Install TFTP software on the PC and connect R4 LAN to the computer network port.Then change your computer’s configuration based on the Settings, writing the updated filename without pressing Enter
Configure the IP address in Network & Internet settings.
Open TFTP software on the PC, set the transfer file path and the ip of the PC.
R4 board serial port debugging to confirm the transfer of BL2 file.
After successfully upgrading the BL2 file, restart the device.