Configuring RTT for Nordic thingy 52 connected to nrf5340's debug out

[muditsharmaa]

Hi,

I am current working with nrf connect SDK, nrf5340dk and 2 Nordic thingy 52s. I am trying to implement BLE mesh sensor client and server model on both the Thingys respectively and programming them via the nrf5340dk's debug out. I wish to look at the output of the mesh sensor client via RTT but I'm unable to do so.

I have added the following configuration parameters in the prj.conf file for enabling RTT:

ONFIG_UART_CONSOLE=n
CONFIG_HAS_SEGGER_RTT=y
CONFIG_USE_SEGGER_RTT=y
CONFIG_RTT_CONSOLE=y
CONFIG_LOG_BACKEND_RTT=y
CONFIG_LOG_STRDUP_BUF_COUNT=20
CONFIG_LOG_STRDUP_MAX_STRING=8
CONFIG_LOG_DEFAULT_LEVEL=4

Can someone please help me configure RTT for nordic thingy 52?

Thank you!

[Carl Richard]

Hi!

Could you try to add "CONFIG_LOG=y" as well? I used the following prj.conf to successfully log over RTT via the nRF5340DK OB Debugger:

# Config logger
CONFIG_LOG=y
CONFIG_USE_SEGGER_RTT=y
CONFIG_LOG_BACKEND_RTT=y
CONFIG_LOG_BACKEND_UART=n
CONFIG_RTT_CONSOLE=y

Best regards,
Carl Richard

[muditsharmaa]

Hi Carl,

thanks for the reply.

I also have the following config parameters in the prj.conf file. Still cant see the RTT output.

# General configuration

CONFIG_MAIN_STACK_SIZE=4096

CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=4096

CONFIG_FLASH=y

CONFIG_FLASH_MAP=y

CONFIG_NVS=y

CONFIG_SETTINGS=y

CONFIG_HWINFO=y

CONFIG_ASSERT=y

CONFIG_ASSERT_LEVEL=2

CONFIG_LOG=y

CONFIG_LOG_PRINTK=y

Can you please tell me how did you setup the jlink RTT viewer? Do you need to enable/disable VCOM via the jlink configurator? 

best regards,

Mudit Sharma

[Carl Richard]

Hi again!

I get a build error when trying your prj.conf dure to "CONFIG_HAS_SEGGER_RTT=y". Could you try to remove this, as well as building with a "Clean build folder" (SES) or "pristine" (command line).

Best regards,
Carl Richard

[muditsharmaa]

Hi Carl,

I followed your suggestion and I see output on the RTT viewer but I'm not seeing the printk() messages. 

On the RTT viewer I see the following output:

Can you kindly suggest what could be causing this and how to fix this?

thank you.

[Carl Richard]

Hi again!

I suspect that the printk messages might be suppressed due to excessive logging. Could you try to remove CONFIG_LOG_DEFAULT_LEVEL=4 (so that DBG messages aren't shown) and see if helps? That's currently the only difference between my prj.conf and yours.

Best regards,
Carl Richard

[muditsharmaa]

Hi Carl,

It works perfectly now. Thanks for the help!

[Carl Richard]

Good to hear! Glad I could help.

Best regards,
Carl Richard