private void PopulateListView(string filterName = null)
        {
            SymbolListViewItems?.Clear();
            if (_plcConnections.Count == 0)
            {
                return;
            }

            foreach (ISymbol symbol in _plcConnections[_activePlc].Symbols)
            {
                if (filterName == null || symbol.InstancePath.ToLower().Contains(filterName.ToLower()))
                {
                    SymbolListViewItems?.Add(new SymbolInfo
                    {
                        Path         = symbol.InstancePath,
                        Type         = symbol.TypeName,
                        Size         = symbol.Size,
                        IndexGroup   = ((IAdsSymbol)symbol).IndexGroup,
                        IndexOffset  = ((IAdsSymbol)symbol).IndexOffset,
                        IsStatic     = symbol.IsStatic,
                        CurrentValue = "pending..." // GetSymbolValue(symbol) // startup takes to long with loads of variables
                    });
                }
            }
        }
        private void ConnectPlc()
        {
            _activePlc   = 0;
            _activePorts = GetActivePlcPorts("127.0.0.1.1.1", 851);
            _plcConnections.Clear();
            ComboBoxPlc.Items.Clear();
            SymbolListViewItems?.Clear();
            foreach (int port in _activePorts)
            {
                PlcConnection plcCon = new PlcConnection(new AmsAddress($"127.0.0.1.1.1:{port}"));
                plcCon.PlcConnectionError += PlcOnPlcConnectionError;
                plcCon.Connect();
                if (plcCon.Connected)
                {
                    plcCon.Connection.AdsStateChanged        += PlcAdsStateChanged;
                    plcCon.Connection.ConnectionStateChanged += PlcOnConnectionStateChanged;
                    plcCon.Connection.AmsRouterNotification  += PlcOnAmsRouterNotification;
                }
                _plcConnections.Add(plcCon);
            }

            if (_plcConnections.Count == 0)
            {
                UpdateDumpStatus("No active PLCs found", Colors.Orange);
                return;
            }

            if (_plcConnections[_activePlc].Connected)
            {
                UpdateDumpStatus("Retrieving symbols", Colors.GreenYellow);
                PopulateListView();
            }

            // Populate Combobox
            if (_plcConnections.Count > 0)
            {
                foreach (int activePort in _activePorts)
                {
                    ComboBoxItem cbi = new ComboBoxItem();
                    cbi.Content = activePort.ToString();
                    ComboBoxPlc.Items.Add(cbi);
                }

                ComboBoxPlc.SelectedIndex = 0;
            }

            PlcConnected             = _plcConnections[_activePlc].Connected;
            ButtonDumpData.IsEnabled = PlcConnected;
        }