How To Use Uart

Confirm serial port hardware pins

Uart pin in 40 pins header is pin15 and pin16

Open uart node

openg uart node via device tree overlays.

$ vim /boot/env.txt

Make sure UART is in the overlays list (default is enable).

overlays=uart4 pwm_ao_a pwm_f i2c0

note: VIM1/VIM2 is uar4,VIM3/VIM3L is uart3

Setting serial tool in PC

Connect you board’s uart and you PC via ttytoUSB tool.

The baud rate is set to 115200, here is Ubuntu as an example:

$ sudo minicom -b 115200 -D /dev/ttyUSBx

How to Use

Open the terminal on the board and set the serial port baud rate.

$ sudo stty -F /dev/ttySx 115200

Print info via echo command

$ echo khadas | sudo tee /dev/ttySx

You will receive khadas in you PC