/*
 LightToggleDebounced
 Toggle an LED on and off (with s/w debouncing)
 */

const int pushButtonPin = 2;    // connect the push button to digital pin 2
const int ledPin = 13;          // connect the LED to pin 13
const int debounceTime = 5;     // number of millisecods to delay after button press

boolean ledState = LOW;         // used to set LED
boolean lastButtonState = HIGH; // value of buttonState from previous loop iteration
boolean buttonState = HIGH;

boolean debounce(int pinNum) {
  delay(debounceTime);
  return digitalRead(pinNum);
}

void setup() {
  pinMode(pushButtonPin, INPUT);      // make the pushbutton's pin an input
  digitalWrite(pushButtonPin, HIGH);  // turn on pullup resistors
  pinMode(ledPin, OUTPUT);            // make LED's pin an output
  digitalWrite(ledPin, ledState);
}

void loop() {
  buttonState = debounce(pushButtonPin);  // read the input pin

  // if button goes down and previously it was high...
  if (buttonState == LOW && lastButtonState == HIGH) {
    ledState = !ledState;
  }

  lastButtonState = buttonState;
  digitalWrite(ledPin, ledState);  // turn the LED on or off
}