void loop(){
      readCommand(computerSerial);
      if (commandSent){
        if(!driverSerial.isListening()){
          driverSerial.listen();
        }
        command = "";
      }
    }

    void readCommand(Stream &source) {
      commandSent = false;
      while (source.available() > 0) {
        char c = source.read();
        if ( (c != '\0') && (c != 10) && (c != 13)){ // if char is not a null or a LF or a CR
          command += c;
        }
        if  (c == 13)  { //if there is a \n then command is sent
          //command += "\r";
          commandSent = true;
          source.print("command:"); //debug
          source.print(command); //debug
          source.println("END"); //debug
          source.flush();
        }
      }
    }