lpuart with log enabled

RE: lpuart with log enabled

kclauah — Tue, 26 Oct 2021 01:50:05 GMT

Wow, that not only solve my problem but also showcase how to probably debug a program.

Thank you for your excellent explanation, Simon.

RE: lpuart with log enabled

Simon — Mon, 25 Oct 2021 11:47:31 GMT

The solution is to set CONFIG_LOG_PROCESS_THREAD_STACK_SIZE=8192

Explanation:

First I added CONFIG_THREAD_NAME=y to your samples prj.conf
Then I ran your sample, and got the following output:

[00:00:01.865,539] <inf> app: Received data 5 bytes
[00:00:02.269,866] <err> os: ***** MPU FAULT *****
[00:00:02.269,866] <err> os:   Stacking error (context area might be not valid)
[00:00:02.269,897] <err> os: r0/a1:  0xe5b87cf6  r1/a2:  0x5889934f  r2/a3:  0xfdf17dfc
[00:00:02.269,897] <err> os: r3/a4:  0x67cba936 r12/ip:  0x7fa9b996 r14/lr:  0x004d4b6e
[00:00:02.269,927] <err> os:  xpsr:  0x61000000
[00:00:02.269,927] <err> os: Faulting instruction address (r15/pc): 0x000046ac
[00:00:02.269,958] <err> os: >>> ZEPHYR FATAL ERROR 2: Stack overflow on CPU 0
[00:00:02.269,989] <err> os: Current thread: 0x200001d0 (logging)
[00:00:02.667,999] <err> fatal_error: Resetting system

You can see that a stack overflow happened, this is probably due to the config CONFIG_NO_OPTIMIZATIONS=y, which I didn't have in my sample. Which will turn off optimizations, and the code will occupy more memory.
Since I enabled CONFIG_THREAD_NAME, I could see that the logging thread caused the issue (Current thread: 0x200001d0 (logging))
Next, I increased the stack size of the logging thread by adding CONFIG_LOG_PROCESS_THREAD_STACK_SIZE=8192 to the prj.conf file and the issue disappeared

Best regards,

Simon

RE: lpuart with log enabled

kclauah — Mon, 25 Oct 2021 01:36:59 GMT

Hi, I am sorry to bother you.

Would you mind to have a look on my project?

I think I have modified the project exactly like you have mentioned.

devzone.nordicsemi.com/.../lpuart.7z

Thank you so much!

RE: lpuart with log enabled

Simon — Fri, 22 Oct 2021 12:37:58 GMT

I was able to get RTT Log (seems like that is what you're trying to do) to work with the nrf52 DK nRF52832 in the following manner:

Modify the lpuart accordingly:

https://github.com/nrfconnect/sdk-nrf/compare/v1.7.0...simon-iversen:lpuart_rtt_log

Connect P0.22 to P0.23 and P0.24 to P0.25
Build the sample with nrf52dk_nrf52832
Open RTT viewer on computer and flash the sample to the chip

Best regards,

Simon

RE: lpuart with log enabled

Simon — Thu, 21 Oct 2021 23:09:25 GMT

Hello,

I'll take a look at this tomorrow.

Best regards,

Simon