main.c

FreeRTOS的应用范例

		/* Delay until it is time to execute again. */
		vTaskDelay( xDelayPeriod );

		/* Delete the dynamically created task. */
		if( xCreatedTask != mainNO_TASK )
		{
			vTaskDelete( xCreatedTask );
		}

		/* Check all the standard demo application tasks are executing without 
		error.  ulMemCheckTaskRunningCount is checked to ensure it was
		modified by the task just deleted. */
		if( prvCheckOtherTasksAreStillRunning( ulMemCheckTaskRunningCount ) != pdPASS )
		{
			/* An error has been detected in one of the tasks - flash faster. */
			xDelayPeriod = mainERROR_FLASH_PERIOD;
		}

		/* The toggle rate of the LED depends on how long this task delays for.
		An error reduces the delay period and so increases the toggle rate. */
		vParTestToggleLED( mainON_BOARD_LED_BIT );
	}
}
/*-----------------------------------------------------------*/

static void prvSetupHardware( void )
{
portLONG lCount;

	#ifdef RUN_FROM_ROM
	{
	portFLOAT nsecsPerClockTick;
	portLONG lNumWaitStates;
	unsigned portLONG ulCSRWaitValue;

		/* We are compiling to run from ROM (either on-chip or off-chip flash).
		Leave the RAM/flash mapped the way they are on reset
		(flash @ 0x00000000, RAM @ 0x00300000), and set up the
		proper flash wait states (starts out at the maximum number
		of wait states on reset, so we should be able to reduce it).
		Most of this code will probably get removed by the compiler
		if optimization is enabled, since these calculations are
		based on constants.  But the compiler should still produce
		a correct wait state register value. */
		nsecsPerClockTick = ( portFLOAT ) 1000000000 / configCPU_CLOCK_HZ;
		lNumWaitStates = ( portLONG )( ( configFLASH_SPEED_NSEC / nsecsPerClockTick ) + 0.5 ) - 1;

		if( lNumWaitStates < 0 )
		{
			lNumWaitStates = 0;
		}

		if( lNumWaitStates > MAX_WAIT_STATES )
		{
			lNumWaitStates = MAX_WAIT_STATES;
		}

		ulCSRWaitValue = ululCSRWaitValues[ lNumWaitStates ];
		ulCSRWaitValue = WaitState5;

		AT91C_BASE_EBI->EBI_CSR[ 0 ] = ulCSRWaitValue | DataBus16 | WaitStateEnable
									   | PageSize1M | tDF_0cycle 
									   | ByteWriteAccessType | CSEnable
									   | 0x00000000 /* Base Address */;
	}
	#else  /* else we are compiling to run from on-chip RAM */
	{
		/* If compiling to run from RAM, we expect the on-chip RAM to already
		be mapped at 0x00000000.  This is typically done with an initialization
		script for the JTAG emulator you are using to download and run the
		demo application. So there is nothing to do here in this case. */
	}
	#endif

	/* Disable all interrupts at the AIC level initially... */
	AT91C_BASE_AIC->AIC_IDCR = 0xFFFFFFFF;

	/* Set all SVR and SMR entries to default values (start with a clean slate)... */
	for( lCount = 0; lCount < 32; lCount++ )
	{
		AT91C_BASE_AIC->AIC_SVR[ lCount ] = (unsigned long) 0;
		AT91C_BASE_AIC->AIC_SMR[ lCount ] = AIC_SRCTYPE_INT_EDGE_TRIGGERED;
	}

	/* Disable clocks to all peripherals initially... */
	AT91C_BASE_PS->PS_PCDR = 0xFFFFFFFF;

	/* Clear all interrupts at the AIC level initially... */
	AT91C_BASE_AIC->AIC_ICCR = 0xFFFFFFFF;

	/* Perform 8 "End Of Interrupt" cmds to make sure AIC will not Lock out 
	nIRQ */
	for( lCount = 0; lCount < 8; lCount++ )
	{
		AT91C_BASE_AIC->AIC_EOICR = 0;
	}

	/* Initialise LED outputs. */
	vParTestInitialise();
}
/*-----------------------------------------------------------*/

static portLONG prvCheckOtherTasksAreStillRunning( unsigned portLONG ulMemCheckTaskCount )
{
portLONG lReturn = ( portLONG ) pdPASS;

	/* Check all the demo tasks (other than the flash tasks) to ensure
	that they are all still running, and that none of them have detected
	an error. */

	if( xAreIntegerMathsTaskStillRunning() != pdTRUE )
	{
		lReturn = ( portLONG ) pdFAIL;
	}

	if( xAreComTestTasksStillRunning() != pdTRUE )
	{
		lReturn = ( portLONG ) pdFAIL;
	}

	if( xArePollingQueuesStillRunning() != pdTRUE )
	{
		lReturn = ( portLONG ) pdFAIL;
	}

	if( xAreMathsTaskStillRunning() != pdTRUE )
	{
		lReturn = ( portLONG ) pdFAIL;
	}

	if( xAreSemaphoreTasksStillRunning() != pdTRUE )
	{
		lReturn = ( portLONG ) pdFAIL;
	}

	if( xAreDynamicPriorityTasksStillRunning() != pdTRUE )
	{
		lReturn = ( portLONG ) pdFAIL;
	}

	if( xAreBlockingQueuesStillRunning() != pdTRUE )
	{
		lReturn = ( portLONG ) pdFAIL;
	}

	if( ulMemCheckTaskCount == mainCOUNT_INITIAL_VALUE )
	{
		/* The vMemCheckTask did not increment the counter - it must
		have failed. */
		lReturn = ( portLONG ) pdFAIL;
	}

	return lReturn;
}
/*-----------------------------------------------------------*/

static void vMemCheckTask( void *pvParameters )
{
unsigned portLONG *pulMemCheckTaskRunningCounter;
void *pvMem1, *pvMem2, *pvMem3;
static portLONG lErrorOccurred = pdFALSE;

	/* This task is dynamically created then deleted during each cycle of the
	vErrorChecks task to check the operation of the memory allocator.  Each time
	the task is created memory is allocated for the stack and TCB.  Each time
	the task is deleted this memory is returned to the heap.  This task itself
	exercises the allocator by allocating and freeing blocks. 
	
	The task executes at the idle priority so does not require a delay. 
	
	pulMemCheckTaskRunningCounter is incremented each cycle to indicate to the
	vErrorChecks() task that this task is still executing without error. */

	pulMemCheckTaskRunningCounter = ( unsigned portLONG * ) pvParameters;

	for( ;; )
	{
		if( lErrorOccurred == pdFALSE )
		{
			/* We have never seen an error so increment the counter. */
			( *pulMemCheckTaskRunningCounter )++;
		}
		else
		{
			/* There has been an error so reset the counter so the check task 
			can tell that an error occurred. */
			*pulMemCheckTaskRunningCounter = mainCOUNT_INITIAL_VALUE;
		}

		/* Allocate some memory - just to give the allocator some extra 
		exercise.  This has to be in a critical section to ensure the
		task does not get deleted while it has memory allocated. */
		vTaskSuspendAll();
		{
			pvMem1 = pvPortMalloc( mainMEM_CHECK_SIZE_1 );
			if( pvMem1 == NULL )
			{
				lErrorOccurred = pdTRUE;
			}
			else
			{
				memset( pvMem1, 0xaa, mainMEM_CHECK_SIZE_1 );
				vPortFree( pvMem1 );
			}
		}
		xTaskResumeAll();

		/* Again - with a different size block. */
		vTaskSuspendAll();
		{
			pvMem2 = pvPortMalloc( mainMEM_CHECK_SIZE_2 );
			if( pvMem2 == NULL )
			{
				lErrorOccurred = pdTRUE;
			}
			else
			{
				memset( pvMem2, 0xaa, mainMEM_CHECK_SIZE_2 );
				vPortFree( pvMem2 );
			}
		}
		xTaskResumeAll();

		/* Again - with a different size block. */
		vTaskSuspendAll();
		{
			pvMem3 = pvPortMalloc( mainMEM_CHECK_SIZE_3 );
			if( pvMem3 == NULL )
			{
				lErrorOccurred = pdTRUE;
			}
			else
			{
				memset( pvMem3, 0xaa, mainMEM_CHECK_SIZE_3 );
				vPortFree( pvMem3 );
			}
		}
		xTaskResumeAll();
	}
}