Console no longer receives characters

Sometimes the console no longer receives characters. It can prevent from stopping the boot sequence. If it happens, please follow this procedure:

• Power off the board
• Disable all boot media (put or remove jumpers, no SD card, etc.)
• Power on the board
• Connect to the console
• Reset the board of few times to see the RomBOOT message several times
• Enable the boot media needed
• Reset the board
• You should be able to send characters to the console