//------------------------------------------------------------------------------------------------------------------------------------------
// Modification by: Alfredo Rainho Neves
// This is an updated version that will actually responde a few thousand times
// a second.
// The CPU load will show very high, but the routine actualy yield 
// giving other tasks a chance. In a multicore CPU only one core will have
// a 100% CPU usage
static DWORD WINAPI prvSimulatedPeripheralTimer( LPVOID lpParameter )
{
	LARGE_INTEGER lpFrequency;
	LARGE_INTEGER startTime;
	LARGE_INTEGER currentTime;
	unsigned long  countPerTick;
	unsigned long  elapsed;

	/* Just to prevent compiler warnings. */
	( void ) lpParameter;

	// Get the performance counter frequency
	QueryPerformanceFrequency(&lpFrequency);

	// Calculate the count per ticks
	countPerTick = lpFrequency.LowPart / configTICK_RATE_HZ;

	while(1)  {
		// Get the start time
		QueryPerformanceCounter(&startTime);

		// Wait for time period to elapse
		do {
			// Yield to another task to make the system more responsive
			Sleep(0);

			// Get the current time
			QueryPerformanceCounter(&currentTime);

			// Calculate the elpased time
			elapsed = currentTime.LowPart - startTime.LowPart; 

		} while (elapsed < countPerTick);

	
		WaitForSingleObject( pvInterruptEventMutex, INFINITE );

		/* The timer has expired, generate the simulated tick event. */
		ulPendingInterrupts |= ( 1 << portINTERRUPT_TICK );

		/* The interrupt is now pending - notify the simulated interrupt 
		handler thread. */
		SetEvent( pvInterruptEvent );

		/* Give back the mutex so the simulated interrupt handler unblocks 
		and can	access the interrupt handler variables. */
		ReleaseMutex( pvInterruptEventMutex );
	}

	#ifdef __GNUC__
		/* Should never reach here - MingW complains if you leave this line out,
		MSVC complains if you put it in. */
		return 0;
	#endif
}