blink senza delay()

Una cosa del genere può andare?

const int ledPin =  13;      // the number of the LED pin

// Variables will change:
int ledState = LOW;             // ledState used to set the LED
long previousMillis = 0;        // will store last time LED was updated

// the follow variables is a long because the time, measured in miliseconds,
// will quickly become a bigger number than can be stored in an int.
long interval = 6000;           // interval at which to blink (milliseconds)

void setup() {
  // set the digital pin as output:
  pinMode(ledPin, OUTPUT);      
  Serial.begin(57600);
}

void loop()
{
  // here is where you'd put code that needs to be running all the time.

  // check to see if it's time to blink the LED; that is, if the
  // difference between the current time and last time you blinked
  // the LED is bigger than the interval at which you want to
  // blink the LED.
  unsigned long currentMillis = millis();
  Serial.write(currentMillis - previousMillis + "\n");
  if(currentMillis - previousMillis > interval ) {
    // save the last time you blinked the LED
    previousMillis = currentMillis;
    interval=3000;

    // if the LED is off turn it on and vice-versa:
    if (ledState == LOW){
      ledState = HIGH;
    }
    else
      ledState = LOW;
  }
  else{
    if (previousMillis==0)
      ledState = HIGH;
  }
  // set the LED with the ledState of the variable:
  digitalWrite(ledPin, ledState);

}

A me sembra che funzioni.