UART

Hardware interface

ROC-RK3588S-PC The following figure shows the serial port of the
hardware version：


DTS config

File path "kernel-5.10/arch/arm64/boot/dts/rockchip/roc-rk3588s-
pc.dtsi"

   /* uart7 */
   &uart7{
       pinctrl-0 = <&uart7m2_xfer>;
       status = "okay";
   };

After the serial port is configured, the node corresponding to the
hardware interface

   UART7:   /dev/ttyS7

UART send and receive

The easiest way to do this is to stub the UART7 TX RX pin and then use
the command to execute the command in the debug serial port or ADB

   busybox  stty -echo -F /dev/ttyS7          # Close the echo
   cat /dev/ttyS7 &                           # Get /dev/ttyS7 
   echo "firefly uart test..." > /dev/ttyS7   # Input string

The final debugging serial port terminal can receive the string
"firefly uart test..."