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Diffstat (limited to 'freertos/include/croutine.h')
| -rw-r--r-- | freertos/include/croutine.h | 1482 |
1 files changed, 720 insertions, 762 deletions
diff --git a/freertos/include/croutine.h b/freertos/include/croutine.h index 4f003a0..32b742b 100644 --- a/freertos/include/croutine.h +++ b/freertos/include/croutine.h @@ -1,762 +1,720 @@ -/* - 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 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 * CoRoutineHandle_t; - -/* Defines the prototype to which co-routine functions must conform. */ -typedef void (*crCOROUTINE_CODE)( CoRoutineHandle_t, UBaseType_t ); - -typedef struct corCoRoutineControlBlock -{ - crCOROUTINE_CODE pxCoRoutineFunction; - ListItem_t xGenericListItem; /*< List item used to place the CRCB in ready and blocked queues. */ - ListItem_t xEventListItem; /*< List item used to place the CRCB in event lists. */ - UBaseType_t uxPriority; /*< The priority of the co-routine in relation to other co-routines. */ - UBaseType_t uxIndex; /*< Used to distinguish between co-routines when multiple co-routines use the same co-routine function. */ - uint16_t uxState; /*< Used internally by the co-routine implementation. */ -} CRCB_t; /* Co-routine control block. Note must be identical in size down to uxPriority with TCB_t. */ - -/** - * croutine. h - *<pre> - BaseType_t xCoRoutineCreate( - crCOROUTINE_CODE pxCoRoutineCode, - UBaseType_t uxPriority, - UBaseType_t 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( CoRoutineHandle_t xHandle, UBaseType_t 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 TickType_t 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 int32_t 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 ) - { - uint8_t ucParameterToPass; - TaskHandle_t 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 - */ -BaseType_t xCoRoutineCreate( crCOROUTINE_CODE pxCoRoutineCode, UBaseType_t uxPriority, UBaseType_t 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( CoRoutineHandle_t 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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) - { - // Variables in co-routines must be declared static if they must maintain value across a blocking call. - static int32_t 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( ( ( CRCB_t * )( 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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) - { - // Variables in co-routines must be declared static if they must maintain value across a blocking call. - static int32_t 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 ) ( ( CRCB_t * )( xHandle ) )->uxState = (__LINE__ * 2); return; case (__LINE__ * 2): -#define crSET_STATE1( xHandle ) ( ( CRCB_t * )( xHandle ) )->uxState = ((__LINE__ * 2)+1); return; case ((__LINE__ * 2)+1): - -/** - * croutine. h - *<pre> - crDELAY( CoRoutineHandle_t xHandle, TickType_t 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_PERIOD_MS - * can be used to convert ticks to milliseconds. - * - * Example usage: - <pre> - // Co-routine to be created. - void vACoRoutine( CoRoutineHandle_t xHandle, UBaseType_t 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_PERIOD_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( - CoRoutineHandle_t xHandle, - QueueHandle_t pxQueue, - void *pvItemToQueue, - TickType_t xTicksToWait, - BaseType_t *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_PERIOD_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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) - { - // Variables in co-routines must be declared static if they must maintain value across a blocking call. - static BaseType_t xNumberToPost = 0; - static BaseType_t 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( - CoRoutineHandle_t xHandle, - QueueHandle_t pxQueue, - void *pvBuffer, - TickType_t xTicksToWait, - BaseType_t *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_PERIOD_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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) - { - // Variables in co-routines must be declared static if they must maintain value across a blocking call. - static BaseType_t xResult; - static UBaseType_t 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( - QueueHandle_t pxQueue, - void *pvItemToQueue, - BaseType_t 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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) - { - char cRxedChar; - BaseType_t 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; - BaseType_t 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( - QueueHandle_t pxQueue, - void *pvBuffer, - BaseType_t * 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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) - { - // cChar holds its value while this co-routine is blocked and must therefore - // be declared static. - static char cCharToTx = 'a'; - BaseType_t 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; - BaseType_t 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( TickType_t xTicksToDelay, List_t *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. - */ -BaseType_t xCoRoutineRemoveFromEventList( const List_t *pxEventList ); - -#ifdef __cplusplus -} -#endif - -#endif /* CO_ROUTINE_H */ +/*
+ * FreeRTOS Kernel V10.1.1
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://www.FreeRTOS.org
+ * http://aws.amazon.com/freertos
+ *
+ * 1 tab == 4 spaces!
+ */
+
+#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 * CoRoutineHandle_t;
+
+/* Defines the prototype to which co-routine functions must conform. */
+typedef void (*crCOROUTINE_CODE)( CoRoutineHandle_t, UBaseType_t );
+
+typedef struct corCoRoutineControlBlock
+{
+ crCOROUTINE_CODE pxCoRoutineFunction;
+ ListItem_t xGenericListItem; /*< List item used to place the CRCB in ready and blocked queues. */
+ ListItem_t xEventListItem; /*< List item used to place the CRCB in event lists. */
+ UBaseType_t uxPriority; /*< The priority of the co-routine in relation to other co-routines. */
+ UBaseType_t uxIndex; /*< Used to distinguish between co-routines when multiple co-routines use the same co-routine function. */
+ uint16_t uxState; /*< Used internally by the co-routine implementation. */
+} CRCB_t; /* Co-routine control block. Note must be identical in size down to uxPriority with TCB_t. */
+
+/**
+ * croutine. h
+ *<pre>
+ BaseType_t xCoRoutineCreate(
+ crCOROUTINE_CODE pxCoRoutineCode,
+ UBaseType_t uxPriority,
+ UBaseType_t 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( CoRoutineHandle_t xHandle, UBaseType_t 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 TickType_t 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 int32_t 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 )
+ {
+ uint8_t ucParameterToPass;
+ TaskHandle_t 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
+ */
+BaseType_t xCoRoutineCreate( crCOROUTINE_CODE pxCoRoutineCode, UBaseType_t uxPriority, UBaseType_t 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( CoRoutineHandle_t 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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
+ {
+ // Variables in co-routines must be declared static if they must maintain value across a blocking call.
+ static int32_t 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( ( ( CRCB_t * )( 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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
+ {
+ // Variables in co-routines must be declared static if they must maintain value across a blocking call.
+ static int32_t 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 ) ( ( CRCB_t * )( xHandle ) )->uxState = (__LINE__ * 2); return; case (__LINE__ * 2):
+#define crSET_STATE1( xHandle ) ( ( CRCB_t * )( xHandle ) )->uxState = ((__LINE__ * 2)+1); return; case ((__LINE__ * 2)+1):
+
+/**
+ * croutine. h
+ *<pre>
+ crDELAY( CoRoutineHandle_t xHandle, TickType_t 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_PERIOD_MS
+ * can be used to convert ticks to milliseconds.
+ *
+ * Example usage:
+ <pre>
+ // Co-routine to be created.
+ void vACoRoutine( CoRoutineHandle_t xHandle, UBaseType_t 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_PERIOD_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(
+ CoRoutineHandle_t xHandle,
+ QueueHandle_t pxQueue,
+ void *pvItemToQueue,
+ TickType_t xTicksToWait,
+ BaseType_t *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_PERIOD_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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
+ {
+ // Variables in co-routines must be declared static if they must maintain value across a blocking call.
+ static BaseType_t xNumberToPost = 0;
+ static BaseType_t 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(
+ CoRoutineHandle_t xHandle,
+ QueueHandle_t pxQueue,
+ void *pvBuffer,
+ TickType_t xTicksToWait,
+ BaseType_t *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_PERIOD_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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
+ {
+ // Variables in co-routines must be declared static if they must maintain value across a blocking call.
+ static BaseType_t xResult;
+ static UBaseType_t 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(
+ QueueHandle_t pxQueue,
+ void *pvItemToQueue,
+ BaseType_t 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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
+ {
+ char cRxedChar;
+ BaseType_t 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;
+ BaseType_t 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(
+ QueueHandle_t pxQueue,
+ void *pvBuffer,
+ BaseType_t * 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( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
+ {
+ // cChar holds its value while this co-routine is blocked and must therefore
+ // be declared static.
+ static char cCharToTx = 'a';
+ BaseType_t 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;
+ BaseType_t 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( TickType_t xTicksToDelay, List_t *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.
+ */
+BaseType_t xCoRoutineRemoveFromEventList( const List_t *pxEventList );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* CO_ROUTINE_H */
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