millis LED 2 second example

unsigned long previousMillis = 0;
unsigned long stoptime = 2000;
unsigned long currentMillis = millis();


int led = 13;
int ledstate = LOW;

boolean timerOn = false;  // know when to check for the timer
boolean toogleLED = true;  // set a flag so the switch only happens once

void setup(){
  Serial.begin(9600); // Debug will be disabled in final versions
  pinMode(led, OUTPUT);
  digitalWrite(led, LOW);
  delay(5000);
  Serial.println("...Program start\n");
}

void loop() {
  currentMillis = millis();  // get current time

  digitalWrite(led, ledstate);  // always update the pin

  if((currentMillis - previousMillis >= stoptime) && (timerOn == true)) {
    // we hit the interval time, stoptime
    Serial.println("Timer has expired, Turning off LED");
    ledstate = LOW;
    timerOn = false;
  }

  if ((ledstate == LOW) && (toogleLED == true)) {
    Serial.println("Turning on LED, Lets see if it turns off in 2 seconds");
    ledstate = HIGH;
    previousMillis = currentMillis;  // store CURRENT time to compare against
    toogleLED = false;
    timerOn = true;
  }
}