pisca-pisca em 2 tempos

#define pino 5

unsigned long millis1000, millis300;
bool tag1000;
byte tagKey;

void setup() {

  pinMode(pino, OUTPUT);
  millis1000 = millis();
}

void loop() {

  if ((millis() - millis1000 >= 1000) && (tag1000 == 0)) {
    tag1000 = 1;
    tagKey = 0;
    millis300 = millis();
  }

  if (tag1000 == 1) {
    if (millis() - millis300 >= 300) {
      switch (tagKey) {
        case 0:
          digitalWrite (pino, HIGH);
          break;
        case 1:
          digitalWrite (pino, LOW);
          break;
        case 2:
          digitalWrite (pino, HIGH);
          break;
        case 3:
          digitalWrite (pino, LOW);
          tag1000 = 0;
          millis1000 = millis();
          break;
      }
      tagKey++;
      millis300 = millis();
    }
  }
}