SimpleKeyboard for Arduino Leonardo

simplekeyboard-example

/* 
 Keyboard Button test
 
 Sends a text string when a button is pressed.
 
 The circuit:
 * pushbutton attached from pin 2 to +5V
 * 10-kilohm resistor attached from pin 4 to ground
 
 created 24 Oct 2011
 modified 27 Mar 2012
 by Tom Igoe
 modified by john schimmel 2012-08-04
 
 This example code is in the public domain.
 
 http://www.arduino.cc/en/Tutorial/KeyboardButton
 */

const int buttonPin = 13;          // input pin for pushbutton
int previousButtonState = LOW;   // for checking the state of a pushButton
int counter = 0;                  // button push counter

void setup() {
  // make the pushButton pin an input:
  pinMode(buttonPin, INPUT);
  // initialize control over the keyboard:
  Keyboard.begin();
}

void loop() {

  // read the pushbutton:
  int buttonState = digitalRead(buttonPin);

  // if the button state has changed, 
  if ((buttonState != previousButtonState) && (buttonState == LOW)) {
    // type out a message
    Keyboard.print("A");
  }

  // save the current button state for comparison next time:
  previousButtonState = buttonState; 
}