Port of TI's CC3100 Websock camera demo. Using FreeRTOS, mbedTLS, also parts of Arducam for cams ov5642 and 0v2640. Can also use MT9D111. Work in progress. Be warned some parts maybe a bit flacky. This is for Seeed Arch max only, for an M3, see the demo for CM3 using the 0v5642 aducam mini.
timers.h
00001 /* 00002 FreeRTOS V8.2.1 - Copyright (C) 2015 Real Time Engineers Ltd. 00003 All rights reserved 00004 00005 VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. 00006 00007 This file is part of the FreeRTOS distribution. 00008 00009 FreeRTOS is free software; you can redistribute it and/or modify it under 00010 the terms of the GNU General Public License (version 2) as published by the 00011 Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception. 00012 00013 *************************************************************************** 00014 >>! 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Low cost OpenRTOS 00061 licenses offer ticketed support, indemnification and commercial middleware. 00062 00063 http://www.SafeRTOS.com - High Integrity Systems also provide a safety 00064 engineered and independently SIL3 certified version for use in safety and 00065 mission critical applications that require provable dependability. 00066 00067 1 tab == 4 spaces! 00068 */ 00069 00070 00071 #ifndef TIMERS_H 00072 #define TIMERS_H 00073 00074 #ifndef INC_FREERTOS_H 00075 #error "include FreeRTOS.h must appear in source files before include timers.h" 00076 #endif 00077 00078 /*lint -e537 This headers are only multiply included if the application code 00079 happens to also be including task.h. */ 00080 #include "task.h" 00081 /*lint +e537 */ 00082 00083 #ifdef __cplusplus 00084 extern "C" { 00085 #endif 00086 00087 /*----------------------------------------------------------- 00088 * MACROS AND DEFINITIONS 00089 *----------------------------------------------------------*/ 00090 00091 /* IDs for commands that can be sent/received on the timer queue. These are to 00092 be used solely through the macros that make up the public software timer API, 00093 as defined below. The commands that are sent from interrupts must use the 00094 highest numbers as tmrFIRST_FROM_ISR_COMMAND is used to determine if the task 00095 or interrupt version of the queue send function should be used. */ 00096 #define tmrCOMMAND_EXECUTE_CALLBACK_FROM_ISR ( ( BaseType_t ) -2 ) 00097 #define tmrCOMMAND_EXECUTE_CALLBACK ( ( BaseType_t ) -1 ) 00098 #define tmrCOMMAND_START_DONT_TRACE ( ( BaseType_t ) 0 ) 00099 #define tmrCOMMAND_START ( ( BaseType_t ) 1 ) 00100 #define tmrCOMMAND_RESET ( ( BaseType_t ) 2 ) 00101 #define tmrCOMMAND_STOP ( ( BaseType_t ) 3 ) 00102 #define tmrCOMMAND_CHANGE_PERIOD ( ( BaseType_t ) 4 ) 00103 #define tmrCOMMAND_DELETE ( ( BaseType_t ) 5 ) 00104 00105 #define tmrFIRST_FROM_ISR_COMMAND ( ( BaseType_t ) 6 ) 00106 #define tmrCOMMAND_START_FROM_ISR ( ( BaseType_t ) 6 ) 00107 #define tmrCOMMAND_RESET_FROM_ISR ( ( BaseType_t ) 7 ) 00108 #define tmrCOMMAND_STOP_FROM_ISR ( ( BaseType_t ) 8 ) 00109 #define tmrCOMMAND_CHANGE_PERIOD_FROM_ISR ( ( BaseType_t ) 9 ) 00110 00111 00112 /** 00113 * Type by which software timers are referenced. For example, a call to 00114 * xTimerCreate() returns an TimerHandle_t variable that can then be used to 00115 * reference the subject timer in calls to other software timer API functions 00116 * (for example, xTimerStart(), xTimerReset(), etc.). 00117 */ 00118 typedef void * TimerHandle_t; 00119 00120 /* 00121 * Defines the prototype to which timer callback functions must conform. 00122 */ 00123 typedef void (*TimerCallbackFunction_t)( TimerHandle_t xTimer ); 00124 00125 /* 00126 * Defines the prototype to which functions used with the 00127 * xTimerPendFunctionCallFromISR() function must conform. 00128 */ 00129 typedef void (*PendedFunction_t)( void *, uint32_t ); 00130 00131 /** 00132 * TimerHandle_t xTimerCreate( const char * const pcTimerName, 00133 * TickType_t xTimerPeriodInTicks, 00134 * UBaseType_t uxAutoReload, 00135 * void * pvTimerID, 00136 * TimerCallbackFunction_t pxCallbackFunction ); 00137 * 00138 * Creates a new software timer instance. This allocates the storage required 00139 * by the new timer, initialises the new timers internal state, and returns a 00140 * handle by which the new timer can be referenced. 00141 * 00142 * Timers are created in the dormant state. The xTimerStart(), xTimerReset(), 00143 * xTimerStartFromISR(), xTimerResetFromISR(), xTimerChangePeriod() and 00144 * xTimerChangePeriodFromISR() API functions can all be used to transition a 00145 * timer into the active state. 00146 * 00147 * @param pcTimerName A text name that is assigned to the timer. This is done 00148 * purely to assist debugging. The kernel itself only ever references a timer 00149 * by its handle, and never by its name. 00150 * 00151 * @param xTimerPeriodInTicks The timer period. The time is defined in tick 00152 * periods so the constant portTICK_PERIOD_MS can be used to convert a time that 00153 * has been specified in milliseconds. For example, if the timer must expire 00154 * after 100 ticks, then xTimerPeriodInTicks should be set to 100. 00155 * Alternatively, if the timer must expire after 500ms, then xPeriod can be set 00156 * to ( 500 / portTICK_PERIOD_MS ) provided configTICK_RATE_HZ is less than or 00157 * equal to 1000. 00158 * 00159 * @param uxAutoReload If uxAutoReload is set to pdTRUE then the timer will 00160 * expire repeatedly with a frequency set by the xTimerPeriodInTicks parameter. 00161 * If uxAutoReload is set to pdFALSE then the timer will be a one-shot timer and 00162 * enter the dormant state after it expires. 00163 * 00164 * @param pvTimerID An identifier that is assigned to the timer being created. 00165 * Typically this would be used in the timer callback function to identify which 00166 * timer expired when the same callback function is assigned to more than one 00167 * timer. 00168 * 00169 * @param pxCallbackFunction The function to call when the timer expires. 00170 * Callback functions must have the prototype defined by TimerCallbackFunction_t, 00171 * which is "void vCallbackFunction( TimerHandle_t xTimer );". 00172 * 00173 * @return If the timer is successfully created then a handle to the newly 00174 * created timer is returned. If the timer cannot be created (because either 00175 * there is insufficient FreeRTOS heap remaining to allocate the timer 00176 * structures, or the timer period was set to 0) then NULL is returned. 00177 * 00178 * Example usage: 00179 * @verbatim 00180 * #define NUM_TIMERS 5 00181 * 00182 * // An array to hold handles to the created timers. 00183 * TimerHandle_t xTimers[ NUM_TIMERS ]; 00184 * 00185 * // An array to hold a count of the number of times each timer expires. 00186 * int32_t lExpireCounters[ NUM_TIMERS ] = { 0 }; 00187 * 00188 * // Define a callback function that will be used by multiple timer instances. 00189 * // The callback function does nothing but count the number of times the 00190 * // associated timer expires, and stop the timer once the timer has expired 00191 * // 10 times. 00192 * void vTimerCallback( TimerHandle_t pxTimer ) 00193 * { 00194 * int32_t lArrayIndex; 00195 * const int32_t xMaxExpiryCountBeforeStopping = 10; 00196 * 00197 * // Optionally do something if the pxTimer parameter is NULL. 00198 * configASSERT( pxTimer ); 00199 * 00200 * // Which timer expired? 00201 * lArrayIndex = ( int32_t ) pvTimerGetTimerID( pxTimer ); 00202 * 00203 * // Increment the number of times that pxTimer has expired. 00204 * lExpireCounters[ lArrayIndex ] += 1; 00205 * 00206 * // If the timer has expired 10 times then stop it from running. 00207 * if( lExpireCounters[ lArrayIndex ] == xMaxExpiryCountBeforeStopping ) 00208 * { 00209 * // Do not use a block time if calling a timer API function from a 00210 * // timer callback function, as doing so could cause a deadlock! 00211 * xTimerStop( pxTimer, 0 ); 00212 * } 00213 * } 00214 * 00215 * void main( void ) 00216 * { 00217 * int32_t x; 00218 * 00219 * // Create then start some timers. Starting the timers before the scheduler 00220 * // has been started means the timers will start running immediately that 00221 * // the scheduler starts. 00222 * for( x = 0; x < NUM_TIMERS; x++ ) 00223 * { 00224 * xTimers[ x ] = xTimerCreate( "Timer", // Just a text name, not used by the kernel. 00225 * ( 100 * x ), // The timer period in ticks. 00226 * pdTRUE, // The timers will auto-reload themselves when they expire. 00227 * ( void * ) x, // Assign each timer a unique id equal to its array index. 00228 * vTimerCallback // Each timer calls the same callback when it expires. 00229 * ); 00230 * 00231 * if( xTimers[ x ] == NULL ) 00232 * { 00233 * // The timer was not created. 00234 * } 00235 * else 00236 * { 00237 * // Start the timer. No block time is specified, and even if one was 00238 * // it would be ignored because the scheduler has not yet been 00239 * // started. 00240 * if( xTimerStart( xTimers[ x ], 0 ) != pdPASS ) 00241 * { 00242 * // The timer could not be set into the Active state. 00243 * } 00244 * } 00245 * } 00246 * 00247 * // ... 00248 * // Create tasks here. 00249 * // ... 00250 * 00251 * // Starting the scheduler will start the timers running as they have already 00252 * // been set into the active state. 00253 * xTaskStartScheduler(); 00254 * 00255 * // Should not reach here. 00256 * for( ;; ); 00257 * } 00258 * @endverbatim 00259 */ 00260 TimerHandle_t xTimerCreate( const char * const pcTimerName, const TickType_t xTimerPeriodInTicks, const UBaseType_t uxAutoReload, void * const pvTimerID, TimerCallbackFunction_t pxCallbackFunction ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */ 00261 00262 /** 00263 * void *pvTimerGetTimerID( TimerHandle_t xTimer ); 00264 * 00265 * Returns the ID assigned to the timer. 00266 * 00267 * IDs are assigned to timers using the pvTimerID parameter of the call to 00268 * xTimerCreated() that was used to create the timer, and by calling the 00269 * vTimerSetTimerID() API function. 00270 * 00271 * If the same callback function is assigned to multiple timers then the timer 00272 * ID can be used as time specific (timer local) storage. 00273 * 00274 * @param xTimer The timer being queried. 00275 * 00276 * @return The ID assigned to the timer being queried. 00277 * 00278 * Example usage: 00279 * 00280 * See the xTimerCreate() API function example usage scenario. 00281 */ 00282 void *pvTimerGetTimerID( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; 00283 00284 /** 00285 * void vTimerSetTimerID( TimerHandle_t xTimer, void *pvNewID ); 00286 * 00287 * Sets the ID assigned to the timer. 00288 * 00289 * IDs are assigned to timers using the pvTimerID parameter of the call to 00290 * xTimerCreated() that was used to create the timer. 00291 * 00292 * If the same callback function is assigned to multiple timers then the timer 00293 * ID can be used as time specific (timer local) storage. 00294 * 00295 * @param xTimer The timer being updated. 00296 * 00297 * @param pvNewID The ID to assign to the timer. 00298 * 00299 * Example usage: 00300 * 00301 * See the xTimerCreate() API function example usage scenario. 00302 */ 00303 void vTimerSetTimerID( const TimerHandle_t xTimer, void *pvNewID ) PRIVILEGED_FUNCTION; 00304 00305 /** 00306 * BaseType_t xTimerIsTimerActive( TimerHandle_t xTimer ); 00307 * 00308 * Queries a timer to see if it is active or dormant. 00309 * 00310 * A timer will be dormant if: 00311 * 1) It has been created but not started, or 00312 * 2) It is an expired one-shot timer that has not been restarted. 00313 * 00314 * Timers are created in the dormant state. The xTimerStart(), xTimerReset(), 00315 * xTimerStartFromISR(), xTimerResetFromISR(), xTimerChangePeriod() and 00316 * xTimerChangePeriodFromISR() API functions can all be used to transition a timer into the 00317 * active state. 00318 * 00319 * @param xTimer The timer being queried. 00320 * 00321 * @return pdFALSE will be returned if the timer is dormant. A value other than 00322 * pdFALSE will be returned if the timer is active. 00323 * 00324 * Example usage: 00325 * @verbatim 00326 * // This function assumes xTimer has already been created. 00327 * void vAFunction( TimerHandle_t xTimer ) 00328 * { 00329 * if( xTimerIsTimerActive( xTimer ) != pdFALSE ) // or more simply and equivalently "if( xTimerIsTimerActive( xTimer ) )" 00330 * { 00331 * // xTimer is active, do something. 00332 * } 00333 * else 00334 * { 00335 * // xTimer is not active, do something else. 00336 * } 00337 * } 00338 * @endverbatim 00339 */ 00340 BaseType_t xTimerIsTimerActive( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; 00341 00342 /** 00343 * TaskHandle_t xTimerGetTimerDaemonTaskHandle( void ); 00344 * 00345 * xTimerGetTimerDaemonTaskHandle() is only available if 00346 * INCLUDE_xTimerGetTimerDaemonTaskHandle is set to 1 in FreeRTOSConfig.h. 00347 * 00348 * Simply returns the handle of the timer service/daemon task. It it not valid 00349 * to call xTimerGetTimerDaemonTaskHandle() before the scheduler has been started. 00350 */ 00351 TaskHandle_t xTimerGetTimerDaemonTaskHandle( void ); 00352 00353 /** 00354 * BaseType_t xTimerStart( TimerHandle_t xTimer, TickType_t xTicksToWait ); 00355 * 00356 * Timer functionality is provided by a timer service/daemon task. Many of the 00357 * public FreeRTOS timer API functions send commands to the timer service task 00358 * through a queue called the timer command queue. The timer command queue is 00359 * private to the kernel itself and is not directly accessible to application 00360 * code. The length of the timer command queue is set by the 00361 * configTIMER_QUEUE_LENGTH configuration constant. 00362 * 00363 * xTimerStart() starts a timer that was previously created using the 00364 * xTimerCreate() API function. If the timer had already been started and was 00365 * already in the active state, then xTimerStart() has equivalent functionality 00366 * to the xTimerReset() API function. 00367 * 00368 * Starting a timer ensures the timer is in the active state. If the timer 00369 * is not stopped, deleted, or reset in the mean time, the callback function 00370 * associated with the timer will get called 'n' ticks after xTimerStart() was 00371 * called, where 'n' is the timers defined period. 00372 * 00373 * It is valid to call xTimerStart() before the scheduler has been started, but 00374 * when this is done the timer will not actually start until the scheduler is 00375 * started, and the timers expiry time will be relative to when the scheduler is 00376 * started, not relative to when xTimerStart() was called. 00377 * 00378 * The configUSE_TIMERS configuration constant must be set to 1 for xTimerStart() 00379 * to be available. 00380 * 00381 * @param xTimer The handle of the timer being started/restarted. 00382 * 00383 * @param xTicksToWait Specifies the time, in ticks, that the calling task should 00384 * be held in the Blocked state to wait for the start command to be successfully 00385 * sent to the timer command queue, should the queue already be full when 00386 * xTimerStart() was called. xTicksToWait is ignored if xTimerStart() is called 00387 * before the scheduler is started. 00388 * 00389 * @return pdFAIL will be returned if the start command could not be sent to 00390 * the timer command queue even after xTicksToWait ticks had passed. pdPASS will 00391 * be returned if the command was successfully sent to the timer command queue. 00392 * When the command is actually processed will depend on the priority of the 00393 * timer service/daemon task relative to other tasks in the system, although the 00394 * timers expiry time is relative to when xTimerStart() is actually called. The 00395 * timer service/daemon task priority is set by the configTIMER_TASK_PRIORITY 00396 * configuration constant. 00397 * 00398 * Example usage: 00399 * 00400 * See the xTimerCreate() API function example usage scenario. 00401 * 00402 */ 00403 #define xTimerStart( xTimer, xTicksToWait ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_START, ( xTaskGetTickCount() ), NULL, ( xTicksToWait ) ) 00404 00405 /** 00406 * BaseType_t xTimerStop( TimerHandle_t xTimer, TickType_t xTicksToWait ); 00407 * 00408 * Timer functionality is provided by a timer service/daemon task. Many of the 00409 * public FreeRTOS timer API functions send commands to the timer service task 00410 * through a queue called the timer command queue. The timer command queue is 00411 * private to the kernel itself and is not directly accessible to application 00412 * code. The length of the timer command queue is set by the 00413 * configTIMER_QUEUE_LENGTH configuration constant. 00414 * 00415 * xTimerStop() stops a timer that was previously started using either of the 00416 * The xTimerStart(), xTimerReset(), xTimerStartFromISR(), xTimerResetFromISR(), 00417 * xTimerChangePeriod() or xTimerChangePeriodFromISR() API functions. 00418 * 00419 * Stopping a timer ensures the timer is not in the active state. 00420 * 00421 * The configUSE_TIMERS configuration constant must be set to 1 for xTimerStop() 00422 * to be available. 00423 * 00424 * @param xTimer The handle of the timer being stopped. 00425 * 00426 * @param xTicksToWait Specifies the time, in ticks, that the calling task should 00427 * be held in the Blocked state to wait for the stop command to be successfully 00428 * sent to the timer command queue, should the queue already be full when 00429 * xTimerStop() was called. xTicksToWait is ignored if xTimerStop() is called 00430 * before the scheduler is started. 00431 * 00432 * @return pdFAIL will be returned if the stop command could not be sent to 00433 * the timer command queue even after xTicksToWait ticks had passed. pdPASS will 00434 * be returned if the command was successfully sent to the timer command queue. 00435 * When the command is actually processed will depend on the priority of the 00436 * timer service/daemon task relative to other tasks in the system. The timer 00437 * service/daemon task priority is set by the configTIMER_TASK_PRIORITY 00438 * configuration constant. 00439 * 00440 * Example usage: 00441 * 00442 * See the xTimerCreate() API function example usage scenario. 00443 * 00444 */ 00445 #define xTimerStop( xTimer, xTicksToWait ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_STOP, 0U, NULL, ( xTicksToWait ) ) 00446 00447 /** 00448 * BaseType_t xTimerChangePeriod( TimerHandle_t xTimer, 00449 * TickType_t xNewPeriod, 00450 * TickType_t xTicksToWait ); 00451 * 00452 * Timer functionality is provided by a timer service/daemon task. Many of the 00453 * public FreeRTOS timer API functions send commands to the timer service task 00454 * through a queue called the timer command queue. The timer command queue is 00455 * private to the kernel itself and is not directly accessible to application 00456 * code. The length of the timer command queue is set by the 00457 * configTIMER_QUEUE_LENGTH configuration constant. 00458 * 00459 * xTimerChangePeriod() changes the period of a timer that was previously 00460 * created using the xTimerCreate() API function. 00461 * 00462 * xTimerChangePeriod() can be called to change the period of an active or 00463 * dormant state timer. 00464 * 00465 * The configUSE_TIMERS configuration constant must be set to 1 for 00466 * xTimerChangePeriod() to be available. 00467 * 00468 * @param xTimer The handle of the timer that is having its period changed. 00469 * 00470 * @param xNewPeriod The new period for xTimer. Timer periods are specified in 00471 * tick periods, so the constant portTICK_PERIOD_MS can be used to convert a time 00472 * that has been specified in milliseconds. For example, if the timer must 00473 * expire after 100 ticks, then xNewPeriod should be set to 100. Alternatively, 00474 * if the timer must expire after 500ms, then xNewPeriod can be set to 00475 * ( 500 / portTICK_PERIOD_MS ) provided configTICK_RATE_HZ is less than 00476 * or equal to 1000. 00477 * 00478 * @param xTicksToWait Specifies the time, in ticks, that the calling task should 00479 * be held in the Blocked state to wait for the change period command to be 00480 * successfully sent to the timer command queue, should the queue already be 00481 * full when xTimerChangePeriod() was called. xTicksToWait is ignored if 00482 * xTimerChangePeriod() is called before the scheduler is started. 00483 * 00484 * @return pdFAIL will be returned if the change period command could not be 00485 * sent to the timer command queue even after xTicksToWait ticks had passed. 00486 * pdPASS will be returned if the command was successfully sent to the timer 00487 * command queue. When the command is actually processed will depend on the 00488 * priority of the timer service/daemon task relative to other tasks in the 00489 * system. The timer service/daemon task priority is set by the 00490 * configTIMER_TASK_PRIORITY configuration constant. 00491 * 00492 * Example usage: 00493 * @verbatim 00494 * // This function assumes xTimer has already been created. If the timer 00495 * // referenced by xTimer is already active when it is called, then the timer 00496 * // is deleted. If the timer referenced by xTimer is not active when it is 00497 * // called, then the period of the timer is set to 500ms and the timer is 00498 * // started. 00499 * void vAFunction( TimerHandle_t xTimer ) 00500 * { 00501 * if( xTimerIsTimerActive( xTimer ) != pdFALSE ) // or more simply and equivalently "if( xTimerIsTimerActive( xTimer ) )" 00502 * { 00503 * // xTimer is already active - delete it. 00504 * xTimerDelete( xTimer ); 00505 * } 00506 * else 00507 * { 00508 * // xTimer is not active, change its period to 500ms. This will also 00509 * // cause the timer to start. Block for a maximum of 100 ticks if the 00510 * // change period command cannot immediately be sent to the timer 00511 * // command queue. 00512 * if( xTimerChangePeriod( xTimer, 500 / portTICK_PERIOD_MS, 100 ) == pdPASS ) 00513 * { 00514 * // The command was successfully sent. 00515 * } 00516 * else 00517 * { 00518 * // The command could not be sent, even after waiting for 100 ticks 00519 * // to pass. Take appropriate action here. 00520 * } 00521 * } 00522 * } 00523 * @endverbatim 00524 */ 00525 #define xTimerChangePeriod( xTimer, xNewPeriod, xTicksToWait ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_CHANGE_PERIOD, ( xNewPeriod ), NULL, ( xTicksToWait ) ) 00526 00527 /** 00528 * BaseType_t xTimerDelete( TimerHandle_t xTimer, TickType_t xTicksToWait ); 00529 * 00530 * Timer functionality is provided by a timer service/daemon task. Many of the 00531 * public FreeRTOS timer API functions send commands to the timer service task 00532 * through a queue called the timer command queue. The timer command queue is 00533 * private to the kernel itself and is not directly accessible to application 00534 * code. The length of the timer command queue is set by the 00535 * configTIMER_QUEUE_LENGTH configuration constant. 00536 * 00537 * xTimerDelete() deletes a timer that was previously created using the 00538 * xTimerCreate() API function. 00539 * 00540 * The configUSE_TIMERS configuration constant must be set to 1 for 00541 * xTimerDelete() to be available. 00542 * 00543 * @param xTimer The handle of the timer being deleted. 00544 * 00545 * @param xTicksToWait Specifies the time, in ticks, that the calling task should 00546 * be held in the Blocked state to wait for the delete command to be 00547 * successfully sent to the timer command queue, should the queue already be 00548 * full when xTimerDelete() was called. xTicksToWait is ignored if xTimerDelete() 00549 * is called before the scheduler is started. 00550 * 00551 * @return pdFAIL will be returned if the delete command could not be sent to 00552 * the timer command queue even after xTicksToWait ticks had passed. pdPASS will 00553 * be returned if the command was successfully sent to the timer command queue. 00554 * When the command is actually processed will depend on the priority of the 00555 * timer service/daemon task relative to other tasks in the system. The timer 00556 * service/daemon task priority is set by the configTIMER_TASK_PRIORITY 00557 * configuration constant. 00558 * 00559 * Example usage: 00560 * 00561 * See the xTimerChangePeriod() API function example usage scenario. 00562 */ 00563 #define xTimerDelete( xTimer, xTicksToWait ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_DELETE, 0U, NULL, ( xTicksToWait ) ) 00564 00565 /** 00566 * BaseType_t xTimerReset( TimerHandle_t xTimer, TickType_t xTicksToWait ); 00567 * 00568 * Timer functionality is provided by a timer service/daemon task. Many of the 00569 * public FreeRTOS timer API functions send commands to the timer service task 00570 * through a queue called the timer command queue. The timer command queue is 00571 * private to the kernel itself and is not directly accessible to application 00572 * code. The length of the timer command queue is set by the 00573 * configTIMER_QUEUE_LENGTH configuration constant. 00574 * 00575 * xTimerReset() re-starts a timer that was previously created using the 00576 * xTimerCreate() API function. If the timer had already been started and was 00577 * already in the active state, then xTimerReset() will cause the timer to 00578 * re-evaluate its expiry time so that it is relative to when xTimerReset() was 00579 * called. If the timer was in the dormant state then xTimerReset() has 00580 * equivalent functionality to the xTimerStart() API function. 00581 * 00582 * Resetting a timer ensures the timer is in the active state. If the timer 00583 * is not stopped, deleted, or reset in the mean time, the callback function 00584 * associated with the timer will get called 'n' ticks after xTimerReset() was 00585 * called, where 'n' is the timers defined period. 00586 * 00587 * It is valid to call xTimerReset() before the scheduler has been started, but 00588 * when this is done the timer will not actually start until the scheduler is 00589 * started, and the timers expiry time will be relative to when the scheduler is 00590 * started, not relative to when xTimerReset() was called. 00591 * 00592 * The configUSE_TIMERS configuration constant must be set to 1 for xTimerReset() 00593 * to be available. 00594 * 00595 * @param xTimer The handle of the timer being reset/started/restarted. 00596 * 00597 * @param xTicksToWait Specifies the time, in ticks, that the calling task should 00598 * be held in the Blocked state to wait for the reset command to be successfully 00599 * sent to the timer command queue, should the queue already be full when 00600 * xTimerReset() was called. xTicksToWait is ignored if xTimerReset() is called 00601 * before the scheduler is started. 00602 * 00603 * @return pdFAIL will be returned if the reset command could not be sent to 00604 * the timer command queue even after xTicksToWait ticks had passed. pdPASS will 00605 * be returned if the command was successfully sent to the timer command queue. 00606 * When the command is actually processed will depend on the priority of the 00607 * timer service/daemon task relative to other tasks in the system, although the 00608 * timers expiry time is relative to when xTimerStart() is actually called. The 00609 * timer service/daemon task priority is set by the configTIMER_TASK_PRIORITY 00610 * configuration constant. 00611 * 00612 * Example usage: 00613 * @verbatim 00614 * // When a key is pressed, an LCD back-light is switched on. If 5 seconds pass 00615 * // without a key being pressed, then the LCD back-light is switched off. In 00616 * // this case, the timer is a one-shot timer. 00617 * 00618 * TimerHandle_t xBacklightTimer = NULL; 00619 * 00620 * // The callback function assigned to the one-shot timer. In this case the 00621 * // parameter is not used. 00622 * void vBacklightTimerCallback( TimerHandle_t pxTimer ) 00623 * { 00624 * // The timer expired, therefore 5 seconds must have passed since a key 00625 * // was pressed. Switch off the LCD back-light. 00626 * vSetBacklightState( BACKLIGHT_OFF ); 00627 * } 00628 * 00629 * // The key press event handler. 00630 * void vKeyPressEventHandler( char cKey ) 00631 * { 00632 * // Ensure the LCD back-light is on, then reset the timer that is 00633 * // responsible for turning the back-light off after 5 seconds of 00634 * // key inactivity. Wait 10 ticks for the command to be successfully sent 00635 * // if it cannot be sent immediately. 00636 * vSetBacklightState( BACKLIGHT_ON ); 00637 * if( xTimerReset( xBacklightTimer, 100 ) != pdPASS ) 00638 * { 00639 * // The reset command was not executed successfully. Take appropriate 00640 * // action here. 00641 * } 00642 * 00643 * // Perform the rest of the key processing here. 00644 * } 00645 * 00646 * void main( void ) 00647 * { 00648 * int32_t x; 00649 * 00650 * // Create then start the one-shot timer that is responsible for turning 00651 * // the back-light off if no keys are pressed within a 5 second period. 00652 * xBacklightTimer = xTimerCreate( "BacklightTimer", // Just a text name, not used by the kernel. 00653 * ( 5000 / portTICK_PERIOD_MS), // The timer period in ticks. 00654 * pdFALSE, // The timer is a one-shot timer. 00655 * 0, // The id is not used by the callback so can take any value. 00656 * vBacklightTimerCallback // The callback function that switches the LCD back-light off. 00657 * ); 00658 * 00659 * if( xBacklightTimer == NULL ) 00660 * { 00661 * // The timer was not created. 00662 * } 00663 * else 00664 * { 00665 * // Start the timer. No block time is specified, and even if one was 00666 * // it would be ignored because the scheduler has not yet been 00667 * // started. 00668 * if( xTimerStart( xBacklightTimer, 0 ) != pdPASS ) 00669 * { 00670 * // The timer could not be set into the Active state. 00671 * } 00672 * } 00673 * 00674 * // ... 00675 * // Create tasks here. 00676 * // ... 00677 * 00678 * // Starting the scheduler will start the timer running as it has already 00679 * // been set into the active state. 00680 * xTaskStartScheduler(); 00681 * 00682 * // Should not reach here. 00683 * for( ;; ); 00684 * } 00685 * @endverbatim 00686 */ 00687 #define xTimerReset( xTimer, xTicksToWait ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_RESET, ( xTaskGetTickCount() ), NULL, ( xTicksToWait ) ) 00688 00689 /** 00690 * BaseType_t xTimerStartFromISR( TimerHandle_t xTimer, 00691 * BaseType_t *pxHigherPriorityTaskWoken ); 00692 * 00693 * A version of xTimerStart() that can be called from an interrupt service 00694 * routine. 00695 * 00696 * @param xTimer The handle of the timer being started/restarted. 00697 * 00698 * @param pxHigherPriorityTaskWoken The timer service/daemon task spends most 00699 * of its time in the Blocked state, waiting for messages to arrive on the timer 00700 * command queue. Calling xTimerStartFromISR() writes a message to the timer 00701 * command queue, so has the potential to transition the timer service/daemon 00702 * task out of the Blocked state. If calling xTimerStartFromISR() causes the 00703 * timer service/daemon task to leave the Blocked state, and the timer service/ 00704 * daemon task has a priority equal to or greater than the currently executing 00705 * task (the task that was interrupted), then *pxHigherPriorityTaskWoken will 00706 * get set to pdTRUE internally within the xTimerStartFromISR() function. If 00707 * xTimerStartFromISR() sets this value to pdTRUE then a context switch should 00708 * be performed before the interrupt exits. 00709 * 00710 * @return pdFAIL will be returned if the start command could not be sent to 00711 * the timer command queue. pdPASS will be returned if the command was 00712 * successfully sent to the timer command queue. When the command is actually 00713 * processed will depend on the priority of the timer service/daemon task 00714 * relative to other tasks in the system, although the timers expiry time is 00715 * relative to when xTimerStartFromISR() is actually called. The timer 00716 * service/daemon task priority is set by the configTIMER_TASK_PRIORITY 00717 * configuration constant. 00718 * 00719 * Example usage: 00720 * @verbatim 00721 * // This scenario assumes xBacklightTimer has already been created. When a 00722 * // key is pressed, an LCD back-light is switched on. If 5 seconds pass 00723 * // without a key being pressed, then the LCD back-light is switched off. In 00724 * // this case, the timer is a one-shot timer, and unlike the example given for 00725 * // the xTimerReset() function, the key press event handler is an interrupt 00726 * // service routine. 00727 * 00728 * // The callback function assigned to the one-shot timer. In this case the 00729 * // parameter is not used. 00730 * void vBacklightTimerCallback( TimerHandle_t pxTimer ) 00731 * { 00732 * // The timer expired, therefore 5 seconds must have passed since a key 00733 * // was pressed. Switch off the LCD back-light. 00734 * vSetBacklightState( BACKLIGHT_OFF ); 00735 * } 00736 * 00737 * // The key press interrupt service routine. 00738 * void vKeyPressEventInterruptHandler( void ) 00739 * { 00740 * BaseType_t xHigherPriorityTaskWoken = pdFALSE; 00741 * 00742 * // Ensure the LCD back-light is on, then restart the timer that is 00743 * // responsible for turning the back-light off after 5 seconds of 00744 * // key inactivity. This is an interrupt service routine so can only 00745 * // call FreeRTOS API functions that end in "FromISR". 00746 * vSetBacklightState( BACKLIGHT_ON ); 00747 * 00748 * // xTimerStartFromISR() or xTimerResetFromISR() could be called here 00749 * // as both cause the timer to re-calculate its expiry time. 00750 * // xHigherPriorityTaskWoken was initialised to pdFALSE when it was 00751 * // declared (in this function). 00752 * if( xTimerStartFromISR( xBacklightTimer, &xHigherPriorityTaskWoken ) != pdPASS ) 00753 * { 00754 * // The start command was not executed successfully. Take appropriate 00755 * // action here. 00756 * } 00757 * 00758 * // Perform the rest of the key processing here. 00759 * 00760 * // If xHigherPriorityTaskWoken equals pdTRUE, then a context switch 00761 * // should be performed. The syntax required to perform a context switch 00762 * // from inside an ISR varies from port to port, and from compiler to 00763 * // compiler. Inspect the demos for the port you are using to find the 00764 * // actual syntax required. 00765 * if( xHigherPriorityTaskWoken != pdFALSE ) 00766 * { 00767 * // Call the interrupt safe yield function here (actual function 00768 * // depends on the FreeRTOS port being used). 00769 * } 00770 * } 00771 * @endverbatim 00772 */ 00773 #define xTimerStartFromISR( xTimer, pxHigherPriorityTaskWoken ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_START_FROM_ISR, ( xTaskGetTickCountFromISR() ), ( pxHigherPriorityTaskWoken ), 0U ) 00774 00775 /** 00776 * BaseType_t xTimerStopFromISR( TimerHandle_t xTimer, 00777 * BaseType_t *pxHigherPriorityTaskWoken ); 00778 * 00779 * A version of xTimerStop() that can be called from an interrupt service 00780 * routine. 00781 * 00782 * @param xTimer The handle of the timer being stopped. 00783 * 00784 * @param pxHigherPriorityTaskWoken The timer service/daemon task spends most 00785 * of its time in the Blocked state, waiting for messages to arrive on the timer 00786 * command queue. Calling xTimerStopFromISR() writes a message to the timer 00787 * command queue, so has the potential to transition the timer service/daemon 00788 * task out of the Blocked state. If calling xTimerStopFromISR() causes the 00789 * timer service/daemon task to leave the Blocked state, and the timer service/ 00790 * daemon task has a priority equal to or greater than the currently executing 00791 * task (the task that was interrupted), then *pxHigherPriorityTaskWoken will 00792 * get set to pdTRUE internally within the xTimerStopFromISR() function. If 00793 * xTimerStopFromISR() sets this value to pdTRUE then a context switch should 00794 * be performed before the interrupt exits. 00795 * 00796 * @return pdFAIL will be returned if the stop command could not be sent to 00797 * the timer command queue. pdPASS will be returned if the command was 00798 * successfully sent to the timer command queue. When the command is actually 00799 * processed will depend on the priority of the timer service/daemon task 00800 * relative to other tasks in the system. The timer service/daemon task 00801 * priority is set by the configTIMER_TASK_PRIORITY configuration constant. 00802 * 00803 * Example usage: 00804 * @verbatim 00805 * // This scenario assumes xTimer has already been created and started. When 00806 * // an interrupt occurs, the timer should be simply stopped. 00807 * 00808 * // The interrupt service routine that stops the timer. 00809 * void vAnExampleInterruptServiceRoutine( void ) 00810 * { 00811 * BaseType_t xHigherPriorityTaskWoken = pdFALSE; 00812 * 00813 * // The interrupt has occurred - simply stop the timer. 00814 * // xHigherPriorityTaskWoken was set to pdFALSE where it was defined 00815 * // (within this function). As this is an interrupt service routine, only 00816 * // FreeRTOS API functions that end in "FromISR" can be used. 00817 * if( xTimerStopFromISR( xTimer, &xHigherPriorityTaskWoken ) != pdPASS ) 00818 * { 00819 * // The stop command was not executed successfully. Take appropriate 00820 * // action here. 00821 * } 00822 * 00823 * // If xHigherPriorityTaskWoken equals pdTRUE, then a context switch 00824 * // should be performed. The syntax required to perform a context switch 00825 * // from inside an ISR varies from port to port, and from compiler to 00826 * // compiler. Inspect the demos for the port you are using to find the 00827 * // actual syntax required. 00828 * if( xHigherPriorityTaskWoken != pdFALSE ) 00829 * { 00830 * // Call the interrupt safe yield function here (actual function 00831 * // depends on the FreeRTOS port being used). 00832 * } 00833 * } 00834 * @endverbatim 00835 */ 00836 #define xTimerStopFromISR( xTimer, pxHigherPriorityTaskWoken ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_STOP_FROM_ISR, 0, ( pxHigherPriorityTaskWoken ), 0U ) 00837 00838 /** 00839 * BaseType_t xTimerChangePeriodFromISR( TimerHandle_t xTimer, 00840 * TickType_t xNewPeriod, 00841 * BaseType_t *pxHigherPriorityTaskWoken ); 00842 * 00843 * A version of xTimerChangePeriod() that can be called from an interrupt 00844 * service routine. 00845 * 00846 * @param xTimer The handle of the timer that is having its period changed. 00847 * 00848 * @param xNewPeriod The new period for xTimer. Timer periods are specified in 00849 * tick periods, so the constant portTICK_PERIOD_MS can be used to convert a time 00850 * that has been specified in milliseconds. For example, if the timer must 00851 * expire after 100 ticks, then xNewPeriod should be set to 100. Alternatively, 00852 * if the timer must expire after 500ms, then xNewPeriod can be set to 00853 * ( 500 / portTICK_PERIOD_MS ) provided configTICK_RATE_HZ is less than 00854 * or equal to 1000. 00855 * 00856 * @param pxHigherPriorityTaskWoken The timer service/daemon task spends most 00857 * of its time in the Blocked state, waiting for messages to arrive on the timer 00858 * command queue. Calling xTimerChangePeriodFromISR() writes a message to the 00859 * timer command queue, so has the potential to transition the timer service/ 00860 * daemon task out of the Blocked state. If calling xTimerChangePeriodFromISR() 00861 * causes the timer service/daemon task to leave the Blocked state, and the 00862 * timer service/daemon task has a priority equal to or greater than the 00863 * currently executing task (the task that was interrupted), then 00864 * *pxHigherPriorityTaskWoken will get set to pdTRUE internally within the 00865 * xTimerChangePeriodFromISR() function. If xTimerChangePeriodFromISR() sets 00866 * this value to pdTRUE then a context switch should be performed before the 00867 * interrupt exits. 00868 * 00869 * @return pdFAIL will be returned if the command to change the timers period 00870 * could not be sent to the timer command queue. pdPASS will be returned if the 00871 * command was successfully sent to the timer command queue. When the command 00872 * is actually processed will depend on the priority of the timer service/daemon 00873 * task relative to other tasks in the system. The timer service/daemon task 00874 * priority is set by the configTIMER_TASK_PRIORITY configuration constant. 00875 * 00876 * Example usage: 00877 * @verbatim 00878 * // This scenario assumes xTimer has already been created and started. When 00879 * // an interrupt occurs, the period of xTimer should be changed to 500ms. 00880 * 00881 * // The interrupt service routine that changes the period of xTimer. 00882 * void vAnExampleInterruptServiceRoutine( void ) 00883 * { 00884 * BaseType_t xHigherPriorityTaskWoken = pdFALSE; 00885 * 00886 * // The interrupt has occurred - change the period of xTimer to 500ms. 00887 * // xHigherPriorityTaskWoken was set to pdFALSE where it was defined 00888 * // (within this function). As this is an interrupt service routine, only 00889 * // FreeRTOS API functions that end in "FromISR" can be used. 00890 * if( xTimerChangePeriodFromISR( xTimer, &xHigherPriorityTaskWoken ) != pdPASS ) 00891 * { 00892 * // The command to change the timers period was not executed 00893 * // successfully. Take appropriate action here. 00894 * } 00895 * 00896 * // If xHigherPriorityTaskWoken equals pdTRUE, then a context switch 00897 * // should be performed. The syntax required to perform a context switch 00898 * // from inside an ISR varies from port to port, and from compiler to 00899 * // compiler. Inspect the demos for the port you are using to find the 00900 * // actual syntax required. 00901 * if( xHigherPriorityTaskWoken != pdFALSE ) 00902 * { 00903 * // Call the interrupt safe yield function here (actual function 00904 * // depends on the FreeRTOS port being used). 00905 * } 00906 * } 00907 * @endverbatim 00908 */ 00909 #define xTimerChangePeriodFromISR( xTimer, xNewPeriod, pxHigherPriorityTaskWoken ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_CHANGE_PERIOD_FROM_ISR, ( xNewPeriod ), ( pxHigherPriorityTaskWoken ), 0U ) 00910 00911 /** 00912 * BaseType_t xTimerResetFromISR( TimerHandle_t xTimer, 00913 * BaseType_t *pxHigherPriorityTaskWoken ); 00914 * 00915 * A version of xTimerReset() that can be called from an interrupt service 00916 * routine. 00917 * 00918 * @param xTimer The handle of the timer that is to be started, reset, or 00919 * restarted. 00920 * 00921 * @param pxHigherPriorityTaskWoken The timer service/daemon task spends most 00922 * of its time in the Blocked state, waiting for messages to arrive on the timer 00923 * command queue. Calling xTimerResetFromISR() writes a message to the timer 00924 * command queue, so has the potential to transition the timer service/daemon 00925 * task out of the Blocked state. If calling xTimerResetFromISR() causes the 00926 * timer service/daemon task to leave the Blocked state, and the timer service/ 00927 * daemon task has a priority equal to or greater than the currently executing 00928 * task (the task that was interrupted), then *pxHigherPriorityTaskWoken will 00929 * get set to pdTRUE internally within the xTimerResetFromISR() function. If 00930 * xTimerResetFromISR() sets this value to pdTRUE then a context switch should 00931 * be performed before the interrupt exits. 00932 * 00933 * @return pdFAIL will be returned if the reset command could not be sent to 00934 * the timer command queue. pdPASS will be returned if the command was 00935 * successfully sent to the timer command queue. When the command is actually 00936 * processed will depend on the priority of the timer service/daemon task 00937 * relative to other tasks in the system, although the timers expiry time is 00938 * relative to when xTimerResetFromISR() is actually called. The timer service/daemon 00939 * task priority is set by the configTIMER_TASK_PRIORITY configuration constant. 00940 * 00941 * Example usage: 00942 * @verbatim 00943 * // This scenario assumes xBacklightTimer has already been created. When a 00944 * // key is pressed, an LCD back-light is switched on. If 5 seconds pass 00945 * // without a key being pressed, then the LCD back-light is switched off. In 00946 * // this case, the timer is a one-shot timer, and unlike the example given for 00947 * // the xTimerReset() function, the key press event handler is an interrupt 00948 * // service routine. 00949 * 00950 * // The callback function assigned to the one-shot timer. In this case the 00951 * // parameter is not used. 00952 * void vBacklightTimerCallback( TimerHandle_t pxTimer ) 00953 * { 00954 * // The timer expired, therefore 5 seconds must have passed since a key 00955 * // was pressed. Switch off the LCD back-light. 00956 * vSetBacklightState( BACKLIGHT_OFF ); 00957 * } 00958 * 00959 * // The key press interrupt service routine. 00960 * void vKeyPressEventInterruptHandler( void ) 00961 * { 00962 * BaseType_t xHigherPriorityTaskWoken = pdFALSE; 00963 * 00964 * // Ensure the LCD back-light is on, then reset the timer that is 00965 * // responsible for turning the back-light off after 5 seconds of 00966 * // key inactivity. This is an interrupt service routine so can only 00967 * // call FreeRTOS API functions that end in "FromISR". 00968 * vSetBacklightState( BACKLIGHT_ON ); 00969 * 00970 * // xTimerStartFromISR() or xTimerResetFromISR() could be called here 00971 * // as both cause the timer to re-calculate its expiry time. 00972 * // xHigherPriorityTaskWoken was initialised to pdFALSE when it was 00973 * // declared (in this function). 00974 * if( xTimerResetFromISR( xBacklightTimer, &xHigherPriorityTaskWoken ) != pdPASS ) 00975 * { 00976 * // The reset command was not executed successfully. Take appropriate 00977 * // action here. 00978 * } 00979 * 00980 * // Perform the rest of the key processing here. 00981 * 00982 * // If xHigherPriorityTaskWoken equals pdTRUE, then a context switch 00983 * // should be performed. The syntax required to perform a context switch 00984 * // from inside an ISR varies from port to port, and from compiler to 00985 * // compiler. Inspect the demos for the port you are using to find the 00986 * // actual syntax required. 00987 * if( xHigherPriorityTaskWoken != pdFALSE ) 00988 * { 00989 * // Call the interrupt safe yield function here (actual function 00990 * // depends on the FreeRTOS port being used). 00991 * } 00992 * } 00993 * @endverbatim 00994 */ 00995 #define xTimerResetFromISR( xTimer, pxHigherPriorityTaskWoken ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_RESET_FROM_ISR, ( xTaskGetTickCountFromISR() ), ( pxHigherPriorityTaskWoken ), 0U ) 00996 00997 00998 /** 00999 * BaseType_t xTimerPendFunctionCallFromISR( PendedFunction_t xFunctionToPend, 01000 * void *pvParameter1, 01001 * uint32_t ulParameter2, 01002 * BaseType_t *pxHigherPriorityTaskWoken ); 01003 * 01004 * 01005 * Used from application interrupt service routines to defer the execution of a 01006 * function to the RTOS daemon task (the timer service task, hence this function 01007 * is implemented in timers.c and is prefixed with 'Timer'). 01008 * 01009 * Ideally an interrupt service routine (ISR) is kept as short as possible, but 01010 * sometimes an ISR either has a lot of processing to do, or needs to perform 01011 * processing that is not deterministic. In these cases 01012 * xTimerPendFunctionCallFromISR() can be used to defer processing of a function 01013 * to the RTOS daemon task. 01014 * 01015 * A mechanism is provided that allows the interrupt to return directly to the 01016 * task that will subsequently execute the pended callback function. This 01017 * allows the callback function to execute contiguously in time with the 01018 * interrupt - just as if the callback had executed in the interrupt itself. 01019 * 01020 * @param xFunctionToPend The function to execute from the timer service/ 01021 * daemon task. The function must conform to the PendedFunction_t 01022 * prototype. 01023 * 01024 * @param pvParameter1 The value of the callback function's first parameter. 01025 * The parameter has a void * type to allow it to be used to pass any type. 01026 * For example, unsigned longs can be cast to a void *, or the void * can be 01027 * used to point to a structure. 01028 * 01029 * @param ulParameter2 The value of the callback function's second parameter. 01030 * 01031 * @param pxHigherPriorityTaskWoken As mentioned above, calling this function 01032 * will result in a message being sent to the timer daemon task. If the 01033 * priority of the timer daemon task (which is set using 01034 * configTIMER_TASK_PRIORITY in FreeRTOSConfig.h) is higher than the priority of 01035 * the currently running task (the task the interrupt interrupted) then 01036 * *pxHigherPriorityTaskWoken will be set to pdTRUE within 01037 * xTimerPendFunctionCallFromISR(), indicating that a context switch should be 01038 * requested before the interrupt exits. For that reason 01039 * *pxHigherPriorityTaskWoken must be initialised to pdFALSE. See the 01040 * example code below. 01041 * 01042 * @return pdPASS is returned if the message was successfully sent to the 01043 * timer daemon task, otherwise pdFALSE is returned. 01044 * 01045 * Example usage: 01046 * @verbatim 01047 * 01048 * // The callback function that will execute in the context of the daemon task. 01049 * // Note callback functions must all use this same prototype. 01050 * void vProcessInterface( void *pvParameter1, uint32_t ulParameter2 ) 01051 * { 01052 * BaseType_t xInterfaceToService; 01053 * 01054 * // The interface that requires servicing is passed in the second 01055 * // parameter. The first parameter is not used in this case. 01056 * xInterfaceToService = ( BaseType_t ) ulParameter2; 01057 * 01058 * // ...Perform the processing here... 01059 * } 01060 * 01061 * // An ISR that receives data packets from multiple interfaces 01062 * void vAnISR( void ) 01063 * { 01064 * BaseType_t xInterfaceToService, xHigherPriorityTaskWoken; 01065 * 01066 * // Query the hardware to determine which interface needs processing. 01067 * xInterfaceToService = prvCheckInterfaces(); 01068 * 01069 * // The actual processing is to be deferred to a task. Request the 01070 * // vProcessInterface() callback function is executed, passing in the 01071 * // number of the interface that needs processing. The interface to 01072 * // service is passed in the second parameter. The first parameter is 01073 * // not used in this case. 01074 * xHigherPriorityTaskWoken = pdFALSE; 01075 * xTimerPendFunctionCallFromISR( vProcessInterface, NULL, ( uint32_t ) xInterfaceToService, &xHigherPriorityTaskWoken ); 01076 * 01077 * // If xHigherPriorityTaskWoken is now set to pdTRUE then a context 01078 * // switch should be requested. The macro used is port specific and will 01079 * // be either portYIELD_FROM_ISR() or portEND_SWITCHING_ISR() - refer to 01080 * // the documentation page for the port being used. 01081 * portYIELD_FROM_ISR( xHigherPriorityTaskWoken ); 01082 * 01083 * } 01084 * @endverbatim 01085 */ 01086 BaseType_t xTimerPendFunctionCallFromISR( PendedFunction_t xFunctionToPend, void *pvParameter1, uint32_t ulParameter2, BaseType_t *pxHigherPriorityTaskWoken ); 01087 01088 /** 01089 * BaseType_t xTimerPendFunctionCall( PendedFunction_t xFunctionToPend, 01090 * void *pvParameter1, 01091 * uint32_t ulParameter2, 01092 * TickType_t xTicksToWait ); 01093 * 01094 * 01095 * Used to defer the execution of a function to the RTOS daemon task (the timer 01096 * service task, hence this function is implemented in timers.c and is prefixed 01097 * with 'Timer'). 01098 * 01099 * @param xFunctionToPend The function to execute from the timer service/ 01100 * daemon task. The function must conform to the PendedFunction_t 01101 * prototype. 01102 * 01103 * @param pvParameter1 The value of the callback function's first parameter. 01104 * The parameter has a void * type to allow it to be used to pass any type. 01105 * For example, unsigned longs can be cast to a void *, or the void * can be 01106 * used to point to a structure. 01107 * 01108 * @param ulParameter2 The value of the callback function's second parameter. 01109 * 01110 * @param xTicksToWait Calling this function will result in a message being 01111 * sent to the timer daemon task on a queue. xTicksToWait is the amount of 01112 * time the calling task should remain in the Blocked state (so not using any 01113 * processing time) for space to become available on the timer queue if the 01114 * queue is found to be full. 01115 * 01116 * @return pdPASS is returned if the message was successfully sent to the 01117 * timer daemon task, otherwise pdFALSE is returned. 01118 * 01119 */ 01120 BaseType_t xTimerPendFunctionCall( PendedFunction_t xFunctionToPend, void *pvParameter1, uint32_t ulParameter2, TickType_t xTicksToWait ); 01121 01122 /** 01123 * const char * const pcTimerGetTimerName( TimerHandle_t xTimer ); 01124 * 01125 * Returns the name that was assigned to a timer when the timer was created. 01126 * 01127 * @param xTimer The handle of the timer being queried. 01128 * 01129 * @return The name assigned to the timer specified by the xTimer parameter. 01130 */ 01131 const char * pcTimerGetTimerName( TimerHandle_t xTimer ); /*lint !e971 Unqualified char types are allowed for strings and single characters only. */ 01132 01133 /* 01134 * Functions beyond this part are not part of the public API and are intended 01135 * for use by the kernel only. 01136 */ 01137 BaseType_t xTimerCreateTimerTask( void ) PRIVILEGED_FUNCTION; 01138 BaseType_t xTimerGenericCommand( TimerHandle_t xTimer, const BaseType_t xCommandID, const TickType_t xOptionalValue, BaseType_t * const pxHigherPriorityTaskWoken, const TickType_t xTicksToWait ) PRIVILEGED_FUNCTION; 01139 01140 #ifdef __cplusplus 01141 } 01142 #endif 01143 #endif /* TIMERS_H */ 01144 01145 01146 01147
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