private void InitPorts()
        {
            List <string> ports = PortControl.GetParallelPorts();

            if (ports != null)
            {
                cboxPorts.Items.Clear();
                foreach (string p in ports)
                {
                    cboxPorts.Items.Add(p);
                }
                cboxPorts.SelectedIndex = 0;
            }
        }