ATTENTION! Bootloader upgrade is a risky operation and should not be performed unless absolutely necessary! If anything goes wrong during this process (power shortage, mistype, etc.) the board will be BRICKED (broken). Keep in mind that warranty does not cover Kinkan module if it is damaged due to user's fault.
192.168.1.254 IP address on your computer's ethernet interface.
3. Reboot Kinkan and press ESC when prompted to enter <RealTek> bootloader.
(no additional steps required via serial, just keep watching the upgrade status)
4. Transfer realtek binary to the device (execute command from your local computer).
tftp -m binary 192.168.1.6 -c put kinkan_boot_v1.0.bin
5. Wait until process is complete.