NRF_LOG printing through RTT does not print

[Erik Zilliacus]

Hi,

I have just recently started to develop an NRF52832 chip with Keil uVision 5.

My setup is the following:

PCA10028 Development kit connected to Feather NRF52832 bluefruit LE with SWD cable to debug pins

SDK 12.3.0

I have managed to develop and flash to the chip successfully during the course of one week without problems, but I haven't managed to get printing to the J-Link RTT viewer to work yet.

I am using the NRF_LOG functions to print simple test strings but nothing shows up on the RTT viewer. What I've done so far:

- Modified the sdk_config.h: (NRF_LOG_BACKEND_SERIAL_USES_RTT 1 , and NRF_LOG_ENABLED 1)

- With the J-Link RTT viewer: connected to USB port of Development kit successfully (SWD 4000 kHz). See picture below.

- Flashed a simple blink program just for testing NRF_LOG functionality (blinking works as it should, but no printing):

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int main(void)

{

NRF_LOG_INIT(NULL);

char string_on_stack[] = "stack";

NRF_LOG_INFO("%s",nrf_log_push(string_on_stack));

NRF_LOG_DEBUG("TESTING");

/* Configure board. */

bsp_board_leds_init();

uint32_t err_code;

while(true){

for (int i = 0; i < LEDS_NUMBER; i++)

{

NRF_LOG_INFO("%s",nrf_log_push(string_on_stack));

bsp_board_led_invert(i);

nrf_delay_ms(500);

}

}

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

int main(void)
{
	NRF_LOG_INIT(NULL);
	char string_on_stack[] = "stack";
	NRF_LOG_INFO("%s",nrf_log_push(string_on_stack));
	NRF_LOG_DEBUG("TESTING");

	/* Configure board. */
    bsp_board_leds_init();
	  uint32_t err_code;
	while(true){
			for (int i = 0; i < LEDS_NUMBER; i++)
		{

			NRF_LOG_INFO("%s",nrf_log_push(string_on_stack));
			bsp_board_led_invert(i);
			nrf_delay_ms(500);

		}
	}
	
}

I have followed the SDK documentation and tutorials trying to troubleshoot the problem without success. I am a beginner so I suspect I am missing something trivial.