Week 9a Digital Input and Output

const int ledPin = 2;
const int buttonPin = 3;
unsigned long timer = 0;
bool onOff = LOW;
byte prevButtonState = LOW;
bool blinking = false;

void setup() {
  // put your setup code here, to run once:
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  // read the button pin
  // store that in a local variable
  byte buttonState  = digitalRead(buttonPin);

  // print out the state of the button stored in the variable
  Serial.println(buttonState);

  // check to see if the button is pressed and last time it wasn't
  // only do something if that is the case
  if (buttonState == HIGH && prevButtonState == LOW) {
    // change blinking to not blinking
    blinking = !blinking;
  }

  // record the current button state for use next time through loop
  prevButtonState = buttonState;

  // if blinkkng is true, do the blinking stuff
  if (blinking == true) {
    // check to see if the current time (millis) is greater than the timer we recorded
    if (millis() > timer) {
      // flip the boolean
      onOff = !onOff;
      // record a new time to check against
      timer = millis() + 250;
      // turn the led on and off
      digitalWrite(ledPin, onOff);
    }
    / otherwise turn the LED off
  } else {
    digitalWrite(ledPin, LOW);
  }
}