I'm using nrf51dk board and nrf_log came out correctly on my RTT terminal with built in module. After that I use debug port (P20) to program to my custom module. I've vdd, gnd, swdio and swdclk connected to my custom module and everything functions properly. However, my nrf_logs are not coming out to my terminal. Does logger module uses uart lines? If so, is there a way I can get logs another way? Meaning all I want to connect to my module is using 4 lines (vdd,gnd, swdio and swdclk). Or my settings in my sdk_config is incorrect. Thanks
From what I see here you need 5 additional dedicated lines for Tracing functionality which seems not accessible on P20 debug port of nRF5x DK board with SEGGER J-Link OB. So I'm afraid you cannot use it for Tracing on external nRF52 chip, you would need some more expensive debugging HW probe...
thank you for your answer. I've Segger jlink stand alone programmer and maybe I can use it to get debug logs correct.
I was trying to verify my answer by looking to nRF52 DK schematics and PCB layout but I guess it's true. This tutorial suggests that SEGGER debuggers need these additional lines. I see that IMCU_xxx lines on nRF52 DK are accessible but only through special 10-pin needle connector (not having name printed on PCB, it's close to SEGGER J-Link Atmel MCU, on the way to nRF52832 chip...). So in the end you might be able to combine that with P20/P19 ports but I don't see the way how to do it easily.
And this page describes which GPIO lines are having TRACE function.
thank you for your answer. It was very helpful.