2 * FreeRTOS Kernel V10.6.2
3 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
5 * SPDX-License-Identifier: MIT
7 * Permission is hereby granted, free of charge, to any person obtaining a copy of
8 * this software and associated documentation files (the "Software"), to deal in
9 * the Software without restriction, including without limitation the rights to
10 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
11 * the Software, and to permit persons to whom the Software is furnished to do so,
12 * subject to the following conditions:
14 * The above copyright notice and this permission notice shall be included in all
15 * copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
19 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
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21 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 * https://www.FreeRTOS.org
25 * https://github.com/FreeRTOS
33 #ifndef INC_FREERTOS_H
34 #error "include FreeRTOS.h must appear in source files before include task.h"
45 /*-----------------------------------------------------------
46 * MACROS AND DEFINITIONS
47 *----------------------------------------------------------*/
50 * If tskKERNEL_VERSION_NUMBER ends with + it represents the version in development
51 * after the numbered release.
53 * The tskKERNEL_VERSION_MAJOR, tskKERNEL_VERSION_MINOR, tskKERNEL_VERSION_BUILD
54 * values will reflect the last released version number.
56 #define tskKERNEL_VERSION_NUMBER "V10.6.2"
57 #define tskKERNEL_VERSION_MAJOR 10
58 #define tskKERNEL_VERSION_MINOR 6
59 #define tskKERNEL_VERSION_BUILD 2
61 /* MPU region parameters passed in ulParameters
62 * of MemoryRegion_t struct. */
63 #define tskMPU_REGION_READ_ONLY ( 1UL << 0UL )
64 #define tskMPU_REGION_READ_WRITE ( 1UL << 1UL )
65 #define tskMPU_REGION_EXECUTE_NEVER ( 1UL << 2UL )
66 #define tskMPU_REGION_NORMAL_MEMORY ( 1UL << 3UL )
67 #define tskMPU_REGION_DEVICE_MEMORY ( 1UL << 4UL )
69 /* MPU region permissions stored in MPU settings to
70 * authorize access requests. */
71 #define tskMPU_READ_PERMISSION ( 1UL << 0UL )
72 #define tskMPU_WRITE_PERMISSION ( 1UL << 1UL )
74 /* The direct to task notification feature used to have only a single notification
75 * per task. Now there is an array of notifications per task that is dimensioned by
76 * configTASK_NOTIFICATION_ARRAY_ENTRIES. For backward compatibility, any use of the
77 * original direct to task notification defaults to using the first index in the
79 #define tskDEFAULT_INDEX_TO_NOTIFY ( 0 )
84 * Type by which tasks are referenced. For example, a call to xTaskCreate
85 * returns (via a pointer parameter) an TaskHandle_t variable that can then
86 * be used as a parameter to vTaskDelete to delete the task.
88 * \defgroup TaskHandle_t TaskHandle_t
91 struct tskTaskControlBlock; /* The old naming convention is used to prevent breaking kernel aware debuggers. */
92 typedef struct tskTaskControlBlock * TaskHandle_t;
95 * Defines the prototype to which the application task hook function must
98 typedef BaseType_t (* TaskHookFunction_t)( void * );
100 /* Task states returned by eTaskGetState. */
103 eRunning = 0, /* A task is querying the state of itself, so must be running. */
104 eReady, /* The task being queried is in a ready or pending ready list. */
105 eBlocked, /* The task being queried is in the Blocked state. */
106 eSuspended, /* The task being queried is in the Suspended state, or is in the Blocked state with an infinite time out. */
107 eDeleted, /* The task being queried has been deleted, but its TCB has not yet been freed. */
108 eInvalid /* Used as an 'invalid state' value. */
111 /* Actions that can be performed when vTaskNotify() is called. */
114 eNoAction = 0, /* Notify the task without updating its notify value. */
115 eSetBits, /* Set bits in the task's notification value. */
116 eIncrement, /* Increment the task's notification value. */
117 eSetValueWithOverwrite, /* Set the task's notification value to a specific value even if the previous value has not yet been read by the task. */
118 eSetValueWithoutOverwrite /* Set the task's notification value if the previous value has been read by the task. */
122 * Used internally only.
124 typedef struct xTIME_OUT
126 BaseType_t xOverflowCount;
127 TickType_t xTimeOnEntering;
131 * Defines the memory ranges allocated to the task when an MPU is used.
133 typedef struct xMEMORY_REGION
135 void * pvBaseAddress;
136 uint32_t ulLengthInBytes;
137 uint32_t ulParameters;
141 * Parameters required to create an MPU protected task.
143 typedef struct xTASK_PARAMETERS
145 TaskFunction_t pvTaskCode;
146 const char * pcName; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
147 configSTACK_DEPTH_TYPE usStackDepth;
149 UBaseType_t uxPriority;
150 StackType_t * puxStackBuffer;
151 MemoryRegion_t xRegions[ portNUM_CONFIGURABLE_REGIONS ];
152 #if ( ( portUSING_MPU_WRAPPERS == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
153 StaticTask_t * const pxTaskBuffer;
157 /* Used with the uxTaskGetSystemState() function to return the state of each task
159 typedef struct xTASK_STATUS
161 TaskHandle_t xHandle; /* The handle of the task to which the rest of the information in the structure relates. */
162 const char * pcTaskName; /* A pointer to the task's name. This value will be invalid if the task was deleted since the structure was populated! */ /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
163 UBaseType_t xTaskNumber; /* A number unique to the task. */
164 eTaskState eCurrentState; /* The state in which the task existed when the structure was populated. */
165 UBaseType_t uxCurrentPriority; /* The priority at which the task was running (may be inherited) when the structure was populated. */
166 UBaseType_t uxBasePriority; /* The priority to which the task will return if the task's current priority has been inherited to avoid unbounded priority inversion when obtaining a mutex. Only valid if configUSE_MUTEXES is defined as 1 in FreeRTOSConfig.h. */
167 configRUN_TIME_COUNTER_TYPE ulRunTimeCounter; /* The total run time allocated to the task so far, as defined by the run time stats clock. See https://www.FreeRTOS.org/rtos-run-time-stats.html. Only valid when configGENERATE_RUN_TIME_STATS is defined as 1 in FreeRTOSConfig.h. */
168 StackType_t * pxStackBase; /* Points to the lowest address of the task's stack area. */
169 #if ( ( portSTACK_GROWTH > 0 ) && ( configRECORD_STACK_HIGH_ADDRESS == 1 ) )
170 StackType_t * pxTopOfStack; /* Points to the top address of the task's stack area. */
171 StackType_t * pxEndOfStack; /* Points to the end address of the task's stack area. */
173 configSTACK_DEPTH_TYPE usStackHighWaterMark; /* The minimum amount of stack space that has remained for the task since the task was created. The closer this value is to zero the closer the task has come to overflowing its stack. */
176 /* Possible return values for eTaskConfirmSleepModeStatus(). */
179 eAbortSleep = 0, /* A task has been made ready or a context switch pended since portSUPPRESS_TICKS_AND_SLEEP() was called - abort entering a sleep mode. */
180 eStandardSleep, /* Enter a sleep mode that will not last any longer than the expected idle time. */
181 #if ( INCLUDE_vTaskSuspend == 1 )
182 eNoTasksWaitingTimeout /* No tasks are waiting for a timeout so it is safe to enter a sleep mode that can only be exited by an external interrupt. */
183 #endif /* INCLUDE_vTaskSuspend */
187 * Defines the priority used by the idle task. This must not be modified.
191 #define tskIDLE_PRIORITY ( ( UBaseType_t ) 0U )
196 * Macro for forcing a context switch.
198 * \defgroup taskYIELD taskYIELD
199 * \ingroup SchedulerControl
201 #define taskYIELD() portYIELD()
206 * Macro to mark the start of a critical code region. Preemptive context
207 * switches cannot occur when in a critical region.
209 * NOTE: This may alter the stack (depending on the portable implementation)
210 * so must be used with care!
212 * \defgroup taskENTER_CRITICAL taskENTER_CRITICAL
213 * \ingroup SchedulerControl
215 #define taskENTER_CRITICAL() portENTER_CRITICAL()
216 #define taskENTER_CRITICAL_FROM_ISR() portSET_INTERRUPT_MASK_FROM_ISR()
221 * Macro to mark the end of a critical code region. Preemptive context
222 * switches cannot occur when in a critical region.
224 * NOTE: This may alter the stack (depending on the portable implementation)
225 * so must be used with care!
227 * \defgroup taskEXIT_CRITICAL taskEXIT_CRITICAL
228 * \ingroup SchedulerControl
230 #define taskEXIT_CRITICAL() portEXIT_CRITICAL()
231 #define taskEXIT_CRITICAL_FROM_ISR( x ) portCLEAR_INTERRUPT_MASK_FROM_ISR( x )
236 * Macro to disable all maskable interrupts.
238 * \defgroup taskDISABLE_INTERRUPTS taskDISABLE_INTERRUPTS
239 * \ingroup SchedulerControl
241 #define taskDISABLE_INTERRUPTS() portDISABLE_INTERRUPTS()
246 * Macro to enable microcontroller interrupts.
248 * \defgroup taskENABLE_INTERRUPTS taskENABLE_INTERRUPTS
249 * \ingroup SchedulerControl
251 #define taskENABLE_INTERRUPTS() portENABLE_INTERRUPTS()
253 /* Definitions returned by xTaskGetSchedulerState(). taskSCHEDULER_SUSPENDED is
254 * 0 to generate more optimal code when configASSERT() is defined as the constant
255 * is used in assert() statements. */
256 #define taskSCHEDULER_SUSPENDED ( ( BaseType_t ) 0 )
257 #define taskSCHEDULER_NOT_STARTED ( ( BaseType_t ) 1 )
258 #define taskSCHEDULER_RUNNING ( ( BaseType_t ) 2 )
261 /*-----------------------------------------------------------
263 *----------------------------------------------------------*/
268 * BaseType_t xTaskCreate(
269 * TaskFunction_t pxTaskCode,
270 * const char *pcName,
271 * configSTACK_DEPTH_TYPE usStackDepth,
272 * void *pvParameters,
273 * UBaseType_t uxPriority,
274 * TaskHandle_t *pxCreatedTask
278 * Create a new task and add it to the list of tasks that are ready to run.
280 * Internally, within the FreeRTOS implementation, tasks use two blocks of
281 * memory. The first block is used to hold the task's data structures. The
282 * second block is used by the task as its stack. If a task is created using
283 * xTaskCreate() then both blocks of memory are automatically dynamically
284 * allocated inside the xTaskCreate() function. (see
285 * https://www.FreeRTOS.org/a00111.html). If a task is created using
286 * xTaskCreateStatic() then the application writer must provide the required
287 * memory. xTaskCreateStatic() therefore allows a task to be created without
288 * using any dynamic memory allocation.
290 * See xTaskCreateStatic() for a version that does not use any dynamic memory
293 * xTaskCreate() can only be used to create a task that has unrestricted
294 * access to the entire microcontroller memory map. Systems that include MPU
295 * support can alternatively create an MPU constrained task using
296 * xTaskCreateRestricted().
298 * @param pxTaskCode Pointer to the task entry function. Tasks
299 * must be implemented to never return (i.e. continuous loop).
301 * @param pcName A descriptive name for the task. This is mainly used to
302 * facilitate debugging. Max length defined by configMAX_TASK_NAME_LEN - default
305 * @param usStackDepth The size of the task stack specified as the number of
306 * variables the stack can hold - not the number of bytes. For example, if
307 * the stack is 16 bits wide and usStackDepth is defined as 100, 200 bytes
308 * will be allocated for stack storage.
310 * @param pvParameters Pointer that will be used as the parameter for the task
313 * @param uxPriority The priority at which the task should run. Systems that
314 * include MPU support can optionally create tasks in a privileged (system)
315 * mode by setting bit portPRIVILEGE_BIT of the priority parameter. For
316 * example, to create a privileged task at priority 2 the uxPriority parameter
317 * should be set to ( 2 | portPRIVILEGE_BIT ).
319 * @param pxCreatedTask Used to pass back a handle by which the created task
322 * @return pdPASS if the task was successfully created and added to a ready
323 * list, otherwise an error code defined in the file projdefs.h
327 * // Task to be created.
328 * void vTaskCode( void * pvParameters )
332 * // Task code goes here.
336 * // Function that creates a task.
337 * void vOtherFunction( void )
339 * static uint8_t ucParameterToPass;
340 * TaskHandle_t xHandle = NULL;
342 * // Create the task, storing the handle. Note that the passed parameter ucParameterToPass
343 * // must exist for the lifetime of the task, so in this case is declared static. If it was just an
344 * // an automatic stack variable it might no longer exist, or at least have been corrupted, by the time
345 * // the new task attempts to access it.
346 * xTaskCreate( vTaskCode, "NAME", STACK_SIZE, &ucParameterToPass, tskIDLE_PRIORITY, &xHandle );
347 * configASSERT( xHandle );
349 * // Use the handle to delete the task.
350 * if( xHandle != NULL )
352 * vTaskDelete( xHandle );
356 * \defgroup xTaskCreate xTaskCreate
359 #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
360 BaseType_t xTaskCreate( TaskFunction_t pxTaskCode,
361 const char * const pcName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
362 const configSTACK_DEPTH_TYPE usStackDepth,
363 void * const pvParameters,
364 UBaseType_t uxPriority,
365 TaskHandle_t * const pxCreatedTask ) PRIVILEGED_FUNCTION;
371 * TaskHandle_t xTaskCreateStatic( TaskFunction_t pxTaskCode,
372 * const char *pcName,
373 * uint32_t ulStackDepth,
374 * void *pvParameters,
375 * UBaseType_t uxPriority,
376 * StackType_t *puxStackBuffer,
377 * StaticTask_t *pxTaskBuffer );
380 * Create a new task and add it to the list of tasks that are ready to run.
382 * Internally, within the FreeRTOS implementation, tasks use two blocks of
383 * memory. The first block is used to hold the task's data structures. The
384 * second block is used by the task as its stack. If a task is created using
385 * xTaskCreate() then both blocks of memory are automatically dynamically
386 * allocated inside the xTaskCreate() function. (see
387 * https://www.FreeRTOS.org/a00111.html). If a task is created using
388 * xTaskCreateStatic() then the application writer must provide the required
389 * memory. xTaskCreateStatic() therefore allows a task to be created without
390 * using any dynamic memory allocation.
392 * @param pxTaskCode Pointer to the task entry function. Tasks
393 * must be implemented to never return (i.e. continuous loop).
395 * @param pcName A descriptive name for the task. This is mainly used to
396 * facilitate debugging. The maximum length of the string is defined by
397 * configMAX_TASK_NAME_LEN in FreeRTOSConfig.h.
399 * @param ulStackDepth The size of the task stack specified as the number of
400 * variables the stack can hold - not the number of bytes. For example, if
401 * the stack is 32-bits wide and ulStackDepth is defined as 100 then 400 bytes
402 * will be allocated for stack storage.
404 * @param pvParameters Pointer that will be used as the parameter for the task
407 * @param uxPriority The priority at which the task will run.
409 * @param puxStackBuffer Must point to a StackType_t array that has at least
410 * ulStackDepth indexes - the array will then be used as the task's stack,
411 * removing the need for the stack to be allocated dynamically.
413 * @param pxTaskBuffer Must point to a variable of type StaticTask_t, which will
414 * then be used to hold the task's data structures, removing the need for the
415 * memory to be allocated dynamically.
417 * @return If neither puxStackBuffer nor pxTaskBuffer are NULL, then the task
418 * will be created and a handle to the created task is returned. If either
419 * puxStackBuffer or pxTaskBuffer are NULL then the task will not be created and
425 * // Dimensions of the buffer that the task being created will use as its stack.
426 * // NOTE: This is the number of words the stack will hold, not the number of
427 * // bytes. For example, if each stack item is 32-bits, and this is set to 100,
428 * // then 400 bytes (100 * 32-bits) will be allocated.
429 #define STACK_SIZE 200
431 * // Structure that will hold the TCB of the task being created.
432 * StaticTask_t xTaskBuffer;
434 * // Buffer that the task being created will use as its stack. Note this is
435 * // an array of StackType_t variables. The size of StackType_t is dependent on
437 * StackType_t xStack[ STACK_SIZE ];
439 * // Function that implements the task being created.
440 * void vTaskCode( void * pvParameters )
442 * // The parameter value is expected to be 1 as 1 is passed in the
443 * // pvParameters value in the call to xTaskCreateStatic().
444 * configASSERT( ( uint32_t ) pvParameters == 1UL );
448 * // Task code goes here.
452 * // Function that creates a task.
453 * void vOtherFunction( void )
455 * TaskHandle_t xHandle = NULL;
457 * // Create the task without using any dynamic memory allocation.
458 * xHandle = xTaskCreateStatic(
459 * vTaskCode, // Function that implements the task.
460 * "NAME", // Text name for the task.
461 * STACK_SIZE, // Stack size in words, not bytes.
462 * ( void * ) 1, // Parameter passed into the task.
463 * tskIDLE_PRIORITY,// Priority at which the task is created.
464 * xStack, // Array to use as the task's stack.
465 * &xTaskBuffer ); // Variable to hold the task's data structure.
467 * // puxStackBuffer and pxTaskBuffer were not NULL, so the task will have
468 * // been created, and xHandle will be the task's handle. Use the handle
469 * // to suspend the task.
470 * vTaskSuspend( xHandle );
473 * \defgroup xTaskCreateStatic xTaskCreateStatic
476 #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
477 TaskHandle_t xTaskCreateStatic( TaskFunction_t pxTaskCode,
478 const char * const pcName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
479 const uint32_t ulStackDepth,
480 void * const pvParameters,
481 UBaseType_t uxPriority,
482 StackType_t * const puxStackBuffer,
483 StaticTask_t * const pxTaskBuffer ) PRIVILEGED_FUNCTION;
484 #endif /* configSUPPORT_STATIC_ALLOCATION */
489 * BaseType_t xTaskCreateRestricted( TaskParameters_t *pxTaskDefinition, TaskHandle_t *pxCreatedTask );
492 * Only available when configSUPPORT_DYNAMIC_ALLOCATION is set to 1.
494 * xTaskCreateRestricted() should only be used in systems that include an MPU
497 * Create a new task and add it to the list of tasks that are ready to run.
498 * The function parameters define the memory regions and associated access
499 * permissions allocated to the task.
501 * See xTaskCreateRestrictedStatic() for a version that does not use any
502 * dynamic memory allocation.
504 * @param pxTaskDefinition Pointer to a structure that contains a member
505 * for each of the normal xTaskCreate() parameters (see the xTaskCreate() API
506 * documentation) plus an optional stack buffer and the memory region
509 * @param pxCreatedTask Used to pass back a handle by which the created task
512 * @return pdPASS if the task was successfully created and added to a ready
513 * list, otherwise an error code defined in the file projdefs.h
517 * // Create an TaskParameters_t structure that defines the task to be created.
518 * static const TaskParameters_t xCheckTaskParameters =
520 * vATask, // pvTaskCode - the function that implements the task.
521 * "ATask", // pcName - just a text name for the task to assist debugging.
522 * 100, // usStackDepth - the stack size DEFINED IN WORDS.
523 * NULL, // pvParameters - passed into the task function as the function parameters.
524 * ( 1UL | portPRIVILEGE_BIT ),// uxPriority - task priority, set the portPRIVILEGE_BIT if the task should run in a privileged state.
525 * cStackBuffer,// puxStackBuffer - the buffer to be used as the task stack.
527 * // xRegions - Allocate up to three separate memory regions for access by
528 * // the task, with appropriate access permissions. Different processors have
529 * // different memory alignment requirements - refer to the FreeRTOS documentation
530 * // for full information.
532 * // Base address Length Parameters
533 * { cReadWriteArray, 32, portMPU_REGION_READ_WRITE },
534 * { cReadOnlyArray, 32, portMPU_REGION_READ_ONLY },
535 * { cPrivilegedOnlyAccessArray, 128, portMPU_REGION_PRIVILEGED_READ_WRITE }
541 * TaskHandle_t xHandle;
543 * // Create a task from the const structure defined above. The task handle
544 * // is requested (the second parameter is not NULL) but in this case just for
545 * // demonstration purposes as its not actually used.
546 * xTaskCreateRestricted( &xRegTest1Parameters, &xHandle );
548 * // Start the scheduler.
549 * vTaskStartScheduler();
551 * // Will only get here if there was insufficient memory to create the idle
552 * // and/or timer task.
556 * \defgroup xTaskCreateRestricted xTaskCreateRestricted
559 #if ( portUSING_MPU_WRAPPERS == 1 )
560 BaseType_t xTaskCreateRestricted( const TaskParameters_t * const pxTaskDefinition,
561 TaskHandle_t * pxCreatedTask ) PRIVILEGED_FUNCTION;
567 * BaseType_t xTaskCreateRestrictedStatic( TaskParameters_t *pxTaskDefinition, TaskHandle_t *pxCreatedTask );
570 * Only available when configSUPPORT_STATIC_ALLOCATION is set to 1.
572 * xTaskCreateRestrictedStatic() should only be used in systems that include an
573 * MPU implementation.
575 * Internally, within the FreeRTOS implementation, tasks use two blocks of
576 * memory. The first block is used to hold the task's data structures. The
577 * second block is used by the task as its stack. If a task is created using
578 * xTaskCreateRestricted() then the stack is provided by the application writer,
579 * and the memory used to hold the task's data structure is automatically
580 * dynamically allocated inside the xTaskCreateRestricted() function. If a task
581 * is created using xTaskCreateRestrictedStatic() then the application writer
582 * must provide the memory used to hold the task's data structures too.
583 * xTaskCreateRestrictedStatic() therefore allows a memory protected task to be
584 * created without using any dynamic memory allocation.
586 * @param pxTaskDefinition Pointer to a structure that contains a member
587 * for each of the normal xTaskCreate() parameters (see the xTaskCreate() API
588 * documentation) plus an optional stack buffer and the memory region
589 * definitions. If configSUPPORT_STATIC_ALLOCATION is set to 1 the structure
590 * contains an additional member, which is used to point to a variable of type
591 * StaticTask_t - which is then used to hold the task's data structure.
593 * @param pxCreatedTask Used to pass back a handle by which the created task
596 * @return pdPASS if the task was successfully created and added to a ready
597 * list, otherwise an error code defined in the file projdefs.h
601 * // Create an TaskParameters_t structure that defines the task to be created.
602 * // The StaticTask_t variable is only included in the structure when
603 * // configSUPPORT_STATIC_ALLOCATION is set to 1. The PRIVILEGED_DATA macro can
604 * // be used to force the variable into the RTOS kernel's privileged data area.
605 * static PRIVILEGED_DATA StaticTask_t xTaskBuffer;
606 * static const TaskParameters_t xCheckTaskParameters =
608 * vATask, // pvTaskCode - the function that implements the task.
609 * "ATask", // pcName - just a text name for the task to assist debugging.
610 * 100, // usStackDepth - the stack size DEFINED IN WORDS.
611 * NULL, // pvParameters - passed into the task function as the function parameters.
612 * ( 1UL | portPRIVILEGE_BIT ),// uxPriority - task priority, set the portPRIVILEGE_BIT if the task should run in a privileged state.
613 * cStackBuffer,// puxStackBuffer - the buffer to be used as the task stack.
615 * // xRegions - Allocate up to three separate memory regions for access by
616 * // the task, with appropriate access permissions. Different processors have
617 * // different memory alignment requirements - refer to the FreeRTOS documentation
618 * // for full information.
620 * // Base address Length Parameters
621 * { cReadWriteArray, 32, portMPU_REGION_READ_WRITE },
622 * { cReadOnlyArray, 32, portMPU_REGION_READ_ONLY },
623 * { cPrivilegedOnlyAccessArray, 128, portMPU_REGION_PRIVILEGED_READ_WRITE }
626 * &xTaskBuffer; // Holds the task's data structure.
631 * TaskHandle_t xHandle;
633 * // Create a task from the const structure defined above. The task handle
634 * // is requested (the second parameter is not NULL) but in this case just for
635 * // demonstration purposes as its not actually used.
636 * xTaskCreateRestrictedStatic( &xRegTest1Parameters, &xHandle );
638 * // Start the scheduler.
639 * vTaskStartScheduler();
641 * // Will only get here if there was insufficient memory to create the idle
642 * // and/or timer task.
646 * \defgroup xTaskCreateRestrictedStatic xTaskCreateRestrictedStatic
649 #if ( ( portUSING_MPU_WRAPPERS == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
650 BaseType_t xTaskCreateRestrictedStatic( const TaskParameters_t * const pxTaskDefinition,
651 TaskHandle_t * pxCreatedTask ) PRIVILEGED_FUNCTION;
657 * void vTaskAllocateMPURegions( TaskHandle_t xTask, const MemoryRegion_t * const pxRegions );
660 * Memory regions are assigned to a restricted task when the task is created by
661 * a call to xTaskCreateRestricted(). These regions can be redefined using
662 * vTaskAllocateMPURegions().
664 * @param xTask The handle of the task being updated.
666 * @param[in] pxRegions A pointer to a MemoryRegion_t structure that contains the
667 * new memory region definitions.
671 * // Define an array of MemoryRegion_t structures that configures an MPU region
672 * // allowing read/write access for 1024 bytes starting at the beginning of the
673 * // ucOneKByte array. The other two of the maximum 3 definable regions are
674 * // unused so set to zero.
675 * static const MemoryRegion_t xAltRegions[ portNUM_CONFIGURABLE_REGIONS ] =
677 * // Base address Length Parameters
678 * { ucOneKByte, 1024, portMPU_REGION_READ_WRITE },
683 * void vATask( void *pvParameters )
685 * // This task was created such that it has access to certain regions of
686 * // memory as defined by the MPU configuration. At some point it is
687 * // desired that these MPU regions are replaced with that defined in the
688 * // xAltRegions const struct above. Use a call to vTaskAllocateMPURegions()
689 * // for this purpose. NULL is used as the task handle to indicate that this
690 * // function should modify the MPU regions of the calling task.
691 * vTaskAllocateMPURegions( NULL, xAltRegions );
693 * // Now the task can continue its function, but from this point on can only
694 * // access its stack and the ucOneKByte array (unless any other statically
695 * // defined or shared regions have been declared elsewhere).
698 * \defgroup vTaskAllocateMPURegions vTaskAllocateMPURegions
701 void vTaskAllocateMPURegions( TaskHandle_t xTask,
702 const MemoryRegion_t * const pxRegions ) PRIVILEGED_FUNCTION;
707 * void vTaskDelete( TaskHandle_t xTaskToDelete );
710 * INCLUDE_vTaskDelete must be defined as 1 for this function to be available.
711 * See the configuration section for more information.
713 * Remove a task from the RTOS real time kernel's management. The task being
714 * deleted will be removed from all ready, blocked, suspended and event lists.
716 * NOTE: The idle task is responsible for freeing the kernel allocated
717 * memory from tasks that have been deleted. It is therefore important that
718 * the idle task is not starved of microcontroller processing time if your
719 * application makes any calls to vTaskDelete (). Memory allocated by the
720 * task code is not automatically freed, and should be freed before the task
723 * See the demo application file death.c for sample code that utilises
726 * @param xTaskToDelete The handle of the task to be deleted. Passing NULL will
727 * cause the calling task to be deleted.
731 * void vOtherFunction( void )
733 * TaskHandle_t xHandle;
735 * // Create the task, storing the handle.
736 * xTaskCreate( vTaskCode, "NAME", STACK_SIZE, NULL, tskIDLE_PRIORITY, &xHandle );
738 * // Use the handle to delete the task.
739 * vTaskDelete( xHandle );
742 * \defgroup vTaskDelete vTaskDelete
745 void vTaskDelete( TaskHandle_t xTaskToDelete ) PRIVILEGED_FUNCTION;
747 /*-----------------------------------------------------------
749 *----------------------------------------------------------*/
754 * void vTaskDelay( const TickType_t xTicksToDelay );
757 * Delay a task for a given number of ticks. The actual time that the
758 * task remains blocked depends on the tick rate. The constant
759 * portTICK_PERIOD_MS can be used to calculate real time from the tick
760 * rate - with the resolution of one tick period.
762 * INCLUDE_vTaskDelay must be defined as 1 for this function to be available.
763 * See the configuration section for more information.
766 * vTaskDelay() specifies a time at which the task wishes to unblock relative to
767 * the time at which vTaskDelay() is called. For example, specifying a block
768 * period of 100 ticks will cause the task to unblock 100 ticks after
769 * vTaskDelay() is called. vTaskDelay() does not therefore provide a good method
770 * of controlling the frequency of a periodic task as the path taken through the
771 * code, as well as other task and interrupt activity, will affect the frequency
772 * at which vTaskDelay() gets called and therefore the time at which the task
773 * next executes. See xTaskDelayUntil() for an alternative API function designed
774 * to facilitate fixed frequency execution. It does this by specifying an
775 * absolute time (rather than a relative time) at which the calling task should
778 * @param xTicksToDelay The amount of time, in tick periods, that
779 * the calling task should block.
783 * void vTaskFunction( void * pvParameters )
785 * // Block for 500ms.
786 * const TickType_t xDelay = 500 / portTICK_PERIOD_MS;
790 * // Simply toggle the LED every 500ms, blocking between each toggle.
792 * vTaskDelay( xDelay );
796 * \defgroup vTaskDelay vTaskDelay
799 void vTaskDelay( const TickType_t xTicksToDelay ) PRIVILEGED_FUNCTION;
804 * BaseType_t xTaskDelayUntil( TickType_t *pxPreviousWakeTime, const TickType_t xTimeIncrement );
807 * INCLUDE_xTaskDelayUntil must be defined as 1 for this function to be available.
808 * See the configuration section for more information.
810 * Delay a task until a specified time. This function can be used by periodic
811 * tasks to ensure a constant execution frequency.
813 * This function differs from vTaskDelay () in one important aspect: vTaskDelay () will
814 * cause a task to block for the specified number of ticks from the time vTaskDelay () is
815 * called. It is therefore difficult to use vTaskDelay () by itself to generate a fixed
816 * execution frequency as the time between a task starting to execute and that task
817 * calling vTaskDelay () may not be fixed [the task may take a different path though the
818 * code between calls, or may get interrupted or preempted a different number of times
819 * each time it executes].
821 * Whereas vTaskDelay () specifies a wake time relative to the time at which the function
822 * is called, xTaskDelayUntil () specifies the absolute (exact) time at which it wishes to
825 * The macro pdMS_TO_TICKS() can be used to calculate the number of ticks from a
826 * time specified in milliseconds with a resolution of one tick period.
828 * @param pxPreviousWakeTime Pointer to a variable that holds the time at which the
829 * task was last unblocked. The variable must be initialised with the current time
830 * prior to its first use (see the example below). Following this the variable is
831 * automatically updated within xTaskDelayUntil ().
833 * @param xTimeIncrement The cycle time period. The task will be unblocked at
834 * time *pxPreviousWakeTime + xTimeIncrement. Calling xTaskDelayUntil with the
835 * same xTimeIncrement parameter value will cause the task to execute with
836 * a fixed interface period.
838 * @return Value which can be used to check whether the task was actually delayed.
839 * Will be pdTRUE if the task way delayed and pdFALSE otherwise. A task will not
840 * be delayed if the next expected wake time is in the past.
844 * // Perform an action every 10 ticks.
845 * void vTaskFunction( void * pvParameters )
847 * TickType_t xLastWakeTime;
848 * const TickType_t xFrequency = 10;
849 * BaseType_t xWasDelayed;
851 * // Initialise the xLastWakeTime variable with the current time.
852 * xLastWakeTime = xTaskGetTickCount ();
855 * // Wait for the next cycle.
856 * xWasDelayed = xTaskDelayUntil( &xLastWakeTime, xFrequency );
858 * // Perform action here. xWasDelayed value can be used to determine
859 * // whether a deadline was missed if the code here took too long.
863 * \defgroup xTaskDelayUntil xTaskDelayUntil
866 BaseType_t xTaskDelayUntil( TickType_t * const pxPreviousWakeTime,
867 const TickType_t xTimeIncrement ) PRIVILEGED_FUNCTION;
870 * vTaskDelayUntil() is the older version of xTaskDelayUntil() and does not
873 #define vTaskDelayUntil( pxPreviousWakeTime, xTimeIncrement ) \
875 ( void ) xTaskDelayUntil( ( pxPreviousWakeTime ), ( xTimeIncrement ) ); \
882 * BaseType_t xTaskAbortDelay( TaskHandle_t xTask );
885 * INCLUDE_xTaskAbortDelay must be defined as 1 in FreeRTOSConfig.h for this
886 * function to be available.
888 * A task will enter the Blocked state when it is waiting for an event. The
889 * event it is waiting for can be a temporal event (waiting for a time), such
890 * as when vTaskDelay() is called, or an event on an object, such as when
891 * xQueueReceive() or ulTaskNotifyTake() is called. If the handle of a task
892 * that is in the Blocked state is used in a call to xTaskAbortDelay() then the
893 * task will leave the Blocked state, and return from whichever function call
894 * placed the task into the Blocked state.
896 * There is no 'FromISR' version of this function as an interrupt would need to
897 * know which object a task was blocked on in order to know which actions to
898 * take. For example, if the task was blocked on a queue the interrupt handler
899 * would then need to know if the queue was locked.
901 * @param xTask The handle of the task to remove from the Blocked state.
903 * @return If the task referenced by xTask was not in the Blocked state then
904 * pdFAIL is returned. Otherwise pdPASS is returned.
906 * \defgroup xTaskAbortDelay xTaskAbortDelay
909 BaseType_t xTaskAbortDelay( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
914 * UBaseType_t uxTaskPriorityGet( const TaskHandle_t xTask );
917 * INCLUDE_uxTaskPriorityGet must be defined as 1 for this function to be available.
918 * See the configuration section for more information.
920 * Obtain the priority of any task.
922 * @param xTask Handle of the task to be queried. Passing a NULL
923 * handle results in the priority of the calling task being returned.
925 * @return The priority of xTask.
929 * void vAFunction( void )
931 * TaskHandle_t xHandle;
933 * // Create a task, storing the handle.
934 * xTaskCreate( vTaskCode, "NAME", STACK_SIZE, NULL, tskIDLE_PRIORITY, &xHandle );
938 * // Use the handle to obtain the priority of the created task.
939 * // It was created with tskIDLE_PRIORITY, but may have changed
941 * if( uxTaskPriorityGet( xHandle ) != tskIDLE_PRIORITY )
943 * // The task has changed it's priority.
948 * // Is our priority higher than the created task?
949 * if( uxTaskPriorityGet( xHandle ) < uxTaskPriorityGet( NULL ) )
951 * // Our priority (obtained using NULL handle) is higher.
955 * \defgroup uxTaskPriorityGet uxTaskPriorityGet
958 UBaseType_t uxTaskPriorityGet( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
963 * UBaseType_t uxTaskPriorityGetFromISR( const TaskHandle_t xTask );
966 * A version of uxTaskPriorityGet() that can be used from an ISR.
968 UBaseType_t uxTaskPriorityGetFromISR( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
973 * eTaskState eTaskGetState( TaskHandle_t xTask );
976 * INCLUDE_eTaskGetState must be defined as 1 for this function to be available.
977 * See the configuration section for more information.
979 * Obtain the state of any task. States are encoded by the eTaskState
982 * @param xTask Handle of the task to be queried.
984 * @return The state of xTask at the time the function was called. Note the
985 * state of the task might change between the function being called, and the
986 * functions return value being tested by the calling task.
988 eTaskState eTaskGetState( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
993 * void vTaskGetInfo( TaskHandle_t xTask, TaskStatus_t *pxTaskStatus, BaseType_t xGetFreeStackSpace, eTaskState eState );
996 * configUSE_TRACE_FACILITY must be defined as 1 for this function to be
997 * available. See the configuration section for more information.
999 * Populates a TaskStatus_t structure with information about a task.
1001 * @param xTask Handle of the task being queried. If xTask is NULL then
1002 * information will be returned about the calling task.
1004 * @param pxTaskStatus A pointer to the TaskStatus_t structure that will be
1005 * filled with information about the task referenced by the handle passed using
1006 * the xTask parameter.
1008 * @param xGetFreeStackSpace The TaskStatus_t structure contains a member to report
1009 * the stack high water mark of the task being queried. Calculating the stack
1010 * high water mark takes a relatively long time, and can make the system
1011 * temporarily unresponsive - so the xGetFreeStackSpace parameter is provided to
1012 * allow the high water mark checking to be skipped. The high watermark value
1013 * will only be written to the TaskStatus_t structure if xGetFreeStackSpace is
1014 * not set to pdFALSE;
1016 * @param eState The TaskStatus_t structure contains a member to report the
1017 * state of the task being queried. Obtaining the task state is not as fast as
1018 * a simple assignment - so the eState parameter is provided to allow the state
1019 * information to be omitted from the TaskStatus_t structure. To obtain state
1020 * information then set eState to eInvalid - otherwise the value passed in
1021 * eState will be reported as the task state in the TaskStatus_t structure.
1025 * void vAFunction( void )
1027 * TaskHandle_t xHandle;
1028 * TaskStatus_t xTaskDetails;
1030 * // Obtain the handle of a task from its name.
1031 * xHandle = xTaskGetHandle( "Task_Name" );
1033 * // Check the handle is not NULL.
1034 * configASSERT( xHandle );
1036 * // Use the handle to obtain further information about the task.
1037 * vTaskGetInfo( xHandle,
1039 * pdTRUE, // Include the high water mark in xTaskDetails.
1040 * eInvalid ); // Include the task state in xTaskDetails.
1043 * \defgroup vTaskGetInfo vTaskGetInfo
1046 void vTaskGetInfo( TaskHandle_t xTask,
1047 TaskStatus_t * pxTaskStatus,
1048 BaseType_t xGetFreeStackSpace,
1049 eTaskState eState ) PRIVILEGED_FUNCTION;
1054 * void vTaskPrioritySet( TaskHandle_t xTask, UBaseType_t uxNewPriority );
1057 * INCLUDE_vTaskPrioritySet must be defined as 1 for this function to be available.
1058 * See the configuration section for more information.
1060 * Set the priority of any task.
1062 * A context switch will occur before the function returns if the priority
1063 * being set is higher than the currently executing task.
1065 * @param xTask Handle to the task for which the priority is being set.
1066 * Passing a NULL handle results in the priority of the calling task being set.
1068 * @param uxNewPriority The priority to which the task will be set.
1072 * void vAFunction( void )
1074 * TaskHandle_t xHandle;
1076 * // Create a task, storing the handle.
1077 * xTaskCreate( vTaskCode, "NAME", STACK_SIZE, NULL, tskIDLE_PRIORITY, &xHandle );
1081 * // Use the handle to raise the priority of the created task.
1082 * vTaskPrioritySet( xHandle, tskIDLE_PRIORITY + 1 );
1086 * // Use a NULL handle to raise our priority to the same value.
1087 * vTaskPrioritySet( NULL, tskIDLE_PRIORITY + 1 );
1090 * \defgroup vTaskPrioritySet vTaskPrioritySet
1093 void vTaskPrioritySet( TaskHandle_t xTask,
1094 UBaseType_t uxNewPriority ) PRIVILEGED_FUNCTION;
1099 * void vTaskSuspend( TaskHandle_t xTaskToSuspend );
1102 * INCLUDE_vTaskSuspend must be defined as 1 for this function to be available.
1103 * See the configuration section for more information.
1105 * Suspend any task. When suspended a task will never get any microcontroller
1106 * processing time, no matter what its priority.
1108 * Calls to vTaskSuspend are not accumulative -
1109 * i.e. calling vTaskSuspend () twice on the same task still only requires one
1110 * call to vTaskResume () to ready the suspended task.
1112 * @param xTaskToSuspend Handle to the task being suspended. Passing a NULL
1113 * handle will cause the calling task to be suspended.
1117 * void vAFunction( void )
1119 * TaskHandle_t xHandle;
1121 * // Create a task, storing the handle.
1122 * xTaskCreate( vTaskCode, "NAME", STACK_SIZE, NULL, tskIDLE_PRIORITY, &xHandle );
1126 * // Use the handle to suspend the created task.
1127 * vTaskSuspend( xHandle );
1131 * // The created task will not run during this period, unless
1132 * // another task calls vTaskResume( xHandle ).
1137 * // Suspend ourselves.
1138 * vTaskSuspend( NULL );
1140 * // We cannot get here unless another task calls vTaskResume
1141 * // with our handle as the parameter.
1144 * \defgroup vTaskSuspend vTaskSuspend
1147 void vTaskSuspend( TaskHandle_t xTaskToSuspend ) PRIVILEGED_FUNCTION;
1152 * void vTaskResume( TaskHandle_t xTaskToResume );
1155 * INCLUDE_vTaskSuspend must be defined as 1 for this function to be available.
1156 * See the configuration section for more information.
1158 * Resumes a suspended task.
1160 * A task that has been suspended by one or more calls to vTaskSuspend ()
1161 * will be made available for running again by a single call to
1164 * @param xTaskToResume Handle to the task being readied.
1168 * void vAFunction( void )
1170 * TaskHandle_t xHandle;
1172 * // Create a task, storing the handle.
1173 * xTaskCreate( vTaskCode, "NAME", STACK_SIZE, NULL, tskIDLE_PRIORITY, &xHandle );
1177 * // Use the handle to suspend the created task.
1178 * vTaskSuspend( xHandle );
1182 * // The created task will not run during this period, unless
1183 * // another task calls vTaskResume( xHandle ).
1188 * // Resume the suspended task ourselves.
1189 * vTaskResume( xHandle );
1191 * // The created task will once again get microcontroller processing
1192 * // time in accordance with its priority within the system.
1195 * \defgroup vTaskResume vTaskResume
1198 void vTaskResume( TaskHandle_t xTaskToResume ) PRIVILEGED_FUNCTION;
1203 * void xTaskResumeFromISR( TaskHandle_t xTaskToResume );
1206 * INCLUDE_xTaskResumeFromISR must be defined as 1 for this function to be
1207 * available. See the configuration section for more information.
1209 * An implementation of vTaskResume() that can be called from within an ISR.
1211 * A task that has been suspended by one or more calls to vTaskSuspend ()
1212 * will be made available for running again by a single call to
1213 * xTaskResumeFromISR ().
1215 * xTaskResumeFromISR() should not be used to synchronise a task with an
1216 * interrupt if there is a chance that the interrupt could arrive prior to the
1217 * task being suspended - as this can lead to interrupts being missed. Use of a
1218 * semaphore as a synchronisation mechanism would avoid this eventuality.
1220 * @param xTaskToResume Handle to the task being readied.
1222 * @return pdTRUE if resuming the task should result in a context switch,
1223 * otherwise pdFALSE. This is used by the ISR to determine if a context switch
1224 * may be required following the ISR.
1226 * \defgroup vTaskResumeFromISR vTaskResumeFromISR
1229 BaseType_t xTaskResumeFromISR( TaskHandle_t xTaskToResume ) PRIVILEGED_FUNCTION;
1231 /*-----------------------------------------------------------
1233 *----------------------------------------------------------*/
1238 * void vTaskStartScheduler( void );
1241 * Starts the real time kernel tick processing. After calling the kernel
1242 * has control over which tasks are executed and when.
1244 * See the demo application file main.c for an example of creating
1245 * tasks and starting the kernel.
1249 * void vAFunction( void )
1251 * // Create at least one task before starting the kernel.
1252 * xTaskCreate( vTaskCode, "NAME", STACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
1254 * // Start the real time kernel with preemption.
1255 * vTaskStartScheduler ();
1257 * // Will not get here unless a task calls vTaskEndScheduler ()
1261 * \defgroup vTaskStartScheduler vTaskStartScheduler
1262 * \ingroup SchedulerControl
1264 void vTaskStartScheduler( void ) PRIVILEGED_FUNCTION;
1269 * void vTaskEndScheduler( void );
1272 * NOTE: At the time of writing only the x86 real mode port, which runs on a PC
1273 * in place of DOS, implements this function.
1275 * Stops the real time kernel tick. All created tasks will be automatically
1276 * deleted and multitasking (either preemptive or cooperative) will
1277 * stop. Execution then resumes from the point where vTaskStartScheduler ()
1278 * was called, as if vTaskStartScheduler () had just returned.
1280 * See the demo application file main. c in the demo/PC directory for an
1281 * example that uses vTaskEndScheduler ().
1283 * vTaskEndScheduler () requires an exit function to be defined within the
1284 * portable layer (see vPortEndScheduler () in port. c for the PC port). This
1285 * performs hardware specific operations such as stopping the kernel tick.
1287 * vTaskEndScheduler () will cause all of the resources allocated by the
1288 * kernel to be freed - but will not free resources allocated by application
1293 * void vTaskCode( void * pvParameters )
1297 * // Task code goes here.
1299 * // At some point we want to end the real time kernel processing
1301 * vTaskEndScheduler ();
1305 * void vAFunction( void )
1307 * // Create at least one task before starting the kernel.
1308 * xTaskCreate( vTaskCode, "NAME", STACK_SIZE, NULL, tskIDLE_PRIORITY, NULL );
1310 * // Start the real time kernel with preemption.
1311 * vTaskStartScheduler ();
1313 * // Will only get here when the vTaskCode () task has called
1314 * // vTaskEndScheduler (). When we get here we are back to single task
1319 * \defgroup vTaskEndScheduler vTaskEndScheduler
1320 * \ingroup SchedulerControl
1322 void vTaskEndScheduler( void ) PRIVILEGED_FUNCTION;
1327 * void vTaskSuspendAll( void );
1330 * Suspends the scheduler without disabling interrupts. Context switches will
1331 * not occur while the scheduler is suspended.
1333 * After calling vTaskSuspendAll () the calling task will continue to execute
1334 * without risk of being swapped out until a call to xTaskResumeAll () has been
1337 * API functions that have the potential to cause a context switch (for example,
1338 * xTaskDelayUntil(), xQueueSend(), etc.) must not be called while the scheduler
1343 * void vTask1( void * pvParameters )
1347 * // Task code goes here.
1351 * // At some point the task wants to perform a long operation during
1352 * // which it does not want to get swapped out. It cannot use
1353 * // taskENTER_CRITICAL ()/taskEXIT_CRITICAL () as the length of the
1354 * // operation may cause interrupts to be missed - including the
1357 * // Prevent the real time kernel swapping out the task.
1358 * vTaskSuspendAll ();
1360 * // Perform the operation here. There is no need to use critical
1361 * // sections as we have all the microcontroller processing time.
1362 * // During this time interrupts will still operate and the kernel
1363 * // tick count will be maintained.
1367 * // The operation is complete. Restart the kernel.
1368 * xTaskResumeAll ();
1372 * \defgroup vTaskSuspendAll vTaskSuspendAll
1373 * \ingroup SchedulerControl
1375 void vTaskSuspendAll( void ) PRIVILEGED_FUNCTION;
1380 * BaseType_t xTaskResumeAll( void );
1383 * Resumes scheduler activity after it was suspended by a call to
1384 * vTaskSuspendAll().
1386 * xTaskResumeAll() only resumes the scheduler. It does not unsuspend tasks
1387 * that were previously suspended by a call to vTaskSuspend().
1389 * @return If resuming the scheduler caused a context switch then pdTRUE is
1390 * returned, otherwise pdFALSE is returned.
1394 * void vTask1( void * pvParameters )
1398 * // Task code goes here.
1402 * // At some point the task wants to perform a long operation during
1403 * // which it does not want to get swapped out. It cannot use
1404 * // taskENTER_CRITICAL ()/taskEXIT_CRITICAL () as the length of the
1405 * // operation may cause interrupts to be missed - including the
1408 * // Prevent the real time kernel swapping out the task.
1409 * vTaskSuspendAll ();
1411 * // Perform the operation here. There is no need to use critical
1412 * // sections as we have all the microcontroller processing time.
1413 * // During this time interrupts will still operate and the real
1414 * // time kernel tick count will be maintained.
1418 * // The operation is complete. Restart the kernel. We want to force
1419 * // a context switch - but there is no point if resuming the scheduler
1420 * // caused a context switch already.
1421 * if( !xTaskResumeAll () )
1428 * \defgroup xTaskResumeAll xTaskResumeAll
1429 * \ingroup SchedulerControl
1431 BaseType_t xTaskResumeAll( void ) PRIVILEGED_FUNCTION;
1433 /*-----------------------------------------------------------
1435 *----------------------------------------------------------*/
1440 * TickType_t xTaskGetTickCount( void );
1443 * @return The count of ticks since vTaskStartScheduler was called.
1445 * \defgroup xTaskGetTickCount xTaskGetTickCount
1446 * \ingroup TaskUtils
1448 TickType_t xTaskGetTickCount( void ) PRIVILEGED_FUNCTION;
1453 * TickType_t xTaskGetTickCountFromISR( void );
1456 * @return The count of ticks since vTaskStartScheduler was called.
1458 * This is a version of xTaskGetTickCount() that is safe to be called from an
1459 * ISR - provided that TickType_t is the natural word size of the
1460 * microcontroller being used or interrupt nesting is either not supported or
1463 * \defgroup xTaskGetTickCountFromISR xTaskGetTickCountFromISR
1464 * \ingroup TaskUtils
1466 TickType_t xTaskGetTickCountFromISR( void ) PRIVILEGED_FUNCTION;
1471 * uint16_t uxTaskGetNumberOfTasks( void );
1474 * @return The number of tasks that the real time kernel is currently managing.
1475 * This includes all ready, blocked and suspended tasks. A task that
1476 * has been deleted but not yet freed by the idle task will also be
1477 * included in the count.
1479 * \defgroup uxTaskGetNumberOfTasks uxTaskGetNumberOfTasks
1480 * \ingroup TaskUtils
1482 UBaseType_t uxTaskGetNumberOfTasks( void ) PRIVILEGED_FUNCTION;
1487 * char *pcTaskGetName( TaskHandle_t xTaskToQuery );
1490 * @return The text (human readable) name of the task referenced by the handle
1491 * xTaskToQuery. A task can query its own name by either passing in its own
1492 * handle, or by setting xTaskToQuery to NULL.
1494 * \defgroup pcTaskGetName pcTaskGetName
1495 * \ingroup TaskUtils
1497 char * pcTaskGetName( TaskHandle_t xTaskToQuery ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
1502 * TaskHandle_t xTaskGetHandle( const char *pcNameToQuery );
1505 * NOTE: This function takes a relatively long time to complete and should be
1508 * @return The handle of the task that has the human readable name pcNameToQuery.
1509 * NULL is returned if no matching name is found. INCLUDE_xTaskGetHandle
1510 * must be set to 1 in FreeRTOSConfig.h for pcTaskGetHandle() to be available.
1512 * \defgroup pcTaskGetHandle pcTaskGetHandle
1513 * \ingroup TaskUtils
1515 TaskHandle_t xTaskGetHandle( const char * pcNameToQuery ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
1520 * BaseType_t xTaskGetStaticBuffers( TaskHandle_t xTask,
1521 * StackType_t ** ppuxStackBuffer,
1522 * StaticTask_t ** ppxTaskBuffer );
1525 * Retrieve pointers to a statically created task's data structure
1526 * buffer and stack buffer. These are the same buffers that are supplied
1527 * at the time of creation.
1529 * @param xTask The task for which to retrieve the buffers.
1531 * @param ppuxStackBuffer Used to return a pointer to the task's stack buffer.
1533 * @param ppxTaskBuffer Used to return a pointer to the task's data structure
1536 * @return pdTRUE if buffers were retrieved, pdFALSE otherwise.
1538 * \defgroup xTaskGetStaticBuffers xTaskGetStaticBuffers
1539 * \ingroup TaskUtils
1541 #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
1542 BaseType_t xTaskGetStaticBuffers( TaskHandle_t xTask,
1543 StackType_t ** ppuxStackBuffer,
1544 StaticTask_t ** ppxTaskBuffer ) PRIVILEGED_FUNCTION;
1545 #endif /* configSUPPORT_STATIC_ALLOCATION */
1550 * UBaseType_t uxTaskGetStackHighWaterMark( TaskHandle_t xTask );
1553 * INCLUDE_uxTaskGetStackHighWaterMark must be set to 1 in FreeRTOSConfig.h for
1554 * this function to be available.
1556 * Returns the high water mark of the stack associated with xTask. That is,
1557 * the minimum free stack space there has been (in words, so on a 32 bit machine
1558 * a value of 1 means 4 bytes) since the task started. The smaller the returned
1559 * number the closer the task has come to overflowing its stack.
1561 * uxTaskGetStackHighWaterMark() and uxTaskGetStackHighWaterMark2() are the
1562 * same except for their return type. Using configSTACK_DEPTH_TYPE allows the
1563 * user to determine the return type. It gets around the problem of the value
1564 * overflowing on 8-bit types without breaking backward compatibility for
1565 * applications that expect an 8-bit return type.
1567 * @param xTask Handle of the task associated with the stack to be checked.
1568 * Set xTask to NULL to check the stack of the calling task.
1570 * @return The smallest amount of free stack space there has been (in words, so
1571 * actual spaces on the stack rather than bytes) since the task referenced by
1572 * xTask was created.
1574 UBaseType_t uxTaskGetStackHighWaterMark( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
1579 * configSTACK_DEPTH_TYPE uxTaskGetStackHighWaterMark2( TaskHandle_t xTask );
1582 * INCLUDE_uxTaskGetStackHighWaterMark2 must be set to 1 in FreeRTOSConfig.h for
1583 * this function to be available.
1585 * Returns the high water mark of the stack associated with xTask. That is,
1586 * the minimum free stack space there has been (in words, so on a 32 bit machine
1587 * a value of 1 means 4 bytes) since the task started. The smaller the returned
1588 * number the closer the task has come to overflowing its stack.
1590 * uxTaskGetStackHighWaterMark() and uxTaskGetStackHighWaterMark2() are the
1591 * same except for their return type. Using configSTACK_DEPTH_TYPE allows the
1592 * user to determine the return type. It gets around the problem of the value
1593 * overflowing on 8-bit types without breaking backward compatibility for
1594 * applications that expect an 8-bit return type.
1596 * @param xTask Handle of the task associated with the stack to be checked.
1597 * Set xTask to NULL to check the stack of the calling task.
1599 * @return The smallest amount of free stack space there has been (in words, so
1600 * actual spaces on the stack rather than bytes) since the task referenced by
1601 * xTask was created.
1603 configSTACK_DEPTH_TYPE uxTaskGetStackHighWaterMark2( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
1605 /* When using trace macros it is sometimes necessary to include task.h before
1606 * FreeRTOS.h. When this is done TaskHookFunction_t will not yet have been defined,
1607 * so the following two prototypes will cause a compilation error. This can be
1608 * fixed by simply guarding against the inclusion of these two prototypes unless
1609 * they are explicitly required by the configUSE_APPLICATION_TASK_TAG configuration
1611 #ifdef configUSE_APPLICATION_TASK_TAG
1612 #if configUSE_APPLICATION_TASK_TAG == 1
1617 * void vTaskSetApplicationTaskTag( TaskHandle_t xTask, TaskHookFunction_t pxHookFunction );
1620 * Sets pxHookFunction to be the task hook function used by the task xTask.
1621 * Passing xTask as NULL has the effect of setting the calling tasks hook
1624 void vTaskSetApplicationTaskTag( TaskHandle_t xTask,
1625 TaskHookFunction_t pxHookFunction ) PRIVILEGED_FUNCTION;
1630 * void xTaskGetApplicationTaskTag( TaskHandle_t xTask );
1633 * Returns the pxHookFunction value assigned to the task xTask. Do not
1634 * call from an interrupt service routine - call
1635 * xTaskGetApplicationTaskTagFromISR() instead.
1637 TaskHookFunction_t xTaskGetApplicationTaskTag( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
1642 * void xTaskGetApplicationTaskTagFromISR( TaskHandle_t xTask );
1645 * Returns the pxHookFunction value assigned to the task xTask. Can
1646 * be called from an interrupt service routine.
1648 TaskHookFunction_t xTaskGetApplicationTaskTagFromISR( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
1649 #endif /* configUSE_APPLICATION_TASK_TAG ==1 */
1650 #endif /* ifdef configUSE_APPLICATION_TASK_TAG */
1652 #if ( configNUM_THREAD_LOCAL_STORAGE_POINTERS > 0 )
1654 /* Each task contains an array of pointers that is dimensioned by the
1655 * configNUM_THREAD_LOCAL_STORAGE_POINTERS setting in FreeRTOSConfig.h. The
1656 * kernel does not use the pointers itself, so the application writer can use
1657 * the pointers for any purpose they wish. The following two functions are
1658 * used to set and query a pointer respectively. */
1659 void vTaskSetThreadLocalStoragePointer( TaskHandle_t xTaskToSet,
1661 void * pvValue ) PRIVILEGED_FUNCTION;
1662 void * pvTaskGetThreadLocalStoragePointer( TaskHandle_t xTaskToQuery,
1663 BaseType_t xIndex ) PRIVILEGED_FUNCTION;
1667 #if ( configCHECK_FOR_STACK_OVERFLOW > 0 )
1672 * void vApplicationStackOverflowHook( TaskHandle_t xTask, char *pcTaskName);
1675 * The application stack overflow hook is called when a stack overflow is detected for a task.
1677 * Details on stack overflow detection can be found here: https://www.FreeRTOS.org/Stacks-and-stack-overflow-checking.html
1679 * @param xTask the task that just exceeded its stack boundaries.
1680 * @param pcTaskName A character string containing the name of the offending task.
1682 void vApplicationStackOverflowHook( TaskHandle_t xTask,
1683 char * pcTaskName );
1687 #if ( configUSE_IDLE_HOOK == 1 )
1692 * void vApplicationIdleHook( void );
1695 * The application idle hook is called by the idle task.
1696 * This allows the application designer to add background functionality without
1697 * the overhead of a separate task.
1698 * NOTE: vApplicationIdleHook() MUST NOT, UNDER ANY CIRCUMSTANCES, CALL A FUNCTION THAT MIGHT BLOCK.
1700 void vApplicationIdleHook( void );
1705 #if ( configUSE_TICK_HOOK != 0 )
1710 * void vApplicationTickHook( void );
1713 * This hook function is called in the system tick handler after any OS work is completed.
1715 void vApplicationTickHook( void ); /*lint !e526 Symbol not defined as it is an application callback. */
1719 #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
1724 * void vApplicationGetIdleTaskMemory( StaticTask_t ** ppxIdleTaskTCBBuffer, StackType_t ** ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize )
1727 * This function is used to provide a statically allocated block of memory to FreeRTOS to hold the Idle Task TCB. This function is required when
1728 * configSUPPORT_STATIC_ALLOCATION is set. For more information see this URI: https://www.FreeRTOS.org/a00110.html#configSUPPORT_STATIC_ALLOCATION
1730 * @param ppxIdleTaskTCBBuffer A handle to a statically allocated TCB buffer
1731 * @param ppxIdleTaskStackBuffer A handle to a statically allocated Stack buffer for the idle task
1732 * @param pulIdleTaskStackSize A pointer to the number of elements that will fit in the allocated stack buffer
1734 void vApplicationGetIdleTaskMemory( StaticTask_t ** ppxIdleTaskTCBBuffer,
1735 StackType_t ** ppxIdleTaskStackBuffer,
1736 uint32_t * pulIdleTaskStackSize ); /*lint !e526 Symbol not defined as it is an application callback. */
1742 * BaseType_t xTaskCallApplicationTaskHook( TaskHandle_t xTask, void *pvParameter );
1745 * Calls the hook function associated with xTask. Passing xTask as NULL has
1746 * the effect of calling the Running tasks (the calling task) hook function.
1748 * pvParameter is passed to the hook function for the task to interpret as it
1749 * wants. The return value is the value returned by the task hook function
1750 * registered by the user.
1752 BaseType_t xTaskCallApplicationTaskHook( TaskHandle_t xTask,
1753 void * pvParameter ) PRIVILEGED_FUNCTION;
1756 * xTaskGetIdleTaskHandle() is only available if
1757 * INCLUDE_xTaskGetIdleTaskHandle is set to 1 in FreeRTOSConfig.h.
1759 * Simply returns the handle of the idle task. It is not valid to call
1760 * xTaskGetIdleTaskHandle() before the scheduler has been started.
1762 TaskHandle_t xTaskGetIdleTaskHandle( void ) PRIVILEGED_FUNCTION;
1765 * configUSE_TRACE_FACILITY must be defined as 1 in FreeRTOSConfig.h for
1766 * uxTaskGetSystemState() to be available.
1768 * uxTaskGetSystemState() populates an TaskStatus_t structure for each task in
1769 * the system. TaskStatus_t structures contain, among other things, members
1770 * for the task handle, task name, task priority, task state, and total amount
1771 * of run time consumed by the task. See the TaskStatus_t structure
1772 * definition in this file for the full member list.
1774 * NOTE: This function is intended for debugging use only as its use results in
1775 * the scheduler remaining suspended for an extended period.
1777 * @param pxTaskStatusArray A pointer to an array of TaskStatus_t structures.
1778 * The array must contain at least one TaskStatus_t structure for each task
1779 * that is under the control of the RTOS. The number of tasks under the control
1780 * of the RTOS can be determined using the uxTaskGetNumberOfTasks() API function.
1782 * @param uxArraySize The size of the array pointed to by the pxTaskStatusArray
1783 * parameter. The size is specified as the number of indexes in the array, or
1784 * the number of TaskStatus_t structures contained in the array, not by the
1785 * number of bytes in the array.
1787 * @param pulTotalRunTime If configGENERATE_RUN_TIME_STATS is set to 1 in
1788 * FreeRTOSConfig.h then *pulTotalRunTime is set by uxTaskGetSystemState() to the
1789 * total run time (as defined by the run time stats clock, see
1790 * https://www.FreeRTOS.org/rtos-run-time-stats.html) since the target booted.
1791 * pulTotalRunTime can be set to NULL to omit the total run time information.
1793 * @return The number of TaskStatus_t structures that were populated by
1794 * uxTaskGetSystemState(). This should equal the number returned by the
1795 * uxTaskGetNumberOfTasks() API function, but will be zero if the value passed
1796 * in the uxArraySize parameter was too small.
1800 * // This example demonstrates how a human readable table of run time stats
1801 * // information is generated from raw data provided by uxTaskGetSystemState().
1802 * // The human readable table is written to pcWriteBuffer
1803 * void vTaskGetRunTimeStats( char *pcWriteBuffer )
1805 * TaskStatus_t *pxTaskStatusArray;
1806 * volatile UBaseType_t uxArraySize, x;
1807 * configRUN_TIME_COUNTER_TYPE ulTotalRunTime, ulStatsAsPercentage;
1809 * // Make sure the write buffer does not contain a string.
1810 * pcWriteBuffer = 0x00;
1812 * // Take a snapshot of the number of tasks in case it changes while this
1813 * // function is executing.
1814 * uxArraySize = uxTaskGetNumberOfTasks();
1816 * // Allocate a TaskStatus_t structure for each task. An array could be
1817 * // allocated statically at compile time.
1818 * pxTaskStatusArray = pvPortMalloc( uxArraySize * sizeof( TaskStatus_t ) );
1820 * if( pxTaskStatusArray != NULL )
1822 * // Generate raw status information about each task.
1823 * uxArraySize = uxTaskGetSystemState( pxTaskStatusArray, uxArraySize, &ulTotalRunTime );
1825 * // For percentage calculations.
1826 * ulTotalRunTime /= 100UL;
1828 * // Avoid divide by zero errors.
1829 * if( ulTotalRunTime > 0 )
1831 * // For each populated position in the pxTaskStatusArray array,
1832 * // format the raw data as human readable ASCII data
1833 * for( x = 0; x < uxArraySize; x++ )
1835 * // What percentage of the total run time has the task used?
1836 * // This will always be rounded down to the nearest integer.
1837 * // ulTotalRunTimeDiv100 has already been divided by 100.
1838 * ulStatsAsPercentage = pxTaskStatusArray[ x ].ulRunTimeCounter / ulTotalRunTime;
1840 * if( ulStatsAsPercentage > 0UL )
1842 * sprintf( pcWriteBuffer, "%s\t\t%lu\t\t%lu%%\r\n", pxTaskStatusArray[ x ].pcTaskName, pxTaskStatusArray[ x ].ulRunTimeCounter, ulStatsAsPercentage );
1846 * // If the percentage is zero here then the task has
1847 * // consumed less than 1% of the total run time.
1848 * sprintf( pcWriteBuffer, "%s\t\t%lu\t\t<1%%\r\n", pxTaskStatusArray[ x ].pcTaskName, pxTaskStatusArray[ x ].ulRunTimeCounter );
1851 * pcWriteBuffer += strlen( ( char * ) pcWriteBuffer );
1855 * // The array is no longer needed, free the memory it consumes.
1856 * vPortFree( pxTaskStatusArray );
1861 UBaseType_t uxTaskGetSystemState( TaskStatus_t * const pxTaskStatusArray,
1862 const UBaseType_t uxArraySize,
1863 configRUN_TIME_COUNTER_TYPE * const pulTotalRunTime ) PRIVILEGED_FUNCTION;
1868 * void vTaskList( char *pcWriteBuffer );
1871 * configUSE_TRACE_FACILITY and configUSE_STATS_FORMATTING_FUNCTIONS must
1872 * both be defined as 1 for this function to be available. See the
1873 * configuration section of the FreeRTOS.org website for more information.
1875 * NOTE 1: This function will disable interrupts for its duration. It is
1876 * not intended for normal application runtime use but as a debug aid.
1878 * Lists all the current tasks, along with their current state and stack
1879 * usage high water mark.
1881 * Tasks are reported as blocked ('B'), ready ('R'), deleted ('D') or
1886 * This function is provided for convenience only, and is used by many of the
1887 * demo applications. Do not consider it to be part of the scheduler.
1889 * vTaskList() calls uxTaskGetSystemState(), then formats part of the
1890 * uxTaskGetSystemState() output into a human readable table that displays task:
1891 * names, states, priority, stack usage and task number.
1892 * Stack usage specified as the number of unused StackType_t words stack can hold
1893 * on top of stack - not the number of bytes.
1895 * vTaskList() has a dependency on the sprintf() C library function that might
1896 * bloat the code size, use a lot of stack, and provide different results on
1897 * different platforms. An alternative, tiny, third party, and limited
1898 * functionality implementation of sprintf() is provided in many of the
1899 * FreeRTOS/Demo sub-directories in a file called printf-stdarg.c (note
1900 * printf-stdarg.c does not provide a full snprintf() implementation!).
1902 * It is recommended that production systems call uxTaskGetSystemState()
1903 * directly to get access to raw stats data, rather than indirectly through a
1904 * call to vTaskList().
1906 * @param pcWriteBuffer A buffer into which the above mentioned details
1907 * will be written, in ASCII form. This buffer is assumed to be large
1908 * enough to contain the generated report. Approximately 40 bytes per
1909 * task should be sufficient.
1911 * \defgroup vTaskList vTaskList
1912 * \ingroup TaskUtils
1914 void vTaskList( char * pcWriteBuffer ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
1919 * void vTaskGetRunTimeStats( char *pcWriteBuffer );
1922 * configGENERATE_RUN_TIME_STATS and configUSE_STATS_FORMATTING_FUNCTIONS
1923 * must both be defined as 1 for this function to be available. The application
1924 * must also then provide definitions for
1925 * portCONFIGURE_TIMER_FOR_RUN_TIME_STATS() and portGET_RUN_TIME_COUNTER_VALUE()
1926 * to configure a peripheral timer/counter and return the timers current count
1927 * value respectively. The counter should be at least 10 times the frequency of
1930 * NOTE 1: This function will disable interrupts for its duration. It is
1931 * not intended for normal application runtime use but as a debug aid.
1933 * Setting configGENERATE_RUN_TIME_STATS to 1 will result in a total
1934 * accumulated execution time being stored for each task. The resolution
1935 * of the accumulated time value depends on the frequency of the timer
1936 * configured by the portCONFIGURE_TIMER_FOR_RUN_TIME_STATS() macro.
1937 * Calling vTaskGetRunTimeStats() writes the total execution time of each
1938 * task into a buffer, both as an absolute count value and as a percentage
1939 * of the total system execution time.
1943 * This function is provided for convenience only, and is used by many of the
1944 * demo applications. Do not consider it to be part of the scheduler.
1946 * vTaskGetRunTimeStats() calls uxTaskGetSystemState(), then formats part of the
1947 * uxTaskGetSystemState() output into a human readable table that displays the
1948 * amount of time each task has spent in the Running state in both absolute and
1951 * vTaskGetRunTimeStats() has a dependency on the sprintf() C library function
1952 * that might bloat the code size, use a lot of stack, and provide different
1953 * results on different platforms. An alternative, tiny, third party, and
1954 * limited functionality implementation of sprintf() is provided in many of the
1955 * FreeRTOS/Demo sub-directories in a file called printf-stdarg.c (note
1956 * printf-stdarg.c does not provide a full snprintf() implementation!).
1958 * It is recommended that production systems call uxTaskGetSystemState() directly
1959 * to get access to raw stats data, rather than indirectly through a call to
1960 * vTaskGetRunTimeStats().
1962 * @param pcWriteBuffer A buffer into which the execution times will be
1963 * written, in ASCII form. This buffer is assumed to be large enough to
1964 * contain the generated report. Approximately 40 bytes per task should
1967 * \defgroup vTaskGetRunTimeStats vTaskGetRunTimeStats
1968 * \ingroup TaskUtils
1970 void vTaskGetRunTimeStats( char * pcWriteBuffer ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
1975 * configRUN_TIME_COUNTER_TYPE ulTaskGetRunTimeCounter( const TaskHandle_t xTask );
1976 * configRUN_TIME_COUNTER_TYPE ulTaskGetRunTimePercent( const TaskHandle_t xTask );
1979 * configGENERATE_RUN_TIME_STATS must be defined as 1 for these functions to be
1980 * available. The application must also then provide definitions for
1981 * portCONFIGURE_TIMER_FOR_RUN_TIME_STATS() and
1982 * portGET_RUN_TIME_COUNTER_VALUE() to configure a peripheral timer/counter and
1983 * return the timers current count value respectively. The counter should be
1984 * at least 10 times the frequency of the tick count.
1986 * Setting configGENERATE_RUN_TIME_STATS to 1 will result in a total
1987 * accumulated execution time being stored for each task. The resolution
1988 * of the accumulated time value depends on the frequency of the timer
1989 * configured by the portCONFIGURE_TIMER_FOR_RUN_TIME_STATS() macro.
1990 * While uxTaskGetSystemState() and vTaskGetRunTimeStats() writes the total
1991 * execution time of each task into a buffer, ulTaskGetRunTimeCounter()
1992 * returns the total execution time of just one task and
1993 * ulTaskGetRunTimePercent() returns the percentage of the CPU time used by
1996 * @return The total run time of the given task or the percentage of the total
1997 * run time consumed by the given task. This is the amount of time the task
1998 * has actually been executing. The unit of time is dependent on the frequency
1999 * configured using the portCONFIGURE_TIMER_FOR_RUN_TIME_STATS() and
2000 * portGET_RUN_TIME_COUNTER_VALUE() macros.
2002 * \defgroup ulTaskGetRunTimeCounter ulTaskGetRunTimeCounter
2003 * \ingroup TaskUtils
2005 configRUN_TIME_COUNTER_TYPE ulTaskGetRunTimeCounter( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
2006 configRUN_TIME_COUNTER_TYPE ulTaskGetRunTimePercent( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
2011 * configRUN_TIME_COUNTER_TYPE ulTaskGetIdleRunTimeCounter( void );
2012 * configRUN_TIME_COUNTER_TYPE ulTaskGetIdleRunTimePercent( void );
2015 * configGENERATE_RUN_TIME_STATS must be defined as 1 for these functions to be
2016 * available. The application must also then provide definitions for
2017 * portCONFIGURE_TIMER_FOR_RUN_TIME_STATS() and
2018 * portGET_RUN_TIME_COUNTER_VALUE() to configure a peripheral timer/counter and
2019 * return the timers current count value respectively. The counter should be
2020 * at least 10 times the frequency of the tick count.
2022 * Setting configGENERATE_RUN_TIME_STATS to 1 will result in a total
2023 * accumulated execution time being stored for each task. The resolution
2024 * of the accumulated time value depends on the frequency of the timer
2025 * configured by the portCONFIGURE_TIMER_FOR_RUN_TIME_STATS() macro.
2026 * While uxTaskGetSystemState() and vTaskGetRunTimeStats() writes the total
2027 * execution time of each task into a buffer, ulTaskGetIdleRunTimeCounter()
2028 * returns the total execution time of just the idle task and
2029 * ulTaskGetIdleRunTimePercent() returns the percentage of the CPU time used by
2030 * just the idle task.
2032 * Note the amount of idle time is only a good measure of the slack time in a
2033 * system if there are no other tasks executing at the idle priority, tickless
2034 * idle is not used, and configIDLE_SHOULD_YIELD is set to 0.
2036 * @return The total run time of the idle task or the percentage of the total
2037 * run time consumed by the idle task. This is the amount of time the
2038 * idle task has actually been executing. The unit of time is dependent on the
2039 * frequency configured using the portCONFIGURE_TIMER_FOR_RUN_TIME_STATS() and
2040 * portGET_RUN_TIME_COUNTER_VALUE() macros.
2042 * \defgroup ulTaskGetIdleRunTimeCounter ulTaskGetIdleRunTimeCounter
2043 * \ingroup TaskUtils
2045 configRUN_TIME_COUNTER_TYPE ulTaskGetIdleRunTimeCounter( void ) PRIVILEGED_FUNCTION;
2046 configRUN_TIME_COUNTER_TYPE ulTaskGetIdleRunTimePercent( void ) PRIVILEGED_FUNCTION;
2051 * BaseType_t xTaskNotifyIndexed( TaskHandle_t xTaskToNotify, UBaseType_t uxIndexToNotify, uint32_t ulValue, eNotifyAction eAction );
2052 * BaseType_t xTaskNotify( TaskHandle_t xTaskToNotify, uint32_t ulValue, eNotifyAction eAction );
2055 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for details.
2057 * configUSE_TASK_NOTIFICATIONS must be undefined or defined as 1 for these
2058 * functions to be available.
2060 * Sends a direct to task notification to a task, with an optional value and
2063 * Each task has a private array of "notification values" (or 'notifications'),
2064 * each of which is a 32-bit unsigned integer (uint32_t). The constant
2065 * configTASK_NOTIFICATION_ARRAY_ENTRIES sets the number of indexes in the
2066 * array, and (for backward compatibility) defaults to 1 if left undefined.
2067 * Prior to FreeRTOS V10.4.0 there was only one notification value per task.
2069 * Events can be sent to a task using an intermediary object. Examples of such
2070 * objects are queues, semaphores, mutexes and event groups. Task notifications
2071 * are a method of sending an event directly to a task without the need for such
2072 * an intermediary object.
2074 * A notification sent to a task can optionally perform an action, such as
2075 * update, overwrite or increment one of the task's notification values. In
2076 * that way task notifications can be used to send data to a task, or be used as
2077 * light weight and fast binary or counting semaphores.
2079 * A task can use xTaskNotifyWaitIndexed() or ulTaskNotifyTakeIndexed() to
2080 * [optionally] block to wait for a notification to be pending. The task does
2081 * not consume any CPU time while it is in the Blocked state.
2083 * A notification sent to a task will remain pending until it is cleared by the
2084 * task calling xTaskNotifyWaitIndexed() or ulTaskNotifyTakeIndexed() (or their
2085 * un-indexed equivalents). If the task was already in the Blocked state to
2086 * wait for a notification when the notification arrives then the task will
2087 * automatically be removed from the Blocked state (unblocked) and the
2088 * notification cleared.
2090 * **NOTE** Each notification within the array operates independently - a task
2091 * can only block on one notification within the array at a time and will not be
2092 * unblocked by a notification sent to any other array index.
2094 * Backward compatibility information:
2095 * Prior to FreeRTOS V10.4.0 each task had a single "notification value", and
2096 * all task notification API functions operated on that value. Replacing the
2097 * single notification value with an array of notification values necessitated a
2098 * new set of API functions that could address specific notifications within the
2099 * array. xTaskNotify() is the original API function, and remains backward
2100 * compatible by always operating on the notification value at index 0 in the
2101 * array. Calling xTaskNotify() is equivalent to calling xTaskNotifyIndexed()
2102 * with the uxIndexToNotify parameter set to 0.
2104 * @param xTaskToNotify The handle of the task being notified. The handle to a
2105 * task can be returned from the xTaskCreate() API function used to create the
2106 * task, and the handle of the currently running task can be obtained by calling
2107 * xTaskGetCurrentTaskHandle().
2109 * @param uxIndexToNotify The index within the target task's array of
2110 * notification values to which the notification is to be sent. uxIndexToNotify
2111 * must be less than configTASK_NOTIFICATION_ARRAY_ENTRIES. xTaskNotify() does
2112 * not have this parameter and always sends notifications to index 0.
2114 * @param ulValue Data that can be sent with the notification. How the data is
2115 * used depends on the value of the eAction parameter.
2117 * @param eAction Specifies how the notification updates the task's notification
2118 * value, if at all. Valid values for eAction are as follows:
2121 * The target notification value is bitwise ORed with ulValue.
2122 * xTaskNotifyIndexed() always returns pdPASS in this case.
2125 * The target notification value is incremented. ulValue is not used and
2126 * xTaskNotifyIndexed() always returns pdPASS in this case.
2128 * eSetValueWithOverwrite -
2129 * The target notification value is set to the value of ulValue, even if the
2130 * task being notified had not yet processed the previous notification at the
2131 * same array index (the task already had a notification pending at that index).
2132 * xTaskNotifyIndexed() always returns pdPASS in this case.
2134 * eSetValueWithoutOverwrite -
2135 * If the task being notified did not already have a notification pending at the
2136 * same array index then the target notification value is set to ulValue and
2137 * xTaskNotifyIndexed() will return pdPASS. If the task being notified already
2138 * had a notification pending at the same array index then no action is
2139 * performed and pdFAIL is returned.
2142 * The task receives a notification at the specified array index without the
2143 * notification value at that index being updated. ulValue is not used and
2144 * xTaskNotifyIndexed() always returns pdPASS in this case.
2146 * pulPreviousNotificationValue -
2147 * Can be used to pass out the subject task's notification value before any
2148 * bits are modified by the notify function.
2150 * @return Dependent on the value of eAction. See the description of the
2151 * eAction parameter.
2153 * \defgroup xTaskNotifyIndexed xTaskNotifyIndexed
2154 * \ingroup TaskNotifications
2156 BaseType_t xTaskGenericNotify( TaskHandle_t xTaskToNotify,
2157 UBaseType_t uxIndexToNotify,
2159 eNotifyAction eAction,
2160 uint32_t * pulPreviousNotificationValue ) PRIVILEGED_FUNCTION;
2161 #define xTaskNotify( xTaskToNotify, ulValue, eAction ) \
2162 xTaskGenericNotify( ( xTaskToNotify ), ( tskDEFAULT_INDEX_TO_NOTIFY ), ( ulValue ), ( eAction ), NULL )
2163 #define xTaskNotifyIndexed( xTaskToNotify, uxIndexToNotify, ulValue, eAction ) \
2164 xTaskGenericNotify( ( xTaskToNotify ), ( uxIndexToNotify ), ( ulValue ), ( eAction ), NULL )
2169 * BaseType_t xTaskNotifyAndQueryIndexed( TaskHandle_t xTaskToNotify, UBaseType_t uxIndexToNotify, uint32_t ulValue, eNotifyAction eAction, uint32_t *pulPreviousNotifyValue );
2170 * BaseType_t xTaskNotifyAndQuery( TaskHandle_t xTaskToNotify, uint32_t ulValue, eNotifyAction eAction, uint32_t *pulPreviousNotifyValue );
2173 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for details.
2175 * xTaskNotifyAndQueryIndexed() performs the same operation as
2176 * xTaskNotifyIndexed() with the addition that it also returns the subject
2177 * task's prior notification value (the notification value at the time the
2178 * function is called rather than when the function returns) in the additional
2179 * pulPreviousNotifyValue parameter.
2181 * xTaskNotifyAndQuery() performs the same operation as xTaskNotify() with the
2182 * addition that it also returns the subject task's prior notification value
2183 * (the notification value as it was at the time the function is called, rather
2184 * than when the function returns) in the additional pulPreviousNotifyValue
2187 * \defgroup xTaskNotifyAndQueryIndexed xTaskNotifyAndQueryIndexed
2188 * \ingroup TaskNotifications
2190 #define xTaskNotifyAndQuery( xTaskToNotify, ulValue, eAction, pulPreviousNotifyValue ) \
2191 xTaskGenericNotify( ( xTaskToNotify ), ( tskDEFAULT_INDEX_TO_NOTIFY ), ( ulValue ), ( eAction ), ( pulPreviousNotifyValue ) )
2192 #define xTaskNotifyAndQueryIndexed( xTaskToNotify, uxIndexToNotify, ulValue, eAction, pulPreviousNotifyValue ) \
2193 xTaskGenericNotify( ( xTaskToNotify ), ( uxIndexToNotify ), ( ulValue ), ( eAction ), ( pulPreviousNotifyValue ) )
2198 * BaseType_t xTaskNotifyIndexedFromISR( TaskHandle_t xTaskToNotify, UBaseType_t uxIndexToNotify, uint32_t ulValue, eNotifyAction eAction, BaseType_t *pxHigherPriorityTaskWoken );
2199 * BaseType_t xTaskNotifyFromISR( TaskHandle_t xTaskToNotify, uint32_t ulValue, eNotifyAction eAction, BaseType_t *pxHigherPriorityTaskWoken );
2202 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for details.
2204 * configUSE_TASK_NOTIFICATIONS must be undefined or defined as 1 for these
2205 * functions to be available.
2207 * A version of xTaskNotifyIndexed() that can be used from an interrupt service
2210 * Each task has a private array of "notification values" (or 'notifications'),
2211 * each of which is a 32-bit unsigned integer (uint32_t). The constant
2212 * configTASK_NOTIFICATION_ARRAY_ENTRIES sets the number of indexes in the
2213 * array, and (for backward compatibility) defaults to 1 if left undefined.
2214 * Prior to FreeRTOS V10.4.0 there was only one notification value per task.
2216 * Events can be sent to a task using an intermediary object. Examples of such
2217 * objects are queues, semaphores, mutexes and event groups. Task notifications
2218 * are a method of sending an event directly to a task without the need for such
2219 * an intermediary object.
2221 * A notification sent to a task can optionally perform an action, such as
2222 * update, overwrite or increment one of the task's notification values. In
2223 * that way task notifications can be used to send data to a task, or be used as
2224 * light weight and fast binary or counting semaphores.
2226 * A task can use xTaskNotifyWaitIndexed() to [optionally] block to wait for a
2227 * notification to be pending, or ulTaskNotifyTakeIndexed() to [optionally] block
2228 * to wait for a notification value to have a non-zero value. The task does
2229 * not consume any CPU time while it is in the Blocked state.
2231 * A notification sent to a task will remain pending until it is cleared by the
2232 * task calling xTaskNotifyWaitIndexed() or ulTaskNotifyTakeIndexed() (or their
2233 * un-indexed equivalents). If the task was already in the Blocked state to
2234 * wait for a notification when the notification arrives then the task will
2235 * automatically be removed from the Blocked state (unblocked) and the
2236 * notification cleared.
2238 * **NOTE** Each notification within the array operates independently - a task
2239 * can only block on one notification within the array at a time and will not be
2240 * unblocked by a notification sent to any other array index.
2242 * Backward compatibility information:
2243 * Prior to FreeRTOS V10.4.0 each task had a single "notification value", and
2244 * all task notification API functions operated on that value. Replacing the
2245 * single notification value with an array of notification values necessitated a
2246 * new set of API functions that could address specific notifications within the
2247 * array. xTaskNotifyFromISR() is the original API function, and remains
2248 * backward compatible by always operating on the notification value at index 0
2249 * within the array. Calling xTaskNotifyFromISR() is equivalent to calling
2250 * xTaskNotifyIndexedFromISR() with the uxIndexToNotify parameter set to 0.
2252 * @param uxIndexToNotify The index within the target task's array of
2253 * notification values to which the notification is to be sent. uxIndexToNotify
2254 * must be less than configTASK_NOTIFICATION_ARRAY_ENTRIES. xTaskNotifyFromISR()
2255 * does not have this parameter and always sends notifications to index 0.
2257 * @param xTaskToNotify The handle of the task being notified. The handle to a
2258 * task can be returned from the xTaskCreate() API function used to create the
2259 * task, and the handle of the currently running task can be obtained by calling
2260 * xTaskGetCurrentTaskHandle().
2262 * @param ulValue Data that can be sent with the notification. How the data is
2263 * used depends on the value of the eAction parameter.
2265 * @param eAction Specifies how the notification updates the task's notification
2266 * value, if at all. Valid values for eAction are as follows:
2269 * The task's notification value is bitwise ORed with ulValue. xTaskNotify()
2270 * always returns pdPASS in this case.
2273 * The task's notification value is incremented. ulValue is not used and
2274 * xTaskNotify() always returns pdPASS in this case.
2276 * eSetValueWithOverwrite -
2277 * The task's notification value is set to the value of ulValue, even if the
2278 * task being notified had not yet processed the previous notification (the
2279 * task already had a notification pending). xTaskNotify() always returns
2280 * pdPASS in this case.
2282 * eSetValueWithoutOverwrite -
2283 * If the task being notified did not already have a notification pending then
2284 * the task's notification value is set to ulValue and xTaskNotify() will
2285 * return pdPASS. If the task being notified already had a notification
2286 * pending then no action is performed and pdFAIL is returned.
2289 * The task receives a notification without its notification value being
2290 * updated. ulValue is not used and xTaskNotify() always returns pdPASS in
2293 * @param pxHigherPriorityTaskWoken xTaskNotifyFromISR() will set
2294 * *pxHigherPriorityTaskWoken to pdTRUE if sending the notification caused the
2295 * task to which the notification was sent to leave the Blocked state, and the
2296 * unblocked task has a priority higher than the currently running task. If
2297 * xTaskNotifyFromISR() sets this value to pdTRUE then a context switch should
2298 * be requested before the interrupt is exited. How a context switch is
2299 * requested from an ISR is dependent on the port - see the documentation page
2300 * for the port in use.
2302 * @return Dependent on the value of eAction. See the description of the
2303 * eAction parameter.
2305 * \defgroup xTaskNotifyIndexedFromISR xTaskNotifyIndexedFromISR
2306 * \ingroup TaskNotifications
2308 BaseType_t xTaskGenericNotifyFromISR( TaskHandle_t xTaskToNotify,
2309 UBaseType_t uxIndexToNotify,
2311 eNotifyAction eAction,
2312 uint32_t * pulPreviousNotificationValue,
2313 BaseType_t * pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION;
2314 #define xTaskNotifyFromISR( xTaskToNotify, ulValue, eAction, pxHigherPriorityTaskWoken ) \
2315 xTaskGenericNotifyFromISR( ( xTaskToNotify ), ( tskDEFAULT_INDEX_TO_NOTIFY ), ( ulValue ), ( eAction ), NULL, ( pxHigherPriorityTaskWoken ) )
2316 #define xTaskNotifyIndexedFromISR( xTaskToNotify, uxIndexToNotify, ulValue, eAction, pxHigherPriorityTaskWoken ) \
2317 xTaskGenericNotifyFromISR( ( xTaskToNotify ), ( uxIndexToNotify ), ( ulValue ), ( eAction ), NULL, ( pxHigherPriorityTaskWoken ) )
2322 * BaseType_t xTaskNotifyAndQueryIndexedFromISR( TaskHandle_t xTaskToNotify, UBaseType_t uxIndexToNotify, uint32_t ulValue, eNotifyAction eAction, uint32_t *pulPreviousNotificationValue, BaseType_t *pxHigherPriorityTaskWoken );
2323 * BaseType_t xTaskNotifyAndQueryFromISR( TaskHandle_t xTaskToNotify, uint32_t ulValue, eNotifyAction eAction, uint32_t *pulPreviousNotificationValue, BaseType_t *pxHigherPriorityTaskWoken );
2326 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for details.
2328 * xTaskNotifyAndQueryIndexedFromISR() performs the same operation as
2329 * xTaskNotifyIndexedFromISR() with the addition that it also returns the
2330 * subject task's prior notification value (the notification value at the time
2331 * the function is called rather than at the time the function returns) in the
2332 * additional pulPreviousNotifyValue parameter.
2334 * xTaskNotifyAndQueryFromISR() performs the same operation as
2335 * xTaskNotifyFromISR() with the addition that it also returns the subject
2336 * task's prior notification value (the notification value at the time the
2337 * function is called rather than at the time the function returns) in the
2338 * additional pulPreviousNotifyValue parameter.
2340 * \defgroup xTaskNotifyAndQueryIndexedFromISR xTaskNotifyAndQueryIndexedFromISR
2341 * \ingroup TaskNotifications
2343 #define xTaskNotifyAndQueryIndexedFromISR( xTaskToNotify, uxIndexToNotify, ulValue, eAction, pulPreviousNotificationValue, pxHigherPriorityTaskWoken ) \
2344 xTaskGenericNotifyFromISR( ( xTaskToNotify ), ( uxIndexToNotify ), ( ulValue ), ( eAction ), ( pulPreviousNotificationValue ), ( pxHigherPriorityTaskWoken ) )
2345 #define xTaskNotifyAndQueryFromISR( xTaskToNotify, ulValue, eAction, pulPreviousNotificationValue, pxHigherPriorityTaskWoken ) \
2346 xTaskGenericNotifyFromISR( ( xTaskToNotify ), ( tskDEFAULT_INDEX_TO_NOTIFY ), ( ulValue ), ( eAction ), ( pulPreviousNotificationValue ), ( pxHigherPriorityTaskWoken ) )
2351 * BaseType_t xTaskNotifyWaitIndexed( UBaseType_t uxIndexToWaitOn, uint32_t ulBitsToClearOnEntry, uint32_t ulBitsToClearOnExit, uint32_t *pulNotificationValue, TickType_t xTicksToWait );
2353 * BaseType_t xTaskNotifyWait( uint32_t ulBitsToClearOnEntry, uint32_t ulBitsToClearOnExit, uint32_t *pulNotificationValue, TickType_t xTicksToWait );
2356 * Waits for a direct to task notification to be pending at a given index within
2357 * an array of direct to task notifications.
2359 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for details.
2361 * configUSE_TASK_NOTIFICATIONS must be undefined or defined as 1 for this
2362 * function to be available.
2364 * Each task has a private array of "notification values" (or 'notifications'),
2365 * each of which is a 32-bit unsigned integer (uint32_t). The constant
2366 * configTASK_NOTIFICATION_ARRAY_ENTRIES sets the number of indexes in the
2367 * array, and (for backward compatibility) defaults to 1 if left undefined.
2368 * Prior to FreeRTOS V10.4.0 there was only one notification value per task.
2370 * Events can be sent to a task using an intermediary object. Examples of such
2371 * objects are queues, semaphores, mutexes and event groups. Task notifications
2372 * are a method of sending an event directly to a task without the need for such
2373 * an intermediary object.
2375 * A notification sent to a task can optionally perform an action, such as
2376 * update, overwrite or increment one of the task's notification values. In
2377 * that way task notifications can be used to send data to a task, or be used as
2378 * light weight and fast binary or counting semaphores.
2380 * A notification sent to a task will remain pending until it is cleared by the
2381 * task calling xTaskNotifyWaitIndexed() or ulTaskNotifyTakeIndexed() (or their
2382 * un-indexed equivalents). If the task was already in the Blocked state to
2383 * wait for a notification when the notification arrives then the task will
2384 * automatically be removed from the Blocked state (unblocked) and the
2385 * notification cleared.
2387 * A task can use xTaskNotifyWaitIndexed() to [optionally] block to wait for a
2388 * notification to be pending, or ulTaskNotifyTakeIndexed() to [optionally] block
2389 * to wait for a notification value to have a non-zero value. The task does
2390 * not consume any CPU time while it is in the Blocked state.
2392 * **NOTE** Each notification within the array operates independently - a task
2393 * can only block on one notification within the array at a time and will not be
2394 * unblocked by a notification sent to any other array index.
2396 * Backward compatibility information:
2397 * Prior to FreeRTOS V10.4.0 each task had a single "notification value", and
2398 * all task notification API functions operated on that value. Replacing the
2399 * single notification value with an array of notification values necessitated a
2400 * new set of API functions that could address specific notifications within the
2401 * array. xTaskNotifyWait() is the original API function, and remains backward
2402 * compatible by always operating on the notification value at index 0 in the
2403 * array. Calling xTaskNotifyWait() is equivalent to calling
2404 * xTaskNotifyWaitIndexed() with the uxIndexToWaitOn parameter set to 0.
2406 * @param uxIndexToWaitOn The index within the calling task's array of
2407 * notification values on which the calling task will wait for a notification to
2408 * be received. uxIndexToWaitOn must be less than
2409 * configTASK_NOTIFICATION_ARRAY_ENTRIES. xTaskNotifyWait() does
2410 * not have this parameter and always waits for notifications on index 0.
2412 * @param ulBitsToClearOnEntry Bits that are set in ulBitsToClearOnEntry value
2413 * will be cleared in the calling task's notification value before the task
2414 * checks to see if any notifications are pending, and optionally blocks if no
2415 * notifications are pending. Setting ulBitsToClearOnEntry to ULONG_MAX (if
2416 * limits.h is included) or 0xffffffffUL (if limits.h is not included) will have
2417 * the effect of resetting the task's notification value to 0. Setting
2418 * ulBitsToClearOnEntry to 0 will leave the task's notification value unchanged.
2420 * @param ulBitsToClearOnExit If a notification is pending or received before
2421 * the calling task exits the xTaskNotifyWait() function then the task's
2422 * notification value (see the xTaskNotify() API function) is passed out using
2423 * the pulNotificationValue parameter. Then any bits that are set in
2424 * ulBitsToClearOnExit will be cleared in the task's notification value (note
2425 * *pulNotificationValue is set before any bits are cleared). Setting
2426 * ulBitsToClearOnExit to ULONG_MAX (if limits.h is included) or 0xffffffffUL
2427 * (if limits.h is not included) will have the effect of resetting the task's
2428 * notification value to 0 before the function exits. Setting
2429 * ulBitsToClearOnExit to 0 will leave the task's notification value unchanged
2430 * when the function exits (in which case the value passed out in
2431 * pulNotificationValue will match the task's notification value).
2433 * @param pulNotificationValue Used to pass the task's notification value out
2434 * of the function. Note the value passed out will not be effected by the
2435 * clearing of any bits caused by ulBitsToClearOnExit being non-zero.
2437 * @param xTicksToWait The maximum amount of time that the task should wait in
2438 * the Blocked state for a notification to be received, should a notification
2439 * not already be pending when xTaskNotifyWait() was called. The task
2440 * will not consume any processing time while it is in the Blocked state. This
2441 * is specified in kernel ticks, the macro pdMS_TO_TICKS( value_in_ms ) can be
2442 * used to convert a time specified in milliseconds to a time specified in
2445 * @return If a notification was received (including notifications that were
2446 * already pending when xTaskNotifyWait was called) then pdPASS is
2447 * returned. Otherwise pdFAIL is returned.
2449 * \defgroup xTaskNotifyWaitIndexed xTaskNotifyWaitIndexed
2450 * \ingroup TaskNotifications
2452 BaseType_t xTaskGenericNotifyWait( UBaseType_t uxIndexToWaitOn,
2453 uint32_t ulBitsToClearOnEntry,
2454 uint32_t ulBitsToClearOnExit,
2455 uint32_t * pulNotificationValue,
2456 TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
2457 #define xTaskNotifyWait( ulBitsToClearOnEntry, ulBitsToClearOnExit, pulNotificationValue, xTicksToWait ) \
2458 xTaskGenericNotifyWait( tskDEFAULT_INDEX_TO_NOTIFY, ( ulBitsToClearOnEntry ), ( ulBitsToClearOnExit ), ( pulNotificationValue ), ( xTicksToWait ) )
2459 #define xTaskNotifyWaitIndexed( uxIndexToWaitOn, ulBitsToClearOnEntry, ulBitsToClearOnExit, pulNotificationValue, xTicksToWait ) \
2460 xTaskGenericNotifyWait( ( uxIndexToWaitOn ), ( ulBitsToClearOnEntry ), ( ulBitsToClearOnExit ), ( pulNotificationValue ), ( xTicksToWait ) )
2465 * BaseType_t xTaskNotifyGiveIndexed( TaskHandle_t xTaskToNotify, UBaseType_t uxIndexToNotify );
2466 * BaseType_t xTaskNotifyGive( TaskHandle_t xTaskToNotify );
2469 * Sends a direct to task notification to a particular index in the target
2470 * task's notification array in a manner similar to giving a counting semaphore.
2472 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for more details.
2474 * configUSE_TASK_NOTIFICATIONS must be undefined or defined as 1 for these
2475 * macros to be available.
2477 * Each task has a private array of "notification values" (or 'notifications'),
2478 * each of which is a 32-bit unsigned integer (uint32_t). The constant
2479 * configTASK_NOTIFICATION_ARRAY_ENTRIES sets the number of indexes in the
2480 * array, and (for backward compatibility) defaults to 1 if left undefined.
2481 * Prior to FreeRTOS V10.4.0 there was only one notification value per task.
2483 * Events can be sent to a task using an intermediary object. Examples of such
2484 * objects are queues, semaphores, mutexes and event groups. Task notifications
2485 * are a method of sending an event directly to a task without the need for such
2486 * an intermediary object.
2488 * A notification sent to a task can optionally perform an action, such as
2489 * update, overwrite or increment one of the task's notification values. In
2490 * that way task notifications can be used to send data to a task, or be used as
2491 * light weight and fast binary or counting semaphores.
2493 * xTaskNotifyGiveIndexed() is a helper macro intended for use when task
2494 * notifications are used as light weight and faster binary or counting
2495 * semaphore equivalents. Actual FreeRTOS semaphores are given using the
2496 * xSemaphoreGive() API function, the equivalent action that instead uses a task
2497 * notification is xTaskNotifyGiveIndexed().
2499 * When task notifications are being used as a binary or counting semaphore
2500 * equivalent then the task being notified should wait for the notification
2501 * using the ulTaskNotifyTakeIndexed() API function rather than the
2502 * xTaskNotifyWaitIndexed() API function.
2504 * **NOTE** Each notification within the array operates independently - a task
2505 * can only block on one notification within the array at a time and will not be
2506 * unblocked by a notification sent to any other array index.
2508 * Backward compatibility information:
2509 * Prior to FreeRTOS V10.4.0 each task had a single "notification value", and
2510 * all task notification API functions operated on that value. Replacing the
2511 * single notification value with an array of notification values necessitated a
2512 * new set of API functions that could address specific notifications within the
2513 * array. xTaskNotifyGive() is the original API function, and remains backward
2514 * compatible by always operating on the notification value at index 0 in the
2515 * array. Calling xTaskNotifyGive() is equivalent to calling
2516 * xTaskNotifyGiveIndexed() with the uxIndexToNotify parameter set to 0.
2518 * @param xTaskToNotify The handle of the task being notified. The handle to a
2519 * task can be returned from the xTaskCreate() API function used to create the
2520 * task, and the handle of the currently running task can be obtained by calling
2521 * xTaskGetCurrentTaskHandle().
2523 * @param uxIndexToNotify The index within the target task's array of
2524 * notification values to which the notification is to be sent. uxIndexToNotify
2525 * must be less than configTASK_NOTIFICATION_ARRAY_ENTRIES. xTaskNotifyGive()
2526 * does not have this parameter and always sends notifications to index 0.
2528 * @return xTaskNotifyGive() is a macro that calls xTaskNotify() with the
2529 * eAction parameter set to eIncrement - so pdPASS is always returned.
2531 * \defgroup xTaskNotifyGiveIndexed xTaskNotifyGiveIndexed
2532 * \ingroup TaskNotifications
2534 #define xTaskNotifyGive( xTaskToNotify ) \
2535 xTaskGenericNotify( ( xTaskToNotify ), ( tskDEFAULT_INDEX_TO_NOTIFY ), ( 0 ), eIncrement, NULL )
2536 #define xTaskNotifyGiveIndexed( xTaskToNotify, uxIndexToNotify ) \
2537 xTaskGenericNotify( ( xTaskToNotify ), ( uxIndexToNotify ), ( 0 ), eIncrement, NULL )
2542 * void vTaskNotifyGiveIndexedFromISR( TaskHandle_t xTaskHandle, UBaseType_t uxIndexToNotify, BaseType_t *pxHigherPriorityTaskWoken );
2543 * void vTaskNotifyGiveFromISR( TaskHandle_t xTaskHandle, BaseType_t *pxHigherPriorityTaskWoken );
2546 * A version of xTaskNotifyGiveIndexed() that can be called from an interrupt
2547 * service routine (ISR).
2549 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for more details.
2551 * configUSE_TASK_NOTIFICATIONS must be undefined or defined as 1 for this macro
2554 * Each task has a private array of "notification values" (or 'notifications'),
2555 * each of which is a 32-bit unsigned integer (uint32_t). The constant
2556 * configTASK_NOTIFICATION_ARRAY_ENTRIES sets the number of indexes in the
2557 * array, and (for backward compatibility) defaults to 1 if left undefined.
2558 * Prior to FreeRTOS V10.4.0 there was only one notification value per task.
2560 * Events can be sent to a task using an intermediary object. Examples of such
2561 * objects are queues, semaphores, mutexes and event groups. Task notifications
2562 * are a method of sending an event directly to a task without the need for such
2563 * an intermediary object.
2565 * A notification sent to a task can optionally perform an action, such as
2566 * update, overwrite or increment one of the task's notification values. In
2567 * that way task notifications can be used to send data to a task, or be used as
2568 * light weight and fast binary or counting semaphores.
2570 * vTaskNotifyGiveIndexedFromISR() is intended for use when task notifications
2571 * are used as light weight and faster binary or counting semaphore equivalents.
2572 * Actual FreeRTOS semaphores are given from an ISR using the
2573 * xSemaphoreGiveFromISR() API function, the equivalent action that instead uses
2574 * a task notification is vTaskNotifyGiveIndexedFromISR().
2576 * When task notifications are being used as a binary or counting semaphore
2577 * equivalent then the task being notified should wait for the notification
2578 * using the ulTaskNotifyTakeIndexed() API function rather than the
2579 * xTaskNotifyWaitIndexed() API function.
2581 * **NOTE** Each notification within the array operates independently - a task
2582 * can only block on one notification within the array at a time and will not be
2583 * unblocked by a notification sent to any other array index.
2585 * Backward compatibility information:
2586 * Prior to FreeRTOS V10.4.0 each task had a single "notification value", and
2587 * all task notification API functions operated on that value. Replacing the
2588 * single notification value with an array of notification values necessitated a
2589 * new set of API functions that could address specific notifications within the
2590 * array. xTaskNotifyFromISR() is the original API function, and remains
2591 * backward compatible by always operating on the notification value at index 0
2592 * within the array. Calling xTaskNotifyGiveFromISR() is equivalent to calling
2593 * xTaskNotifyGiveIndexedFromISR() with the uxIndexToNotify parameter set to 0.
2595 * @param xTaskToNotify The handle of the task being notified. The handle to a
2596 * task can be returned from the xTaskCreate() API function used to create the
2597 * task, and the handle of the currently running task can be obtained by calling
2598 * xTaskGetCurrentTaskHandle().
2600 * @param uxIndexToNotify The index within the target task's array of
2601 * notification values to which the notification is to be sent. uxIndexToNotify
2602 * must be less than configTASK_NOTIFICATION_ARRAY_ENTRIES.
2603 * xTaskNotifyGiveFromISR() does not have this parameter and always sends
2604 * notifications to index 0.
2606 * @param pxHigherPriorityTaskWoken vTaskNotifyGiveFromISR() will set
2607 * *pxHigherPriorityTaskWoken to pdTRUE if sending the notification caused the
2608 * task to which the notification was sent to leave the Blocked state, and the
2609 * unblocked task has a priority higher than the currently running task. If
2610 * vTaskNotifyGiveFromISR() sets this value to pdTRUE then a context switch
2611 * should be requested before the interrupt is exited. How a context switch is
2612 * requested from an ISR is dependent on the port - see the documentation page
2613 * for the port in use.
2615 * \defgroup vTaskNotifyGiveIndexedFromISR vTaskNotifyGiveIndexedFromISR
2616 * \ingroup TaskNotifications
2618 void vTaskGenericNotifyGiveFromISR( TaskHandle_t xTaskToNotify,
2619 UBaseType_t uxIndexToNotify,
2620 BaseType_t * pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION;
2621 #define vTaskNotifyGiveFromISR( xTaskToNotify, pxHigherPriorityTaskWoken ) \
2622 vTaskGenericNotifyGiveFromISR( ( xTaskToNotify ), ( tskDEFAULT_INDEX_TO_NOTIFY ), ( pxHigherPriorityTaskWoken ) )
2623 #define vTaskNotifyGiveIndexedFromISR( xTaskToNotify, uxIndexToNotify, pxHigherPriorityTaskWoken ) \
2624 vTaskGenericNotifyGiveFromISR( ( xTaskToNotify ), ( uxIndexToNotify ), ( pxHigherPriorityTaskWoken ) )
2629 * uint32_t ulTaskNotifyTakeIndexed( UBaseType_t uxIndexToWaitOn, BaseType_t xClearCountOnExit, TickType_t xTicksToWait );
2631 * uint32_t ulTaskNotifyTake( BaseType_t xClearCountOnExit, TickType_t xTicksToWait );
2634 * Waits for a direct to task notification on a particular index in the calling
2635 * task's notification array in a manner similar to taking a counting semaphore.
2637 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for details.
2639 * configUSE_TASK_NOTIFICATIONS must be undefined or defined as 1 for this
2640 * function to be available.
2642 * Each task has a private array of "notification values" (or 'notifications'),
2643 * each of which is a 32-bit unsigned integer (uint32_t). The constant
2644 * configTASK_NOTIFICATION_ARRAY_ENTRIES sets the number of indexes in the
2645 * array, and (for backward compatibility) defaults to 1 if left undefined.
2646 * Prior to FreeRTOS V10.4.0 there was only one notification value per task.
2648 * Events can be sent to a task using an intermediary object. Examples of such
2649 * objects are queues, semaphores, mutexes and event groups. Task notifications
2650 * are a method of sending an event directly to a task without the need for such
2651 * an intermediary object.
2653 * A notification sent to a task can optionally perform an action, such as
2654 * update, overwrite or increment one of the task's notification values. In
2655 * that way task notifications can be used to send data to a task, or be used as
2656 * light weight and fast binary or counting semaphores.
2658 * ulTaskNotifyTakeIndexed() is intended for use when a task notification is
2659 * used as a faster and lighter weight binary or counting semaphore alternative.
2660 * Actual FreeRTOS semaphores are taken using the xSemaphoreTake() API function,
2661 * the equivalent action that instead uses a task notification is
2662 * ulTaskNotifyTakeIndexed().
2664 * When a task is using its notification value as a binary or counting semaphore
2665 * other tasks should send notifications to it using the xTaskNotifyGiveIndexed()
2666 * macro, or xTaskNotifyIndex() function with the eAction parameter set to
2669 * ulTaskNotifyTakeIndexed() can either clear the task's notification value at
2670 * the array index specified by the uxIndexToWaitOn parameter to zero on exit,
2671 * in which case the notification value acts like a binary semaphore, or
2672 * decrement the notification value on exit, in which case the notification
2673 * value acts like a counting semaphore.
2675 * A task can use ulTaskNotifyTakeIndexed() to [optionally] block to wait for
2676 * a notification. The task does not consume any CPU time while it is in the
2679 * Where as xTaskNotifyWaitIndexed() will return when a notification is pending,
2680 * ulTaskNotifyTakeIndexed() will return when the task's notification value is
2683 * **NOTE** Each notification within the array operates independently - a task
2684 * can only block on one notification within the array at a time and will not be
2685 * unblocked by a notification sent to any other array index.
2687 * Backward compatibility information:
2688 * Prior to FreeRTOS V10.4.0 each task had a single "notification value", and
2689 * all task notification API functions operated on that value. Replacing the
2690 * single notification value with an array of notification values necessitated a
2691 * new set of API functions that could address specific notifications within the
2692 * array. ulTaskNotifyTake() is the original API function, and remains backward
2693 * compatible by always operating on the notification value at index 0 in the
2694 * array. Calling ulTaskNotifyTake() is equivalent to calling
2695 * ulTaskNotifyTakeIndexed() with the uxIndexToWaitOn parameter set to 0.
2697 * @param uxIndexToWaitOn The index within the calling task's array of
2698 * notification values on which the calling task will wait for a notification to
2699 * be non-zero. uxIndexToWaitOn must be less than
2700 * configTASK_NOTIFICATION_ARRAY_ENTRIES. xTaskNotifyTake() does
2701 * not have this parameter and always waits for notifications on index 0.
2703 * @param xClearCountOnExit if xClearCountOnExit is pdFALSE then the task's
2704 * notification value is decremented when the function exits. In this way the
2705 * notification value acts like a counting semaphore. If xClearCountOnExit is
2706 * not pdFALSE then the task's notification value is cleared to zero when the
2707 * function exits. In this way the notification value acts like a binary
2710 * @param xTicksToWait The maximum amount of time that the task should wait in
2711 * the Blocked state for the task's notification value to be greater than zero,
2712 * should the count not already be greater than zero when
2713 * ulTaskNotifyTake() was called. The task will not consume any processing
2714 * time while it is in the Blocked state. This is specified in kernel ticks,
2715 * the macro pdMS_TO_TICKS( value_in_ms ) can be used to convert a time
2716 * specified in milliseconds to a time specified in ticks.
2718 * @return The task's notification count before it is either cleared to zero or
2719 * decremented (see the xClearCountOnExit parameter).
2721 * \defgroup ulTaskNotifyTakeIndexed ulTaskNotifyTakeIndexed
2722 * \ingroup TaskNotifications
2724 uint32_t ulTaskGenericNotifyTake( UBaseType_t uxIndexToWaitOn,
2725 BaseType_t xClearCountOnExit,
2726 TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
2727 #define ulTaskNotifyTake( xClearCountOnExit, xTicksToWait ) \
2728 ulTaskGenericNotifyTake( ( tskDEFAULT_INDEX_TO_NOTIFY ), ( xClearCountOnExit ), ( xTicksToWait ) )
2729 #define ulTaskNotifyTakeIndexed( uxIndexToWaitOn, xClearCountOnExit, xTicksToWait ) \
2730 ulTaskGenericNotifyTake( ( uxIndexToWaitOn ), ( xClearCountOnExit ), ( xTicksToWait ) )
2735 * BaseType_t xTaskNotifyStateClearIndexed( TaskHandle_t xTask, UBaseType_t uxIndexToCLear );
2737 * BaseType_t xTaskNotifyStateClear( TaskHandle_t xTask );
2740 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for details.
2742 * configUSE_TASK_NOTIFICATIONS must be undefined or defined as 1 for these
2743 * functions to be available.
2745 * Each task has a private array of "notification values" (or 'notifications'),
2746 * each of which is a 32-bit unsigned integer (uint32_t). The constant
2747 * configTASK_NOTIFICATION_ARRAY_ENTRIES sets the number of indexes in the
2748 * array, and (for backward compatibility) defaults to 1 if left undefined.
2749 * Prior to FreeRTOS V10.4.0 there was only one notification value per task.
2751 * If a notification is sent to an index within the array of notifications then
2752 * the notification at that index is said to be 'pending' until it is read or
2753 * explicitly cleared by the receiving task. xTaskNotifyStateClearIndexed()
2754 * is the function that clears a pending notification without reading the
2755 * notification value. The notification value at the same array index is not
2756 * altered. Set xTask to NULL to clear the notification state of the calling
2759 * Backward compatibility information:
2760 * Prior to FreeRTOS V10.4.0 each task had a single "notification value", and
2761 * all task notification API functions operated on that value. Replacing the
2762 * single notification value with an array of notification values necessitated a
2763 * new set of API functions that could address specific notifications within the
2764 * array. xTaskNotifyStateClear() is the original API function, and remains
2765 * backward compatible by always operating on the notification value at index 0
2766 * within the array. Calling xTaskNotifyStateClear() is equivalent to calling
2767 * xTaskNotifyStateClearIndexed() with the uxIndexToNotify parameter set to 0.
2769 * @param xTask The handle of the RTOS task that will have a notification state
2770 * cleared. Set xTask to NULL to clear a notification state in the calling
2771 * task. To obtain a task's handle create the task using xTaskCreate() and
2772 * make use of the pxCreatedTask parameter, or create the task using
2773 * xTaskCreateStatic() and store the returned value, or use the task's name in
2774 * a call to xTaskGetHandle().
2776 * @param uxIndexToClear The index within the target task's array of
2777 * notification values to act upon. For example, setting uxIndexToClear to 1
2778 * will clear the state of the notification at index 1 within the array.
2779 * uxIndexToClear must be less than configTASK_NOTIFICATION_ARRAY_ENTRIES.
2780 * ulTaskNotifyStateClear() does not have this parameter and always acts on the
2781 * notification at index 0.
2783 * @return pdTRUE if the task's notification state was set to
2784 * eNotWaitingNotification, otherwise pdFALSE.
2786 * \defgroup xTaskNotifyStateClearIndexed xTaskNotifyStateClearIndexed
2787 * \ingroup TaskNotifications
2789 BaseType_t xTaskGenericNotifyStateClear( TaskHandle_t xTask,
2790 UBaseType_t uxIndexToClear ) PRIVILEGED_FUNCTION;
2791 #define xTaskNotifyStateClear( xTask ) \
2792 xTaskGenericNotifyStateClear( ( xTask ), ( tskDEFAULT_INDEX_TO_NOTIFY ) )
2793 #define xTaskNotifyStateClearIndexed( xTask, uxIndexToClear ) \
2794 xTaskGenericNotifyStateClear( ( xTask ), ( uxIndexToClear ) )
2799 * uint32_t ulTaskNotifyValueClearIndexed( TaskHandle_t xTask, UBaseType_t uxIndexToClear, uint32_t ulBitsToClear );
2801 * uint32_t ulTaskNotifyValueClear( TaskHandle_t xTask, uint32_t ulBitsToClear );
2804 * See https://www.FreeRTOS.org/RTOS-task-notifications.html for details.
2806 * configUSE_TASK_NOTIFICATIONS must be undefined or defined as 1 for these
2807 * functions to be available.
2809 * Each task has a private array of "notification values" (or 'notifications'),
2810 * each of which is a 32-bit unsigned integer (uint32_t). The constant
2811 * configTASK_NOTIFICATION_ARRAY_ENTRIES sets the number of indexes in the
2812 * array, and (for backward compatibility) defaults to 1 if left undefined.
2813 * Prior to FreeRTOS V10.4.0 there was only one notification value per task.
2815 * ulTaskNotifyValueClearIndexed() clears the bits specified by the
2816 * ulBitsToClear bit mask in the notification value at array index uxIndexToClear
2817 * of the task referenced by xTask.
2819 * Backward compatibility information:
2820 * Prior to FreeRTOS V10.4.0 each task had a single "notification value", and
2821 * all task notification API functions operated on that value. Replacing the
2822 * single notification value with an array of notification values necessitated a
2823 * new set of API functions that could address specific notifications within the
2824 * array. ulTaskNotifyValueClear() is the original API function, and remains
2825 * backward compatible by always operating on the notification value at index 0
2826 * within the array. Calling ulTaskNotifyValueClear() is equivalent to calling
2827 * ulTaskNotifyValueClearIndexed() with the uxIndexToClear parameter set to 0.
2829 * @param xTask The handle of the RTOS task that will have bits in one of its
2830 * notification values cleared. Set xTask to NULL to clear bits in a
2831 * notification value of the calling task. To obtain a task's handle create the
2832 * task using xTaskCreate() and make use of the pxCreatedTask parameter, or
2833 * create the task using xTaskCreateStatic() and store the returned value, or
2834 * use the task's name in a call to xTaskGetHandle().
2836 * @param uxIndexToClear The index within the target task's array of
2837 * notification values in which to clear the bits. uxIndexToClear
2838 * must be less than configTASK_NOTIFICATION_ARRAY_ENTRIES.
2839 * ulTaskNotifyValueClear() does not have this parameter and always clears bits
2840 * in the notification value at index 0.
2842 * @param ulBitsToClear Bit mask of the bits to clear in the notification value of
2843 * xTask. Set a bit to 1 to clear the corresponding bits in the task's notification
2844 * value. Set ulBitsToClear to 0xffffffff (UINT_MAX on 32-bit architectures) to clear
2845 * the notification value to 0. Set ulBitsToClear to 0 to query the task's
2846 * notification value without clearing any bits.
2849 * @return The value of the target task's notification value before the bits
2850 * specified by ulBitsToClear were cleared.
2851 * \defgroup ulTaskNotifyValueClear ulTaskNotifyValueClear
2852 * \ingroup TaskNotifications
2854 uint32_t ulTaskGenericNotifyValueClear( TaskHandle_t xTask,
2855 UBaseType_t uxIndexToClear,
2856 uint32_t ulBitsToClear ) PRIVILEGED_FUNCTION;
2857 #define ulTaskNotifyValueClear( xTask, ulBitsToClear ) \
2858 ulTaskGenericNotifyValueClear( ( xTask ), ( tskDEFAULT_INDEX_TO_NOTIFY ), ( ulBitsToClear ) )
2859 #define ulTaskNotifyValueClearIndexed( xTask, uxIndexToClear, ulBitsToClear ) \
2860 ulTaskGenericNotifyValueClear( ( xTask ), ( uxIndexToClear ), ( ulBitsToClear ) )
2865 * void vTaskSetTimeOutState( TimeOut_t * const pxTimeOut );
2868 * Capture the current time for future use with xTaskCheckForTimeOut().
2870 * @param pxTimeOut Pointer to a timeout object into which the current time
2871 * is to be captured. The captured time includes the tick count and the number
2872 * of times the tick count has overflowed since the system first booted.
2873 * \defgroup vTaskSetTimeOutState vTaskSetTimeOutState
2876 void vTaskSetTimeOutState( TimeOut_t * const pxTimeOut ) PRIVILEGED_FUNCTION;
2881 * BaseType_t xTaskCheckForTimeOut( TimeOut_t * const pxTimeOut, TickType_t * const pxTicksToWait );
2884 * Determines if pxTicksToWait ticks has passed since a time was captured
2885 * using a call to vTaskSetTimeOutState(). The captured time includes the tick
2886 * count and the number of times the tick count has overflowed.
2888 * @param pxTimeOut The time status as captured previously using
2889 * vTaskSetTimeOutState. If the timeout has not yet occurred, it is updated
2890 * to reflect the current time status.
2891 * @param pxTicksToWait The number of ticks to check for timeout i.e. if
2892 * pxTicksToWait ticks have passed since pxTimeOut was last updated (either by
2893 * vTaskSetTimeOutState() or xTaskCheckForTimeOut()), the timeout has occurred.
2894 * If the timeout has not occurred, pxTicksToWait is updated to reflect the
2895 * number of remaining ticks.
2897 * @return If timeout has occurred, pdTRUE is returned. Otherwise pdFALSE is
2898 * returned and pxTicksToWait is updated to reflect the number of remaining
2901 * @see https://www.FreeRTOS.org/xTaskCheckForTimeOut.html
2905 * // Driver library function used to receive uxWantedBytes from an Rx buffer
2906 * // that is filled by a UART interrupt. If there are not enough bytes in the
2907 * // Rx buffer then the task enters the Blocked state until it is notified that
2908 * // more data has been placed into the buffer. If there is still not enough
2909 * // data then the task re-enters the Blocked state, and xTaskCheckForTimeOut()
2910 * // is used to re-calculate the Block time to ensure the total amount of time
2911 * // spent in the Blocked state does not exceed MAX_TIME_TO_WAIT. This
2912 * // continues until either the buffer contains at least uxWantedBytes bytes,
2913 * // or the total amount of time spent in the Blocked state reaches
2914 * // MAX_TIME_TO_WAIT - at which point the task reads however many bytes are
2915 * // available up to a maximum of uxWantedBytes.
2917 * size_t xUART_Receive( uint8_t *pucBuffer, size_t uxWantedBytes )
2919 * size_t uxReceived = 0;
2920 * TickType_t xTicksToWait = MAX_TIME_TO_WAIT;
2921 * TimeOut_t xTimeOut;
2923 * // Initialize xTimeOut. This records the time at which this function
2925 * vTaskSetTimeOutState( &xTimeOut );
2927 * // Loop until the buffer contains the wanted number of bytes, or a
2928 * // timeout occurs.
2929 * while( UART_bytes_in_rx_buffer( pxUARTInstance ) < uxWantedBytes )
2931 * // The buffer didn't contain enough data so this task is going to
2932 * // enter the Blocked state. Adjusting xTicksToWait to account for
2933 * // any time that has been spent in the Blocked state within this
2934 * // function so far to ensure the total amount of time spent in the
2935 * // Blocked state does not exceed MAX_TIME_TO_WAIT.
2936 * if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) != pdFALSE )
2938 * //Timed out before the wanted number of bytes were available,
2943 * // Wait for a maximum of xTicksToWait ticks to be notified that the
2944 * // receive interrupt has placed more data into the buffer.
2945 * ulTaskNotifyTake( pdTRUE, xTicksToWait );
2948 * // Attempt to read uxWantedBytes from the receive buffer into pucBuffer.
2949 * // The actual number of bytes read (which might be less than
2950 * // uxWantedBytes) is returned.
2951 * uxReceived = UART_read_from_receive_buffer( pxUARTInstance,
2955 * return uxReceived;
2958 * \defgroup xTaskCheckForTimeOut xTaskCheckForTimeOut
2961 BaseType_t xTaskCheckForTimeOut( TimeOut_t * const pxTimeOut,
2962 TickType_t * const pxTicksToWait ) PRIVILEGED_FUNCTION;
2967 * BaseType_t xTaskCatchUpTicks( TickType_t xTicksToCatchUp );
2970 * This function corrects the tick count value after the application code has held
2971 * interrupts disabled for an extended period resulting in tick interrupts having
2974 * This function is similar to vTaskStepTick(), however, unlike
2975 * vTaskStepTick(), xTaskCatchUpTicks() may move the tick count forward past a
2976 * time at which a task should be removed from the blocked state. That means
2977 * tasks may have to be removed from the blocked state as the tick count is
2980 * @param xTicksToCatchUp The number of tick interrupts that have been missed due to
2981 * interrupts being disabled. Its value is not computed automatically, so must be
2982 * computed by the application writer.
2984 * @return pdTRUE if moving the tick count forward resulted in a task leaving the
2985 * blocked state and a context switch being performed. Otherwise pdFALSE.
2987 * \defgroup xTaskCatchUpTicks xTaskCatchUpTicks
2990 BaseType_t xTaskCatchUpTicks( TickType_t xTicksToCatchUp ) PRIVILEGED_FUNCTION;
2993 /*-----------------------------------------------------------
2994 * SCHEDULER INTERNALS AVAILABLE FOR PORTING PURPOSES
2995 *----------------------------------------------------------*/
2998 * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE. IT IS ONLY
2999 * INTENDED FOR USE WHEN IMPLEMENTING A PORT OF THE SCHEDULER AND IS
3000 * AN INTERFACE WHICH IS FOR THE EXCLUSIVE USE OF THE SCHEDULER.
3002 * Called from the real time kernel tick (either preemptive or cooperative),
3003 * this increments the tick count and checks if any tasks that are blocked
3004 * for a finite period required removing from a blocked list and placing on
3005 * a ready list. If a non-zero value is returned then a context switch is
3006 * required because either:
3007 * + A task was removed from a blocked list because its timeout had expired,
3009 * + Time slicing is in use and there is a task of equal priority to the
3010 * currently running task.
3012 BaseType_t xTaskIncrementTick( void ) PRIVILEGED_FUNCTION;
3015 * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE. IT IS AN
3016 * INTERFACE WHICH IS FOR THE EXCLUSIVE USE OF THE SCHEDULER.
3018 * THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED.
3020 * Removes the calling task from the ready list and places it both
3021 * on the list of tasks waiting for a particular event, and the
3022 * list of delayed tasks. The task will be removed from both lists
3023 * and replaced on the ready list should either the event occur (and
3024 * there be no higher priority tasks waiting on the same event) or
3025 * the delay period expires.
3027 * The 'unordered' version replaces the event list item value with the
3028 * xItemValue value, and inserts the list item at the end of the list.
3030 * The 'ordered' version uses the existing event list item value (which is the
3031 * owning task's priority) to insert the list item into the event list in task
3034 * @param pxEventList The list containing tasks that are blocked waiting
3035 * for the event to occur.
3037 * @param xItemValue The item value to use for the event list item when the
3038 * event list is not ordered by task priority.
3040 * @param xTicksToWait The maximum amount of time that the task should wait
3041 * for the event to occur. This is specified in kernel ticks, the constant
3042 * portTICK_PERIOD_MS can be used to convert kernel ticks into a real time
3045 void vTaskPlaceOnEventList( List_t * const pxEventList,
3046 const TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
3047 void vTaskPlaceOnUnorderedEventList( List_t * pxEventList,
3048 const TickType_t xItemValue,
3049 const TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
3052 * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE. IT IS AN
3053 * INTERFACE WHICH IS FOR THE EXCLUSIVE USE OF THE SCHEDULER.
3055 * THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED.
3057 * This function performs nearly the same function as vTaskPlaceOnEventList().
3058 * The difference being that this function does not permit tasks to block
3059 * indefinitely, whereas vTaskPlaceOnEventList() does.
3062 void vTaskPlaceOnEventListRestricted( List_t * const pxEventList,
3063 TickType_t xTicksToWait,
3064 const BaseType_t xWaitIndefinitely ) PRIVILEGED_FUNCTION;
3067 * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE. IT IS AN
3068 * INTERFACE WHICH IS FOR THE EXCLUSIVE USE OF THE SCHEDULER.
3070 * THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED.
3072 * Removes a task from both the specified event list and the list of blocked
3073 * tasks, and places it on a ready queue.
3075 * xTaskRemoveFromEventList()/vTaskRemoveFromUnorderedEventList() will be called
3076 * if either an event occurs to unblock a task, or the block timeout period
3079 * xTaskRemoveFromEventList() is used when the event list is in task priority
3080 * order. It removes the list item from the head of the event list as that will
3081 * have the highest priority owning task of all the tasks on the event list.
3082 * vTaskRemoveFromUnorderedEventList() is used when the event list is not
3083 * ordered and the event list items hold something other than the owning tasks
3084 * priority. In this case the event list item value is updated to the value
3085 * passed in the xItemValue parameter.
3087 * @return pdTRUE if the task being removed has a higher priority than the task
3088 * making the call, otherwise pdFALSE.
3090 BaseType_t xTaskRemoveFromEventList( const List_t * const pxEventList ) PRIVILEGED_FUNCTION;
3091 void vTaskRemoveFromUnorderedEventList( ListItem_t * pxEventListItem,
3092 const TickType_t xItemValue ) PRIVILEGED_FUNCTION;
3095 * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE. IT IS ONLY
3096 * INTENDED FOR USE WHEN IMPLEMENTING A PORT OF THE SCHEDULER AND IS
3097 * AN INTERFACE WHICH IS FOR THE EXCLUSIVE USE OF THE SCHEDULER.
3099 * Sets the pointer to the current TCB to the TCB of the highest priority task
3100 * that is ready to run.
3102 portDONT_DISCARD void vTaskSwitchContext( void ) PRIVILEGED_FUNCTION;
3105 * THESE FUNCTIONS MUST NOT BE USED FROM APPLICATION CODE. THEY ARE USED BY
3106 * THE EVENT BITS MODULE.
3108 TickType_t uxTaskResetEventItemValue( void ) PRIVILEGED_FUNCTION;
3111 * Return the handle of the calling task.
3113 TaskHandle_t xTaskGetCurrentTaskHandle( void ) PRIVILEGED_FUNCTION;
3116 * Shortcut used by the queue implementation to prevent unnecessary call to
3119 void vTaskMissedYield( void ) PRIVILEGED_FUNCTION;
3122 * Returns the scheduler state as taskSCHEDULER_RUNNING,
3123 * taskSCHEDULER_NOT_STARTED or taskSCHEDULER_SUSPENDED.
3125 BaseType_t xTaskGetSchedulerState( void ) PRIVILEGED_FUNCTION;
3128 * Raises the priority of the mutex holder to that of the calling task should
3129 * the mutex holder have a priority less than the calling task.
3131 BaseType_t xTaskPriorityInherit( TaskHandle_t const pxMutexHolder ) PRIVILEGED_FUNCTION;
3134 * Set the priority of a task back to its proper priority in the case that it
3135 * inherited a higher priority while it was holding a semaphore.
3137 BaseType_t xTaskPriorityDisinherit( TaskHandle_t const pxMutexHolder ) PRIVILEGED_FUNCTION;
3140 * If a higher priority task attempting to obtain a mutex caused a lower
3141 * priority task to inherit the higher priority task's priority - but the higher
3142 * priority task then timed out without obtaining the mutex, then the lower
3143 * priority task will disinherit the priority again - but only down as far as
3144 * the highest priority task that is still waiting for the mutex (if there were
3145 * more than one task waiting for the mutex).
3147 void vTaskPriorityDisinheritAfterTimeout( TaskHandle_t const pxMutexHolder,
3148 UBaseType_t uxHighestPriorityWaitingTask ) PRIVILEGED_FUNCTION;
3151 * Get the uxTaskNumber assigned to the task referenced by the xTask parameter.
3153 UBaseType_t uxTaskGetTaskNumber( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
3156 * Set the uxTaskNumber of the task referenced by the xTask parameter to
3159 void vTaskSetTaskNumber( TaskHandle_t xTask,
3160 const UBaseType_t uxHandle ) PRIVILEGED_FUNCTION;
3163 * Only available when configUSE_TICKLESS_IDLE is set to 1.
3164 * If tickless mode is being used, or a low power mode is implemented, then
3165 * the tick interrupt will not execute during idle periods. When this is the
3166 * case, the tick count value maintained by the scheduler needs to be kept up
3167 * to date with the actual execution time by being skipped forward by a time
3168 * equal to the idle period.
3170 void vTaskStepTick( TickType_t xTicksToJump ) PRIVILEGED_FUNCTION;
3173 * Only available when configUSE_TICKLESS_IDLE is set to 1.
3174 * Provided for use within portSUPPRESS_TICKS_AND_SLEEP() to allow the port
3175 * specific sleep function to determine if it is ok to proceed with the sleep,
3176 * and if it is ok to proceed, if it is ok to sleep indefinitely.
3178 * This function is necessary because portSUPPRESS_TICKS_AND_SLEEP() is only
3179 * called with the scheduler suspended, not from within a critical section. It
3180 * is therefore possible for an interrupt to request a context switch between
3181 * portSUPPRESS_TICKS_AND_SLEEP() and the low power mode actually being
3182 * entered. eTaskConfirmSleepModeStatus() should be called from a short
3183 * critical section between the timer being stopped and the sleep mode being
3184 * entered to ensure it is ok to proceed into the sleep mode.
3186 eSleepModeStatus eTaskConfirmSleepModeStatus( void ) PRIVILEGED_FUNCTION;
3189 * For internal use only. Increment the mutex held count when a mutex is
3190 * taken and return the handle of the task that has taken the mutex.
3192 TaskHandle_t pvTaskIncrementMutexHeldCount( void ) PRIVILEGED_FUNCTION;
3195 * For internal use only. Same as vTaskSetTimeOutState(), but without a critical
3198 void vTaskInternalSetTimeOutState( TimeOut_t * const pxTimeOut ) PRIVILEGED_FUNCTION;
3200 #if ( portUSING_MPU_WRAPPERS == 1 )
3203 * For internal use only. Get MPU settings associated with a task.
3205 xMPU_SETTINGS * xTaskGetMPUSettings( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
3207 #endif /* portUSING_MPU_WRAPPERS */
3210 #if ( ( portUSING_MPU_WRAPPERS == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) && ( configENABLE_ACCESS_CONTROL_LIST == 1 ) )
3213 * For internal use only. Grant/Revoke a task's access to a kernel object.
3215 void vGrantAccessToKernelObject( TaskHandle_t xExternalTaskHandle,
3216 int32_t lExternalKernelObjectHandle ) PRIVILEGED_FUNCTION;
3217 void vRevokeAccessToKernelObject( TaskHandle_t xExternalTaskHandle,
3218 int32_t lExternalKernelObjectHandle ) PRIVILEGED_FUNCTION;
3221 * For internal use only. Grant/Revoke a task's access to a kernel object.
3223 void vPortGrantAccessToKernelObject( TaskHandle_t xInternalTaskHandle,
3224 int32_t lInternalIndexOfKernelObject ) PRIVILEGED_FUNCTION;
3225 void vPortRevokeAccessToKernelObject( TaskHandle_t xInternalTaskHandle,
3226 int32_t lInternalIndexOfKernelObject ) PRIVILEGED_FUNCTION;
3228 #endif /* #if ( ( portUSING_MPU_WRAPPERS == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) && ( configENABLE_ACCESS_CONTROL_LIST == 1 ) ) */
3235 #endif /* INC_TASK_H */