code: func (p *SerialPort) Open() (err error) {
  	p.client = NewClientAdaptor(p.address)
  
  	err = p.client.Connect()
  
  	// subscribe to response notifications
  	p.client.Subscribe(p.rid, func(data []byte, e error) {
  		p.responseMutex.Lock()
  		p.responseData = append(p.responseData, data...)
  		p.responseMutex.Unlock()
  	})
  	return
  }
docs: // Open opens a connection to a BLE serial device