From 56e86c626df3dbf74c1021210636a7c5d92a49ce Mon Sep 17 00:00:00 2001 From: Dominik Sliwa Date: Tue, 30 Oct 2018 16:31:29 +0100 Subject: move to cmake Signed-off-by: Dominik Sliwa --- freertos/include/event_groups.h | 797 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 797 insertions(+) create mode 100644 freertos/include/event_groups.h (limited to 'freertos/include/event_groups.h') diff --git a/freertos/include/event_groups.h b/freertos/include/event_groups.h new file mode 100644 index 0000000..7331c91 --- /dev/null +++ b/freertos/include/event_groups.h @@ -0,0 +1,797 @@ +/* + FreeRTOS V9.0.0 - Copyright (C) 2016 Real Time Engineers Ltd. + All rights reserved + + VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. + + This file is part of the FreeRTOS distribution. + + FreeRTOS is free software; you can redistribute it and/or modify it under + the terms of the GNU General Public License (version 2) as published by the + Free Software Foundation >>>> AND MODIFIED BY <<<< the FreeRTOS exception. + + *************************************************************************** + >>! NOTE: The modification to the GPL is included to allow you to !<< + >>! distribute a combined work that includes FreeRTOS without being !<< + >>! obliged to provide the source code for proprietary components !<< + >>! outside of the FreeRTOS kernel. !<< + *************************************************************************** + + FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY + WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS + FOR A PARTICULAR PURPOSE. Full license text is available on the following + link: http://www.freertos.org/a00114.html + + *************************************************************************** + * * + * FreeRTOS provides completely free yet professionally developed, * + * robust, strictly quality controlled, supported, and cross * + * platform software that is more than just the market leader, it * + * is the industry's de facto standard. * + * * + * Help yourself get started quickly while simultaneously helping * + * to support the FreeRTOS project by purchasing a FreeRTOS * + * tutorial book, reference manual, or both: * + * http://www.FreeRTOS.org/Documentation * + * * + *************************************************************************** + + http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading + the FAQ page "My application does not run, what could be wrong?". Have you + defined configASSERT()? + + http://www.FreeRTOS.org/support - In return for receiving this top quality + embedded software for free we request you assist our global community by + participating in the support forum. + + http://www.FreeRTOS.org/training - Investing in training allows your team to + be as productive as possible as early as possible. Now you can receive + FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers + Ltd, and the world's leading authority on the world's leading RTOS. + + http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, + including FreeRTOS+Trace - an indispensable productivity tool, a DOS + compatible FAT file system, and our tiny thread aware UDP/IP stack. + + http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate. + Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS. + + http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High + Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS + licenses offer ticketed support, indemnification and commercial middleware. + + http://www.SafeRTOS.com - High Integrity Systems also provide a safety + engineered and independently SIL3 certified version for use in safety and + mission critical applications that require provable dependability. + + 1 tab == 4 spaces! +*/ + +#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 + +/* FreeRTOS includes. */ +#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 + *
+ EventGroupHandle_t xEventGroupCreate( void );
+
+ * + * Create a new event group. + * + * Internally, within the FreeRTOS implementation, event groups use a [small] + * block of memory, in which the event group's structure is stored. If an event + * groups is created using xEventGropuCreate() then the required memory is + * automatically dynamically allocated inside the xEventGroupCreate() function. + * (see http://www.freertos.org/a00111.html). If an event group is created + * using xEventGropuCreateStatic() then the application writer must instead + * provide the memory that will get used by the event group. + * xEventGroupCreateStatic() therefore allows an event group to be created + * without using any dynamic memory allocation. + * + * 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: + 
+	// 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.
+	}
+
+ * \defgroup xEventGroupCreate xEventGroupCreate + * \ingroup EventGroup + */ +#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) + EventGroupHandle_t xEventGroupCreate( void ) PRIVILEGED_FUNCTION; +#endif + +/** + * event_groups.h + *
+ EventGroupHandle_t xEventGroupCreateStatic( EventGroupHandle_t * pxEventGroupBuffer );
+
+ * + * Create a new event group. + * + * Internally, within the FreeRTOS implementation, event groups use a [small] + * block of memory, in which the event group's structure is stored. If an event + * groups is created using xEventGropuCreate() then the required memory is + * automatically dynamically allocated inside the xEventGroupCreate() function. + * (see http://www.freertos.org/a00111.html). If an event group is created + * using xEventGropuCreateStatic() then the application writer must instead + * provide the memory that will get used by the event group. + * xEventGroupCreateStatic() therefore allows an event group to be created + * without using any dynamic memory allocation. + * + * 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. + * + * @param pxEventGroupBuffer pxEventGroupBuffer must point to a variable of type + * StaticEventGroup_t, which will be then be used to hold the event group's data + * structures, removing the need for the memory to be allocated dynamically. + * + * @return If the event group was created then a handle to the event group is + * returned. If pxEventGroupBuffer was NULL then NULL is returned. + * + * Example usage: + 
+	// StaticEventGroup_t is a publicly accessible structure that has the same
+	// size and alignment requirements as the real event group structure.  It is
+	// provided as a mechanism for applications to know the size of the event
+	// group (which is dependent on the architecture and configuration file
+	// settings) without breaking the strict data hiding policy by exposing the
+	// real event group internals.  This StaticEventGroup_t variable is passed
+	// into the xSemaphoreCreateEventGroupStatic() function and is used to store
+	// the event group's data structures
+	StaticEventGroup_t xEventGroupBuffer;
+
+	// Create the event group without dynamically allocating any memory.
+	xEventGroup = xEventGroupCreateStatic( &xEventGroupBuffer );
+
+ */ +#if( configSUPPORT_STATIC_ALLOCATION == 1 ) + EventGroupHandle_t xEventGroupCreateStatic( StaticEventGroup_t *pxEventGroupBuffer ) PRIVILEGED_FUNCTION; +#endif + +/** + * event_groups.h + *
+	EventBits_t xEventGroupWaitBits( 	EventGroupHandle_t xEventGroup,
+										const EventBits_t uxBitsToWaitFor,
+										const BaseType_t xClearOnExit,
+										const BaseType_t xWaitForAllBits,
+										const TickType_t xTicksToWait );
+
+ * + * [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: + 
+   #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.
+		}
+   }
+
+ * \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 + *
+	EventBits_t xEventGroupClearBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToClear );
+
+ * + * 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: + 
+   #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.
+		}
+   }
+
+ * \defgroup xEventGroupClearBits xEventGroupClearBits + * \ingroup EventGroup + */ +EventBits_t xEventGroupClearBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToClear ) PRIVILEGED_FUNCTION; + +/** + * event_groups.h + *
+	BaseType_t xEventGroupClearBitsFromISR( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet );
+
+ * + * 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: + 
+   #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.
+		}
+  }
+
+ * \defgroup xEventGroupClearBitsFromISR xEventGroupClearBitsFromISR + * \ingroup EventGroup + */ +#if( configUSE_TRACE_FACILITY == 1 ) + BaseType_t xEventGroupClearBitsFromISR( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet ) PRIVILEGED_FUNCTION; +#else + #define xEventGroupClearBitsFromISR( xEventGroup, uxBitsToClear ) xTimerPendFunctionCallFromISR( vEventGroupClearBitsCallback, ( void * ) xEventGroup, ( uint32_t ) uxBitsToClear, NULL ) +#endif + +/** + * event_groups.h + *
+	EventBits_t xEventGroupSetBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet );
+
+ * + * 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: + 
+   #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.
+		}
+   }
+
+ * \defgroup xEventGroupSetBits xEventGroupSetBits + * \ingroup EventGroup + */ +EventBits_t xEventGroupSetBits( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet ) PRIVILEGED_FUNCTION; + +/** + * event_groups.h + *
+	BaseType_t xEventGroupSetBitsFromISR( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet, BaseType_t *pxHigherPriorityTaskWoken );
+
+ * + * 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 xEventGroupSetBitsFromISR() + * 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: + 
+   #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 );
+		}
+  }
+
+ * \defgroup xEventGroupSetBitsFromISR xEventGroupSetBitsFromISR + * \ingroup EventGroup + */ +#if( configUSE_TRACE_FACILITY == 1 ) + BaseType_t xEventGroupSetBitsFromISR( EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet, BaseType_t *pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION; +#else + #define xEventGroupSetBitsFromISR( xEventGroup, uxBitsToSet, pxHigherPriorityTaskWoken ) xTimerPendFunctionCallFromISR( vEventGroupSetBitsCallback, ( void * ) xEventGroup, ( uint32_t ) uxBitsToSet, pxHigherPriorityTaskWoken ) +#endif + +/** + * event_groups.h + *
+	EventBits_t xEventGroupSync(	EventGroupHandle_t xEventGroup,
+									const EventBits_t uxBitsToSet,
+									const EventBits_t uxBitsToWaitFor,
+									TickType_t xTicksToWait );
+
+ * + * 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: + 
+ // 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.
+	}
+ }
+
+
+ * \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 + *
+	EventBits_t xEventGroupGetBits( EventGroupHandle_t xEventGroup );
+
+ * + * 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 + *
+	EventBits_t xEventGroupGetBitsFromISR( EventGroupHandle_t xEventGroup );
+
+ * + * 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 ) PRIVILEGED_FUNCTION; + +/** + * event_groups.h + *
+	void xEventGroupDelete( EventGroupHandle_t xEventGroup );
+
+ * + * 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 ) PRIVILEGED_FUNCTION; + +/* For internal use only. */ +void vEventGroupSetBitsCallback( void *pvEventGroup, const uint32_t ulBitsToSet ) PRIVILEGED_FUNCTION; +void vEventGroupClearBitsCallback( void *pvEventGroup, const uint32_t ulBitsToClear ) PRIVILEGED_FUNCTION; + + +#if (configUSE_TRACE_FACILITY == 1) + UBaseType_t uxEventGroupGetNumber( void* xEventGroup ) PRIVILEGED_FUNCTION; +#endif + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT_GROUPS_H */ + + -- cgit v1.2.3