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# 9.1 Button

## Hardware Wiring

![Button](/files/-LCFEW-kKEAJj8pAcK39)

## Sketch

The code can be found at [Examples\_Arduino - sensor-kit-for-arduino - \_004\_Button - \_004\_Button.ino](https://github.com/LongerVisionRobot/Examples_Arduino/blob/master/sensor-kit-for-arduino/_004_Button/_004_Button.ino).

```
int Led=13;       // Define LDE Pin
int buttonpin=3;  // Define the button/switch's pin
int val;          // Define Variable val
void setup()
{
  pinMode(Led,OUTPUT);  // Define LED as output
  pinMode(buttonpin,INPUT); // Define button/switch as input
}
void loop()
{
  val=digitalRead(buttonpin); // Assign digital pin's reading to val
  if(val==HIGH)   // if button pressed, LED starts flashing
  {
    digitalWrite(Led,HIGH);
  }
  else
  {
    digitalWrite(Led,LOW);
  }
}
```


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