2 FreeRTOS.org V5.0.2 - Copyright (C) 2003-2008 Richard Barry.
\r
4 This file is part of the FreeRTOS.org distribution.
\r
6 FreeRTOS.org is free software; you can redistribute it and/or modify
\r
7 it under the terms of the GNU General Public License as published by
\r
8 the Free Software Foundation; either version 2 of the License, or
\r
9 (at your option) any later version.
\r
11 FreeRTOS.org is distributed in the hope that it will be useful,
\r
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
\r
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
\r
14 GNU General Public License for more details.
\r
16 You should have received a copy of the GNU General Public License
\r
17 along with FreeRTOS.org; if not, write to the Free Software
\r
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
\r
20 A special exception to the GPL can be applied should you wish to distribute
\r
21 a combined work that includes FreeRTOS.org, without being obliged to provide
\r
22 the source code for any proprietary components. See the licensing section
\r
23 of http://www.FreeRTOS.org for full details of how and when the exception
\r
26 ***************************************************************************
\r
27 ***************************************************************************
\r
29 * SAVE TIME AND MONEY! We can port FreeRTOS.org to your own hardware, *
\r
30 * and even write all or part of your application on your behalf. *
\r
31 * See http://www.OpenRTOS.com for details of the services we provide to *
\r
32 * expedite your project. *
\r
34 ***************************************************************************
\r
35 ***************************************************************************
\r
37 Please ensure to read the configuration and relevant port sections of the
\r
38 online documentation.
\r
40 http://www.FreeRTOS.org - Documentation, latest information, license and
\r
43 http://www.SafeRTOS.com - A version that is certified for use in safety
\r
46 http://www.OpenRTOS.com - Commercial support, development, porting,
\r
47 licensing and training services.
\r
49 #ifndef CO_ROUTINE_H
\r
50 #define CO_ROUTINE_H
\r
58 /* Used to hide the implementation of the co-routine control block. The
\r
59 control block structure however has to be included in the header due to
\r
60 the macro implementation of the co-routine functionality. */
\r
61 typedef void * xCoRoutineHandle;
\r
63 /* Defines the prototype to which co-routine functions must conform. */
\r
64 typedef void (*crCOROUTINE_CODE)( xCoRoutineHandle, unsigned portBASE_TYPE );
\r
66 typedef struct corCoRoutineControlBlock
\r
68 crCOROUTINE_CODE pxCoRoutineFunction;
\r
69 xListItem xGenericListItem; /*< List item used to place the CRCB in ready and blocked queues. */
\r
70 xListItem xEventListItem; /*< List item used to place the CRCB in event lists. */
\r
71 unsigned portBASE_TYPE uxPriority; /*< The priority of the co-routine in relation to other co-routines. */
\r
72 unsigned portBASE_TYPE uxIndex; /*< Used to distinguish between co-routines when multiple co-routines use the same co-routine function. */
\r
73 unsigned portSHORT uxState; /*< Used internally by the co-routine implementation. */
\r
74 } corCRCB; /* Co-routine control block. Note must be identical in size down to uxPriority with tskTCB. */
\r
79 portBASE_TYPE xCoRoutineCreate(
\r
80 crCOROUTINE_CODE pxCoRoutineCode,
\r
81 unsigned portBASE_TYPE uxPriority,
\r
82 unsigned portBASE_TYPE uxIndex
\r
85 * Create a new co-routine and add it to the list of co-routines that are
\r
88 * @param pxCoRoutineCode Pointer to the co-routine function. Co-routine
\r
89 * functions require special syntax - see the co-routine section of the WEB
\r
90 * documentation for more information.
\r
92 * @param uxPriority The priority with respect to other co-routines at which
\r
93 * the co-routine will run.
\r
95 * @param uxIndex Used to distinguish between different co-routines that
\r
96 * execute the same function. See the example below and the co-routine section
\r
97 * of the WEB documentation for further information.
\r
99 * @return pdPASS if the co-routine was successfully created and added to a ready
\r
100 * list, otherwise an error code defined with ProjDefs.h.
\r
104 // Co-routine to be created.
\r
105 void vFlashCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )
\r
107 // Variables in co-routines must be declared static if they must maintain value across a blocking call.
\r
108 // This may not be necessary for const variables.
\r
109 static const char cLedToFlash[ 2 ] = { 5, 6 };
\r
110 static const portTickType xTimeToDelay[ 2 ] = { 200, 400 };
\r
112 // Must start every co-routine with a call to crSTART();
\r
113 crSTART( xHandle );
\r
117 // This co-routine just delays for a fixed period, then toggles
\r
118 // an LED. Two co-routines are created using this function, so
\r
119 // the uxIndex parameter is used to tell the co-routine which
\r
120 // LED to flash and how long to delay. This assumes xQueue has
\r
121 // already been created.
\r
122 vParTestToggleLED( cLedToFlash[ uxIndex ] );
\r
123 crDELAY( xHandle, uxFlashRates[ uxIndex ] );
\r
126 // Must end every co-routine with a call to crEND();
\r
130 // Function that creates two co-routines.
\r
131 void vOtherFunction( void )
\r
133 unsigned char ucParameterToPass;
\r
134 xTaskHandle xHandle;
\r
136 // Create two co-routines at priority 0. The first is given index 0
\r
137 // so (from the code above) toggles LED 5 every 200 ticks. The second
\r
138 // is given index 1 so toggles LED 6 every 400 ticks.
\r
139 for( uxIndex = 0; uxIndex < 2; uxIndex++ )
\r
141 xCoRoutineCreate( vFlashCoRoutine, 0, uxIndex );
\r
145 * \defgroup xCoRoutineCreate xCoRoutineCreate
\r
148 signed portBASE_TYPE xCoRoutineCreate( crCOROUTINE_CODE pxCoRoutineCode, unsigned portBASE_TYPE uxPriority, unsigned portBASE_TYPE uxIndex );
\r
154 void vCoRoutineSchedule( void );</pre>
\r
156 * Run a co-routine.
\r
158 * vCoRoutineSchedule() executes the highest priority co-routine that is able
\r
159 * to run. The co-routine will execute until it either blocks, yields or is
\r
160 * preempted by a task. Co-routines execute cooperatively so one
\r
161 * co-routine cannot be preempted by another, but can be preempted by a task.
\r
163 * If an application comprises of both tasks and co-routines then
\r
164 * vCoRoutineSchedule should be called from the idle task (in an idle task
\r
169 // This idle task hook will schedule a co-routine each time it is called.
\r
170 // The rest of the idle task will execute between co-routine calls.
\r
171 void vApplicationIdleHook( void )
\r
173 vCoRoutineSchedule();
\r
176 // Alternatively, if you do not require any other part of the idle task to
\r
177 // execute, the idle task hook can call vCoRoutineScheduler() within an
\r
179 void vApplicationIdleHook( void )
\r
183 vCoRoutineSchedule();
\r
187 * \defgroup vCoRoutineSchedule vCoRoutineSchedule
\r
190 void vCoRoutineSchedule( void );
\r
195 crSTART( xCoRoutineHandle xHandle );</pre>
\r
197 * This macro MUST always be called at the start of a co-routine function.
\r
201 // Co-routine to be created.
\r
202 void vACoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )
\r
204 // Variables in co-routines must be declared static if they must maintain value across a blocking call.
\r
205 static portLONG ulAVariable;
\r
207 // Must start every co-routine with a call to crSTART();
\r
208 crSTART( xHandle );
\r
212 // Co-routine functionality goes here.
\r
215 // Must end every co-routine with a call to crEND();
\r
218 * \defgroup crSTART crSTART
\r
221 #define crSTART( pxCRCB ) switch( ( ( corCRCB * )pxCRCB )->uxState ) { case 0:
\r
228 * This macro MUST always be called at the end of a co-routine function.
\r
232 // Co-routine to be created.
\r
233 void vACoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )
\r
235 // Variables in co-routines must be declared static if they must maintain value across a blocking call.
\r
236 static portLONG ulAVariable;
\r
238 // Must start every co-routine with a call to crSTART();
\r
239 crSTART( xHandle );
\r
243 // Co-routine functionality goes here.
\r
246 // Must end every co-routine with a call to crEND();
\r
249 * \defgroup crSTART crSTART
\r
255 * These macros are intended for internal use by the co-routine implementation
\r
256 * only. The macros should not be used directly by application writers.
\r
258 #define crSET_STATE0( xHandle ) ( ( corCRCB * )xHandle)->uxState = (__LINE__ * 2); return; case (__LINE__ * 2):
\r
259 #define crSET_STATE1( xHandle ) ( ( corCRCB * )xHandle)->uxState = ((__LINE__ * 2)+1); return; case ((__LINE__ * 2)+1):
\r
264 crDELAY( xCoRoutineHandle xHandle, portTickType xTicksToDelay );</pre>
\r
266 * Delay a co-routine for a fixed period of time.
\r
268 * crDELAY can only be called from the co-routine function itself - not
\r
269 * from within a function called by the co-routine function. This is because
\r
270 * co-routines do not maintain their own stack.
\r
272 * @param xHandle The handle of the co-routine to delay. This is the xHandle
\r
273 * parameter of the co-routine function.
\r
275 * @param xTickToDelay The number of ticks that the co-routine should delay
\r
276 * for. The actual amount of time this equates to is defined by
\r
277 * configTICK_RATE_HZ (set in FreeRTOSConfig.h). The constant portTICK_RATE_MS
\r
278 * can be used to convert ticks to milliseconds.
\r
282 // Co-routine to be created.
\r
283 void vACoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )
\r
285 // Variables in co-routines must be declared static if they must maintain value across a blocking call.
\r
286 // This may not be necessary for const variables.
\r
287 // We are to delay for 200ms.
\r
288 static const xTickType xDelayTime = 200 / portTICK_RATE_MS;
\r
290 // Must start every co-routine with a call to crSTART();
\r
291 crSTART( xHandle );
\r
295 // Delay for 200ms.
\r
296 crDELAY( xHandle, xDelayTime );
\r
298 // Do something here.
\r
301 // Must end every co-routine with a call to crEND();
\r
304 * \defgroup crDELAY crDELAY
\r
307 #define crDELAY( xHandle, xTicksToDelay ) \
\r
308 if( xTicksToDelay > 0 ) \
\r
310 vCoRoutineAddToDelayedList( xTicksToDelay, NULL ); \
\r
312 crSET_STATE0( xHandle );
\r
317 xCoRoutineHandle xHandle,
\r
318 xQueueHandle pxQueue,
\r
319 void *pvItemToQueue,
\r
320 portTickType xTicksToWait,
\r
321 portBASE_TYPE *pxResult
\r
324 * The macro's crQUEUE_SEND() and crQUEUE_RECEIVE() are the co-routine
\r
325 * equivalent to the xQueueSend() and xQueueReceive() functions used by tasks.
\r
327 * crQUEUE_SEND and crQUEUE_RECEIVE can only be used from a co-routine whereas
\r
328 * xQueueSend() and xQueueReceive() can only be used from tasks.
\r
330 * crQUEUE_SEND can only be called from the co-routine function itself - not
\r
331 * from within a function called by the co-routine function. This is because
\r
332 * co-routines do not maintain their own stack.
\r
334 * See the co-routine section of the WEB documentation for information on
\r
335 * passing data between tasks and co-routines and between ISR's and
\r
338 * @param xHandle The handle of the calling co-routine. This is the xHandle
\r
339 * parameter of the co-routine function.
\r
341 * @param pxQueue The handle of the queue on which the data will be posted.
\r
342 * The handle is obtained as the return value when the queue is created using
\r
343 * the xQueueCreate() API function.
\r
345 * @param pvItemToQueue A pointer to the data being posted onto the queue.
\r
346 * The number of bytes of each queued item is specified when the queue is
\r
347 * created. This number of bytes is copied from pvItemToQueue into the queue
\r
350 * @param xTickToDelay The number of ticks that the co-routine should block
\r
351 * to wait for space to become available on the queue, should space not be
\r
352 * available immediately. The actual amount of time this equates to is defined
\r
353 * by configTICK_RATE_HZ (set in FreeRTOSConfig.h). The constant
\r
354 * portTICK_RATE_MS can be used to convert ticks to milliseconds (see example
\r
357 * @param pxResult The variable pointed to by pxResult will be set to pdPASS if
\r
358 * data was successfully posted onto the queue, otherwise it will be set to an
\r
359 * error defined within ProjDefs.h.
\r
363 // Co-routine function that blocks for a fixed period then posts a number onto
\r
365 static void prvCoRoutineFlashTask( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )
\r
367 // Variables in co-routines must be declared static if they must maintain value across a blocking call.
\r
368 static portBASE_TYPE xNumberToPost = 0;
\r
369 static portBASE_TYPE xResult;
\r
371 // Co-routines must begin with a call to crSTART().
\r
372 crSTART( xHandle );
\r
376 // This assumes the queue has already been created.
\r
377 crQUEUE_SEND( xHandle, xCoRoutineQueue, &xNumberToPost, NO_DELAY, &xResult );
\r
379 if( xResult != pdPASS )
\r
381 // The message was not posted!
\r
384 // Increment the number to be posted onto the queue.
\r
387 // Delay for 100 ticks.
\r
388 crDELAY( xHandle, 100 );
\r
391 // Co-routines must end with a call to crEND().
\r
394 * \defgroup crQUEUE_SEND crQUEUE_SEND
\r
397 #define crQUEUE_SEND( xHandle, pxQueue, pvItemToQueue, xTicksToWait, pxResult ) \
\r
399 *pxResult = xQueueCRSend( pxQueue, pvItemToQueue, xTicksToWait ); \
\r
400 if( *pxResult == errQUEUE_BLOCKED ) \
\r
402 crSET_STATE0( xHandle ); \
\r
403 *pxResult = xQueueCRSend( pxQueue, pvItemToQueue, 0 ); \
\r
405 if( *pxResult == errQUEUE_YIELD ) \
\r
407 crSET_STATE1( xHandle ); \
\r
408 *pxResult = pdPASS; \
\r
416 xCoRoutineHandle xHandle,
\r
417 xQueueHandle pxQueue,
\r
419 portTickType xTicksToWait,
\r
420 portBASE_TYPE *pxResult
\r
423 * The macro's crQUEUE_SEND() and crQUEUE_RECEIVE() are the co-routine
\r
424 * equivalent to the xQueueSend() and xQueueReceive() functions used by tasks.
\r
426 * crQUEUE_SEND and crQUEUE_RECEIVE can only be used from a co-routine whereas
\r
427 * xQueueSend() and xQueueReceive() can only be used from tasks.
\r
429 * crQUEUE_RECEIVE can only be called from the co-routine function itself - not
\r
430 * from within a function called by the co-routine function. This is because
\r
431 * co-routines do not maintain their own stack.
\r
433 * See the co-routine section of the WEB documentation for information on
\r
434 * passing data between tasks and co-routines and between ISR's and
\r
437 * @param xHandle The handle of the calling co-routine. This is the xHandle
\r
438 * parameter of the co-routine function.
\r
440 * @param pxQueue The handle of the queue from which the data will be received.
\r
441 * The handle is obtained as the return value when the queue is created using
\r
442 * the xQueueCreate() API function.
\r
444 * @param pvBuffer The buffer into which the received item is to be copied.
\r
445 * The number of bytes of each queued item is specified when the queue is
\r
446 * created. This number of bytes is copied into pvBuffer.
\r
448 * @param xTickToDelay The number of ticks that the co-routine should block
\r
449 * to wait for data to become available from the queue, should data not be
\r
450 * available immediately. The actual amount of time this equates to is defined
\r
451 * by configTICK_RATE_HZ (set in FreeRTOSConfig.h). The constant
\r
452 * portTICK_RATE_MS can be used to convert ticks to milliseconds (see the
\r
453 * crQUEUE_SEND example).
\r
455 * @param pxResult The variable pointed to by pxResult will be set to pdPASS if
\r
456 * data was successfully retrieved from the queue, otherwise it will be set to
\r
457 * an error code as defined within ProjDefs.h.
\r
461 // A co-routine receives the number of an LED to flash from a queue. It
\r
462 // blocks on the queue until the number is received.
\r
463 static void prvCoRoutineFlashWorkTask( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )
\r
465 // Variables in co-routines must be declared static if they must maintain value across a blocking call.
\r
466 static portBASE_TYPE xResult;
\r
467 static unsigned portBASE_TYPE uxLEDToFlash;
\r
469 // All co-routines must start with a call to crSTART().
\r
470 crSTART( xHandle );
\r
474 // Wait for data to become available on the queue.
\r
475 crQUEUE_RECEIVE( xHandle, xCoRoutineQueue, &uxLEDToFlash, portMAX_DELAY, &xResult );
\r
477 if( xResult == pdPASS )
\r
479 // We received the LED to flash - flash it!
\r
480 vParTestToggleLED( uxLEDToFlash );
\r
486 * \defgroup crQUEUE_RECEIVE crQUEUE_RECEIVE
\r
489 #define crQUEUE_RECEIVE( xHandle, pxQueue, pvBuffer, xTicksToWait, pxResult ) \
\r
491 *pxResult = xQueueCRReceive( pxQueue, pvBuffer, xTicksToWait ); \
\r
492 if( *pxResult == errQUEUE_BLOCKED ) \
\r
494 crSET_STATE0( xHandle ); \
\r
495 *pxResult = xQueueCRReceive( pxQueue, pvBuffer, 0 ); \
\r
497 if( *pxResult == errQUEUE_YIELD ) \
\r
499 crSET_STATE1( xHandle ); \
\r
500 *pxResult = pdPASS; \
\r
507 crQUEUE_SEND_FROM_ISR(
\r
508 xQueueHandle pxQueue,
\r
509 void *pvItemToQueue,
\r
510 portBASE_TYPE xCoRoutinePreviouslyWoken
\r
513 * The macro's crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() are the
\r
514 * co-routine equivalent to the xQueueSendFromISR() and xQueueReceiveFromISR()
\r
515 * functions used by tasks.
\r
517 * crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() can only be used to
\r
518 * pass data between a co-routine and and ISR, whereas xQueueSendFromISR() and
\r
519 * xQueueReceiveFromISR() can only be used to pass data between a task and and
\r
522 * crQUEUE_SEND_FROM_ISR can only be called from an ISR to send data to a queue
\r
523 * that is being used from within a co-routine.
\r
525 * See the co-routine section of the WEB documentation for information on
\r
526 * passing data between tasks and co-routines and between ISR's and
\r
529 * @param xQueue The handle to the queue on which the item is to be posted.
\r
531 * @param pvItemToQueue A pointer to the item that is to be placed on the
\r
532 * queue. The size of the items the queue will hold was defined when the
\r
533 * queue was created, so this many bytes will be copied from pvItemToQueue
\r
534 * into the queue storage area.
\r
536 * @param xCoRoutinePreviouslyWoken This is included so an ISR can post onto
\r
537 * the same queue multiple times from a single interrupt. The first call
\r
538 * should always pass in pdFALSE. Subsequent calls should pass in
\r
539 * the value returned from the previous call.
\r
541 * @return pdTRUE if a co-routine was woken by posting onto the queue. This is
\r
542 * used by the ISR to determine if a context switch may be required following
\r
547 // A co-routine that blocks on a queue waiting for characters to be received.
\r
548 static void vReceivingCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )
\r
550 portCHAR cRxedChar;
\r
551 portBASE_TYPE xResult;
\r
553 // All co-routines must start with a call to crSTART().
\r
554 crSTART( xHandle );
\r
558 // Wait for data to become available on the queue. This assumes the
\r
559 // queue xCommsRxQueue has already been created!
\r
560 crQUEUE_RECEIVE( xHandle, xCommsRxQueue, &uxLEDToFlash, portMAX_DELAY, &xResult );
\r
562 // Was a character received?
\r
563 if( xResult == pdPASS )
\r
565 // Process the character here.
\r
569 // All co-routines must end with a call to crEND().
\r
573 // An ISR that uses a queue to send characters received on a serial port to
\r
575 void vUART_ISR( void )
\r
577 portCHAR cRxedChar;
\r
578 portBASE_TYPE xCRWokenByPost = pdFALSE;
\r
580 // We loop around reading characters until there are none left in the UART.
\r
581 while( UART_RX_REG_NOT_EMPTY() )
\r
583 // Obtain the character from the UART.
\r
584 cRxedChar = UART_RX_REG;
\r
586 // Post the character onto a queue. xCRWokenByPost will be pdFALSE
\r
587 // the first time around the loop. If the post causes a co-routine
\r
588 // to be woken (unblocked) then xCRWokenByPost will be set to pdTRUE.
\r
589 // In this manner we can ensure that if more than one co-routine is
\r
590 // blocked on the queue only one is woken by this ISR no matter how
\r
591 // many characters are posted to the queue.
\r
592 xCRWokenByPost = crQUEUE_SEND_FROM_ISR( xCommsRxQueue, &cRxedChar, xCRWokenByPost );
\r
595 * \defgroup crQUEUE_SEND_FROM_ISR crQUEUE_SEND_FROM_ISR
\r
598 #define crQUEUE_SEND_FROM_ISR( pxQueue, pvItemToQueue, xCoRoutinePreviouslyWoken ) xQueueCRSendFromISR( pxQueue, pvItemToQueue, xCoRoutinePreviouslyWoken )
\r
604 crQUEUE_SEND_FROM_ISR(
\r
605 xQueueHandle pxQueue,
\r
607 portBASE_TYPE * pxCoRoutineWoken
\r
610 * The macro's crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() are the
\r
611 * co-routine equivalent to the xQueueSendFromISR() and xQueueReceiveFromISR()
\r
612 * functions used by tasks.
\r
614 * crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() can only be used to
\r
615 * pass data between a co-routine and and ISR, whereas xQueueSendFromISR() and
\r
616 * xQueueReceiveFromISR() can only be used to pass data between a task and and
\r
619 * crQUEUE_RECEIVE_FROM_ISR can only be called from an ISR to receive data
\r
620 * from a queue that is being used from within a co-routine (a co-routine
\r
621 * posted to the queue).
\r
623 * See the co-routine section of the WEB documentation for information on
\r
624 * passing data between tasks and co-routines and between ISR's and
\r
627 * @param xQueue The handle to the queue on which the item is to be posted.
\r
629 * @param pvBuffer A pointer to a buffer into which the received item will be
\r
630 * placed. The size of the items the queue will hold was defined when the
\r
631 * queue was created, so this many bytes will be copied from the queue into
\r
634 * @param pxCoRoutineWoken A co-routine may be blocked waiting for space to become
\r
635 * available on the queue. If crQUEUE_RECEIVE_FROM_ISR causes such a
\r
636 * co-routine to unblock *pxCoRoutineWoken will get set to pdTRUE, otherwise
\r
637 * *pxCoRoutineWoken will remain unchanged.
\r
639 * @return pdTRUE an item was successfully received from the queue, otherwise
\r
644 // A co-routine that posts a character to a queue then blocks for a fixed
\r
645 // period. The character is incremented each time.
\r
646 static void vSendingCoRoutine( xCoRoutineHandle xHandle, unsigned portBASE_TYPE uxIndex )
\r
648 // cChar holds its value while this co-routine is blocked and must therefore
\r
649 // be declared static.
\r
650 static portCHAR cCharToTx = 'a';
\r
651 portBASE_TYPE xResult;
\r
653 // All co-routines must start with a call to crSTART().
\r
654 crSTART( xHandle );
\r
658 // Send the next character to the queue.
\r
659 crQUEUE_SEND( xHandle, xCoRoutineQueue, &cCharToTx, NO_DELAY, &xResult );
\r
661 if( xResult == pdPASS )
\r
663 // The character was successfully posted to the queue.
\r
667 // Could not post the character to the queue.
\r
670 // Enable the UART Tx interrupt to cause an interrupt in this
\r
671 // hypothetical UART. The interrupt will obtain the character
\r
672 // from the queue and send it.
\r
673 ENABLE_RX_INTERRUPT();
\r
675 // Increment to the next character then block for a fixed period.
\r
676 // cCharToTx will maintain its value across the delay as it is
\r
677 // declared static.
\r
679 if( cCharToTx > 'x' )
\r
686 // All co-routines must end with a call to crEND().
\r
690 // An ISR that uses a queue to receive characters to send on a UART.
\r
691 void vUART_ISR( void )
\r
693 portCHAR cCharToTx;
\r
694 portBASE_TYPE xCRWokenByPost = pdFALSE;
\r
696 while( UART_TX_REG_EMPTY() )
\r
698 // Are there any characters in the queue waiting to be sent?
\r
699 // xCRWokenByPost will automatically be set to pdTRUE if a co-routine
\r
700 // is woken by the post - ensuring that only a single co-routine is
\r
701 // woken no matter how many times we go around this loop.
\r
702 if( crQUEUE_RECEIVE_FROM_ISR( pxQueue, &cCharToTx, &xCRWokenByPost ) )
\r
704 SEND_CHARACTER( cCharToTx );
\r
708 * \defgroup crQUEUE_RECEIVE_FROM_ISR crQUEUE_RECEIVE_FROM_ISR
\r
711 #define crQUEUE_RECEIVE_FROM_ISR( pxQueue, pvBuffer, pxCoRoutineWoken ) xQueueCRReceiveFromISR( pxQueue, pvBuffer, pxCoRoutineWoken )
\r
714 * This function is intended for internal use by the co-routine macros only.
\r
715 * The macro nature of the co-routine implementation requires that the
\r
716 * prototype appears here. The function should not be used by application
\r
719 * Removes the current co-routine from its ready list and places it in the
\r
720 * appropriate delayed list.
\r
722 void vCoRoutineAddToDelayedList( portTickType xTicksToDelay, xList *pxEventList );
\r
725 * This function is intended for internal use by the queue implementation only.
\r
726 * The function should not be used by application writers.
\r
728 * Removes the highest priority co-routine from the event list and places it in
\r
729 * the pending ready list.
\r
731 signed portBASE_TYPE xCoRoutineRemoveFromEventList( const xList *pxEventList );
\r
737 #endif /* CO_ROUTINE_H */
\r