Connect to UART Port

Most AIoT evaluation kits and development boards have the UART0 port connected to an UART-to-USB chip, such as FTDI-232 on AIoT-i350-EVK, which expose the UART serial console as an USB serial device to your host PC.

Port Location

For other development boards, you might want to check which port the UART0 is connected to in the user guide or schematics of the board.

Baud Rate and Consoles

The UART0 port allows you access bootloader and kernel console. Note that different baud rates are used for different purposes:

Console Baud Rates

Console

Baud Rate

Purpose

Download Agent

921600

Download progress log from download agent (lk.bin) when using aiot-flash

Boot ROM

115200

SoC boot ROM logs and messages

Bootloader Console

921600

U-Boot console for debugging and boot configurations

Kernel Console

921600

kernel messages and console

Note: UART0 and USB0 can connect to the board simultaneously. UART0 get BROM and kernel console logs. USB0 is used to flash the image to the board.

Settings other than baud rate are the same between bootloader and kernel console:

  • Data Bits: 8

  • Stop Bits: 1

  • Parity: None

  • Flow control: None

Login Identity

Use root to login to the UART kernel console when a login prompt is shown.

Connect to UART on Linux

You can now connect to the UART using the following command:

picocom -b 921600 /dev/ttyUSB0

or using

screen /dev/ttyUSB0 921600

Note

Depending on your system, you may have more than one USB serial device connected, which means the board might not be presented as /dev/ttyUSB0 in your system. In this case, please try other ttyUSB devices (i.e. /dev/ttyUSB1, /dev/ttyUSB2, etc.)

Connect to UART on Windows

After driver installation, you can use serial terminal programs to connect to COM ports, such as: