762 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			762 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |     FreeRTOS V7.3.0 - Copyright (C) 2012 Real Time Engineers Ltd. | ||
|  | 
 | ||
|  |     FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME.  PLEASE VISIT  | ||
|  |     http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
 | ||
|  | 
 | ||
|  |     *************************************************************************** | ||
|  |      *                                                                       * | ||
|  |      *    FreeRTOS tutorial books are available in pdf and paperback.        * | ||
|  |      *    Complete, revised, and edited pdf reference manuals are also       * | ||
|  |      *    available.                                                         * | ||
|  |      *                                                                       * | ||
|  |      *    Purchasing FreeRTOS documentation will not only help you, by       * | ||
|  |      *    ensuring you get running as quickly as possible and with an        * | ||
|  |      *    in-depth knowledge of how to use FreeRTOS, it will also help       * | ||
|  |      *    the FreeRTOS project to continue with its mission of providing     * | ||
|  |      *    professional grade, cross platform, de facto standard solutions    * | ||
|  |      *    for microcontrollers - completely free of charge!                  * | ||
|  |      *                                                                       * | ||
|  |      *    >>> See http://www.FreeRTOS.org/Documentation for details. <<<     *
 | ||
|  |      *                                                                       * | ||
|  |      *    Thank you for using FreeRTOS, and thank you for your support!      * | ||
|  |      *                                                                       * | ||
|  |     *************************************************************************** | ||
|  | 
 | ||
|  | 
 | ||
|  |     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.  See the GNU General Public License for | ||
|  |     more details. You should have received a copy of the GNU General Public | ||
|  |     License and the FreeRTOS license exception along with FreeRTOS; if not it | ||
|  |     can be viewed here: http://www.freertos.org/a00114.html and also obtained
 | ||
|  |     by writing to Richard Barry, contact details for whom are available on the | ||
|  |     FreeRTOS WEB site. | ||
|  | 
 | ||
|  |     1 tab == 4 spaces! | ||
|  |      | ||
|  |     *************************************************************************** | ||
|  |      *                                                                       * | ||
|  |      *    Having a problem?  Start by reading the FAQ "My application does   * | ||
|  |      *    not run, what could be wrong?"                                     * | ||
|  |      *                                                                       * | ||
|  |      *    http://www.FreeRTOS.org/FAQHelp.html                               *
 | ||
|  |      *                                                                       * | ||
|  |     *************************************************************************** | ||
|  | 
 | ||
|  |      | ||
|  |     http://www.FreeRTOS.org - Documentation, training, latest versions, license 
 | ||
|  |     and contact details.   | ||
|  |      | ||
|  |     http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
 | ||
|  |     including FreeRTOS+Trace - an indispensable productivity tool. | ||
|  | 
 | ||
|  |     Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell  | ||
|  |     the code with commercial support, indemnification, and middleware, under  | ||
|  |     the OpenRTOS brand: http://www.OpenRTOS.com.  High Integrity Systems also
 | ||
|  |     provide a safety engineered and independently SIL3 certified version under  | ||
|  |     the SafeRTOS brand: http://www.SafeRTOS.com.
 | ||
|  | */ | ||
|  | 
 | ||
|  | #ifndef CO_ROUTINE_H
 | ||
|  | #define CO_ROUTINE_H
 | ||
|  | 
 | ||
|  | #ifndef INC_FREERTOS_H
 | ||
|  | 	#error "include FreeRTOS.h must appear in source files before include croutine.h"
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #include "list.h"
 | ||
|  | 
 | ||
|  | #ifdef __cplusplus
 | ||
|  | extern "C" { | ||
|  | #endif
 | ||
|  | 
 | ||
|  | /* Used to hide the implementation of the co-routine control block.  The
 | ||
|  | control block structure however has to be included in the header due to | ||
|  | the macro implementation of the co-routine functionality. */ | ||
|  | typedef void * xCoRoutineHandle; | ||
|  | 
 | ||
|  | /* Defines the prototype to which co-routine functions must conform. */ | ||
|  | typedef void (*crCOROUTINE_CODE)( xCoRoutineHandle, unsigned portBASE_TYPE ); | ||
|  | 
 | ||
|  | typedef struct corCoRoutineControlBlock | ||
|  | { | ||
|  | 	crCOROUTINE_CODE 		pxCoRoutineFunction; | ||
|  | 	xListItem				xGenericListItem;	/*< List item used to place the CRCB in ready and blocked queues. */ | ||
|  | 	xListItem				xEventListItem;		/*< List item used to place the CRCB in event lists. */ | ||
|  | 	unsigned portBASE_TYPE 	uxPriority;			/*< The priority of the co-routine in relation to other co-routines. */ | ||
|  | 	unsigned portBASE_TYPE 	uxIndex;			/*< Used to distinguish between co-routines when multiple co-routines use the same co-routine function. */ | ||
|  | 	unsigned short 		uxState;			/*< Used internally by the co-routine implementation. */ | ||
|  | } corCRCB; /* Co-routine control block.  Note must be identical in size down to uxPriority with tskTCB. */ | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * croutine. h | ||
|  |  *<pre> | ||
|  |  portBASE_TYPE xCoRoutineCreate( | ||
|  |                                  crCOROUTINE_CODE pxCoRoutineCode, | ||
|  |                                  unsigned portBASE_TYPE uxPriority, | ||
|  |                                  unsigned portBASE_TYPE uxIndex | ||
|  |                                );</pre> | ||
|  |  * | ||
|  |  * Create a new co-routine and add it to the list of co-routines that are | ||
|  |  * ready to run. | ||
|  |  * | ||
|  |  * @param pxCoRoutineCode Pointer to the co-routine function.  Co-routine | ||
|  |  * functions require special syntax - see the co-routine section of the WEB | ||
|  |  * documentation for more information. | ||
|  |  * | ||
|  |  * @param uxPriority The priority with respect to other co-routines at which | ||
|  |  *  the co-routine will run. | ||
|  |  * | ||
|  |  * @param uxIndex Used to distinguish between different co-routines that | ||
|  |  * execute the same function.  See the example below and the co-routine section | ||
|  |  * of the WEB documentation for further information. | ||
|  |  * | ||
|  |  * @return pdPASS if the co-routine was successfully created and added to a ready | ||
|  |  * list, otherwise an error code defined with ProjDefs.h. | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |    <pre> | ||
|  |  // Co-routine to be created.
 | ||
|  |  void vFlashCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex ) | ||
|  |  { | ||
|  |  // Variables in co-routines must be declared static if they must maintain value across a blocking call.
 | ||
|  |  // This may not be necessary for const variables.
 | ||
|  |  static const char cLedToFlash[ 2 ] = { 5, 6 }; | ||
|  |  static const portTickType uxFlashRates[ 2 ] = { 200, 400 }; | ||
|  | 
 | ||
|  |      // Must start every co-routine with a call to crSTART();
 | ||
|  |      crSTART( xHandle ); | ||
|  | 
 | ||
|  |      for( ;; ) | ||
|  |      { | ||
|  |          // This co-routine just delays for a fixed period, then toggles
 | ||
|  |          // an LED.  Two co-routines are created using this function, so
 | ||
|  |          // the uxIndex parameter is used to tell the co-routine which
 | ||
|  |          // LED to flash and how long to delay.  This assumes xQueue has
 | ||
|  |          // already been created.
 | ||
|  |          vParTestToggleLED( cLedToFlash[ uxIndex ] ); | ||
|  |          crDELAY( xHandle, uxFlashRates[ uxIndex ] ); | ||
|  |      } | ||
|  | 
 | ||
|  |      // Must end every co-routine with a call to crEND();
 | ||
|  |      crEND(); | ||
|  |  } | ||
|  | 
 | ||
|  |  // Function that creates two co-routines.
 | ||
|  |  void vOtherFunction( void ) | ||
|  |  { | ||
|  |  unsigned char ucParameterToPass; | ||
|  |  xTaskHandle xHandle; | ||
|  | 		 | ||
|  |      // Create two co-routines at priority 0.  The first is given index 0
 | ||
|  |      // so (from the code above) toggles LED 5 every 200 ticks.  The second
 | ||
|  |      // is given index 1 so toggles LED 6 every 400 ticks.
 | ||
|  |      for( uxIndex = 0; uxIndex < 2; uxIndex++ ) | ||
|  |      { | ||
|  |          xCoRoutineCreate( vFlashCoRoutine, 0, uxIndex ); | ||
|  |      } | ||
|  |  } | ||
|  |    </pre> | ||
|  |  * \defgroup xCoRoutineCreate xCoRoutineCreate | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | signed portBASE_TYPE xCoRoutineCreate( crCOROUTINE_CODE pxCoRoutineCode, unsigned portBASE_TYPE uxPriority, unsigned portBASE_TYPE uxIndex ); | ||
|  | 
 | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * croutine. h | ||
|  |  *<pre> | ||
|  |  void vCoRoutineSchedule( void );</pre> | ||
|  |  * | ||
|  |  * Run a co-routine. | ||
|  |  * | ||
|  |  * vCoRoutineSchedule() executes the highest priority co-routine that is able | ||
|  |  * to run.  The co-routine will execute until it either blocks, yields or is | ||
|  |  * preempted by a task.  Co-routines execute cooperatively so one | ||
|  |  * co-routine cannot be preempted by another, but can be preempted by a task. | ||
|  |  * | ||
|  |  * If an application comprises of both tasks and co-routines then | ||
|  |  * vCoRoutineSchedule should be called from the idle task (in an idle task | ||
|  |  * hook). | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |    <pre> | ||
|  |  // This idle task hook will schedule a co-routine each time it is called.
 | ||
|  |  // The rest of the idle task will execute between co-routine calls.
 | ||
|  |  void vApplicationIdleHook( void ) | ||
|  |  { | ||
|  | 	vCoRoutineSchedule(); | ||
|  |  } | ||
|  | 
 | ||
|  |  // Alternatively, if you do not require any other part of the idle task to
 | ||
|  |  // execute, the idle task hook can call vCoRoutineScheduler() within an
 | ||
|  |  // infinite loop.
 | ||
|  |  void vApplicationIdleHook( void ) | ||
|  |  { | ||
|  |     for( ;; ) | ||
|  |     { | ||
|  |         vCoRoutineSchedule(); | ||
|  |     } | ||
|  |  } | ||
|  |  </pre> | ||
|  |  * \defgroup vCoRoutineSchedule vCoRoutineSchedule | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | void vCoRoutineSchedule( void ); | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * croutine. h | ||
|  |  * <pre> | ||
|  |  crSTART( xCoRoutineHandle xHandle );</pre> | ||
|  |  * | ||
|  |  * This macro MUST always be called at the start of a co-routine function. | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |    <pre> | ||
|  |  // Co-routine to be created.
 | ||
|  |  void vACoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex ) | ||
|  |  { | ||
|  |  // Variables in co-routines must be declared static if they must maintain value across a blocking call.
 | ||
|  |  static long ulAVariable; | ||
|  | 
 | ||
|  |      // Must start every co-routine with a call to crSTART();
 | ||
|  |      crSTART( xHandle ); | ||
|  | 
 | ||
|  |      for( ;; ) | ||
|  |      { | ||
|  |           // Co-routine functionality goes here.
 | ||
|  |      } | ||
|  | 
 | ||
|  |      // Must end every co-routine with a call to crEND();
 | ||
|  |      crEND(); | ||
|  |  }</pre> | ||
|  |  * \defgroup crSTART crSTART | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | #define crSTART( pxCRCB ) switch( ( ( corCRCB * )( pxCRCB ) )->uxState ) { case 0:
 | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * croutine. h | ||
|  |  * <pre> | ||
|  |  crEND();</pre> | ||
|  |  * | ||
|  |  * This macro MUST always be called at the end of a co-routine function. | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |    <pre> | ||
|  |  // Co-routine to be created.
 | ||
|  |  void vACoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex ) | ||
|  |  { | ||
|  |  // Variables in co-routines must be declared static if they must maintain value across a blocking call.
 | ||
|  |  static long ulAVariable; | ||
|  | 
 | ||
|  |      // Must start every co-routine with a call to crSTART();
 | ||
|  |      crSTART( xHandle ); | ||
|  | 
 | ||
|  |      for( ;; ) | ||
|  |      { | ||
|  |           // Co-routine functionality goes here.
 | ||
|  |      } | ||
|  | 
 | ||
|  |      // Must end every co-routine with a call to crEND();
 | ||
|  |      crEND(); | ||
|  |  }</pre> | ||
|  |  * \defgroup crSTART crSTART | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | #define crEND() }
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * These macros are intended for internal use by the co-routine implementation | ||
|  |  * only.  The macros should not be used directly by application writers. | ||
|  |  */ | ||
|  | #define crSET_STATE0( xHandle ) ( ( corCRCB * )( xHandle ) )->uxState = (__LINE__ * 2); return; case (__LINE__ * 2):
 | ||
|  | #define crSET_STATE1( xHandle ) ( ( corCRCB * )( xHandle ) )->uxState = ((__LINE__ * 2)+1); return; case ((__LINE__ * 2)+1):
 | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * croutine. h | ||
|  |  *<pre> | ||
|  |  crDELAY( xCoRoutineHandle xHandle, portTickType xTicksToDelay );</pre> | ||
|  |  * | ||
|  |  * Delay a co-routine for a fixed period of time. | ||
|  |  * | ||
|  |  * crDELAY can only be called from the co-routine function itself - not | ||
|  |  * from within a function called by the co-routine function.  This is because | ||
|  |  * co-routines do not maintain their own stack. | ||
|  |  * | ||
|  |  * @param xHandle The handle of the co-routine to delay.  This is the xHandle | ||
|  |  * parameter of the co-routine function. | ||
|  |  * | ||
|  |  * @param xTickToDelay The number of ticks that the co-routine should delay | ||
|  |  * for.  The actual amount of time this equates to is defined by | ||
|  |  * configTICK_RATE_HZ (set in FreeRTOSConfig.h).  The constant portTICK_RATE_MS | ||
|  |  * can be used to convert ticks to milliseconds. | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |    <pre> | ||
|  |  // Co-routine to be created.
 | ||
|  |  void vACoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex ) | ||
|  |  { | ||
|  |  // Variables in co-routines must be declared static if they must maintain value across a blocking call.
 | ||
|  |  // This may not be necessary for const variables.
 | ||
|  |  // We are to delay for 200ms.
 | ||
|  |  static const xTickType xDelayTime = 200 / portTICK_RATE_MS; | ||
|  | 
 | ||
|  |      // Must start every co-routine with a call to crSTART();
 | ||
|  |      crSTART( xHandle ); | ||
|  | 
 | ||
|  |      for( ;; ) | ||
|  |      { | ||
|  |         // Delay for 200ms.
 | ||
|  |         crDELAY( xHandle, xDelayTime ); | ||
|  | 
 | ||
|  |         // Do something here.
 | ||
|  |      } | ||
|  | 
 | ||
|  |      // Must end every co-routine with a call to crEND();
 | ||
|  |      crEND(); | ||
|  |  }</pre> | ||
|  |  * \defgroup crDELAY crDELAY | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | #define crDELAY( xHandle, xTicksToDelay )												\
 | ||
|  | 	if( ( xTicksToDelay ) > 0 )															\ | ||
|  | 	{																					\ | ||
|  | 		vCoRoutineAddToDelayedList( ( xTicksToDelay ), NULL );							\ | ||
|  | 	}																					\ | ||
|  | 	crSET_STATE0( ( xHandle ) ); | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * <pre> | ||
|  |  crQUEUE_SEND( | ||
|  |                   xCoRoutineHandle xHandle, | ||
|  |                   xQueueHandle pxQueue, | ||
|  |                   void *pvItemToQueue, | ||
|  |                   portTickType xTicksToWait, | ||
|  |                   portBASE_TYPE *pxResult | ||
|  |              )</pre> | ||
|  |  * | ||
|  |  * The macro's crQUEUE_SEND() and crQUEUE_RECEIVE() are the co-routine | ||
|  |  * equivalent to the xQueueSend() and xQueueReceive() functions used by tasks. | ||
|  |  * | ||
|  |  * crQUEUE_SEND and crQUEUE_RECEIVE can only be used from a co-routine whereas | ||
|  |  * xQueueSend() and xQueueReceive() can only be used from tasks. | ||
|  |  * | ||
|  |  * crQUEUE_SEND can only be called from the co-routine function itself - not | ||
|  |  * from within a function called by the co-routine function.  This is because | ||
|  |  * co-routines do not maintain their own stack. | ||
|  |  * | ||
|  |  * See the co-routine section of the WEB documentation for information on | ||
|  |  * passing data between tasks and co-routines and between ISR's and | ||
|  |  * co-routines. | ||
|  |  * | ||
|  |  * @param xHandle The handle of the calling co-routine.  This is the xHandle | ||
|  |  * parameter of the co-routine function. | ||
|  |  * | ||
|  |  * @param pxQueue The handle of the queue on which the data will be posted. | ||
|  |  * The handle is obtained as the return value when the queue is created using | ||
|  |  * the xQueueCreate() API function. | ||
|  |  * | ||
|  |  * @param pvItemToQueue A pointer to the data being posted onto the queue. | ||
|  |  * The number of bytes of each queued item is specified when the queue is | ||
|  |  * created.  This number of bytes is copied from pvItemToQueue into the queue | ||
|  |  * itself. | ||
|  |  * | ||
|  |  * @param xTickToDelay The number of ticks that the co-routine should block | ||
|  |  * to wait for space to become available on the queue, should space not be | ||
|  |  * available immediately. The actual amount of time this equates to is defined | ||
|  |  * by configTICK_RATE_HZ (set in FreeRTOSConfig.h).  The constant | ||
|  |  * portTICK_RATE_MS can be used to convert ticks to milliseconds (see example | ||
|  |  * below). | ||
|  |  * | ||
|  |  * @param pxResult The variable pointed to by pxResult will be set to pdPASS if | ||
|  |  * data was successfully posted onto the queue, otherwise it will be set to an | ||
|  |  * error defined within ProjDefs.h. | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |    <pre> | ||
|  |  // Co-routine function that blocks for a fixed period then posts a number onto
 | ||
|  |  // a queue.
 | ||
|  |  static void prvCoRoutineFlashTask( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex ) | ||
|  |  { | ||
|  |  // Variables in co-routines must be declared static if they must maintain value across a blocking call.
 | ||
|  |  static portBASE_TYPE xNumberToPost = 0; | ||
|  |  static portBASE_TYPE xResult; | ||
|  | 
 | ||
|  |     // Co-routines must begin with a call to crSTART().
 | ||
|  |     crSTART( xHandle ); | ||
|  | 
 | ||
|  |     for( ;; ) | ||
|  |     { | ||
|  |         // This assumes the queue has already been created.
 | ||
|  |         crQUEUE_SEND( xHandle, xCoRoutineQueue, &xNumberToPost, NO_DELAY, &xResult ); | ||
|  | 
 | ||
|  |         if( xResult != pdPASS ) | ||
|  |         { | ||
|  |             // The message was not posted!
 | ||
|  |         } | ||
|  | 
 | ||
|  |         // Increment the number to be posted onto the queue.
 | ||
|  |         xNumberToPost++; | ||
|  | 
 | ||
|  |         // Delay for 100 ticks.
 | ||
|  |         crDELAY( xHandle, 100 ); | ||
|  |     } | ||
|  | 
 | ||
|  |     // Co-routines must end with a call to crEND().
 | ||
|  |     crEND(); | ||
|  |  }</pre> | ||
|  |  * \defgroup crQUEUE_SEND crQUEUE_SEND | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | #define crQUEUE_SEND( xHandle, pxQueue, pvItemToQueue, xTicksToWait, pxResult )			\
 | ||
|  | {																						\ | ||
|  | 	*( pxResult ) = xQueueCRSend( ( pxQueue) , ( pvItemToQueue) , ( xTicksToWait ) );	\ | ||
|  | 	if( *( pxResult ) == errQUEUE_BLOCKED )												\ | ||
|  | 	{																					\ | ||
|  | 		crSET_STATE0( ( xHandle ) );													\ | ||
|  | 		*pxResult = xQueueCRSend( ( pxQueue ), ( pvItemToQueue ), 0 );					\ | ||
|  | 	}																					\ | ||
|  | 	if( *pxResult == errQUEUE_YIELD )													\ | ||
|  | 	{																					\ | ||
|  | 		crSET_STATE1( ( xHandle ) );													\ | ||
|  | 		*pxResult = pdPASS;																\ | ||
|  | 	}																					\ | ||
|  | } | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * croutine. h | ||
|  |  * <pre> | ||
|  |   crQUEUE_RECEIVE( | ||
|  |                      xCoRoutineHandle xHandle, | ||
|  |                      xQueueHandle pxQueue, | ||
|  |                      void *pvBuffer, | ||
|  |                      portTickType xTicksToWait, | ||
|  |                      portBASE_TYPE *pxResult | ||
|  |                  )</pre> | ||
|  |  * | ||
|  |  * The macro's crQUEUE_SEND() and crQUEUE_RECEIVE() are the co-routine | ||
|  |  * equivalent to the xQueueSend() and xQueueReceive() functions used by tasks. | ||
|  |  * | ||
|  |  * crQUEUE_SEND and crQUEUE_RECEIVE can only be used from a co-routine whereas | ||
|  |  * xQueueSend() and xQueueReceive() can only be used from tasks. | ||
|  |  * | ||
|  |  * crQUEUE_RECEIVE can only be called from the co-routine function itself - not | ||
|  |  * from within a function called by the co-routine function.  This is because | ||
|  |  * co-routines do not maintain their own stack. | ||
|  |  * | ||
|  |  * See the co-routine section of the WEB documentation for information on | ||
|  |  * passing data between tasks and co-routines and between ISR's and | ||
|  |  * co-routines. | ||
|  |  * | ||
|  |  * @param xHandle The handle of the calling co-routine.  This is the xHandle | ||
|  |  * parameter of the co-routine function. | ||
|  |  * | ||
|  |  * @param pxQueue The handle of the queue from which the data will be received. | ||
|  |  * The handle is obtained as the return value when the queue is created using | ||
|  |  * the xQueueCreate() API function. | ||
|  |  * | ||
|  |  * @param pvBuffer The buffer into which the received item is to be copied. | ||
|  |  * The number of bytes of each queued item is specified when the queue is | ||
|  |  * created.  This number of bytes is copied into pvBuffer. | ||
|  |  * | ||
|  |  * @param xTickToDelay The number of ticks that the co-routine should block | ||
|  |  * to wait for data to become available from the queue, should data not be | ||
|  |  * available immediately. The actual amount of time this equates to is defined | ||
|  |  * by configTICK_RATE_HZ (set in FreeRTOSConfig.h).  The constant | ||
|  |  * portTICK_RATE_MS can be used to convert ticks to milliseconds (see the | ||
|  |  * crQUEUE_SEND example). | ||
|  |  * | ||
|  |  * @param pxResult The variable pointed to by pxResult will be set to pdPASS if | ||
|  |  * data was successfully retrieved from the queue, otherwise it will be set to | ||
|  |  * an error code as defined within ProjDefs.h. | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |  <pre> | ||
|  |  // A co-routine receives the number of an LED to flash from a queue.  It
 | ||
|  |  // blocks on the queue until the number is received.
 | ||
|  |  static void prvCoRoutineFlashWorkTask( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex ) | ||
|  |  { | ||
|  |  // Variables in co-routines must be declared static if they must maintain value across a blocking call.
 | ||
|  |  static portBASE_TYPE xResult; | ||
|  |  static unsigned portBASE_TYPE uxLEDToFlash; | ||
|  | 
 | ||
|  |     // All co-routines must start with a call to crSTART().
 | ||
|  |     crSTART( xHandle ); | ||
|  | 
 | ||
|  |     for( ;; ) | ||
|  |     { | ||
|  |         // Wait for data to become available on the queue.
 | ||
|  |         crQUEUE_RECEIVE( xHandle, xCoRoutineQueue, &uxLEDToFlash, portMAX_DELAY, &xResult ); | ||
|  | 
 | ||
|  |         if( xResult == pdPASS ) | ||
|  |         { | ||
|  |             // We received the LED to flash - flash it!
 | ||
|  |             vParTestToggleLED( uxLEDToFlash ); | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     crEND(); | ||
|  |  }</pre> | ||
|  |  * \defgroup crQUEUE_RECEIVE crQUEUE_RECEIVE | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | #define crQUEUE_RECEIVE( xHandle, pxQueue, pvBuffer, xTicksToWait, pxResult )			\
 | ||
|  | {																						\ | ||
|  | 	*( pxResult ) = xQueueCRReceive( ( pxQueue) , ( pvBuffer ), ( xTicksToWait ) );		\ | ||
|  | 	if( *( pxResult ) == errQUEUE_BLOCKED ) 											\ | ||
|  | 	{																					\ | ||
|  | 		crSET_STATE0( ( xHandle ) );													\ | ||
|  | 		*( pxResult ) = xQueueCRReceive( ( pxQueue) , ( pvBuffer ), 0 );				\ | ||
|  | 	}																					\ | ||
|  | 	if( *( pxResult ) == errQUEUE_YIELD )												\ | ||
|  | 	{																					\ | ||
|  | 		crSET_STATE1( ( xHandle ) );													\ | ||
|  | 		*( pxResult ) = pdPASS;															\ | ||
|  | 	}																					\ | ||
|  | } | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * croutine. h | ||
|  |  * <pre> | ||
|  |   crQUEUE_SEND_FROM_ISR( | ||
|  |                             xQueueHandle pxQueue, | ||
|  |                             void *pvItemToQueue, | ||
|  |                             portBASE_TYPE xCoRoutinePreviouslyWoken | ||
|  |                        )</pre> | ||
|  |  * | ||
|  |  * The macro's crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() are the | ||
|  |  * co-routine equivalent to the xQueueSendFromISR() and xQueueReceiveFromISR() | ||
|  |  * functions used by tasks. | ||
|  |  * | ||
|  |  * crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() can only be used to | ||
|  |  * pass data between a co-routine and and ISR, whereas xQueueSendFromISR() and | ||
|  |  * xQueueReceiveFromISR() can only be used to pass data between a task and and | ||
|  |  * ISR. | ||
|  |  * | ||
|  |  * crQUEUE_SEND_FROM_ISR can only be called from an ISR to send data to a queue | ||
|  |  * that is being used from within a co-routine. | ||
|  |  * | ||
|  |  * See the co-routine section of the WEB documentation for information on | ||
|  |  * passing data between tasks and co-routines and between ISR's and | ||
|  |  * co-routines. | ||
|  |  * | ||
|  |  * @param xQueue The handle to the queue on which the item is to be posted. | ||
|  |  * | ||
|  |  * @param pvItemToQueue A pointer to the item that is to be placed on the | ||
|  |  * queue.  The size of the items the queue will hold was defined when the | ||
|  |  * queue was created, so this many bytes will be copied from pvItemToQueue | ||
|  |  * into the queue storage area. | ||
|  |  * | ||
|  |  * @param xCoRoutinePreviouslyWoken This is included so an ISR can post onto | ||
|  |  * the same queue multiple times from a single interrupt.  The first call | ||
|  |  * should always pass in pdFALSE.  Subsequent calls should pass in | ||
|  |  * the value returned from the previous call. | ||
|  |  * | ||
|  |  * @return pdTRUE if a co-routine was woken by posting onto the queue.  This is | ||
|  |  * used by the ISR to determine if a context switch may be required following | ||
|  |  * the ISR. | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |  <pre> | ||
|  |  // A co-routine that blocks on a queue waiting for characters to be received.
 | ||
|  |  static void vReceivingCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex ) | ||
|  |  { | ||
|  |  char cRxedChar; | ||
|  |  portBASE_TYPE xResult; | ||
|  | 
 | ||
|  |      // All co-routines must start with a call to crSTART().
 | ||
|  |      crSTART( xHandle ); | ||
|  | 
 | ||
|  |      for( ;; ) | ||
|  |      { | ||
|  |          // Wait for data to become available on the queue.  This assumes the
 | ||
|  |          // queue xCommsRxQueue has already been created!
 | ||
|  |          crQUEUE_RECEIVE( xHandle, xCommsRxQueue, &uxLEDToFlash, portMAX_DELAY, &xResult ); | ||
|  | 
 | ||
|  |          // Was a character received?
 | ||
|  |          if( xResult == pdPASS ) | ||
|  |          { | ||
|  |              // Process the character here.
 | ||
|  |          } | ||
|  |      } | ||
|  | 
 | ||
|  |      // All co-routines must end with a call to crEND().
 | ||
|  |      crEND(); | ||
|  |  } | ||
|  | 
 | ||
|  |  // An ISR that uses a queue to send characters received on a serial port to
 | ||
|  |  // a co-routine.
 | ||
|  |  void vUART_ISR( void ) | ||
|  |  { | ||
|  |  char cRxedChar; | ||
|  |  portBASE_TYPE xCRWokenByPost = pdFALSE; | ||
|  | 
 | ||
|  |      // We loop around reading characters until there are none left in the UART.
 | ||
|  |      while( UART_RX_REG_NOT_EMPTY() ) | ||
|  |      { | ||
|  |          // Obtain the character from the UART.
 | ||
|  |          cRxedChar = UART_RX_REG; | ||
|  | 
 | ||
|  |          // Post the character onto a queue.  xCRWokenByPost will be pdFALSE
 | ||
|  |          // the first time around the loop.  If the post causes a co-routine
 | ||
|  |          // to be woken (unblocked) then xCRWokenByPost will be set to pdTRUE.
 | ||
|  |          // In this manner we can ensure that if more than one co-routine is
 | ||
|  |          // blocked on the queue only one is woken by this ISR no matter how
 | ||
|  |          // many characters are posted to the queue.
 | ||
|  |          xCRWokenByPost = crQUEUE_SEND_FROM_ISR( xCommsRxQueue, &cRxedChar, xCRWokenByPost ); | ||
|  |      } | ||
|  |  }</pre> | ||
|  |  * \defgroup crQUEUE_SEND_FROM_ISR crQUEUE_SEND_FROM_ISR | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | #define crQUEUE_SEND_FROM_ISR( pxQueue, pvItemToQueue, xCoRoutinePreviouslyWoken ) xQueueCRSendFromISR( ( pxQueue ), ( pvItemToQueue ), ( xCoRoutinePreviouslyWoken ) )
 | ||
|  | 
 | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * croutine. h | ||
|  |  * <pre> | ||
|  |   crQUEUE_SEND_FROM_ISR( | ||
|  |                             xQueueHandle pxQueue, | ||
|  |                             void *pvBuffer, | ||
|  |                             portBASE_TYPE * pxCoRoutineWoken | ||
|  |                        )</pre> | ||
|  |  * | ||
|  |  * The macro's crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() are the | ||
|  |  * co-routine equivalent to the xQueueSendFromISR() and xQueueReceiveFromISR() | ||
|  |  * functions used by tasks. | ||
|  |  * | ||
|  |  * crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() can only be used to | ||
|  |  * pass data between a co-routine and and ISR, whereas xQueueSendFromISR() and | ||
|  |  * xQueueReceiveFromISR() can only be used to pass data between a task and and | ||
|  |  * ISR. | ||
|  |  * | ||
|  |  * crQUEUE_RECEIVE_FROM_ISR can only be called from an ISR to receive data | ||
|  |  * from a queue that is being used from within a co-routine (a co-routine | ||
|  |  * posted to the queue). | ||
|  |  * | ||
|  |  * See the co-routine section of the WEB documentation for information on | ||
|  |  * passing data between tasks and co-routines and between ISR's and | ||
|  |  * co-routines. | ||
|  |  * | ||
|  |  * @param xQueue The handle to the queue on which the item is to be posted. | ||
|  |  * | ||
|  |  * @param pvBuffer A pointer to a buffer into which the received item will be | ||
|  |  * placed.  The size of the items the queue will hold was defined when the | ||
|  |  * queue was created, so this many bytes will be copied from the queue into | ||
|  |  * pvBuffer. | ||
|  |  * | ||
|  |  * @param pxCoRoutineWoken A co-routine may be blocked waiting for space to become | ||
|  |  * available on the queue.  If crQUEUE_RECEIVE_FROM_ISR causes such a | ||
|  |  * co-routine to unblock *pxCoRoutineWoken will get set to pdTRUE, otherwise | ||
|  |  * *pxCoRoutineWoken will remain unchanged. | ||
|  |  * | ||
|  |  * @return pdTRUE an item was successfully received from the queue, otherwise | ||
|  |  * pdFALSE. | ||
|  |  * | ||
|  |  * Example usage: | ||
|  |  <pre> | ||
|  |  // A co-routine that posts a character to a queue then blocks for a fixed
 | ||
|  |  // period.  The character is incremented each time.
 | ||
|  |  static void vSendingCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex ) | ||
|  |  { | ||
|  |  // cChar holds its value while this co-routine is blocked and must therefore
 | ||
|  |  // be declared static.
 | ||
|  |  static char cCharToTx = 'a'; | ||
|  |  portBASE_TYPE xResult; | ||
|  | 
 | ||
|  |      // All co-routines must start with a call to crSTART().
 | ||
|  |      crSTART( xHandle ); | ||
|  | 
 | ||
|  |      for( ;; ) | ||
|  |      { | ||
|  |          // Send the next character to the queue.
 | ||
|  |          crQUEUE_SEND( xHandle, xCoRoutineQueue, &cCharToTx, NO_DELAY, &xResult ); | ||
|  | 
 | ||
|  |          if( xResult == pdPASS ) | ||
|  |          { | ||
|  |              // The character was successfully posted to the queue.
 | ||
|  |          } | ||
|  | 		 else | ||
|  | 		 { | ||
|  | 			// Could not post the character to the queue.
 | ||
|  | 		 } | ||
|  | 
 | ||
|  |          // Enable the UART Tx interrupt to cause an interrupt in this
 | ||
|  | 		 // hypothetical UART.  The interrupt will obtain the character
 | ||
|  | 		 // from the queue and send it.
 | ||
|  | 		 ENABLE_RX_INTERRUPT(); | ||
|  | 
 | ||
|  | 		 // Increment to the next character then block for a fixed period.
 | ||
|  | 		 // cCharToTx will maintain its value across the delay as it is
 | ||
|  | 		 // declared static.
 | ||
|  | 		 cCharToTx++; | ||
|  | 		 if( cCharToTx > 'x' ) | ||
|  | 		 { | ||
|  | 			cCharToTx = 'a'; | ||
|  | 		 } | ||
|  | 		 crDELAY( 100 ); | ||
|  |      } | ||
|  | 
 | ||
|  |      // All co-routines must end with a call to crEND().
 | ||
|  |      crEND(); | ||
|  |  } | ||
|  | 
 | ||
|  |  // An ISR that uses a queue to receive characters to send on a UART.
 | ||
|  |  void vUART_ISR( void ) | ||
|  |  { | ||
|  |  char cCharToTx; | ||
|  |  portBASE_TYPE xCRWokenByPost = pdFALSE; | ||
|  | 
 | ||
|  |      while( UART_TX_REG_EMPTY() ) | ||
|  |      { | ||
|  |          // Are there any characters in the queue waiting to be sent?
 | ||
|  | 		 // xCRWokenByPost will automatically be set to pdTRUE if a co-routine
 | ||
|  | 		 // is woken by the post - ensuring that only a single co-routine is
 | ||
|  | 		 // woken no matter how many times we go around this loop.
 | ||
|  |          if( crQUEUE_RECEIVE_FROM_ISR( pxQueue, &cCharToTx, &xCRWokenByPost ) ) | ||
|  | 		 { | ||
|  | 			 SEND_CHARACTER( cCharToTx ); | ||
|  | 		 } | ||
|  |      } | ||
|  |  }</pre> | ||
|  |  * \defgroup crQUEUE_RECEIVE_FROM_ISR crQUEUE_RECEIVE_FROM_ISR | ||
|  |  * \ingroup Tasks | ||
|  |  */ | ||
|  | #define crQUEUE_RECEIVE_FROM_ISR( pxQueue, pvBuffer, pxCoRoutineWoken ) xQueueCRReceiveFromISR( ( pxQueue ), ( pvBuffer ), ( pxCoRoutineWoken ) )
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * This function is intended for internal use by the co-routine macros only. | ||
|  |  * The macro nature of the co-routine implementation requires that the | ||
|  |  * prototype appears here.  The function should not be used by application | ||
|  |  * writers. | ||
|  |  * | ||
|  |  * Removes the current co-routine from its ready list and places it in the | ||
|  |  * appropriate delayed list. | ||
|  |  */ | ||
|  | void vCoRoutineAddToDelayedList( portTickType xTicksToDelay, xList *pxEventList ); | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * This function is intended for internal use by the queue implementation only. | ||
|  |  * The function should not be used by application writers. | ||
|  |  * | ||
|  |  * Removes the highest priority co-routine from the event list and places it in | ||
|  |  * the pending ready list. | ||
|  |  */ | ||
|  | signed portBASE_TYPE xCoRoutineRemoveFromEventList( const xList *pxEventList ); | ||
|  | 
 | ||
|  | #ifdef __cplusplus
 | ||
|  | } | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #endif /* CO_ROUTINE_H */
 |