int byte_read = 0; ///< The current byte
    bool dataHasBeenReaden = false;
    char s[512] = "";
    int cpt=0;
    void setup() {
      // put your setup code here, to run once:
      Serial.begin(9600);
    }
    
    void loop()  // put your main code here, to run repeatedly:
    {      
      dataHasBeenReaden = false;
      cpt = 0;
      while ( Serial.available() ) 
      {
          dataHasBeenReaden = true;
          byte_read = Serial.read();
          s[cpt] = byte_read;
          cpt++;
          //Serial.print("byte%i:");
      }
      if (dataHasBeenReaden)
      {
        Serial.print("chaine recue et renvoyee:");   
        Serial.println(s);   
      }
      delay(1000);