1 /* 2 FreeRTOS V9.0.0 - Copyright (C) 2016 Real Time Engineers Ltd. 3 All rights reserved 4 5 VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. 6 7 This file is part of the FreeRTOS distribution. 8 9 FreeRTOS is free software; you can redistribute it and/or modify it under 10 the terms of the GNU General Public License (version 2) as published by the 11 Free Software Foundation >>>> AND MODIFIED BY <<<< the FreeRTOS exception. 12 13 *************************************************************************** 14 >>! NOTE: The modification to the GPL is included to allow you to !<< 15 >>! distribute a combined work that includes FreeRTOS without being !<< 16 >>! obliged to provide the source code for proprietary components !<< 17 >>! outside of the FreeRTOS kernel. !<< 18 *************************************************************************** 19 20 FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY 21 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 22 FOR A PARTICULAR PURPOSE. Full license text is available on the following 23 link: http://www.freertos.org/a00114.html 24 25 *************************************************************************** 26 * * 27 * FreeRTOS provides completely free yet professionally developed, * 28 * robust, strictly quality controlled, supported, and cross * 29 * platform software that is more than just the market leader, it * 30 * is the industry's de facto standard. * 31 * * 32 * Help yourself get started quickly while simultaneously helping * 33 * to support the FreeRTOS project by purchasing a FreeRTOS * 34 * tutorial book, reference manual, or both: * 35 * http://www.FreeRTOS.org/Documentation * 36 * * 37 *************************************************************************** 38 39 http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading 40 the FAQ page "My application does not run, what could be wrong?". Have you 41 defined configASSERT()? 42 43 http://www.FreeRTOS.org/support - In return for receiving this top quality 44 embedded software for free we request you assist our global community by 45 participating in the support forum. 46 47 http://www.FreeRTOS.org/training - Investing in training allows your team to 48 be as productive as possible as early as possible. Now you can receive 49 FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers 50 Ltd, and the world's leading authority on the world's leading RTOS. 51 52 http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, 53 including FreeRTOS+Trace - an indispensable productivity tool, a DOS 54 compatible FAT file system, and our tiny thread aware UDP/IP stack. 55 56 http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate. 57 Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS. 58 59 http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High 60 Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS 61 licenses offer ticketed support, indemnification and commercial middleware. 62 63 http://www.SafeRTOS.com - High Integrity Systems also provide a safety 64 engineered and independently SIL3 certified version for use in safety and 65 mission critical applications that require provable dependability. 66 67 1 tab == 4 spaces! 68 */ 69 70 #ifndef CO_ROUTINE_H 71 #define CO_ROUTINE_H 72 73 #ifndef INC_FREERTOS_H 74 #error "include FreeRTOS.h must appear in source files before include croutine.h" 75 #endif 76 77 #include "list.h" 78 79 #ifdef __cplusplus 80 extern "C" { 81 #endif 82 83 /* Used to hide the implementation of the co-routine control block. The 84 control block structure however has to be included in the header due to 85 the macro implementation of the co-routine functionality. */ 86 typedef void * CoRoutineHandle_t; 87 88 /* Defines the prototype to which co-routine functions must conform. */ 89 typedef void (*crCOROUTINE_CODE)( CoRoutineHandle_t, UBaseType_t ); 90 91 typedef struct corCoRoutineControlBlock 92 { 93 crCOROUTINE_CODE pxCoRoutineFunction; 94 ListItem_t xGenericListItem; /*< List item used to place the CRCB in ready and blocked queues. */ 95 ListItem_t xEventListItem; /*< List item used to place the CRCB in event lists. */ 96 UBaseType_t uxPriority; /*< The priority of the co-routine in relation to other co-routines. */ 97 UBaseType_t uxIndex; /*< Used to distinguish between co-routines when multiple co-routines use the same co-routine function. */ 98 uint16_t uxState; /*< Used internally by the co-routine implementation. */ 99 } CRCB_t; /* Co-routine control block. Note must be identical in size down to uxPriority with TCB_t. */ 100 101 /** 102 * croutine. h 103 *<pre> 104 BaseType_t xCoRoutineCreate( 105 crCOROUTINE_CODE pxCoRoutineCode, 106 UBaseType_t uxPriority, 107 UBaseType_t uxIndex 108 );</pre> 109 * 110 * Create a new co-routine and add it to the list of co-routines that are 111 * ready to run. 112 * 113 * @param pxCoRoutineCode Pointer to the co-routine function. Co-routine 114 * functions require special syntax - see the co-routine section of the WEB 115 * documentation for more information. 116 * 117 * @param uxPriority The priority with respect to other co-routines at which 118 * the co-routine will run. 119 * 120 * @param uxIndex Used to distinguish between different co-routines that 121 * execute the same function. See the example below and the co-routine section 122 * of the WEB documentation for further information. 123 * 124 * @return pdPASS if the co-routine was successfully created and added to a ready 125 * list, otherwise an error code defined with ProjDefs.h. 126 * 127 * Example usage: 128 <pre> 129 // Co-routine to be created. 130 void vFlashCoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) 131 { 132 // Variables in co-routines must be declared static if they must maintain value across a blocking call. 133 // This may not be necessary for const variables. 134 static const char cLedToFlash[ 2 ] = { 5, 6 }; 135 static const TickType_t uxFlashRates[ 2 ] = { 200, 400 }; 136 137 // Must start every co-routine with a call to crSTART(); 138 crSTART( xHandle ); 139 140 for( ;; ) 141 { 142 // This co-routine just delays for a fixed period, then toggles 143 // an LED. Two co-routines are created using this function, so 144 // the uxIndex parameter is used to tell the co-routine which 145 // LED to flash and how int32_t to delay. This assumes xQueue has 146 // already been created. 147 vParTestToggleLED( cLedToFlash[ uxIndex ] ); 148 crDELAY( xHandle, uxFlashRates[ uxIndex ] ); 149 } 150 151 // Must end every co-routine with a call to crEND(); 152 crEND(); 153 } 154 155 // Function that creates two co-routines. 156 void vOtherFunction( void ) 157 { 158 uint8_t ucParameterToPass; 159 TaskHandle_t xHandle; 160 161 // Create two co-routines at priority 0. The first is given index 0 162 // so (from the code above) toggles LED 5 every 200 ticks. The second 163 // is given index 1 so toggles LED 6 every 400 ticks. 164 for( uxIndex = 0; uxIndex < 2; uxIndex++ ) 165 { 166 xCoRoutineCreate( vFlashCoRoutine, 0, uxIndex ); 167 } 168 } 169 </pre> 170 * \defgroup xCoRoutineCreate xCoRoutineCreate 171 * \ingroup Tasks 172 */ 173 BaseType_t xCoRoutineCreate( crCOROUTINE_CODE pxCoRoutineCode, UBaseType_t uxPriority, UBaseType_t uxIndex ); 174 175 176 /** 177 * croutine. h 178 *<pre> 179 void vCoRoutineSchedule( void );</pre> 180 * 181 * Run a co-routine. 182 * 183 * vCoRoutineSchedule() executes the highest priority co-routine that is able 184 * to run. The co-routine will execute until it either blocks, yields or is 185 * preempted by a task. Co-routines execute cooperatively so one 186 * co-routine cannot be preempted by another, but can be preempted by a task. 187 * 188 * If an application comprises of both tasks and co-routines then 189 * vCoRoutineSchedule should be called from the idle task (in an idle task 190 * hook). 191 * 192 * Example usage: 193 <pre> 194 // This idle task hook will schedule a co-routine each time it is called. 195 // The rest of the idle task will execute between co-routine calls. 196 void vApplicationIdleHook( void ) 197 { 198 vCoRoutineSchedule(); 199 } 200 201 // Alternatively, if you do not require any other part of the idle task to 202 // execute, the idle task hook can call vCoRoutineScheduler() within an 203 // infinite loop. 204 void vApplicationIdleHook( void ) 205 { 206 for( ;; ) 207 { 208 vCoRoutineSchedule(); 209 } 210 } 211 </pre> 212 * \defgroup vCoRoutineSchedule vCoRoutineSchedule 213 * \ingroup Tasks 214 */ 215 void vCoRoutineSchedule( void ); 216 217 /** 218 * croutine. h 219 * <pre> 220 crSTART( CoRoutineHandle_t xHandle );</pre> 221 * 222 * This macro MUST always be called at the start of a co-routine function. 223 * 224 * Example usage: 225 <pre> 226 // Co-routine to be created. 227 void vACoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) 228 { 229 // Variables in co-routines must be declared static if they must maintain value across a blocking call. 230 static int32_t ulAVariable; 231 232 // Must start every co-routine with a call to crSTART(); 233 crSTART( xHandle ); 234 235 for( ;; ) 236 { 237 // Co-routine functionality goes here. 238 } 239 240 // Must end every co-routine with a call to crEND(); 241 crEND(); 242 }</pre> 243 * \defgroup crSTART crSTART 244 * \ingroup Tasks 245 */ 246 #define crSTART( pxCRCB ) switch( ( ( CRCB_t * )( pxCRCB ) )->uxState ) { case 0: 247 248 /** 249 * croutine. h 250 * <pre> 251 crEND();</pre> 252 * 253 * This macro MUST always be called at the end of a co-routine function. 254 * 255 * Example usage: 256 <pre> 257 // Co-routine to be created. 258 void vACoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) 259 { 260 // Variables in co-routines must be declared static if they must maintain value across a blocking call. 261 static int32_t ulAVariable; 262 263 // Must start every co-routine with a call to crSTART(); 264 crSTART( xHandle ); 265 266 for( ;; ) 267 { 268 // Co-routine functionality goes here. 269 } 270 271 // Must end every co-routine with a call to crEND(); 272 crEND(); 273 }</pre> 274 * \defgroup crSTART crSTART 275 * \ingroup Tasks 276 */ 277 #define crEND() } 278 279 /* 280 * These macros are intended for internal use by the co-routine implementation 281 * only. The macros should not be used directly by application writers. 282 */ 283 #define crSET_STATE0( xHandle ) ( ( CRCB_t * )( xHandle ) )->uxState = (__LINE__ * 2); return; case (__LINE__ * 2): 284 #define crSET_STATE1( xHandle ) ( ( CRCB_t * )( xHandle ) )->uxState = ((__LINE__ * 2)+1); return; case ((__LINE__ * 2)+1): 285 286 /** 287 * croutine. h 288 *<pre> 289 crDELAY( CoRoutineHandle_t xHandle, TickType_t xTicksToDelay );</pre> 290 * 291 * Delay a co-routine for a fixed period of time. 292 * 293 * crDELAY can only be called from the co-routine function itself - not 294 * from within a function called by the co-routine function. This is because 295 * co-routines do not maintain their own stack. 296 * 297 * @param xHandle The handle of the co-routine to delay. This is the xHandle 298 * parameter of the co-routine function. 299 * 300 * @param xTickToDelay The number of ticks that the co-routine should delay 301 * for. The actual amount of time this equates to is defined by 302 * configTICK_RATE_HZ (set in FreeRTOSConfig.h). The constant portTICK_PERIOD_MS 303 * can be used to convert ticks to milliseconds. 304 * 305 * Example usage: 306 <pre> 307 // Co-routine to be created. 308 void vACoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) 309 { 310 // Variables in co-routines must be declared static if they must maintain value across a blocking call. 311 // This may not be necessary for const variables. 312 // We are to delay for 200ms. 313 static const xTickType xDelayTime = 200 / portTICK_PERIOD_MS; 314 315 // Must start every co-routine with a call to crSTART(); 316 crSTART( xHandle ); 317 318 for( ;; ) 319 { 320 // Delay for 200ms. 321 crDELAY( xHandle, xDelayTime ); 322 323 // Do something here. 324 } 325 326 // Must end every co-routine with a call to crEND(); 327 crEND(); 328 }</pre> 329 * \defgroup crDELAY crDELAY 330 * \ingroup Tasks 331 */ 332 #define crDELAY( xHandle, xTicksToDelay ) \ 333 if( ( xTicksToDelay ) > 0 ) \ 334 { \ 335 vCoRoutineAddToDelayedList( ( xTicksToDelay ), NULL ); \ 336 } \ 337 crSET_STATE0( ( xHandle ) ); 338 339 /** 340 * <pre> 341 crQUEUE_SEND( 342 CoRoutineHandle_t xHandle, 343 QueueHandle_t pxQueue, 344 void *pvItemToQueue, 345 TickType_t xTicksToWait, 346 BaseType_t *pxResult 347 )</pre> 348 * 349 * The macro's crQUEUE_SEND() and crQUEUE_RECEIVE() are the co-routine 350 * equivalent to the xQueueSend() and xQueueReceive() functions used by tasks. 351 * 352 * crQUEUE_SEND and crQUEUE_RECEIVE can only be used from a co-routine whereas 353 * xQueueSend() and xQueueReceive() can only be used from tasks. 354 * 355 * crQUEUE_SEND can only be called from the co-routine function itself - not 356 * from within a function called by the co-routine function. This is because 357 * co-routines do not maintain their own stack. 358 * 359 * See the co-routine section of the WEB documentation for information on 360 * passing data between tasks and co-routines and between ISR's and 361 * co-routines. 362 * 363 * @param xHandle The handle of the calling co-routine. This is the xHandle 364 * parameter of the co-routine function. 365 * 366 * @param pxQueue The handle of the queue on which the data will be posted. 367 * The handle is obtained as the return value when the queue is created using 368 * the xQueueCreate() API function. 369 * 370 * @param pvItemToQueue A pointer to the data being posted onto the queue. 371 * The number of bytes of each queued item is specified when the queue is 372 * created. This number of bytes is copied from pvItemToQueue into the queue 373 * itself. 374 * 375 * @param xTickToDelay The number of ticks that the co-routine should block 376 * to wait for space to become available on the queue, should space not be 377 * available immediately. The actual amount of time this equates to is defined 378 * by configTICK_RATE_HZ (set in FreeRTOSConfig.h). The constant 379 * portTICK_PERIOD_MS can be used to convert ticks to milliseconds (see example 380 * below). 381 * 382 * @param pxResult The variable pointed to by pxResult will be set to pdPASS if 383 * data was successfully posted onto the queue, otherwise it will be set to an 384 * error defined within ProjDefs.h. 385 * 386 * Example usage: 387 <pre> 388 // Co-routine function that blocks for a fixed period then posts a number onto 389 // a queue. 390 static void prvCoRoutineFlashTask( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) 391 { 392 // Variables in co-routines must be declared static if they must maintain value across a blocking call. 393 static BaseType_t xNumberToPost = 0; 394 static BaseType_t xResult; 395 396 // Co-routines must begin with a call to crSTART(). 397 crSTART( xHandle ); 398 399 for( ;; ) 400 { 401 // This assumes the queue has already been created. 402 crQUEUE_SEND( xHandle, xCoRoutineQueue, &xNumberToPost, NO_DELAY, &xResult ); 403 404 if( xResult != pdPASS ) 405 { 406 // The message was not posted! 407 } 408 409 // Increment the number to be posted onto the queue. 410 xNumberToPost++; 411 412 // Delay for 100 ticks. 413 crDELAY( xHandle, 100 ); 414 } 415 416 // Co-routines must end with a call to crEND(). 417 crEND(); 418 }</pre> 419 * \defgroup crQUEUE_SEND crQUEUE_SEND 420 * \ingroup Tasks 421 */ 422 #define crQUEUE_SEND( xHandle, pxQueue, pvItemToQueue, xTicksToWait, pxResult ) \ 423 { \ 424 *( pxResult ) = xQueueCRSend( ( pxQueue) , ( pvItemToQueue) , ( xTicksToWait ) ); \ 425 if( *( pxResult ) == errQUEUE_BLOCKED ) \ 426 { \ 427 crSET_STATE0( ( xHandle ) ); \ 428 *pxResult = xQueueCRSend( ( pxQueue ), ( pvItemToQueue ), 0 ); \ 429 } \ 430 if( *pxResult == errQUEUE_YIELD ) \ 431 { \ 432 crSET_STATE1( ( xHandle ) ); \ 433 *pxResult = pdPASS; \ 434 } \ 435 } 436 437 /** 438 * croutine. h 439 * <pre> 440 crQUEUE_RECEIVE( 441 CoRoutineHandle_t xHandle, 442 QueueHandle_t pxQueue, 443 void *pvBuffer, 444 TickType_t xTicksToWait, 445 BaseType_t *pxResult 446 )</pre> 447 * 448 * The macro's crQUEUE_SEND() and crQUEUE_RECEIVE() are the co-routine 449 * equivalent to the xQueueSend() and xQueueReceive() functions used by tasks. 450 * 451 * crQUEUE_SEND and crQUEUE_RECEIVE can only be used from a co-routine whereas 452 * xQueueSend() and xQueueReceive() can only be used from tasks. 453 * 454 * crQUEUE_RECEIVE can only be called from the co-routine function itself - not 455 * from within a function called by the co-routine function. This is because 456 * co-routines do not maintain their own stack. 457 * 458 * See the co-routine section of the WEB documentation for information on 459 * passing data between tasks and co-routines and between ISR's and 460 * co-routines. 461 * 462 * @param xHandle The handle of the calling co-routine. This is the xHandle 463 * parameter of the co-routine function. 464 * 465 * @param pxQueue The handle of the queue from which the data will be received. 466 * The handle is obtained as the return value when the queue is created using 467 * the xQueueCreate() API function. 468 * 469 * @param pvBuffer The buffer into which the received item is to be copied. 470 * The number of bytes of each queued item is specified when the queue is 471 * created. This number of bytes is copied into pvBuffer. 472 * 473 * @param xTickToDelay The number of ticks that the co-routine should block 474 * to wait for data to become available from the queue, should data not be 475 * available immediately. The actual amount of time this equates to is defined 476 * by configTICK_RATE_HZ (set in FreeRTOSConfig.h). The constant 477 * portTICK_PERIOD_MS can be used to convert ticks to milliseconds (see the 478 * crQUEUE_SEND example). 479 * 480 * @param pxResult The variable pointed to by pxResult will be set to pdPASS if 481 * data was successfully retrieved from the queue, otherwise it will be set to 482 * an error code as defined within ProjDefs.h. 483 * 484 * Example usage: 485 <pre> 486 // A co-routine receives the number of an LED to flash from a queue. It 487 // blocks on the queue until the number is received. 488 static void prvCoRoutineFlashWorkTask( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) 489 { 490 // Variables in co-routines must be declared static if they must maintain value across a blocking call. 491 static BaseType_t xResult; 492 static UBaseType_t uxLEDToFlash; 493 494 // All co-routines must start with a call to crSTART(). 495 crSTART( xHandle ); 496 497 for( ;; ) 498 { 499 // Wait for data to become available on the queue. 500 crQUEUE_RECEIVE( xHandle, xCoRoutineQueue, &uxLEDToFlash, portMAX_DELAY, &xResult ); 501 502 if( xResult == pdPASS ) 503 { 504 // We received the LED to flash - flash it! 505 vParTestToggleLED( uxLEDToFlash ); 506 } 507 } 508 509 crEND(); 510 }</pre> 511 * \defgroup crQUEUE_RECEIVE crQUEUE_RECEIVE 512 * \ingroup Tasks 513 */ 514 #define crQUEUE_RECEIVE( xHandle, pxQueue, pvBuffer, xTicksToWait, pxResult ) \ 515 { \ 516 *( pxResult ) = xQueueCRReceive( ( pxQueue) , ( pvBuffer ), ( xTicksToWait ) ); \ 517 if( *( pxResult ) == errQUEUE_BLOCKED ) \ 518 { \ 519 crSET_STATE0( ( xHandle ) ); \ 520 *( pxResult ) = xQueueCRReceive( ( pxQueue) , ( pvBuffer ), 0 ); \ 521 } \ 522 if( *( pxResult ) == errQUEUE_YIELD ) \ 523 { \ 524 crSET_STATE1( ( xHandle ) ); \ 525 *( pxResult ) = pdPASS; \ 526 } \ 527 } 528 529 /** 530 * croutine. h 531 * <pre> 532 crQUEUE_SEND_FROM_ISR( 533 QueueHandle_t pxQueue, 534 void *pvItemToQueue, 535 BaseType_t xCoRoutinePreviouslyWoken 536 )</pre> 537 * 538 * The macro's crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() are the 539 * co-routine equivalent to the xQueueSendFromISR() and xQueueReceiveFromISR() 540 * functions used by tasks. 541 * 542 * crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() can only be used to 543 * pass data between a co-routine and and ISR, whereas xQueueSendFromISR() and 544 * xQueueReceiveFromISR() can only be used to pass data between a task and and 545 * ISR. 546 * 547 * crQUEUE_SEND_FROM_ISR can only be called from an ISR to send data to a queue 548 * that is being used from within a co-routine. 549 * 550 * See the co-routine section of the WEB documentation for information on 551 * passing data between tasks and co-routines and between ISR's and 552 * co-routines. 553 * 554 * @param xQueue The handle to the queue on which the item is to be posted. 555 * 556 * @param pvItemToQueue A pointer to the item that is to be placed on the 557 * queue. The size of the items the queue will hold was defined when the 558 * queue was created, so this many bytes will be copied from pvItemToQueue 559 * into the queue storage area. 560 * 561 * @param xCoRoutinePreviouslyWoken This is included so an ISR can post onto 562 * the same queue multiple times from a single interrupt. The first call 563 * should always pass in pdFALSE. Subsequent calls should pass in 564 * the value returned from the previous call. 565 * 566 * @return pdTRUE if a co-routine was woken by posting onto the queue. This is 567 * used by the ISR to determine if a context switch may be required following 568 * the ISR. 569 * 570 * Example usage: 571 <pre> 572 // A co-routine that blocks on a queue waiting for characters to be received. 573 static void vReceivingCoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) 574 { 575 char cRxedChar; 576 BaseType_t xResult; 577 578 // All co-routines must start with a call to crSTART(). 579 crSTART( xHandle ); 580 581 for( ;; ) 582 { 583 // Wait for data to become available on the queue. This assumes the 584 // queue xCommsRxQueue has already been created! 585 crQUEUE_RECEIVE( xHandle, xCommsRxQueue, &uxLEDToFlash, portMAX_DELAY, &xResult ); 586 587 // Was a character received? 588 if( xResult == pdPASS ) 589 { 590 // Process the character here. 591 } 592 } 593 594 // All co-routines must end with a call to crEND(). 595 crEND(); 596 } 597 598 // An ISR that uses a queue to send characters received on a serial port to 599 // a co-routine. 600 void vUART_ISR( void ) 601 { 602 char cRxedChar; 603 BaseType_t xCRWokenByPost = pdFALSE; 604 605 // We loop around reading characters until there are none left in the UART. 606 while( UART_RX_REG_NOT_EMPTY() ) 607 { 608 // Obtain the character from the UART. 609 cRxedChar = UART_RX_REG; 610 611 // Post the character onto a queue. xCRWokenByPost will be pdFALSE 612 // the first time around the loop. If the post causes a co-routine 613 // to be woken (unblocked) then xCRWokenByPost will be set to pdTRUE. 614 // In this manner we can ensure that if more than one co-routine is 615 // blocked on the queue only one is woken by this ISR no matter how 616 // many characters are posted to the queue. 617 xCRWokenByPost = crQUEUE_SEND_FROM_ISR( xCommsRxQueue, &cRxedChar, xCRWokenByPost ); 618 } 619 }</pre> 620 * \defgroup crQUEUE_SEND_FROM_ISR crQUEUE_SEND_FROM_ISR 621 * \ingroup Tasks 622 */ 623 #define crQUEUE_SEND_FROM_ISR( pxQueue, pvItemToQueue, xCoRoutinePreviouslyWoken ) xQueueCRSendFromISR( ( pxQueue ), ( pvItemToQueue ), ( xCoRoutinePreviouslyWoken ) ) 624 625 626 /** 627 * croutine. h 628 * <pre> 629 crQUEUE_SEND_FROM_ISR( 630 QueueHandle_t pxQueue, 631 void *pvBuffer, 632 BaseType_t * pxCoRoutineWoken 633 )</pre> 634 * 635 * The macro's crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() are the 636 * co-routine equivalent to the xQueueSendFromISR() and xQueueReceiveFromISR() 637 * functions used by tasks. 638 * 639 * crQUEUE_SEND_FROM_ISR() and crQUEUE_RECEIVE_FROM_ISR() can only be used to 640 * pass data between a co-routine and and ISR, whereas xQueueSendFromISR() and 641 * xQueueReceiveFromISR() can only be used to pass data between a task and and 642 * ISR. 643 * 644 * crQUEUE_RECEIVE_FROM_ISR can only be called from an ISR to receive data 645 * from a queue that is being used from within a co-routine (a co-routine 646 * posted to the queue). 647 * 648 * See the co-routine section of the WEB documentation for information on 649 * passing data between tasks and co-routines and between ISR's and 650 * co-routines. 651 * 652 * @param xQueue The handle to the queue on which the item is to be posted. 653 * 654 * @param pvBuffer A pointer to a buffer into which the received item will be 655 * placed. The size of the items the queue will hold was defined when the 656 * queue was created, so this many bytes will be copied from the queue into 657 * pvBuffer. 658 * 659 * @param pxCoRoutineWoken A co-routine may be blocked waiting for space to become 660 * available on the queue. If crQUEUE_RECEIVE_FROM_ISR causes such a 661 * co-routine to unblock *pxCoRoutineWoken will get set to pdTRUE, otherwise 662 * *pxCoRoutineWoken will remain unchanged. 663 * 664 * @return pdTRUE an item was successfully received from the queue, otherwise 665 * pdFALSE. 666 * 667 * Example usage: 668 <pre> 669 // A co-routine that posts a character to a queue then blocks for a fixed 670 // period. The character is incremented each time. 671 static void vSendingCoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex ) 672 { 673 // cChar holds its value while this co-routine is blocked and must therefore 674 // be declared static. 675 static char cCharToTx = 'a'; 676 BaseType_t xResult; 677 678 // All co-routines must start with a call to crSTART(). 679 crSTART( xHandle ); 680 681 for( ;; ) 682 { 683 // Send the next character to the queue. 684 crQUEUE_SEND( xHandle, xCoRoutineQueue, &cCharToTx, NO_DELAY, &xResult ); 685 686 if( xResult == pdPASS ) 687 { 688 // The character was successfully posted to the queue. 689 } 690 else 691 { 692 // Could not post the character to the queue. 693 } 694 695 // Enable the UART Tx interrupt to cause an interrupt in this 696 // hypothetical UART. The interrupt will obtain the character 697 // from the queue and send it. 698 ENABLE_RX_INTERRUPT(); 699 700 // Increment to the next character then block for a fixed period. 701 // cCharToTx will maintain its value across the delay as it is 702 // declared static. 703 cCharToTx++; 704 if( cCharToTx > 'x' ) 705 { 706 cCharToTx = 'a'; 707 } 708 crDELAY( 100 ); 709 } 710 711 // All co-routines must end with a call to crEND(). 712 crEND(); 713 } 714 715 // An ISR that uses a queue to receive characters to send on a UART. 716 void vUART_ISR( void ) 717 { 718 char cCharToTx; 719 BaseType_t xCRWokenByPost = pdFALSE; 720 721 while( UART_TX_REG_EMPTY() ) 722 { 723 // Are there any characters in the queue waiting to be sent? 724 // xCRWokenByPost will automatically be set to pdTRUE if a co-routine 725 // is woken by the post - ensuring that only a single co-routine is 726 // woken no matter how many times we go around this loop. 727 if( crQUEUE_RECEIVE_FROM_ISR( pxQueue, &cCharToTx, &xCRWokenByPost ) ) 728 { 729 SEND_CHARACTER( cCharToTx ); 730 } 731 } 732 }</pre> 733 * \defgroup crQUEUE_RECEIVE_FROM_ISR crQUEUE_RECEIVE_FROM_ISR 734 * \ingroup Tasks 735 */ 736 #define crQUEUE_RECEIVE_FROM_ISR( pxQueue, pvBuffer, pxCoRoutineWoken ) xQueueCRReceiveFromISR( ( pxQueue ), ( pvBuffer ), ( pxCoRoutineWoken ) ) 737 738 /* 739 * This function is intended for internal use by the co-routine macros only. 740 * The macro nature of the co-routine implementation requires that the 741 * prototype appears here. The function should not be used by application 742 * writers. 743 * 744 * Removes the current co-routine from its ready list and places it in the 745 * appropriate delayed list. 746 */ 747 void vCoRoutineAddToDelayedList( TickType_t xTicksToDelay, List_t *pxEventList ); 748 749 /* 750 * This function is intended for internal use by the queue implementation only. 751 * The function should not be used by application writers. 752 * 753 * Removes the highest priority co-routine from the event list and places it in 754 * the pending ready list. 755 */ 756 BaseType_t xCoRoutineRemoveFromEventList( const List_t *pxEventList ); 757 758 #ifdef __cplusplus 759 } 760 #endif 761 762 #endif /* CO_ROUTINE_H */ 763