code: func NewDriver(a *Adaptor, config string, v ...time.Duration) *Driver {
  	d := &Driver{
  		name:       gobot.DefaultName("Joystick"),
  		connection: a,
  		Eventer:    gobot.NewEventer(),
  		configPath: config,
  		poll: func() sdl.Event {
  			return sdl.PollEvent()
  		},
  		interval: 10 * time.Millisecond,
  		halt:     make(chan bool, 0),
  	}
  
  	if len(v) > 0 {
  		d.interval = v[0]
  	}
  
  	d.AddEvent("error")
  	return d
  }
docs: // NewDriver returns a new Driver with a polling interval of
  // 10 Milliseconds given a Joystick Adaptor and json button configuration
  // file location.
  //
  // Optionally accepts:
  //  time.Duration: Interval at which the Driver is polled for new information