/* | |
* FreeRTOS Kernel V10.3.1 | |
* Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. | |
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*/ | |
#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 vCoRoutineSchedule() 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 */ |