code: func (b *BlinkMDriver) FirmwareVersion() (version string, err error) {
  	if _, err = b.connection.Write([]byte("Z")); err != nil {
  		return
  	}
  	data := []byte{0, 0}
  	read, err := b.connection.Read(data)
  	if read != 2 || err != nil {
  		return
  	}
  	return fmt.Sprintf("%v.%v", data[0], data[1]), nil
  }
docs: // FirmwareVersion returns version with MAYOR.minor format