Reference IStopwatch

  IStopwatch = interface(IInterface)
  public
    { Update the time by querying for an accurate time }
    function Calculate: Double;
    { Reset the timer to zero }
    procedure Reset;
    { Time expired between the last calculate and reset }
    property Time: Double read GetTime;
    { Pauses time calculation }
    property Paused: Boolean read GetPaused write SetPaused;
  end;