Softdevice - NRF_LOG_INFO not working.

[Neeraj Dhekale]

Hello All,

I am using nRF52840 DK and Segger with nRF5SDK 17.0.2 version. There are many examples that prints a NRF_LOG_INFO(). But I want to understand how to configure by myself. So I was trying to implement.

So I have added a below header:

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

static void log_init(void)
{
   ret_code_t err_code = NRF_LOG_INIT(NULL);
   APP_ERROR_CHECK(err_code);
   NRF_LOG_DEFAULT_BACKENDS_INIT();
}

and called it in main function

int main(void)
{
log_init();
 NRF_LOG_INFO(" Hello ");

}

Added nrf_log_backend_rtt.c file in nRF_Log folder Also defined below in sdk_config.h file

#define NRF_LOG_BACKEND_RTT_ENABLED 1

#define NRF_LOG_ENABLED 1

But still I am getting below error:

SEGGER_RTT_Conf.h: No such file or directory

Also I was checking on forum about the same error and people asked to add ../../../../../../external/segger_rtt; In user include directory but I have also tried to do the same. But got another error

undefined reference to `nrf_log_default_backends_init'

I am not sure what I am missing to do?

I am attaching the screenshot for reference.

Please help me.

Thanks in advance.

Thanks and regards,

Neeraj Dhekale

[Amanda Hsieh]

Hi, 

You said you are using nRF52840DK, but the project in the figure is blinky_pca10040_s132 which cannot run on nRF52840DK. I would suggest you use nRF52832DK for blinky_pca10040_s132 or use the projects for pca10056 (nRF52840DK)

According to the figure, seems it needs the following:

1. Adding source files

Including header files

2. Adding configurations for NRF_LOG_BACKEND_RTT and nRF_Segger_RTT to sdk_config.h

// </h> 
//==========================================================

// </h> 
//==========================================================

// <h> nRF_Log 

//==========================================================
// <e> NRF_LOG_BACKEND_RTT_ENABLED - nrf_log_backend_rtt - Log RTT backend
//==========================================================
#ifndef NRF_LOG_BACKEND_RTT_ENABLED
#define NRF_LOG_BACKEND_RTT_ENABLED 1
#endif
// <o> NRF_LOG_BACKEND_RTT_TEMP_BUFFER_SIZE - Size of buffer for partially processed strings. 
// <i> Size of the buffer is a trade-off between RAM usage and processing.
// <i> if buffer is smaller then strings will often be fragmented.
// <i> It is recommended to use size which will fit typical log and only the
// <i> longer one will be fragmented.

#ifndef NRF_LOG_BACKEND_RTT_TEMP_BUFFER_SIZE
#define NRF_LOG_BACKEND_RTT_TEMP_BUFFER_SIZE 64
#endif

// <o> NRF_LOG_BACKEND_RTT_TX_RETRY_DELAY_MS - Period before retrying writing to RTT 
#ifndef NRF_LOG_BACKEND_RTT_TX_RETRY_DELAY_MS
#define NRF_LOG_BACKEND_RTT_TX_RETRY_DELAY_MS 1
#endif

// <o> NRF_LOG_BACKEND_RTT_TX_RETRY_CNT - Writing to RTT retries. 
// <i> If RTT fails to accept any new data after retries
// <i> module assumes that host is not active and on next
// <i> request it will perform only one write attempt.
// <i> On successful writing, module assumes that host is active
// <i> and scheme with retry is applied again.

#ifndef NRF_LOG_BACKEND_RTT_TX_RETRY_CNT
#define NRF_LOG_BACKEND_RTT_TX_RETRY_CNT 3
#endif


// </h> 

//==========================================================

// <h> nRF_Segger_RTT 

//==========================================================
// <h> segger_rtt - SEGGER RTT

//==========================================================
// <o> SEGGER_RTT_CONFIG_BUFFER_SIZE_UP - Size of upstream buffer. 
// <i> Note that either @ref NRF_LOG_BACKEND_RTT_OUTPUT_BUFFER_SIZE
// <i> or this value is actually used. It depends on which one is bigger.

#ifndef SEGGER_RTT_CONFIG_BUFFER_SIZE_UP
#define SEGGER_RTT_CONFIG_BUFFER_SIZE_UP 512
#endif

// <o> SEGGER_RTT_CONFIG_MAX_NUM_UP_BUFFERS - Maximum number of upstream buffers. 
#ifndef SEGGER_RTT_CONFIG_MAX_NUM_UP_BUFFERS
#define SEGGER_RTT_CONFIG_MAX_NUM_UP_BUFFERS 2
#endif

// <o> SEGGER_RTT_CONFIG_BUFFER_SIZE_DOWN - Size of downstream buffer. 
#ifndef SEGGER_RTT_CONFIG_BUFFER_SIZE_DOWN
#define SEGGER_RTT_CONFIG_BUFFER_SIZE_DOWN 16
#endif

// <o> SEGGER_RTT_CONFIG_MAX_NUM_DOWN_BUFFERS - Maximum number of downstream buffers. 
#ifndef SEGGER_RTT_CONFIG_MAX_NUM_DOWN_BUFFERS
#define SEGGER_RTT_CONFIG_MAX_NUM_DOWN_BUFFERS 2
#endif

// <o> SEGGER_RTT_CONFIG_DEFAULT_MODE  - RTT behavior if the buffer is full.
 

// <i> The following modes are supported:
// <i> - SKIP  - Do not block, output nothing.
// <i> - TRIM  - Do not block, output as much as fits.
// <i> - BLOCK - Wait until there is space in the buffer.
// <0=> SKIP 
// <1=> TRIM 
// <2=> BLOCK_IF_FIFO_FULL 

#ifndef SEGGER_RTT_CONFIG_DEFAULT_MODE
#define SEGGER_RTT_CONFIG_DEFAULT_MODE 0
#endif

3. main

int main(void)
{


  log_init();

  NRF_LOG_INFO(" Hello ");

     while (true)
    {
        NRF_LOG_FLUSH();
        __SEV();
        __WFE();
        __WFE();
        // no implementation needed
    }

}

Then, you could get the log. 

Test file: blinky_284808.7z, place it under nRF5_SDK_17.1.0_ddde560\examples\peripheral 

Regards,
Amanda

[Neeraj Dhekale]

Thank you so much Amanda Hsieh

Thanks for your help. I was trying to do this from last 2 days . Appreciated.

Just one more addition. I need to enable NRF_LOG_ENABLED as well in sdk_config.h file to make this work.

Thanks and regards,

Neeraj Dhekale