public void OpenStream(string ip_address, int start_step, int end_step)
{
const int port_number = 10940;
_start_step = start_step;
_end_step = end_step;
_urg = new TcpClient();
_urg.SendBufferSize = 0;
_urg.ReceiveBufferSize = 0;
_urg.Connect(ip_address, port_number);
_stream = _urg.GetStream();
write(_stream, SCIP_Writer.PP());
readSpec(read_line(_stream));
write(_stream, SCIP_Writer.SCIP2());
read_line(_stream); // ignore echo back
write(_stream, SCIP_Writer.MD(_start_step, _end_step));
read_line(_stream); // ignore echo back
_lockobj = new object();
_read_data = new List <long>();
_distance = new long[_amax + 1];
_calib_distance = new long[_amax + 1]; // store calibration data
_filtered_distance = new long[_amax + 1];
_objs = new List <Vector4>();
_isRun = true;
_thread = new Thread(new ThreadStart(getDataWork));
_thread.Start();
}