Arduino Leonardo keyboard

Fuentes:
https://www.arduino.cc/en/Tutorial/KeyboardMessage
https://www.arduino.cc/en/Tutorial/Debounce




const int buttonPin = 4;  
int ledState = HIGH;      
int buttonState;          
int lastButtonState = LOW;

long lastDebounceTime = 0;
long debounceDelay = 50;  

void setup() {
  pinMode(buttonPin, INPUT);
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, ledState);
}

void loop() {
  int reading = digitalRead(buttonPin);

  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  }
 
  if ((millis() - lastDebounceTime) > debounceDelay) {
    if (reading != buttonState) {
      buttonState = reading;
     
      if (buttonState == HIGH) {
        ledState = !ledState;
      }
    }
  }
 
  if (ledState == HIGH)
  {
    Keyboard.print("1");
    ledState = LOW;
  }
 
  lastButtonState = reading;
}