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// Example 02: Turn on LED while the button is pressed
//
// Copy and paste this example into an empty Arduino sketch

#define LED 13   // the pin for the LED
#define BUTTON 7 // the input pin where the
                // pushbutton is connected
int val = 0;     // val will be used to store the state
                // of the input pin

void setup() {
 pinMode(LED, OUTPUT);   // tell Arduino LED is an output
 pinMode(BUTTON, INPUT); // and BUTTON is an input
}

void loop(){
 val = digitalRead(BUTTON); // read input value and store it

 // check whether the input is HIGH (button pressed)
 if (val == HIGH) {
   digitalWrite(LED, HIGH); // turn LED ON
 } else {
   digitalWrite(LED, LOW);
 }
}