> For the complete documentation index, see [llms.txt](https://longer-vision-robot.gitbook.io/arduino-full-stack/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://longer-vision-robot.gitbook.io/arduino-full-stack/09_switches/004_button.md).

# 9.1 Button

## Hardware Wiring

![Button](https://2341898987-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LCFDbcteyTR3tQSs-5x%2F-LCFE4dCRQBMq1ajywfh%2F-LCFEW-kKEAJj8pAcK39%2F004_button.jpg?generation=1526059636870514\&alt=media)

## 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);
  }
}
```