Please tell me how to use px4iofirmware/mixer.cpp debug message (isr_debug)!

Pixhawk
1

I want to know how to see the px4iofirmware/mixer.cpp debug message.

I have used Mavlink Console in QGroundControl v3.5.6 and write “px4io debug 1”.
But, no debug message has returned in Mavlink Console.

Please tell me how to use px4iofirmware/mixer.cpp debug message (isr_debug)!!

mavlink_console|473x500