Ao.Timing.Win32

The Ao.Timing.Win32 namespace encapsulates timing features of the native Win32 API. In contrast to the other namespaces, its members are implemented in C++/CLI.

Just like the Ao.Timing namespace it utilizes the Time struct defined in the Ao.Measurements namespace.

Tick Counter

The native GetTickCount64() function returns the number of milliseconds that have elapsed since the system was started. The Tick class provides access to this value.

Console.WriteLine(Tick.Now.Seconds);

345343.453

The resolution of this clock is limited to the resolution of the system timer, which defaults to 15.6 milliseconds.

Performance Counter

The native QueryPerformanceCounter() function returns a similar value with a much higher resolution, usually less than a microsecond. The Performance class provides access to this value.

Console.WriteLine(Performance.Now.Seconds);
Console.WriteLine(Performance.Now.Seconds);
Console.WriteLine(Performance.Now.Seconds);

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The class also provides the actual update frequency.

Console.WriteLine("{0} MHz", Performance.Frequency.Megahertz);

10 MHz

Multimedia Timer

The native multimedia timer services are an alternative to the various timer classes of the .NET framework library, for they can fire events at higher resolutions. The static MultimediaTimer class provides a constant for the minimum possible resolution.

Console.WriteLine("{0} ms", MultimediaTimer.MinResolutionMs);

1 ms

As mentioned above, the multimedia timer classes are based on a custom timestamp. The tick counter or the performance counter can be used for this purpose.

Time Timestamp() => Tick.Now;

Time Timestamp() => Performance.Now;

One-Shot Multimedia Timer

The MultimediaTimerOneShot class represents a timer, that fires only once after the specified delay and then stops automatically.

Time OnElapsed(object sender, TimerEventArgs e)
{
    Console.WriteLine(e.Time.Seconds);
}

var T = new MultimediaTimerOneShot(Timestamp);

T.DelayMs = 500;
T.Elapsed += OnElapsed;
T.ResolutionMs = 1;

T.Start(); 

The Resolution property specifies the resolution, however, this is a global value. Windows will always use the minimum resolution currently requested, so starting another timer with a higher resolution will result in that one running at 1 ms resolution, too.

Periodic Multimedia Timer

The MultimediaTimerPeriodic class represents a timer, that fires periodically every time the specified delay has expired. It needs to be stopped manually.

var T = new MultimediaTimerPeriodic(Timestamp);

T.DelayMs = 500;
T.Elapsed += OnElapsed;
T.ResolutionMs = 1;

T.Start(); 

Thread.Sleep(5000);

T.Stop();

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