code: func crcCalculate(m *MAVLinkPacket) uint16 {
  	crc := crcInit()
  
  	for _, v := range m.Pack()[1 : m.Length+6] {
  		crc = crcAccumulate(v, crc)
  	}
  	message, _ := m.MAVLinkMessage()
  	crc = crcAccumulate(message.Crc(), crc)
  	return crc
  }
docs: //
  // Calculates the X.25 checksum on a byte buffer
  //
  // return the checksum over the buffer bytes
  //