#define POINT 100
#define TIRET 300

void setup() {
  Serial.begin(9600);
  pinMode(13, OUTPUT);
  pinMode(2, INPUT_PULLUP);
}

void loop() {
  int etatInterrupteur = digitalRead(2);
  if (etatInterrupteur == LOW) {
    while (digitalRead(2) == LOW) {
      EcrireLettre('S');
      delay(100);
      EcrireLettre('O');
      delay(100);
      EcrireLettre('S');
      delay(300);
    }
  }
}

void EcrireLettre(unsigned char lettre) {
  if (lettre == 'S') {
    digitalWrite(13, HIGH);
    delay(POINT);
    digitalWrite(13, LOW);
    delay(POINT);
    digitalWrite(13, HIGH);
    delay(POINT);
    digitalWrite(13, LOW);
    delay(POINT);
    digitalWrite(13, HIGH);
    delay(POINT);
    digitalWrite(13, LOW);
  }
  else if (lettre == 'O') {
    digitalWrite(13, HIGH);
    delay(TIRET);
    digitalWrite(13, LOW);
    delay(POINT);
    digitalWrite(13, HIGH);
    delay(TIRET);
    digitalWrite(13, LOW);
    delay(POINT);
    digitalWrite(13, HIGH);
    delay(TIRET);
    digitalWrite(13, LOW);
  }
}