 
  Turns on and off a light emitting diode(LED) connected to digital
  pin 13, when pressing a key attached to pin 2.
-
- This is 
-
 
  The circuit:
  * LED built in to pin 13, connected to ground

  // Compare them - state records inverse of switch read
  if (value == state) { // Equal means a change
    // Update values as needed, if needed
    value = not state;
    digitalWrite(ledPin, value);
  }
}


 by Tom Igoe
 modified 03 May 2016
 by @JDWarner
*/

// constants won't change. They're used here to
// set pin numbers:
const int keyPin = 2;          // pin from organ key
const int ledPin = LED_BUILTIN;  // LED pin
bool keyState = false;    // the key state, starts off
bool keyRead = false;     // input from digital pin

