Doubt about the Serial port Arduino

Official Hardware Mega Due
15

Well in the case that you use 2 loops(), one loop that contain delay(), one that take care of the serial port, like loop1 and loop3 in the multiblink example, then you don't really need the serialEvent() any more, since loop3 empty your serial buffer when data come in.

Example, this guy is stuck in the delay()

// Task no.1: blink LED with 1 second delay.
void loop() {
  digitalWrite(led1, HIGH);

  // IMPORTANT:
  // When multiple tasks are running 'delay' passes control to
  // other tasks while waiting and guarantees they get executed.
  delay(1000);

  digitalWrite(led1, LOW);
  delay(1000);
}

Mean while, this guy empty the buffer:

// Task no.3: accept commands from Serial port
// '0' turns off LED
// '1' turns on LED
void loop3() {
  if (Serial.available()) {
    char c = Serial.read();
    if (c=='0') {
      digitalWrite(led3, LOW);
      Serial.println("Led turned off!");
    }
    if (c=='1') {
      digitalWrite(led3, HIGH);
      Serial.println("Led turned on!");
    }
  }

  // IMPORTANT:
  // We must call 'yield' at a regular basis to pass
  // control to other tasks.
  yield();
}

And both actions are done simultaneously.