Using defmt for logging

[romancardenas]

Hi all!

Is it possible to set defmt for logging with a hifive1 board? So far I've been using the UART, but I suspect the serial port is interfering with GDB and the debugging experience with cortex-debug is poor.

[almindor]

I've haven't used defmt with riscv board yet.

I generally just use gdb for running/debugging and serial-monitor on the /dev/ttyACMx for the log output.

As for code I just use the sprintln! macro from the hifive1 crate.