BLE蓝牙发现设备后不可以连接问题

[qq_25890587]

procedure TForm1.btnFindClick(Sender: TObject);
begin
  if btnfind.Caption = '搜索'  then
  begin
    BluetoothLE1.Enabled := true;
    BluetoothLE1.DiscoverDevices(10000);
    btnfind.Caption := '停止';
  end else
  begin
    bluetoothle1.Enabled := false;
    btnfind.Caption := '搜索';
  end;
end;

procedure TForm1.BitBtn1Click(Sender: TObject);
var
  it: TBluetoothLEDevice;
  itt:  TBluetoothGattServer;
  i,j,n: integer;
begin
  listbox2.Clear;
  //定位listbox1选中的device索引
  j := -1;
  for i := 0 to listbox1.Count do
  begin
    if listbox1.Selected[i] then
    begin
      j := i;
      break;
    end;
  end;
  if j < 0 then
  begin
    tag := -1;
    exit;
  end;

  //停止发现
  BluetoothLE1.CancelDiscovery;

 //获取device对象元素
  it := lst.Items[ strtoint(leftStr(listbox1.Items[j],2))-1];
  //showmessage(inttostr(it.Services.Count)); //显示0个服务
  //连接设备
  if it.Connect  then
    showmessage('connect ok')
  else
    showmessage('connnect fail');

end;

//BLE发现事件
procedure TForm1.BluetoothLE1DiscoverLEDevice(const Sender: TObject;
  const ADevice: TBluetoothLEDevice; Rssi: Integer;
  const ScanResponse: TScanResponse);
var
  n,i: integer;
  it: TBluetoothLEDevice;
  flag: boolean;
begin
  //查找是否地址重复
  flag := true;
  for i := 0 to lst.Count - 1 do
  begin
    it := lst.Items[i];
    if it.Address = aDevice.Address then
    begin
      flag := false;
      break;
    end;
  end;

  //不重复设备加入到lst和listbox1中
  if flag then
  begin
    i := listbox1.Count + 1;
    listbox1.Items.Add(format('%.02d',[i]) + ':' + ADevice.DeviceName + '[' + adevice.Address + ']');
    lst.Add(Adevice)   ;
  end;
end

试了很多次，只能搜索到BLE设备，但调用connect立即返回失败。不调用connect直接获取service会报没有配对的错误.
操作系统WIN10，适配器CSR4.0,