def start
      @stop = false
      @reader_thread = Thread.new {
        begin
          message = @port.gets(@separator)
          changed
          notify_observers(message)
        end while (@stop == false)
      }
    end
def start
      @stop = false
      @reader_thread = Thread.new {
        begin
          message = @port.gets(@separator)
          changed
          notify_observers(message)
        end while (@stop == false)
      }
    end
Begin processing incoming data from the serial port.
 A thread is started which monitors the port for data and detects
 complete messages.
 Call TextProtocol#stop to halt this process.