/* Turn Signal
 This simple program simulates a car's turn signal using two LEDS and a double throw switch
 with a center off position. When the switch is thrown to the left, the LED embedded in the
 left side of an object will blink until the switch is returned to the center position.
 
 This code adapts the "Blink without delay" code, found under File>Sketchbook>Examples>Digital
 
 */

int ledPinL= 3;                // Pin for Left LED
int ledPinR = 2;               // Pin for Right LED
int inputPinL = 1;             // Input pin for when switch is activated to the left
int inputPinR = 0;             // Input pin for when switch is activated to the right
int valL = 0;                  // variable for reading the pin status
int valR = 0;                  // variable for reading the pin status
long timer = 0;                // variable to store last time an LED was updated
long interval = 300;           // blinking interval (milliseconds)

int onoff = LOW;
void setup() {
  pinMode(ledPinL, OUTPUT);      // declare Left LED as output
  pinMode(inputPinL, INPUT);     // declare right side of switch as input 
  //(directions are reversed here since flipping the switch
  // to the left connects the switch's center pin to the right pin 
  pinMode(ledPinR, OUTPUT);      // declare Right LED as output
  pinMode(inputPinR, INPUT);     // declare left side of switch as input
}

void loop(){

  valL = digitalRead(inputPinL);    // read input value
  if (valL == HIGH) {               // check if the input is HIGH
    digitalWrite(ledPinL, LOW);     // Turn LED off
  }
  else{
    if(millis() - timer > interval){ // check to see if LED should blink
      timer = millis();
      if(onoff == LOW) // if LED is on, turn it off, and vice versa
        onoff = HIGH;
      else
        onoff = LOW;
      digitalWrite(ledPinL, onoff);  
    }
  }   
  valR = digitalRead(inputPinR);   // read input value
  if (valR == HIGH) {                 // check if the input is HIGH
    digitalWrite(ledPinR, LOW);       // Turn LED off
  }
  else{
    if(millis() - timer > interval){ // check to see if LED should blink
      timer = millis();
      if(onoff == LOW) // if LED is on, turn it off, and vice versa
        onoff = HIGH;
      else
        onoff = LOW;
      digitalWrite(ledPinR, onoff);  
    }
  }     

}