'__log_level' undeclared (first use in this function)

[Ellison]

I want to add log function in one, but compile this display undefined.

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

[Henry_Chou]

CONFIG_LOG_BACKEND_UART=n

because you have to chose RTT or UART for log.

[Ellison]

Thank you for your reply.

I'm adding this, I'm using LOG_INF() for printing, but still compile will report this problem

[Ellison]

[Marte Myrvold]

Hi,

Have you included the log.h file and registered the logging module with

#include <logging/log.h>
LOG_MODULE_REGISTER(foo, CONFIG_FOO_LOG_LEVEL);

Please check out this page about how to use logging in Zephyr.

Best regards,

Marte