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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
Returnsint
Updated on April 30, 2017 02:33:20pm EDT

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