GPIO Interface

Interface Overview

The GPIO (General Purpose Input/Output) interface provides flexible digital I/O expansion. It supports input and output modes and can connect sensors, buttons, indicators, relays, and other external devices. Software can detect device status and control peripherals, giving the system rich hardware interaction for robot control, smart terminals, and embedded applications.

Case Objective

Capture button press events through GPIO.

Required Hardware

• RDK X5 development board
• Female-to-female jumper wires
• GPIO button module

Hardware Connection

Pin Mapping

Note

The mapping between button module pins and board pins is shown below. Board pin numbers follow the BOARD numbering in the 40-pin header definition.

Button module pin	Board pin	Function
OUT	11	Level output
VCC	1	Power
GND	39	Ground

40-Pin Header Definition

Sample Code

Create a gpio_button.py file and paste the following code:

#!/usr/bin/env python3
import sys
import signal
import Hobot.GPIO as GPIO
import time

def signal_handler(signal, frame):
    sys.exit(0)

# Use GPIO pin 11
input_pin = 11 
GPIO.setwarnings(False)

def main():
    prev_value = None

    # Use BOARD physical pin numbering
    GPIO.setmode(GPIO.BOARD)
    # Set the pin as an input
    GPIO.setup(input_pin, GPIO.IN)

    # Wait for a button press (the GPIO button module outputs a low level when pressed)
    GPIO.wait_for_edge(input_pin, GPIO.FALLING)
    print("Starting demo now! Press CTRL+C to exit")
    GPIO.cleanup()

if __name__=='__main__':
    signal.signal(signal.SIGINT, signal_handler)
    main()

Run the Sample

Run the sample with the following command:

python3 gpio_button.py

After you press the button, the program prints “Starting demo now! Press CTRL+C to exit”. Press Ctrl+C to exit.