The LuckFox Pico has three serial ports: UART2, UART3, and UART4. Among them, UART2 is the debug port.

The LuckFox Pico Plus has four serial ports: UART2, UART3, UART4, and UART5. Among them, UART2 is the debug port.

】Performing serial port testing using the GPIO sysfs interface：

(The following operations need to be performed in the terminal of the Pico development board.)

1] View serial port：

root@linaro-alip:/home/linaro# ls /dev/ttyS*

/dev/ttyS3 /dev/ttyS4

##The serial port devices here are UART3 and UART4

2] Use the “stty” tool to query the serial port communication parameters：

linaro@linaro-alip:~$ stty -F /dev/ttyS3

speed 9600 baud; line = 0;

-brkint -imaxbel

##The default baud rate is 9600

3] Modify the baud rate, where ispeed is the input rate and ospeed is the output rate：

stty -F /dev/ttyS3 ispeed 115200 ospeed 115200

4] Disable echo：

stty -F /dev/ttyS3 -echo

## Disabling echo refers to the situation where the characters entered in the terminal or serial communication are no longer displayed on the terminal.

5] Operation process screenshot:

】Communicating with a Windows host：

Connect one end of the serial port module to the computer, and the other end to the physical pins 18 (GND), 19 (UART7_TX), and 20 (UART7_RX) of the LuckFox Pico.

Download and open PuTTY (or any other serial port software), select the serial port, and set the baud rate (default is 9600, please adjust it according to your actual modified value).

Execute the following command on the terminal of the development board to write the strings “Hello” and “world!” to the terminal device file using the echo command:

echo Hello > /dev/ttyS3

echo "world !" > /dev/ttyS3

The serial port debugging assistant on Windows will receive the content:

】Test the built-in sample program of the official SDK：

1] Download SDK&Compiling test example code or download Compiled example code.:

SDK GitHub Download

2] Transfer the test example code file to the development board.

(The following operations need to be performed in the terminal of the Pico development board)

3] Run the test sample program:

chmod 777 ./luckfox_uart_test

## Grant executable permissions to the file

./luckfox_uart_test 3

##The parameter 3 in the example represents UART3.

4] Open the serial communication device to receive data:

TAG： Raspberry Pi CM5 Compute Module 5 Development Kit With CM5104032 + Official Original IO Board + Case Rasperry Pico 2 RP2350 7.3 inch e-Paper Ink Display E6 Full Color Electronic PhotoPainter 800x480 For Calendar/Quotes/Paintings/Posters USB to I2C Pi5 Case Raspberry Pi Display Raspberry Pi 4 USB Audio Raspberry Pi 12.3 inch DSI MIPI Display TouchScreen LCD 720x1920 Luckfox Lyra Omni3576 RK3576 Raspberry Pi LCD TTL To CAN Mini JETSON NANO MINI JETSON NANO JETSON NANO MINI Arduino IR Thermal Imaging Camera E-Ink DeepSeek AI Voice Chat ESP32 S3 Development Board 1.85 inch Round LCD 1.85inch Display QMI8658 /MIC /SD /MP3 Audio LVGL For Arduino USB TO TTL Mini FT232 UART Communication Converter Original FT232RNL RV1103 X1002 Raspberry Pi 5 PCIe to M.2 NVMe SSD Adapter Board HAT Pi5 2280 Raspberry Pi PICO Keyboard Raspberry Pi

Luckfox Pico RV1103【Tutorial on how to use UART】

【First-level Agency】LuckFox Pico Linux RV1103 Rockchip AI Board ARM better than Raspberry Pi Pico

Luckfox Pico RV1103【Tutorial on how to use UART﻿】

【First-level Agency】LuckFox Pico Linux RV1103 Rockchip AI Board ARM better than Raspberry Pi Pico

Luckfox Pico RV1103【Tutorial on how to use UART】