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Maxuino/Arduino input control to output control of LED

Here you can make an input with a switch turn on and off an LED. This is the beginning of an interactive action.


Using the Arduino IDE to activate an led with a switch or button



Turns on and off a light emitting diode(LED) connected to digital

pin 13, when pressing a pushbutton attached to pin 2.

The circuit:

* LED attached from pin 13 to ground

* pushbutton attached to pin 2 from +5V

* 10K resistor attached to pin 2 from ground

* Note: on most Arduinos there is already an LED on the board

attached to pin 13.

created 2005

by DojoDave <http://www.0j0.org>

modified 30 Aug 2011

by Tom Igoe

This example code is in the public domain.



// constants won't change. They're used here to

// set pin numbers:

const int buttonPin = 2;     // the number of the pushbutton pin

const int ledPin =  13;      // the number of the LED pin

// variables will change:

int buttonState = 0;         // variable for reading the pushbutton status

void setup() {

// initialize the LED pin as an output:

pinMode(ledPin, OUTPUT);

// initialize the pushbutton pin as an input:

pinMode(buttonPin, INPUT);


void loop() {

// read the state of the pushbutton value:

buttonState = digitalRead(buttonPin);

// check if the pushbutton is pressed.

// if it is, the buttonState is HIGH:

if (buttonState == HIGH) {

// turn LED on:

digitalWrite(ledPin, HIGH);

} else {

// turn LED off:

digitalWrite(ledPin, LOW);