-tero]

Hi,

I have been trying to get UART working properly on my custom board but also on nRF9160 DK. I'm using only UART_0.

With CONFIG_USE_AT_HOST and without any uart code inside my own code, AT commands are working but if I wrote something else like "hi" to terminal, the device is giving a HARD FAULT.

hi
[0[00:01:23.622,528] [1B][1;31m<err> os: ***** HARD FAULT *****[1B][0m
[00:01:23.628,143] [1B][1;31m<err> os:   Fault escalation (see below)[1B][0m
[00:01:23.634,399] [1B][1;31m<err> os: ***** USAGE FAULT *****[1B][0m
[00:01:23.640,045] [1B][1;31m<err> os:   Stack overflow (context area not valid)[1B][0m
[00:01:23.647,216] [1B][1;31m<err> os: r0/a1:  0x2002c600  r1/a2:  0x00000001  r2/a3:  0x20027506[1B][0m
[00:01:23.655,883] [1B][1;31m<err> os: r3/a4:  0x2002c600 r12/ip:  0x000253a9 r14/lr:  0x000252f3[1B][0m
[00:01:23.664,550] [1B][1;31m<err> os:  xpsr:  0x00028e00[1B][0m
[00:01:23.669,769] [1B][1;31m<err> os: s[ 0]:  0x00000000  s[ 1]:  0x00000000  s[ 2]:  0x00000000  s[ 3]:  0x00000000[1B][0m
[00:01:23.680,175] [1B][1;31m<err> os: s[ 4]:  0x00000000  s[ 5]:  0x00000000  s[ 6]:  0x00000000  s[ 7]:  0x00000000[1B][0m
[00:01:23.690,612] [1B][1;31m<err> os: s[ 8]:  0x00000000  s[ 9]:  0x00000000  s[10]:  0x00000000  s[11]:  0x00000000[1B][0m
[00:01:23.701,019] [1B][1;31m<err> os: s[12]:  0x00000000  s[13]:  0x00000000  s[14]:  0x00000000  s[15]:  0x00000000[1B][0m
[00:01:23.711,456] [1B][1;31m<err> os: fpscr:  0x000109b1[1B][0m
[00:01:23.716,674] [1B][1;31m<err> os: Faulting instruction address (r15/pc): 0x2002c600[1B][0m
[00:01:23.724,548] [1B][1;31m<err> os: >>> ZEPHYR FATAL ERROR 2: Stack overflow on CPU 0[1B][0m
[00:01:23.732,421] [1B][1;31m<err> os: Current thread: 0x200229b0 (unknown)[1B][0m
Running main.c error handlerError of type ERROR_SYSTEM_FAULT: 2

With uart code from https://github.com/Rallare/fw-nrfconnect-nrf/blob/nrf9160_samples/samples/nrf9160/uart/ inside my own code, I'm able to write whatever I want to terminal and it echoes that back from uart_cb(). But AT commands are NOT working, the code is understanding them as just similar text like "hi" and is echoing them back and not doing anything with the modem.

So, do you have any idea how should I make them work together? My goal is to give my own commands but also AT commands to the device with only one UART peripheral.

Regards,
Tero

[Simon]

It seems like modem_connect() and modem_offline() are some custom functions. Could you upload your code? Then I can try to reproduce it on my side.

Best regards,

Simon

[anicare-tero]

I cleaned the code a little bit so there should not be any useless stuff for this case for now.

2626.test.rar

Regards,
Tero

[Simon]

In my case, the ETIMDEOUT comes from calling modem_connect() from main() as well as from debug_console.c→handle_custom_command()→modem_connect().

Could you check again and see if the same is happening to you, just to make sure we are on the same page.

Best regards,

Simon

[anicare-tero]

Hi Simon,

I checked it and it works when calling it from main(). Please notice that I'm using NB-IoT and no fallback.

CONFIG_LTE_NETWORK_MODE_NBIOT=y
CONFIG_LTE_NETWORK_USE_FALLBACK=n

Regards,
Tero

[Simon]

Okay, I will take a look at again.