40 Pin GPIO 接口

瑞莎 Dragon Q8B 板载 40-Pin GPIO（通用输入输出）接口，为硬件扩展提供了高度灵活的接口支持。

用户可以通过 40-Pin GPIO 接口连接各类传感器、执行器、通信模块、显示屏以及其他嵌入式外设，从而快速实现物联网（IoT）、机器人控制、工业自动化等领域的原型开发与功能验证。

危险

使用 40-Pin GPIO 接口时，请注意引脚和外设的接线，请确保引脚连接正确，不当操作可能导致设备硬件损坏。

GPIO 功能

Dragon Q8B 支持通过板载 GPIO 引脚连接外部设备，并支持 UART、SPI、I2C 等多种复用功能。

Function4	Function3	Function2	Function1	Function0	Pin#	Pin#	Function0	Function1	Function2	Function3
				3V3	1	2	5V
	SPI9_MISO	UART9_CTS	I2C9_SDA	GPIO_41	3	4	5V
	SPI9_MOSI	UART9_RFR	I2C9_SCL	GPIO_42	5	6	GND
			SPI4_CS_3	GPIO_175	7	8	GPIO_63	UART17_TX
				GND	9	10	GPIO_64	UART17_RX
	SPI4_CS_1		I2C5_SDA	GPIO_111	11	12	GPIO_174	UART4_RX	SPI4_CS_0
HS-UART18_CTS	SPI18_MISO	UART18_CTS	I2C18_SDA	GPIO_66	13	14	GND
HS-UART18_RFR	SPI18_MOSI	UART18_RFR	I2C18_SCL	GPIO_67	15	16	GPIO_68	UART18_TX	SPI18_SCKL	HS-UART18_TX
				3.3V	17	18	GPIO_110
	SPI20_MOSI	UART20_RFR	I2C20_SCL	GPIO_88	19	20	GND
	SPI20_MISO	UART20_CTS	I2C20_SDA	GPIO_87	21	22	GPIO_92	SPI20_CS_2
		SPI20_SCKL	UART20_TX	GPIO_89	23	24	GPIO_90	UART20_RX	SPI20_CS_0
				GND	25	26	GPIO_91	SPI20_CS_1
	SPI9_SCKL	UART9_TX	I2C8_SDA	GPIO_43	27	28	GPIO_44	I2C8_SCL	UART9_RX	SPI9_CS_0
		SPI6_CS_0	UART6_RX	GPIO_157	29	30	GND
		SPI6_SCKL	UART6_TX	GPIO_156	31	32	GPIO_114	CCI_I2C_SCL0	GCC_GP2_CLK_MIRA
		GCC_GP3_CLK_MRIA	CCI_I2C_SDA1	GPIO_115	33	34	GND
	SPI4_MISO	UART4_CTS	I2C4_SDA	GPIO_171	35	36	GPIO_112	I2C5_SCL	SPI4_CS_2
	HS-UART18_RX	SPI18_CS_0	UART18_RX	GPIO_69	37	38	GPIO_172	I2C4_SCL	UART4_RFR	SPI4_MOSI
				GND	39	40	GPIO_173	UART4_TX	SPI4_SCKL

GPIO 使用

通过板载的 40-Pin GPIO 接口，演示常见的 GPIO 使用方法。

安装 Python 库

使用 python-periphery 库控制 GPIO 引脚。

radxa@dragon-q8b$

sudo apt update
sudo apt install -y python3-periphery

GPIO 输出/输入

硬件准备

主板
杜邦线

软件准备

python-periphery 库

测试代码

以下代码是使用 python-periphery 库来控制 GPIO_42 引脚输出高低电平，然后通过 GPIO_175 引脚读取 GPIO_42 引脚的高低电平。

gpio_output_input.py

from periphery import GPIO
import time

def gpio_output_with_feedback():
    # GPIO Configuration (modify pin numbers based on your hardware)
    # GPIO_42 (output)  → maps to line 42 of /dev/gpiochip4
    # GPIO_175 (input)  → maps to line 175 of /dev/gpiochip4
    OUTPUT_PIN_CHIP = "/dev/gpiochip4"
    OUTPUT_PIN_NUMBER = 42    # GPIO_42 (output pin, controlled by the script)
    INPUT_PIN_NUMBER = 175    # GPIO_175 (input pin, reads GPIO_42's output state)

    # Initialize GPIO objects as None first (for safe release later)
    gpio_out = None
    gpio_in = None

    try:
        # Initialize GPIO_42 as OUTPUT mode
        gpio_out = GPIO(OUTPUT_PIN_CHIP, OUTPUT_PIN_NUMBER, "out")
        # Initialize GPIO_175 as INPUT mode
        gpio_in = GPIO(OUTPUT_PIN_CHIP, INPUT_PIN_NUMBER, "in")

        # Print test initialization info
        print("=== GPIO Output-Input Feedback Test Started ===")
        print(f"Controlled Pin (GPIO_42): {OUTPUT_PIN_CHIP} - Line {OUTPUT_PIN_NUMBER} (OUTPUT)")
        print(f"Monitoring Pin (GPIO_175): {OUTPUT_PIN_CHIP} - Line {INPUT_PIN_NUMBER} (INPUT)")
        print("Test Behavior: GPIO_42 toggles HIGH/LOW every 1s; GPIO_175 verifies GPIO_42's state")
        print("Press Ctrl+C to stop the test\n")

        # Main loop: Toggle GPIO_42 and read GPIO_175 feedback
        while True:
            # 1. Set GPIO_42 to HIGH level
            gpio_out.write(True)
            time.sleep(0.1)  # Short delay for signal stabilization (avoid read lag)
            gpio175_reading = gpio_in.read()
            print(f"GPIO_42 Output: HIGH (True) | GPIO_175 Reading: {gpio175_reading}")

            # Keep GPIO_42 HIGH for 1 second
            time.sleep(1)

            # 2. Set GPIO_42 to LOW level
            gpio_out.write(False)
            time.sleep(0.1)  # Short delay for signal stabilization
            gpio175_reading = gpio_in.read()
            print(f"GPIO_42 Output: LOW (False) | GPIO_175 Reading: {gpio175_reading}")

            # Keep GPIO_42 LOW for 1 second
            time.sleep(1)

    # Handle user-initiated exit (Ctrl+C)
    except KeyboardInterrupt:
        print("\n\nTest stopped by user (Ctrl+C)")
    # Handle other unexpected errors (e.g., GPIO access failure)
    except Exception as e:
        print(f"\nError during test: {str(e)}")
    # Ensure GPIO resources are released even if an error occurs
    finally:
        print("\nReleasing GPIO resources...")
        # Safely close GPIO_42 (set to LOW first to avoid residual high level)
        if gpio_out:
            try:
                gpio_out.write(False)
                gpio_out.close()
                print(f"Successfully closed GPIO_42 (Line {OUTPUT_PIN_NUMBER})")
            except Exception as close_err:
                print(f"Failed to close GPIO_42 (Line {OUTPUT_PIN_NUMBER}): {str(close_err)}")
        # Safely close GPIO_175
        if gpio_in:
            try:
                gpio_in.close()
                print(f"Successfully closed GPIO_175 (Line {INPUT_PIN_NUMBER})")
            except Exception as close_err:
                print(f"Failed to close GPIO_175 (Line {INPUT_PIN_NUMBER}): {str(close_err)}")
        print("Resource release complete.")

# Run the test when the script is executed directly
if __name__ == "__main__":
    gpio_output_with_feedback()

测试步骤

将 GPIO_42 引脚和 GPIO_175 引脚进行短接（分别为 40-Pin 排针的第 5 脚和第 7 脚）
将代码保存为 gpio_output_input.py
使用 sudo python3 gpio_output_input.py 命令运行测试代码

实验现象

终端会输出 GPIO_42 输出的电平和 GPIO_175 读取的电平信息。

False 代表低电平，True 代表高电平。

GPIO 功能​

GPIO 使用​

安装 Python 库​

GPIO 输出/输入​

硬件准备​

软件准备​

测试代码​

测试步骤​

实验现象​