MissionPlanner.MAVLinkInterface.getWPCount C# (CSharp) Method

        public ushort getWPCount()
        {
            giveComport = true;
            MAVLinkMessage buffer;
            mavlink_mission_request_list_t req = new mavlink_mission_request_list_t();

            req.target_system = MAV.sysid;
            req.target_component = MAV.compid;

            // request list
            generatePacket((byte) MAVLINK_MSG_ID.MISSION_REQUEST_LIST, req);

            DateTime start = DateTime.Now;
            int retrys = 6;

            while (true)
            {
                if (!(start.AddMilliseconds(700) > DateTime.Now))
                {
                    if (retrys > 0)
                    {
                        log.Info("getWPCount Retry " + retrys + " - giv com " + giveComport);
                        generatePacket((byte) MAVLINK_MSG_ID.MISSION_REQUEST_LIST, req);
                        start = DateTime.Now;
                        retrys--;
                        continue;
                    }
                    giveComport = false;
                    //return (byte)int.Parse(param["WP_TOTAL"].ToString());
                    throw new TimeoutException("Timeout on read - getWPCount");
                }

                buffer = readPacket();
                if (buffer.Length > 5)
                {
                    if (buffer.msgid == (byte) MAVLINK_MSG_ID.MISSION_COUNT)
                    {
                        var count = buffer.ToStructure<mavlink_mission_count_t>();


                        log.Info("wpcount: " + count.count);
                        giveComport = false;
                        return count.count; // should be ushort, but apm has limited wp count < byte
                    }
                }
            }
        }