Arduino

Reference Language | Libraries | Comparison | Changes

## boolean

A boolean holds one of two values, true or false. (Each boolean variable occupies one byte of memory.)

#### Example

    int LEDpin = 5;       // LED on pin 5
    int switchPin = 13;   // momentary switch on 13, other side connected to ground

    boolean running = false;

    void setup()
    {
      pinMode(LEDpin, OUTPUT);
      pinMode(switchPin, INPUT);
      digitalWrite(switchPin, HIGH);      // turn on pullup resistor
    }

    void loop()
    {
      if (digitalRead(switchPin) == LOW)
      {  // switch is pressed - pullup keeps pin high normally
        delay(100);                        // delay to debounce switch
        running = !running;                // toggle running variable
        digitalWrite(LEDpin, running)      // indicate via LED
      }
    }

#### See also

- constants
- boolean operators
- Variable Declaration

Reference Home

Corrections, suggestions, and new documentation should be posted to the Forum.

The text of the Arduino reference is licensed under a Creative Commons Attribution-ShareAlike 3.0 License. Code samples in the reference are released into the public domain.

### Share

### This link has expired.
Please re-subscribe to our Newsletters.

### Subscribe to our Newsletters

Email

Please enter a valid email to subscribe

Arduino Newsletter
Arduino Store Newsletter

### Confirm your email address

We need to confirm your email address.
To complete the subscription, please click the link in the email we just sent you.

Thank you for subscribing!

Arduino
via Egeo 16
Torino, 10131
Italy

###### Newsletter

- ©2015 Arduino
- Copyright Notice
- Contact us
- Careers