/*

The program polls a digital pin to see if the button has been pushed, it outputs
either a 0 or 1 every 40 ns. This demostrates the importance of de-bouncing
a switch as it can register multiple unintended presses.

*/

// digital pin 2 has a pushbutton attached to it. Give it a name:
int pushButton = 2;

// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
  // make the pushbutton's pin an input:
  pinMode(pushButton, INPUT);
}

// the loop routine runs over and over again forever:
void loop() {
  // read the input pin:
  int buttonState = digitalRead(pushButton);
  // print out the state of the button:
  Serial.println(buttonState);
  delay(40);  // delay in between reads for stability
}