procedure TForm1.Timer1Timer(Sender: TObject);
var
  p: TPoint;
begin
  p := Point(Button1.Left + Button1.Width div 2,
             Button1.Top + Button1.Height div 2);
  p := Form1.ClientToScreen(p);
  SetCursorPos(p.x, p.y);
  p := Point(round(p.x * 65535 / Screen.Width),
             round(p.y * 65535 / Screen.Height));
  Mouse_Event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_MOVE,
    p.x, p.y, 0, 0);
  Application.ProcessMessages;
  sleep(100);
  Mouse_Event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTDOWN,
    p.x, p.y, 0, 0);
  Application.ProcessMessages;
  sleep(300);
  Mouse_Event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTUP,
    p.x, p.y, 0, 0);
end;