text: /*
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      ***************************************************************************
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      ***************************************************************************
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  */
  
  #ifndef EVENT_GROUPS_H
  #define EVENT_GROUPS_H
  
  #ifndef INC_FREERTOS_H
  	#error "include FreeRTOS.h" must appear in source files before "include event_groups.h"
  #endif
  
  #include "timers.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**
   * An event group is a collection of bits to which an application can assign a
   * meaning.  For example, an application may create an event group to convey
   * the status of various CAN bus related events in which bit 0 might mean "A CAN
   * message has been received and is ready for processing", bit 1 might mean "The
   * application has queued a message that is ready for sending onto the CAN
   * network", and bit 2 might mean "It is time to send a SYNC message onto the
   * CAN network" etc.  A task can then test the bit values to see which events
   * are active, and optionally enter the Blocked state to wait for a specified
   * bit or a group of specified bits to be active.  To continue the CAN bus
   * example, a CAN controlling task can enter the Blocked state (and therefore
   * not consume any processing time) until either bit 0, bit 1 or bit 2 are
   * active, at which time the bit that was actually active would inform the task
   * which action it had to take (process a received message, send a message, or
   * send a SYNC).
   *
   * The event groups implementation contains intelligence to avoid race
   * conditions that would otherwise occur were an application to use a simple
   * variable for the same purpose.  This is particularly important with respect
   * to when a bit within an event group is to be cleared, and when bits have to
   * be set and then tested atomically - as is the case where event groups are
   * used to create a synchronisation point between multiple tasks (a
   * 'rendezvous').
   *
   * \defgroup EventGroup
   */
  
  
  
  /**
   * event_groups.h
   *
   * Type by which event groups are referenced.  For example, a call to
   * xEventGroupCreate() returns an EventGroupHandle_t variable that can then
   * be used as a parameter to other event group functions.
   *
   * \defgroup EventGroupHandle_t EventGroupHandle_t
   * \ingroup EventGroup
   */
  typedef void * EventGroupHandle_t;
  
  /*
   * The type that holds event bits always matches TickType_t - therefore the
   * number of bits it holds is set by configUSE_16_BIT_TICKS (16 bits if set to 1,
   * 32 bits if set to 0.
   *
   * \defgroup EventBits_t EventBits_t
   * \ingroup EventGroup
   */
  typedef TickType_t EventBits_t;
  
  /**
   * event_groups.h
   *<pre>
   EventGroupHandle_t xEventGroupCreate( void );
   </pre>
   *
   * Create a new event group.  This function cannot be called from an interrupt.
   *
   * Although event groups are not related to ticks, for internal implementation
   * reasons the number of bits available for use in an event group is dependent
   * on the configUSE_16_BIT_TICKS setting in FreeRTOSConfig.h.  If
   * configUSE_16_BIT_TICKS is 1 then each event group contains 8 usable bits (bit
   * 0 to bit 7).  If configUSE_16_BIT_TICKS is set to 0 then each event group has
   * 24 usable bits (bit 0 to bit 23).  The EventBits_t type is used to store
   * event bits within an event group.
   *
   * @return If the event group was created then a handle to the event group is
   * returned.  If there was insufficient FreeRTOS heap available to create the
   * event group then NULL is returned.  See http://www.freertos.org/a00111.html
   *
   * Example usage:
     <pre>
  	// Declare a variable to hold the created event group.
  	EventGroupHandle_t xCreatedEventGroup;
  
  	// Attempt to create the event group.
  	xCreatedEventGroup = xEventGroupCreate();
  
  	// Was the event group created successfully?
  	if ( xCreatedEventGroup == NULL )
  	{
  		// The event group was not created because there was insufficient
  		// FreeRTOS heap available.
  	}
  	else
  	{
  		// The event group was created.
  	}
     </pre>
   * \defgroup xEventGroupCreate xEventGroupCreate
   * \ingroup EventGroup
   */
  EventGroupHandle_t xEventGroupCreate( void ) PRIVILEGED_FUNCTION;
  
  /**
   * event_groups.h
   *<pre>
  	EventBits_t xEventGroupWaitBits( 	EventGroupHandle_t xEventGroup,
  										const EventBits_t uxBitsToWaitFor,
  										const BaseType_t xClearOnExit,
  										const BaseType_t xWaitForAllBits,
  										const TickType_t xTicksToWait );
   </pre>
   *
   * [Potentially] block to wait for one or more bits to be set within a
   * previously created event group.
   *
   * This function cannot be called from an interrupt.
   *
   * @param xEventGroup The event group in which the bits are being tested.  The
   * event group must have previously been created using a call to
   * xEventGroupCreate().
   *
   * @param uxBitsToWaitFor A bitwise value that indicates the bit or bits to test
   * inside the event group.  For example, to wait for bit 0 and/or bit 2 set
   * uxBitsToWaitFor to 0x05.  To wait for bits 0 and/or bit 1 and/or bit 2 set
   * uxBitsToWaitFor to 0x07.  Etc.
   *
   * @param xClearOnExit If xClearOnExit is set to pdTRUE then any bits within
   * uxBitsToWaitFor that are set within the event group will be cleared before
   * xEventGroupWaitBits() returns if the wait condition was met (if the function
   * returns for a reason other than a timeout).  If xClearOnExit is set to
   * pdFALSE then the bits set in the event group are not altered when the call to
   * xEventGroupWaitBits() returns.
   *
   * @param xWaitForAllBits If xWaitForAllBits is set to pdTRUE then
   * xEventGroupWaitBits() will return when either all the bits in uxBitsToWaitFor
   * are set or the specified block time expires.  If xWaitForAllBits is set to
   * pdFALSE then xEventGroupWaitBits() will return when any one of the bits set
   * in uxBitsToWaitFor is set or the specified block time expires.  The block
   * time is specified by the xTicksToWait parameter.
   *
   * @param xTicksToWait The maximum amount of time (specified in 'ticks') to wait
   * for one/all (depending on the xWaitForAllBits value) of the bits specified by
   * uxBitsToWaitFor to become set.
   *
   * @return The value of the event group at the time either the bits being waited
   * for became set, or the block time expired.  Test the return value to know
   * which bits were set.  If xEventGroupWaitBits() returned because its timeout
   * expired then not all the bits being waited for will be set.  If
   * xEventGroupWaitBits() returned because the bits it was waiting for were set
   * then the returned value is the event group value before any bits were
   * automatically cleared in the case that xClearOnExit parameter was set to
   * pdTRUE.
   *
   * Example usage:
     <pre>
     #define BIT_0	( 1 << 0 )
     #define BIT_4	( 1 << 4 )
  
     void aFunction( EventGroupHandle_t xEventGroup )
     {
     EventBits_t uxBits;
     const TickType_t xTicksToWait = 100 / portTICK_PERIOD_MS;
  
  		// Wait a maximum of 100ms for either bit 0 or bit 4 to be set within
  		// the event group.  Clear the bits before exiting.
  		uxBits = xEventGroupWaitBits(
  					xEventGroup,	// The event group being tested.
  					BIT_0 | BIT_4,	// The bits within the event group to wait for.
  					pdTRUE,			// BIT_0 and BIT_4 should be cleared before returning.
  					pdFALSE,		// Don't wait for both bits, either bit will do.
  					xTicksToWait );	// Wait a maximum of 100ms for either bit to be set.
  
  		if ( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
  		{
  			// xEventGroupWaitBits() returned because both bits were set.
  		}
  		else if ( ( uxBits & BIT_0 ) != 0 )
  		{
  			// xEventGroupWaitBits() returned because just BIT_0 was set.
  		}
  		else if ( ( uxBits & BIT_4 ) != 0 )
  		{
  			// xEventGroupWaitBits() returned because just BIT_4 was set.
  		}
  		else
  		{
  			// xEventGroupWaitBits() returned because xTicksToWait ticks passed
  			// without either BIT_0 or BIT_4 becoming set.
  		}
     }
     </pre>
   * \defgroup xEventGroupWaitBits xEventGroupWaitBits
   * \ingroup EventGroup
   */
  EventBits_t xEventGroupWaitBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToWaitFor, const BaseType_t xClearOnExit, const BaseType_t xWaitForAllBits, TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
  
  /**
   * event_groups.h
   *<pre>
  	EventBits_t xEventGroupClearBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToClear );
   </pre>
   *
   * Clear bits within an event group.  This function cannot be called from an
   * interrupt.
   *
   * @param xEventGroup The event group in which the bits are to be cleared.
   *
   * @param uxBitsToClear A bitwise value that indicates the bit or bits to clear
   * in the event group.  For example, to clear bit 3 only, set uxBitsToClear to
   * 0x08.  To clear bit 3 and bit 0 set uxBitsToClear to 0x09.
   *
   * @return The value of the event group before the specified bits were cleared.
   *
   * Example usage:
     <pre>
     #define BIT_0	( 1 << 0 )
     #define BIT_4	( 1 << 4 )
  
     void aFunction( EventGroupHandle_t xEventGroup )
     {
     EventBits_t uxBits;
  
  		// Clear bit 0 and bit 4 in xEventGroup.
  		uxBits = xEventGroupClearBits(
  								xEventGroup,	// The event group being updated.
  								BIT_0 | BIT_4 );// The bits being cleared.
  
  		if ( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
  		{
  			// Both bit 0 and bit 4 were set before xEventGroupClearBits() was
  			// called.  Both will now be clear (not set).
  		}
  		else if ( ( uxBits & BIT_0 ) != 0 )
  		{
  			// Bit 0 was set before xEventGroupClearBits() was called.  It will
  			// now be clear.
  		}
  		else if ( ( uxBits & BIT_4 ) != 0 )
  		{
  			// Bit 4 was set before xEventGroupClearBits() was called.  It will
  			// now be clear.
  		}
  		else
  		{
  			// Neither bit 0 nor bit 4 were set in the first place.
  		}
     }
     </pre>
   * \defgroup xEventGroupClearBits xEventGroupClearBits
   * \ingroup EventGroup
   */
  EventBits_t xEventGroupClearBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToClear ) PRIVILEGED_FUNCTION;
  
  /**
   * event_groups.h
   *<pre>
  	BaseType_t xEventGroupClearBitsFromISR( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet );
   </pre>
   *
   * A version of xEventGroupClearBits() that can be called from an interrupt.
   *
   * Setting bits in an event group is not a deterministic operation because there
   * are an unknown number of tasks that may be waiting for the bit or bits being
   * set.  FreeRTOS does not allow nondeterministic operations to be performed
   * while interrupts are disabled, so protects event groups that are accessed
   * from tasks by suspending the scheduler rather than disabling interrupts.  As
   * a result event groups cannot be accessed directly from an interrupt service
   * routine.  Therefore xEventGroupClearBitsFromISR() sends a message to the
   * timer task to have the clear operation performed in the context of the timer
   * task.
   *
   * @param xEventGroup The event group in which the bits are to be cleared.
   *
   * @param uxBitsToClear A bitwise value that indicates the bit or bits to clear.
   * For example, to clear bit 3 only, set uxBitsToClear to 0x08.  To clear bit 3
   * and bit 0 set uxBitsToClear to 0x09.
   *
   * @return If the request to execute the function was posted successfully then
   * pdPASS is returned, otherwise pdFALSE is returned.  pdFALSE will be returned
   * if the timer service queue was full.
   *
   * Example usage:
     <pre>
     #define BIT_0	( 1 << 0 )
     #define BIT_4	( 1 << 4 )
  
     // An event group which it is assumed has already been created by a call to
     // xEventGroupCreate().
     EventGroupHandle_t xEventGroup;
  
     void anInterruptHandler( void )
     {
  		// Clear bit 0 and bit 4 in xEventGroup.
  		xResult = xEventGroupClearBitsFromISR(
  							xEventGroup,	 // The event group being updated.
  							BIT_0 | BIT_4 ); // The bits being set.
  
  		if ( xResult == pdPASS )
  		{
  			// The message was posted successfully.
  		}
    }
     </pre>
   * \defgroup xEventGroupSetBitsFromISR xEventGroupSetBitsFromISR
   * \ingroup EventGroup
   */
  #if ( configUSE_TRACE_FACILITY == 1 )
  	BaseType_t xEventGroupClearBitsFromISR( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet );
  #else
  	#define xEventGroupClearBitsFromISR( xEventGroup, uxBitsToClear ) xTimerPendFunctionCallFromISR( vEventGroupClearBitsCallback, ( void * ) xEventGroup, ( uint32_t ) uxBitsToClear, NULL )
  #endif
  
  /**
   * event_groups.h
   *<pre>
  	EventBits_t xEventGroupSetBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet );
   </pre>
   *
   * Set bits within an event group.
   * This function cannot be called from an interrupt.  xEventGroupSetBitsFromISR()
   * is a version that can be called from an interrupt.
   *
   * Setting bits in an event group will automatically unblock tasks that are
   * blocked waiting for the bits.
   *
   * @param xEventGroup The event group in which the bits are to be set.
   *
   * @param uxBitsToSet A bitwise value that indicates the bit or bits to set.
   * For example, to set bit 3 only, set uxBitsToSet to 0x08.  To set bit 3
   * and bit 0 set uxBitsToSet to 0x09.
   *
   * @return The value of the event group at the time the call to
   * xEventGroupSetBits() returns.  There are two reasons why the returned value
   * might have the bits specified by the uxBitsToSet parameter cleared.  First,
   * if setting a bit results in a task that was waiting for the bit leaving the
   * blocked state then it is possible the bit will be cleared automatically
   * (see the xClearBitOnExit parameter of xEventGroupWaitBits()).  Second, any
   * unblocked (or otherwise Ready state) task that has a priority above that of
   * the task that called xEventGroupSetBits() will execute and may change the
   * event group value before the call to xEventGroupSetBits() returns.
   *
   * Example usage:
     <pre>
     #define BIT_0	( 1 << 0 )
     #define BIT_4	( 1 << 4 )
  
     void aFunction( EventGroupHandle_t xEventGroup )
     {
     EventBits_t uxBits;
  
  		// Set bit 0 and bit 4 in xEventGroup.
  		uxBits = xEventGroupSetBits(
  							xEventGroup,	// The event group being updated.
  							BIT_0 | BIT_4 );// The bits being set.
  
  		if ( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
  		{
  			// Both bit 0 and bit 4 remained set when the function returned.
  		}
  		else if ( ( uxBits & BIT_0 ) != 0 )
  		{
  			// Bit 0 remained set when the function returned, but bit 4 was
  			// cleared.  It might be that bit 4 was cleared automatically as a
  			// task that was waiting for bit 4 was removed from the Blocked
  			// state.
  		}
  		else if ( ( uxBits & BIT_4 ) != 0 )
  		{
  			// Bit 4 remained set when the function returned, but bit 0 was
  			// cleared.  It might be that bit 0 was cleared automatically as a
  			// task that was waiting for bit 0 was removed from the Blocked
  			// state.
  		}
  		else
  		{
  			// Neither bit 0 nor bit 4 remained set.  It might be that a task
  			// was waiting for both of the bits to be set, and the bits were
  			// cleared as the task left the Blocked state.
  		}
     }
     </pre>
   * \defgroup xEventGroupSetBits xEventGroupSetBits
   * \ingroup EventGroup
   */
  EventBits_t xEventGroupSetBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet ) PRIVILEGED_FUNCTION;
  
  /**
   * event_groups.h
   *<pre>
  	BaseType_t xEventGroupSetBitsFromISR( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet, BaseType_t *pxHigherPriorityTaskWoken );
   </pre>
   *
   * A version of xEventGroupSetBits() that can be called from an interrupt.
   *
   * Setting bits in an event group is not a deterministic operation because there
   * are an unknown number of tasks that may be waiting for the bit or bits being
   * set.  FreeRTOS does not allow nondeterministic operations to be performed in
   * interrupts or from critical sections.  Therefore xEventGroupSetBitFromISR()
   * sends a message to the timer task to have the set operation performed in the
   * context of the timer task - where a scheduler lock is used in place of a
   * critical section.
   *
   * @param xEventGroup The event group in which the bits are to be set.
   *
   * @param uxBitsToSet A bitwise value that indicates the bit or bits to set.
   * For example, to set bit 3 only, set uxBitsToSet to 0x08.  To set bit 3
   * and bit 0 set uxBitsToSet to 0x09.
   *
   * @param pxHigherPriorityTaskWoken As mentioned above, calling this function
   * will result in a message being sent to the timer daemon task.  If the
   * priority of the timer daemon task is higher than the priority of the
   * currently running task (the task the interrupt interrupted) then
   * *pxHigherPriorityTaskWoken will be set to pdTRUE by
   * xEventGroupSetBitsFromISR(), indicating that a context switch should be
   * requested before the interrupt exits.  For that reason
   * *pxHigherPriorityTaskWoken must be initialised to pdFALSE.  See the
   * example code below.
   *
   * @return If the request to execute the function was posted successfully then
   * pdPASS is returned, otherwise pdFALSE is returned.  pdFALSE will be returned
   * if the timer service queue was full.
   *
   * Example usage:
     <pre>
     #define BIT_0	( 1 << 0 )
     #define BIT_4	( 1 << 4 )
  
     // An event group which it is assumed has already been created by a call to
     // xEventGroupCreate().
     EventGroupHandle_t xEventGroup;
  
     void anInterruptHandler( void )
     {
     BaseType_t xHigherPriorityTaskWoken, xResult;
  
  		// xHigherPriorityTaskWoken must be initialised to pdFALSE.
  		xHigherPriorityTaskWoken = pdFALSE;
  
  		// Set bit 0 and bit 4 in xEventGroup.
  		xResult = xEventGroupSetBitsFromISR(
  							xEventGroup,	// The event group being updated.
  							BIT_0 | BIT_4   // The bits being set.
  							&xHigherPriorityTaskWoken );
  
  		// Was the message posted successfully?
  		if ( xResult == pdPASS )
  		{
  			// If xHigherPriorityTaskWoken is now set to pdTRUE then a context
  			// switch should be requested.  The macro used is port specific and
  			// will be either portYIELD_FROM_ISR() or portEND_SWITCHING_ISR() -
  			// refer to the documentation page for the port being used.
  			portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
  		}
    }
     </pre>
   * \defgroup xEventGroupSetBitsFromISR xEventGroupSetBitsFromISR
   * \ingroup EventGroup
   */
  #if ( configUSE_TRACE_FACILITY == 1 )
  	BaseType_t xEventGroupSetBitsFromISR( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet, BaseType_t *pxHigherPriorityTaskWoken );
  #else
  	#define xEventGroupSetBitsFromISR( xEventGroup, uxBitsToSet, pxHigherPriorityTaskWoken ) xTimerPendFunctionCallFromISR( vEventGroupSetBitsCallback, ( void * ) xEventGroup, ( uint32_t ) uxBitsToSet, pxHigherPriorityTaskWoken )
  #endif
  
  /**
   * event_groups.h
   *<pre>
  	EventBits_t xEventGroupSync(	EventGroupHandle_t xEventGroup,
  									const EventBits_t uxBitsToSet,
  									const EventBits_t uxBitsToWaitFor,
  									TickType_t xTicksToWait );
   </pre>
   *
   * Atomically set bits within an event group, then wait for a combination of
   * bits to be set within the same event group.  This functionality is typically
   * used to synchronise multiple tasks, where each task has to wait for the other
   * tasks to reach a synchronisation point before proceeding.
   *
   * This function cannot be used from an interrupt.
   *
   * The function will return before its block time expires if the bits specified
   * by the uxBitsToWait parameter are set, or become set within that time.  In
   * this case all the bits specified by uxBitsToWait will be automatically
   * cleared before the function returns.
   *
   * @param xEventGroup The event group in which the bits are being tested.  The
   * event group must have previously been created using a call to
   * xEventGroupCreate().
   *
   * @param uxBitsToSet The bits to set in the event group before determining
   * if, and possibly waiting for, all the bits specified by the uxBitsToWait
   * parameter are set.
   *
   * @param uxBitsToWaitFor A bitwise value that indicates the bit or bits to test
   * inside the event group.  For example, to wait for bit 0 and bit 2 set
   * uxBitsToWaitFor to 0x05.  To wait for bits 0 and bit 1 and bit 2 set
   * uxBitsToWaitFor to 0x07.  Etc.
   *
   * @param xTicksToWait The maximum amount of time (specified in 'ticks') to wait
   * for all of the bits specified by uxBitsToWaitFor to become set.
   *
   * @return The value of the event group at the time either the bits being waited
   * for became set, or the block time expired.  Test the return value to know
   * which bits were set.  If xEventGroupSync() returned because its timeout
   * expired then not all the bits being waited for will be set.  If
   * xEventGroupSync() returned because all the bits it was waiting for were
   * set then the returned value is the event group value before any bits were
   * automatically cleared.
   *
   * Example usage:
   <pre>
   // Bits used by the three tasks.
   #define TASK_0_BIT		( 1 << 0 )
   #define TASK_1_BIT		( 1 << 1 )
   #define TASK_2_BIT		( 1 << 2 )
  
   #define ALL_SYNC_BITS ( TASK_0_BIT | TASK_1_BIT | TASK_2_BIT )
  
   // Use an event group to synchronise three tasks.  It is assumed this event
   // group has already been created elsewhere.
   EventGroupHandle_t xEventBits;
  
   void vTask0( void *pvParameters )
   {
   EventBits_t uxReturn;
   TickType_t xTicksToWait = 100 / portTICK_PERIOD_MS;
  
  	 for ( ;; )
  	 {
  		// Perform task functionality here.
  
  		// Set bit 0 in the event flag to note this task has reached the
  		// sync point.  The other two tasks will set the other two bits defined
  		// by ALL_SYNC_BITS.  All three tasks have reached the synchronisation
  		// point when all the ALL_SYNC_BITS are set.  Wait a maximum of 100ms
  		// for this to happen.
  		uxReturn = xEventGroupSync( xEventBits, TASK_0_BIT, ALL_SYNC_BITS, xTicksToWait );
  
  		if ( ( uxReturn & ALL_SYNC_BITS ) == ALL_SYNC_BITS )
  		{
  			// All three tasks reached the synchronisation point before the call
  			// to xEventGroupSync() timed out.
  		}
  	}
   }
  
   void vTask1( void *pvParameters )
   {
  	 for ( ;; )
  	 {
  		// Perform task functionality here.
  
  		// Set bit 1 in the event flag to note this task has reached the
  		// synchronisation point.  The other two tasks will set the other two
  		// bits defined by ALL_SYNC_BITS.  All three tasks have reached the
  		// synchronisation point when all the ALL_SYNC_BITS are set.  Wait
  		// indefinitely for this to happen.
  		xEventGroupSync( xEventBits, TASK_1_BIT, ALL_SYNC_BITS, portMAX_DELAY );
  
  		// xEventGroupSync() was called with an indefinite block time, so
  		// this task will only reach here if the syncrhonisation was made by all
  		// three tasks, so there is no need to test the return value.
  	 }
   }
  
   void vTask2( void *pvParameters )
   {
  	 for ( ;; )
  	 {
  		// Perform task functionality here.
  
  		// Set bit 2 in the event flag to note this task has reached the
  		// synchronisation point.  The other two tasks will set the other two
  		// bits defined by ALL_SYNC_BITS.  All three tasks have reached the
  		// synchronisation point when all the ALL_SYNC_BITS are set.  Wait
  		// indefinitely for this to happen.
  		xEventGroupSync( xEventBits, TASK_2_BIT, ALL_SYNC_BITS, portMAX_DELAY );
  
  		// xEventGroupSync() was called with an indefinite block time, so
  		// this task will only reach here if the syncrhonisation was made by all
  		// three tasks, so there is no need to test the return value.
  	}
   }
  
   </pre>
   * \defgroup xEventGroupSync xEventGroupSync
   * \ingroup EventGroup
   */
  EventBits_t xEventGroupSync( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet, const EventBits_t uxBitsToWaitFor, TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
  
  
  /**
   * event_groups.h
   *<pre>
  	EventBits_t xEventGroupGetBits( EventGroupHandle_t xEventGroup );
   </pre>
   *
   * Returns the current value of the bits in an event group.  This function
   * cannot be used from an interrupt.
   *
   * @param xEventGroup The event group being queried.
   *
   * @return The event group bits at the time xEventGroupGetBits() was called.
   *
   * \defgroup xEventGroupGetBits xEventGroupGetBits
   * \ingroup EventGroup
   */
  #define xEventGroupGetBits( xEventGroup ) xEventGroupClearBits( xEventGroup, 0 )
  
  /**
   * event_groups.h
   *<pre>
  	EventBits_t xEventGroupGetBitsFromISR( EventGroupHandle_t xEventGroup );
   </pre>
   *
   * A version of xEventGroupGetBits() that can be called from an ISR.
   *
   * @param xEventGroup The event group being queried.
   *
   * @return The event group bits at the time xEventGroupGetBitsFromISR() was called.
   *
   * \defgroup xEventGroupGetBitsFromISR xEventGroupGetBitsFromISR
   * \ingroup EventGroup
   */
  EventBits_t xEventGroupGetBitsFromISR( EventGroupHandle_t xEventGroup );
  
  /**
   * event_groups.h
   *<pre>
  	void xEventGroupDelete( EventGroupHandle_t xEventGroup );
   </pre>
   *
   * Delete an event group that was previously created by a call to
   * xEventGroupCreate().  Tasks that are blocked on the event group will be
   * unblocked and obtain 0 as the event group's value.
   *
   * @param xEventGroup The event group being deleted.
   */
  void vEventGroupDelete( EventGroupHandle_t xEventGroup );
  
  /* For internal use only. */
  void vEventGroupSetBitsCallback( void *pvEventGroup, const uint32_t ulBitsToSet );
  void vEventGroupClearBitsCallback( void *pvEventGroup, const uint32_t ulBitsToClear );
  
  #if (configUSE_TRACE_FACILITY == 1)
  	UBaseType_t uxEventGroupGetNumber( void* xEventGroup );
  #endif
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* EVENT_GROUPS_H */
  
  
  