private void btnOK_Click(object sender, EventArgs e)
        {
            var tempate_str = "{0};{1},{2},{3},{4};{5}";
            var str         = string.Format(tempate_str,
                                            cmbPorts.Text.Substring(3),
                                            cmbBaud.Text,
                                            cmbCheck.SelectedIndex,
                                            cmbDataBit.Text,
                                            cmbStopBit.SelectedIndex,
                                            nudAdd.Value);

            AccessDBHelper.UpdateModel(model);
            this.DialogResult = DialogResult.OK;
        }