Demo/Common/Minimal/TimerDemo.c

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*/


/*
 * Tests the behaviour of timers.  Some timers are created before hte scheudler
 * is started, and some after.
 */

/* Standard includes. */
#include <string.h>

/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
#include "timers.h"

/* Demo program include files. */
#include "TimerDemo.h"

#if configTIMER_TASK_PRIORITY < 1
	#error configTIMER_TASK_PRIORITY must be set to at least 1 for this test/demo to function correctly.
#endif

#define tmrdemoDONT_BLOCK				( ( portTickType ) 0 )
#define tmrdemoONE_SHOT_TIMER_PERIOD	( xBasePeriod * ( portTickType ) 3 )
#define trmdemoNUM_TIMER_RESETS			( ( unsigned char ) 10 )

/*-----------------------------------------------------------*/

static void prvAutoReloadTimerCallback( xTimerHandle pxExpiredTimer );
static void prvTimerControlTask( void *pvParameters );

static void prvTest1_CreateTimersWithoutSchedulerRunning( void );
static void	prvTest3_CheckAutoReloadExpireRates( void );
static void prvTest2_CheckTaskAndTimersInitialState( void );
static void prvTest4_CheckAutoReloadTimersCanBeStopped( void );
static void prvTest5_CheckBasicOneShotTimerBehaviour( void );
static void prvTest6_CheckAutoReloadResetBehaviour( void );
static void prvResetStartConditionsForNextIteration( void );

/*-----------------------------------------------------------*/

/* Flag that will be latched to pdFAIL should any unexpected behaviour be
detected in any of the demo tests. */
static volatile portBASE_TYPE xTestStatus = pdPASS;

/* Counter that is incremented on each cycle of a test.  This is used to
detect a stalled task - a test that is no longer running. */
static volatile unsigned portLONG ulLoopCounter = 0;

static xTimerHandle xAutoReloadTimers[ configTIMER_QUEUE_LENGTH + 1 ] = { 0 };
static unsigned char ucAutoReloadTimerCounters[ configTIMER_QUEUE_LENGTH + 1 ] = { 0 };
static unsigned char ucOneShotTimerCounter = ( unsigned char ) 0;

static xTimerHandle xOneShotTimer = NULL;

static portTickType xBasePeriod = 0;

/*-----------------------------------------------------------*/

void vStartTimerDemoTask( portTickType xBasePeriodIn )
{
	/* Store the period from which all the timer periods will be generated from
	(multiples of). */
	xBasePeriod = xBasePeriodIn;

	/* Create a set of timers for use by this demo/test. */
	prvTest1_CreateTimersWithoutSchedulerRunning();

	/* Create the task that will control and monitor the timers.  This is
	created at a lower priority than the timer service task to ensure, as
	far as it is concerned, commands on timers are actioned immediately
	(sending a command to the timer service task will unblock the timer service
	task, which will then preempt this task). */
	if( xTestStatus != pdFAIL )
	{
		xTaskCreate( prvTimerControlTask, ( signed portCHAR * ) "Tmr Ctl", configMINIMAL_STACK_SIZE, NULL, configTIMER_TASK_PRIORITY - 1, NULL );
	}
}
/*-----------------------------------------------------------*/

static void prvAutoReloadTimerCallback( xTimerHandle pxExpiredTimer )
{
portBASE_TYPE xTimerID;

	xTimerID = ( portBASE_TYPE ) pvTimerGetTimerID( pxExpiredTimer );
	if( xTimerID <= ( configTIMER_QUEUE_LENGTH + 1 ) )
	{
		( ucAutoReloadTimerCounters[ xTimerID ] )++;
	}
	else
	{
		/* The timer ID appears to be unexpected (invalid). */
		xTestStatus = pdFAIL;
	}
}
/*-----------------------------------------------------------*/

static void prvOneShotTimerCallback( xTimerHandle pxExpiredTimer )
{
	/* The parameter is not used in this case as only one timer uses this
	callback function. */
	( void ) pxExpiredTimer;

	ucOneShotTimerCounter++;
}
/*-----------------------------------------------------------*/

static void prvTimerControlTask( void *pvParameters )
{
	( void ) pvParameters;

	/* Create a one-shot timer for use later on in this test. */
	xOneShotTimer = xTimerCreate(	"Oneshot Timer",				/* Text name to facilitate debugging.  The kernel does not use this itself. */
									tmrdemoONE_SHOT_TIMER_PERIOD,/* The period for the timer. */
									pdFALSE,						/* Don't autoreload - hence a one shot timer. */
									( void * ) 0,					/* The timer identifier.  In this case this is not used as the timer has its own callback. */
									prvOneShotTimerCallback );		/* The callback to be called when the timer expires. */

	if( xOneShotTimer == NULL )
	{
		xTestStatus = pdFAIL;
	}


	/* Ensure all the timers are in their expected initial state.  This
	depends on the timer service task having a higher priority than this task. */
	prvTest2_CheckTaskAndTimersInitialState();

	for( ;; )
	{
		/* Check the auto reload timers expire at the expected/correct rates. */
		prvTest3_CheckAutoReloadExpireRates();

		/* Check the auto reload timers can be stopped correctly, and correctly
		report their state. */
		prvTest4_CheckAutoReloadTimersCanBeStopped();
				
		/* Check the one shot timer only calls its callback once after it has been 
		started, and that it reports its state correctly. */
		prvTest5_CheckBasicOneShotTimerBehaviour();

		/* Check timer reset behaviour. */
		prvTest6_CheckAutoReloadResetBehaviour();

		/* Start the timers again to restart all the tests over again. */
		prvResetStartConditionsForNextIteration();
	}
}
/*-----------------------------------------------------------*/

/* This is called to check that the created task is still running and has not
detected any errors. */
portBASE_TYPE xAreTimerDemoTasksStillRunning( void )
{
static unsigned portLONG ulLastLoopCounter = 0;

	/* If the demo task is still running then we expect the loopcounter to
	have incremented since this function was last called. */
	if( ulLastLoopCounter == ulLoopCounter )
	{
		xTestStatus = pdFAIL;
	}

	ulLastLoopCounter = ulLoopCounter;

	/* Errors detected in the task itself will have latched xTestStatus
	to pdFAIL. */

	return xTestStatus;
}
/*-----------------------------------------------------------*/

static void prvTest1_CreateTimersWithoutSchedulerRunning( void )
{
portBASE_TYPE xTimer;

	for( xTimer = 0; xTimer < configTIMER_QUEUE_LENGTH; xTimer++ )
	{
		/* As the timer queue is not yet full, it should be possible to both create
		and start a timer.  These timers are being started before the scheduler has
		been started, so their block times should get set to zero within the timer
		API itself. */
		xAutoReloadTimers[ xTimer ] = xTimerCreate( "FR Timer",						/* Text name to facilitate debugging.  The kernel does not use this itself. */
													( ( xTimer + 1 ) * xBasePeriod ),/* The period for the timer.  The plus 1 ensures a period of zero is not specified. */
													pdTRUE,								/* Autoreload is set to true. */
													( void * ) xTimer,					/* An identifier for the timer as all the auto reload timers use the same callback. */
													prvAutoReloadTimerCallback );		/* The callback to be called when the timer expires. */

		if( xAutoReloadTimers[ xTimer ] == NULL )
		{
			xTestStatus = pdFAIL;
		}
		else
		{
			/* The scheduler has not yet started, so the block period of
			portMAX_DELAY should just get set to zero in xTimerStart().  Also,
			the timer queue is not yet full so xTimerStart() should return
			pdPASS. */
			if( xTimerStart( xAutoReloadTimers[ xTimer ], portMAX_DELAY ) != pdPASS )
			{
				xTestStatus = pdFAIL;
			}
		}
	}

	/* The timers queue should now be full, so it should be possible to create
	another timer, but not possible to start it (the timer queue will not get
	drained until the scheduler has been started. */
	xAutoReloadTimers[ configTIMER_QUEUE_LENGTH ] = xTimerCreate( "FR Timer",		/* Text name to facilitate debugging.  The kernel does not use this itself. */
													( configTIMER_QUEUE_LENGTH * xBasePeriod ),	/* The period for the timer. */
													pdTRUE,							/* Autoreload is set to true. */
													( void * ) xTimer,				/* An identifier for the timer as all the auto reload timers use the same callback. */
													prvAutoReloadTimerCallback );	/* The callback to be called when the timer expires. */

	if( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH ] == NULL )
	{
		xTestStatus = pdFAIL;
	}
	else
	{
		if( xTimerStart( xAutoReloadTimers[ xTimer ], portMAX_DELAY ) == pdPASS )
		{
			/* This time it would not be expected that the timer could be
			started at this point. */
			xTestStatus = pdFAIL;
		}
	}
}
/*-----------------------------------------------------------*/

static void prvTest2_CheckTaskAndTimersInitialState( void )
{
unsigned char ucTimer;

	/* Ensure all the timers are in their expected initial state.  This	depends 
	on the timer service task having a higher priority than this task.

	auto reload timers 0 to ( configTIMER_QUEUE_LENGTH - 1 ) should now be active,
	and auto reload timer configTIMER_QUEUE_LENGTH should not yet be active (it 
	could not be started prior to the scheduler being started when it was 
	created). */
	for( ucTimer = 0; ucTimer < ( unsigned char ) configTIMER_QUEUE_LENGTH; ucTimer++ )
	{
		if( xTimerIsTimerActive( xAutoReloadTimers[ ucTimer ] ) == pdFALSE )
		{
			xTestStatus = pdFAIL;
		}
	}

	if( xTimerIsTimerActive( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH ] ) != pdFALSE )
	{
		xTestStatus = pdFAIL;
	}
}
/*-----------------------------------------------------------*/

static void	prvTest3_CheckAutoReloadExpireRates( void )
{
unsigned char ucMaxAllowableValue, ucMinAllowableValue, ucTimer;
portTickType xNextWakeTime;

	/* Check the auto reload timers expire at the expcted rates. */

	/* Initialise the next wake time value before the call to vTaskDelayUntil() 
	as this is not really a periodic task. */
	xNextWakeTime = xTaskGetTickCount();

	/* Delaying for configTIMER_QUEUE_LENGTH * xBasePeriod ticks should allow 
	all the auto reload timers to expire at least once. */
	vTaskDelayUntil( &xNextWakeTime, ( ( portTickType ) configTIMER_QUEUE_LENGTH ) * xBasePeriod );

	/* Check that all the auto reload timers have called their callback	
	function the expected number of times. */
	for( ucTimer = 0; ucTimer < ( unsigned char ) configTIMER_QUEUE_LENGTH; ucTimer++ )
	{
		/* The timer in array position 0 should elapse every xBasePeriod ticks, 
		the timer in array position 1 should elapse every ( 2 * xBasePeriod ) 
		ticks, etc.  This task blocked for configTIMER_QUEUE_LENGTH * xBasePeriod, 
		so the timer in array position 0 should have elapsed 
		configTIMER_QUEUE_LENGTH times, the	timer in array possition 1 should 
		have elapsed ( configTIMER_QUEUE_LENGTH - 1 ) times, etc. */
		ucMaxAllowableValue = ( ( ( unsigned char ) configTIMER_QUEUE_LENGTH ) - ucTimer );
		ucMinAllowableValue = ( ( ( unsigned char ) configTIMER_QUEUE_LENGTH ) - ucTimer ) - 1;

		if( ( ucAutoReloadTimerCounters[ ucTimer ] < ucMinAllowableValue ) ||
			( ucAutoReloadTimerCounters[ ucTimer ] > ucMaxAllowableValue )
			)
		{
			xTestStatus = pdFAIL;
		}
	}

	if( xTestStatus == pdPASS )
	{
		/* No errors have been reported so increment the loop counter so the 
		check task knows this task is still running. */
		ulLoopCounter++;
	}
}
/*-----------------------------------------------------------*/

static void prvTest4_CheckAutoReloadTimersCanBeStopped( void )
{		
unsigned char ucTimer;

	/* Check the auto reload timers can be stopped correctly, and correctly 
	report their state. */

	/* Stop all the active timers. */
	for( ucTimer = 0; ucTimer < ( unsigned char ) configTIMER_QUEUE_LENGTH; ucTimer++ )
	{
		/* The timer has not been stopped yet! */
		if( xTimerIsTimerActive( xAutoReloadTimers[ ucTimer ] ) == pdFALSE )
		{
			xTestStatus = pdFAIL;
		}

		/* Now stop the timer.  This will appear to happen immediately to
		this task because this task is running at a priority below the
		timer service task. */
		xTimerStop( xAutoReloadTimers[ ucTimer ], tmrdemoDONT_BLOCK );

		/* The timer should now be inactive. */
		if( xTimerIsTimerActive( xAutoReloadTimers[ ucTimer ] ) != pdFALSE )
		{
			xTestStatus = pdFAIL;
		}
	}

	taskENTER_CRITICAL();
	{
		/* The timer in array position configTIMER_QUEUE_LENGTH should not
		be active.  The critical section is used to ensure the timer does
		not call its callback between the next line running and the array
		being cleared back to zero, as that would mask an error condition. */
		if( ucAutoReloadTimerCounters[ configTIMER_QUEUE_LENGTH ] != ( unsigned char ) 0 )
		{
			xTestStatus = pdFAIL;
		}

		/* Clear the timer callback count. */
		memset( ( void * ) ucAutoReloadTimerCounters, 0, sizeof( ucAutoReloadTimerCounters ) );
	}
	taskEXIT_CRITICAL();

	/* The timers are now all inactive, so this time, after delaying, none
	of the callback counters should have incremented. */
	vTaskDelay( ( ( portTickType ) configTIMER_QUEUE_LENGTH ) * xBasePeriod );
	for( ucTimer = 0; ucTimer < ( unsigned char ) configTIMER_QUEUE_LENGTH; ucTimer++ )
	{
		if( ucAutoReloadTimerCounters[ ucTimer ] != ( unsigned char ) 0 )
		{
			xTestStatus = pdFAIL;
		}
	}

	if( xTestStatus == pdPASS )
	{
		/* No errors have been reported so increment the loop counter so
		the check task knows this task is still running. */
		ulLoopCounter++;
	}
}
/*-----------------------------------------------------------*/

static void prvTest5_CheckBasicOneShotTimerBehaviour( void )
{
	/* Check the one shot timer only calls its callback once after it has been 
	started, and that it reports its state correctly. */

	/* The one shot timer should not be active yet. */
	if( xTimerIsTimerActive( xOneShotTimer ) != pdFALSE )
	{
		xTestStatus = pdFAIL;
	}

	if( ucOneShotTimerCounter != ( unsigned char ) 0 )
	{
		xTestStatus = pdFAIL;
	}

	/* Start the one shot timer and check that it reports its state correctly. */
	xTimerStart( xOneShotTimer, tmrdemoDONT_BLOCK );
	if( xTimerIsTimerActive( xOneShotTimer ) == pdFALSE )
	{
		xTestStatus = pdFAIL;
	}

	/* Delay for three times as long as the one shot timer period, then check 
	to ensure it has only called its callback once, and is now not in the 
	active state. */
	vTaskDelay( tmrdemoONE_SHOT_TIMER_PERIOD * ( portTickType ) 3 );

	if( xTimerIsTimerActive( xOneShotTimer ) != pdFALSE )
	{
		xTestStatus = pdFAIL;
	}

	if( ucOneShotTimerCounter != ( unsigned char ) 1 )
	{
		xTestStatus = pdFAIL;
	}
	else
	{
		/* Reset the one shot timer callback count. */
		ucOneShotTimerCounter = ( unsigned char ) 0;
	}

	if( xTestStatus == pdPASS )
	{
		/* No errors have been reported so increment the loop counter so the 
		check task knows this task is still running. */
		ulLoopCounter++;
	}
}
/*-----------------------------------------------------------*/

static void prvTest6_CheckAutoReloadResetBehaviour( void )
{
unsigned char ucTimer;

	/* Check timer reset behaviour. */

	/* Restart the one shot timer and check it reports its status correctly. */
	xTimerStart( xOneShotTimer, tmrdemoDONT_BLOCK );
	if( xTimerIsTimerActive( xOneShotTimer ) == pdFALSE )
	{
		xTestStatus = pdFAIL;
	}

	/* Restart one of the auto reload timers and check that it reports its
	status correctly. */
	xTimerStart( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH - 1 ], tmrdemoDONT_BLOCK );
	if( xTimerIsTimerActive( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH - 1 ] ) == pdFALSE )
	{
		xTestStatus = pdFAIL;
	}

	for( ucTimer = 0; ucTimer < trmdemoNUM_TIMER_RESETS; ucTimer++ )
	{
		/* Delay for half as long as the one shot timer period, then reset it.  
		It should never expire while this is done, so its callback count should 
		never increment. */
		vTaskDelay( tmrdemoONE_SHOT_TIMER_PERIOD / 2 );

		/* Check both running timers are still active, but have not called their
		callback functions. */
		if( xTimerIsTimerActive( xOneShotTimer ) == pdFALSE )
		{
			xTestStatus = pdFAIL;
		}

		if( ucOneShotTimerCounter != ( unsigned char ) 0 )
		{
			xTestStatus = pdFAIL;
		}

		if( xTimerIsTimerActive( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH - 1 ] ) == pdFALSE )
		{
			xTestStatus = pdFAIL;
		}

		if( ucAutoReloadTimerCounters[ configTIMER_QUEUE_LENGTH - 1 ] != ( unsigned char ) 0 )
		{
			xTestStatus = pdFAIL;
		}

		/* Reset both running timers. */
		xTimerReset( xOneShotTimer, tmrdemoDONT_BLOCK );
		xTimerReset( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH - 1 ], tmrdemoDONT_BLOCK );

		if( xTestStatus == pdPASS )
		{
			/* No errors have been reported so increment the loop counter so 
			the check task knows this task is still running. */
			ulLoopCounter++;
		}
	}

	/* Finally delay long enough for both running timers to expire. */
	vTaskDelay( ( ( portTickType ) configTIMER_QUEUE_LENGTH ) * xBasePeriod );

	/* The timers were not reset during the above delay period so should now
	both have called their callback functions. */
	if( ucOneShotTimerCounter != ( unsigned char ) 1 )
	{
		xTestStatus = pdFAIL;
	}

	if( ucAutoReloadTimerCounters[ configTIMER_QUEUE_LENGTH - 1 ] == 0 )
	{
		xTestStatus = pdFAIL;
	}

	/* The one shot timer should no longer be active, while the auto reload
	timer should still be active. */
	if( xTimerIsTimerActive( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH - 1 ] ) == pdFALSE )
	{
		xTestStatus = pdFAIL;
	}

	if( xTimerIsTimerActive( xOneShotTimer ) == pdTRUE )
	{
		xTestStatus = pdFAIL;
	}

	/* Stop the auto reload timer again. */
	xTimerStop( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH - 1 ], tmrdemoDONT_BLOCK );

	if( xTimerIsTimerActive( xAutoReloadTimers[ configTIMER_QUEUE_LENGTH - 1 ] ) != pdFALSE )
	{
		xTestStatus = pdFAIL;
	}

	/* Clear the timer callback counts, ready for another iteration of these
	tests. */
	ucAutoReloadTimerCounters[ configTIMER_QUEUE_LENGTH - 1 ] = ( unsigned char ) 0;
	ucOneShotTimerCounter = ( unsigned char ) 0;

	if( xTestStatus == pdPASS )
	{
		/* No errors have been reported so increment the loop counter so the check 
		task knows this task is still running. */
		ulLoopCounter++;
	}
}
/*-----------------------------------------------------------*/

static void prvResetStartConditionsForNextIteration( void )
{
unsigned char ucTimer;

	/* Start the timers again to start all the tests over again. */

	/* Start the timers again. */
	for( ucTimer = 0; ucTimer < ( unsigned char ) configTIMER_QUEUE_LENGTH; ucTimer++ )
	{
		/* The timer has not been started yet! */
		if( xTimerIsTimerActive( xAutoReloadTimers[ ucTimer ] ) != pdFALSE )
		{
			xTestStatus = pdFAIL;
		}

		/* Now start the timer.  This will appear to happen immediately to
		this task because this task is running at a priority below the timer 
		service task. */
		xTimerStart( xAutoReloadTimers[ ucTimer ], tmrdemoDONT_BLOCK );

		/* The timer should now be active. */
		if( xTimerIsTimerActive( xAutoReloadTimers[ ucTimer ] ) == pdFALSE )
		{
			xTestStatus = pdFAIL;
		}
	}

	if( xTestStatus == pdPASS )
	{
		/* No errors have been reported so increment the loop counter so the 
		check task knows this task is still running. */
		ulLoopCounter++;
	}
}
/*-----------------------------------------------------------*/