- Processing
- p5.js
- Processing.py
- Processing for Android

- Processing Foundation

This reference is for Processing 3.0+. If you have a previous version, use the reference included with your software in the Help menu. If you see any errors or have suggestions, please let us know. If you prefer a more technical reference, visit the Processing Core Javadoc and Libraries Javadoc.

Class | GPIO
Name | ### digitalRead()
Examples |
    import processing.io.*;

    void setup() {
      GPIO.pinMode(4, GPIO.INPUT);

      // On the Raspberry Pi, GPIO 4 is pin 7 on the pin header,
      // located on the fourth row, above one of the ground pins

      frameRate(0.5);
    }

    void draw() {
      // sense the input pin
      if (GPIO.digitalRead(4) == GPIO.HIGH) {
        fill(255);
      } else {
        fill(204);
      }
      stroke(255);
      ellipse(width/2, height/2, width*0.75, height*0.75);
    }
Description | Returns the value of an input pin, which is either GPIO.HIGH (1) or GPIO.LOW (0) You need to set the pin to input by calling pinMode() before calling this function.
Syntax |
    .digitalRead(pin)
Parameters |
pin | int: GPIO pin
Returns | int

Updated on November 10, 2017 05:36:31pm EST