/* * FreeRTOS Kernel V10.5.1 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * SPDX-FileCopyrightText: 2021 Amazon.com, Inc. or its affiliates * * SPDX-License-Identifier: MIT * * SPDX-FileContributor: 2023 Espressif Systems (Shanghai) CO LTD * * Permission is hereby granted, free of charge, to any person obtaining a copy of * this software and associated documentation files (the "Software"), to deal in * the Software without restriction, including without limitation the rights to * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of * the Software, and to permit persons to whom the Software is furnished to do so, * subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * https://www.FreeRTOS.org * https://github.com/FreeRTOS * */ #ifndef TIMERS_H #define TIMERS_H #ifndef INC_FREERTOS_H #error "include FreeRTOS.h must appear in source files before include timers.h" #endif /*lint -save -e537 This headers are only multiply included if the application code * happens to also be including task.h. */ #include "task.h" /*lint -restore */ /* *INDENT-OFF* */ #ifdef __cplusplus extern "C" { #endif /* *INDENT-ON* */ /*----------------------------------------------------------- * MACROS AND DEFINITIONS *----------------------------------------------------------*/ /* IDs for commands that can be sent/received on the timer queue. These are to * be used solely through the macros that make up the public software timer API, * as defined below. The commands that are sent from interrupts must use the * highest numbers as tmrFIRST_FROM_ISR_COMMAND is used to determine if the task * or interrupt version of the queue send function should be used. */ #define tmrCOMMAND_EXECUTE_CALLBACK_FROM_ISR ( ( BaseType_t ) -2 ) #define tmrCOMMAND_EXECUTE_CALLBACK ( ( BaseType_t ) -1 ) #define tmrCOMMAND_START_DONT_TRACE ( ( BaseType_t ) 0 ) #define tmrCOMMAND_START ( ( BaseType_t ) 1 ) #define tmrCOMMAND_RESET ( ( BaseType_t ) 2 ) #define tmrCOMMAND_STOP ( ( BaseType_t ) 3 ) #define tmrCOMMAND_CHANGE_PERIOD ( ( BaseType_t ) 4 ) #define tmrCOMMAND_DELETE ( ( BaseType_t ) 5 ) #define tmrFIRST_FROM_ISR_COMMAND ( ( BaseType_t ) 6 ) #define tmrCOMMAND_START_FROM_ISR ( ( BaseType_t ) 6 ) #define tmrCOMMAND_RESET_FROM_ISR ( ( BaseType_t ) 7 ) #define tmrCOMMAND_STOP_FROM_ISR ( ( BaseType_t ) 8 ) #define tmrCOMMAND_CHANGE_PERIOD_FROM_ISR ( ( BaseType_t ) 9 ) /** * Type by which software timers are referenced. For example, a call to * xTimerCreate() returns an TimerHandle_t variable that can then be used to * reference the subject timer in calls to other software timer API functions * (for example, xTimerStart(), xTimerReset(), etc.). */ struct tmrTimerControl; /* The old naming convention is used to prevent breaking kernel aware debuggers. */ typedef struct tmrTimerControl * TimerHandle_t; /* * Defines the prototype to which timer callback functions must conform. */ typedef void (* TimerCallbackFunction_t)( TimerHandle_t xTimer ); /* * Defines the prototype to which functions used with the * xTimerPendFunctionCallFromISR() function must conform. */ typedef void (* PendedFunction_t)( void *, uint32_t ); /** * TimerHandle_t xTimerCreate( const char * const pcTimerName, * TickType_t xTimerPeriodInTicks, * BaseType_t xAutoReload, * void * pvTimerID, * TimerCallbackFunction_t pxCallbackFunction ); * * Creates a new software timer instance, and returns a handle by which the * created software timer can be referenced. * * Internally, within the FreeRTOS implementation, software timers use a block * of memory, in which the timer data structure is stored. If a software timer * is created using xTimerCreate() then the required memory is automatically * dynamically allocated inside the xTimerCreate() function. (see * https://www.FreeRTOS.org/a00111.html). If a software timer is created using * xTimerCreateStatic() then the application writer must provide the memory that * will get used by the software timer. xTimerCreateStatic() therefore allows a * software timer to be created without using any dynamic memory allocation. * * Timers are created in the dormant state. The xTimerStart(), xTimerReset(), * xTimerStartFromISR(), xTimerResetFromISR(), xTimerChangePeriod() and * xTimerChangePeriodFromISR() API functions can all be used to transition a * timer into the active state. * * @param pcTimerName A text name that is assigned to the timer. This is done * purely to assist debugging. The kernel itself only ever references a timer * by its handle, and never by its name. * * @param xTimerPeriodInTicks The timer period. The time is defined in tick * periods so the constant portTICK_PERIOD_MS can be used to convert a time that * has been specified in milliseconds. For example, if the timer must expire * after 100 ticks, then xTimerPeriodInTicks should be set to 100. * Alternatively, if the timer must expire after 500ms, then xPeriod can be set * to ( 500 / portTICK_PERIOD_MS ) provided configTICK_RATE_HZ is less than or * equal to 1000. Time timer period must be greater than 0. * * @param xAutoReload If xAutoReload is set to pdTRUE then the timer will * expire repeatedly with a frequency set by the xTimerPeriodInTicks parameter. * If xAutoReload is set to pdFALSE then the timer will be a one-shot timer and * enter the dormant state after it expires. * * @param pvTimerID An identifier that is assigned to the timer being created. * Typically this would be used in the timer callback function to identify which * timer expired when the same callback function is assigned to more than one * timer. * * @param pxCallbackFunction The function to call when the timer expires. * Callback functions must have the prototype defined by TimerCallbackFunction_t, * which is "void vCallbackFunction( TimerHandle_t xTimer );". * * @return If the timer is successfully created then a handle to the newly * created timer is returned. If the timer cannot be created because there is * insufficient FreeRTOS heap remaining to allocate the timer * structures then NULL is returned. * * Example usage: * @verbatim * #define NUM_TIMERS 5 * * // An array to hold handles to the created timers. * TimerHandle_t xTimers[ NUM_TIMERS ]; * * // An array to hold a count of the number of times each timer expires. * int32_t lExpireCounters[ NUM_TIMERS ] = { 0 }; * * // Define a callback function that will be used by multiple timer instances. * // The callback function does nothing but count the number of times the * // associated timer expires, and stop the timer once the timer has expired * // 10 times. * void vTimerCallback( TimerHandle_t pxTimer ) * { * int32_t lArrayIndex; * const int32_t xMaxExpiryCountBeforeStopping = 10; * * // Optionally do something if the pxTimer parameter is NULL. * configASSERT( pxTimer ); * * // Which timer expired? * lArrayIndex = ( int32_t ) pvTimerGetTimerID( pxTimer ); * * // Increment the number of times that pxTimer has expired. * lExpireCounters[ lArrayIndex ] += 1; * * // If the timer has expired 10 times then stop it from running. * if( lExpireCounters[ lArrayIndex ] == xMaxExpiryCountBeforeStopping ) * { * // Do not use a block time if calling a timer API function from a * // timer callback function, as doing so could cause a deadlock! * xTimerStop( pxTimer, 0 ); * } * } * * void main( void ) * { * int32_t x; * * // Create then start some timers. Starting the timers before the scheduler * // has been started means the timers will start running immediately that * // the scheduler starts. * for( x = 0; x < NUM_TIMERS; x++ ) * { * xTimers[ x ] = xTimerCreate( "Timer", // Just a text name, not used by the kernel. * ( 100 * ( x + 1 ) ), // The timer period in ticks. * pdTRUE, // The timers will auto-reload themselves when they expire. * ( void * ) x, // Assign each timer a unique id equal to its array index. * vTimerCallback // Each timer calls the same callback when it expires. * ); * * if( xTimers[ x ] == NULL ) * { * // The timer was not created. * } * else * { * // Start the timer. No block time is specified, and even if one was * // it would be ignored because the scheduler has not yet been * // started. * if( xTimerStart( xTimers[ x ], 0 ) != pdPASS ) * { * // The timer could not be set into the Active state. * } * } * } * * // ... * // Create tasks here. * // ... * * // Starting the scheduler will start the timers running as they have already * // been set into the active state. * vTaskStartScheduler(); * * // Should not reach here. * for( ;; ); * } * @endverbatim */ #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) TimerHandle_t xTimerCreate( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */ const TickType_t xTimerPeriodInTicks, const BaseType_t xAutoReload, void * const pvTimerID, TimerCallbackFunction_t pxCallbackFunction ) PRIVILEGED_FUNCTION; #endif /** * TimerHandle_t xTimerCreateStatic(const char * const pcTimerName, * TickType_t xTimerPeriodInTicks, * BaseType_t xAutoReload, * void * pvTimerID, * TimerCallbackFunction_t pxCallbackFunction, * StaticTimer_t *pxTimerBuffer ); * * Creates a new software timer instance, and returns a handle by which the * created software timer can be referenced. * * Internally, within the FreeRTOS implementation, software timers use a block * of memory, in which the timer data structure is stored. If a software timer * is created using xTimerCreate() then the required memory is automatically * dynamically allocated inside the xTimerCreate() function. (see * https://www.FreeRTOS.org/a00111.html). If a software timer is created using * xTimerCreateStatic() then the application writer must provide the memory that * will get used by the software timer. xTimerCreateStatic() therefore allows a * software timer to be created without using any dynamic memory allocation. * * Timers are created in the dormant state. The xTimerStart(), xTimerReset(), * xTimerStartFromISR(), xTimerResetFromISR(), xTimerChangePeriod() and * xTimerChangePeriodFromISR() API functions can all be used to transition a * timer into the active state. * * @param pcTimerName A text name that is assigned to the timer. This is done * purely to assist debugging. The kernel itself only ever references a timer * by its handle, and never by its name. * * @param xTimerPeriodInTicks The timer period. The time is defined in tick * periods so the constant portTICK_PERIOD_MS can be used to convert a time that * has been specified in milliseconds. For example, if the timer must expire * after 100 ticks, then xTimerPeriodInTicks should be set to 100. * Alternatively, if the timer must expire after 500ms, then xPeriod can be set * to ( 500 / portTICK_PERIOD_MS ) provided configTICK_RATE_HZ is less than or * equal to 1000. The timer period must be greater than 0. * * @param xAutoReload If xAutoReload is set to pdTRUE then the timer will * expire repeatedly with a frequency set by the xTimerPeriodInTicks parameter. * If xAutoReload is set to pdFALSE then the timer will be a one-shot timer and * enter the dormant state after it expires. * * @param pvTimerID An identifier that is assigned to the timer being created. * Typically this would be used in the timer callback function to identify which * timer expired when the same callback function is assigned to more than one * timer. * * @param pxCallbackFunction The function to call when the timer expires. * Callback functions must have the prototype defined by TimerCallbackFunction_t, * which is "void vCallbackFunction( TimerHandle_t xTimer );". * * @param pxTimerBuffer Must point to a variable of type StaticTimer_t, which * will be then be used to hold the software timer's data structures, removing * the need for the memory to be allocated dynamically. * * @return If the timer is created then a handle to the created timer is * returned. If pxTimerBuffer was NULL then NULL is returned. * * Example usage: * @verbatim * * // The buffer used to hold the software timer's data structure. * static StaticTimer_t xTimerBuffer; * * // A variable that will be incremented by the software timer's callback * // function. * UBaseType_t uxVariableToIncrement = 0; * * // A software timer callback function that increments a variable passed to * // it when the software timer was created. After the 5th increment the * // callback function stops the software timer. * static void prvTimerCallback( TimerHandle_t xExpiredTimer ) * { * UBaseType_t *puxVariableToIncrement; * BaseType_t xReturned; * * // Obtain the address of the variable to increment from the timer ID. * puxVariableToIncrement = ( UBaseType_t * ) pvTimerGetTimerID( xExpiredTimer ); * * // Increment the variable to show the timer callback has executed. * ( *puxVariableToIncrement )++; * * // If this callback has executed the required number of times, stop the * // timer. * if( *puxVariableToIncrement == 5 ) * { * // This is called from a timer callback so must not block. * xTimerStop( xExpiredTimer, staticDONT_BLOCK ); * } * } * * * void main( void ) * { * // Create the software time. xTimerCreateStatic() has an extra parameter * // than the normal xTimerCreate() API function. The parameter is a pointer * // to the StaticTimer_t structure that will hold the software timer * // structure. If the parameter is passed as NULL then the structure will be * // allocated dynamically, just as if xTimerCreate() had been called. * xTimer = xTimerCreateStatic( "T1", // Text name for the task. Helps debugging only. Not used by FreeRTOS. * xTimerPeriod, // The period of the timer in ticks. * pdTRUE, // This is an auto-reload timer. * ( void * ) &uxVariableToIncrement, // A variable incremented by the software timer's callback function * prvTimerCallback, // The function to execute when the timer expires. * &xTimerBuffer ); // The buffer that will hold the software timer structure. * * // The scheduler has not started yet so a block time is not used. * xReturned = xTimerStart( xTimer, 0 ); * * // ... * // Create tasks here. * // ... * * // Starting the scheduler will start the timers running as they have already * // been set into the active state. * vTaskStartScheduler(); * * // Should not reach here. * for( ;; ); * } * @endverbatim */ #if ( configSUPPORT_STATIC_ALLOCATION == 1 ) TimerHandle_t xTimerCreateStatic( const char * const pcTimerName, /*lint !e971 Unqualified char types are allowed for strings and single characters only. */ const TickType_t xTimerPeriodInTicks, const BaseType_t xAutoReload, void * const pvTimerID, TimerCallbackFunction_t pxCallbackFunction, StaticTimer_t * pxTimerBuffer ) PRIVILEGED_FUNCTION; #endif /* configSUPPORT_STATIC_ALLOCATION */ /** * void *pvTimerGetTimerID( TimerHandle_t xTimer ); * * Returns the ID assigned to the timer. * * IDs are assigned to timers using the pvTimerID parameter of the call to * xTimerCreated() that was used to create the timer, and by calling the * vTimerSetTimerID() API function. * * If the same callback function is assigned to multiple timers then the timer * ID can be used as time specific (timer local) storage. * * @param xTimer The timer being queried. * * @return The ID assigned to the timer being queried. * * Example usage: * * See the xTimerCreate() API function example usage scenario. */ void * pvTimerGetTimerID( const TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; /** * void vTimerSetTimerID( TimerHandle_t xTimer, void *pvNewID ); * * Sets the ID assigned to the timer. * * IDs are assigned to timers using the pvTimerID parameter of the call to * xTimerCreated() that was used to create the timer. * * If the same callback function is assigned to multiple timers then the timer * ID can be used as time specific (timer local) storage. * * @param xTimer The timer being updated. * * @param pvNewID The ID to assign to the timer. * * Example usage: * * See the xTimerCreate() API function example usage scenario. */ void vTimerSetTimerID( TimerHandle_t xTimer, void * pvNewID ) PRIVILEGED_FUNCTION; /** * BaseType_t xTimerIsTimerActive( TimerHandle_t xTimer ); * * Queries a timer to see if it is active or dormant. * * A timer will be dormant if: * 1) It has been created but not started, or * 2) It is an expired one-shot timer that has not been restarted. * * Timers are created in the dormant state. The xTimerStart(), xTimerReset(), * xTimerStartFromISR(), xTimerResetFromISR(), xTimerChangePeriod() and * xTimerChangePeriodFromISR() API functions can all be used to transition a timer into the * active state. * * @param xTimer The timer being queried. * * @return pdFALSE will be returned if the timer is dormant. A value other than * pdFALSE will be returned if the timer is active. * * Example usage: * @verbatim * // This function assumes xTimer has already been created. * void vAFunction( TimerHandle_t xTimer ) * { * if( xTimerIsTimerActive( xTimer ) != pdFALSE ) // or more simply and equivalently "if( xTimerIsTimerActive( xTimer ) )" * { * // xTimer is active, do something. * } * else * { * // xTimer is not active, do something else. * } * } * @endverbatim */ BaseType_t xTimerIsTimerActive( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; /** * TaskHandle_t xTimerGetTimerDaemonTaskHandle( void ); * * Simply returns the handle of the timer service/daemon task. It it not valid * to call xTimerGetTimerDaemonTaskHandle() before the scheduler has been started. */ TaskHandle_t xTimerGetTimerDaemonTaskHandle( void ) PRIVILEGED_FUNCTION; /** * BaseType_t xTimerStart( TimerHandle_t xTimer, TickType_t xTicksToWait ); * * Timer functionality is provided by a timer service/daemon task. Many of the * public FreeRTOS timer API functions send commands to the timer service task * through a queue called the timer command queue. The timer command queue is * private to the kernel itself and is not directly accessible to application * code. The length of the timer command queue is set by the * configTIMER_QUEUE_LENGTH configuration constant. * * xTimerStart() starts a timer that was previously created using the * xTimerCreate() API function. If the timer had already been started and was * already in the active state, then xTimerStart() has equivalent functionality * to the xTimerReset() API function. * * Starting a timer ensures the timer is in the active state. If the timer * is not stopped, deleted, or reset in the mean time, the callback function * associated with the timer will get called 'n' ticks after xTimerStart() was * called, where 'n' is the timers defined period. * * It is valid to call xTimerStart() before the scheduler has been started, but * when this is done the timer will not actually start until the scheduler is * started, and the timers expiry time will be relative to when the scheduler is * started, not relative to when xTimerStart() was called. * * The configUSE_TIMERS configuration constant must be set to 1 for xTimerStart() * to be available. * * @param xTimer The handle of the timer being started/restarted. * * @param xTicksToWait Specifies the time, in ticks, that the calling task should * be held in the Blocked state to wait for the start command to be successfully * sent to the timer command queue, should the queue already be full when * xTimerStart() was called. xTicksToWait is ignored if xTimerStart() is called * before the scheduler is started. * * @return pdFAIL will be returned if the start command could not be sent to * the timer command queue even after xTicksToWait ticks had passed. pdPASS will * be returned if the command was successfully sent to the timer command queue. * When the command is actually processed will depend on the priority of the * timer service/daemon task relative to other tasks in the system, although the * timers expiry time is relative to when xTimerStart() is actually called. The * timer service/daemon task priority is set by the configTIMER_TASK_PRIORITY * configuration constant. * * Example usage: * * See the xTimerCreate() API function example usage scenario. * */ #define xTimerStart( xTimer, xTicksToWait ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_START, ( xTaskGetTickCount() ), NULL, ( xTicksToWait ) ) /** * BaseType_t xTimerStop( TimerHandle_t xTimer, TickType_t xTicksToWait ); * * Timer functionality is provided by a timer service/daemon task. Many of the * public FreeRTOS timer API functions send commands to the timer service task * through a queue called the timer command queue. The timer command queue is * private to the kernel itself and is not directly accessible to application * code. The length of the timer command queue is set by the * configTIMER_QUEUE_LENGTH configuration constant. * * xTimerStop() stops a timer that was previously started using either of the * The xTimerStart(), xTimerReset(), xTimerStartFromISR(), xTimerResetFromISR(), * xTimerChangePeriod() or xTimerChangePeriodFromISR() API functions. * * Stopping a timer ensures the timer is not in the active state. * * The configUSE_TIMERS configuration constant must be set to 1 for xTimerStop() * to be available. * * @param xTimer The handle of the timer being stopped. * * @param xTicksToWait Specifies the time, in ticks, that the calling task should * be held in the Blocked state to wait for the stop command to be successfully * sent to the timer command queue, should the queue already be full when * xTimerStop() was called. xTicksToWait is ignored if xTimerStop() is called * before the scheduler is started. * * @return pdFAIL will be returned if the stop command could not be sent to * the timer command queue even after xTicksToWait ticks had passed. pdPASS will * be returned if the command was successfully sent to the timer command queue. * When the command is actually processed will depend on the priority of the * timer service/daemon task relative to other tasks in the system. The timer * service/daemon task priority is set by the configTIMER_TASK_PRIORITY * configuration constant. * * Example usage: * * See the xTimerCreate() API function example usage scenario. * */ #define xTimerStop( xTimer, xTicksToWait ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_STOP, 0U, NULL, ( xTicksToWait ) ) /** * BaseType_t xTimerChangePeriod( TimerHandle_t xTimer, * TickType_t xNewPeriod, * TickType_t xTicksToWait ); * * Timer functionality is provided by a timer service/daemon task. Many of the * public FreeRTOS timer API functions send commands to the timer service task * through a queue called the timer command queue. The timer command queue is * private to the kernel itself and is not directly accessible to application * code. The length of the timer command queue is set by the * configTIMER_QUEUE_LENGTH configuration constant. * * xTimerChangePeriod() changes the period of a timer that was previously * created using the xTimerCreate() API function. * * xTimerChangePeriod() can be called to change the period of an active or * dormant state timer. * * The configUSE_TIMERS configuration constant must be set to 1 for * xTimerChangePeriod() to be available. * * @param xTimer The handle of the timer that is having its period changed. * * @param xNewPeriod The new period for xTimer. Timer periods are specified in * tick periods, so the constant portTICK_PERIOD_MS can be used to convert a time * that has been specified in milliseconds. For example, if the timer must * expire after 100 ticks, then xNewPeriod should be set to 100. Alternatively, * if the timer must expire after 500ms, then xNewPeriod can be set to * ( 500 / portTICK_PERIOD_MS ) provided configTICK_RATE_HZ is less than * or equal to 1000. * * @param xTicksToWait Specifies the time, in ticks, that the calling task should * be held in the Blocked state to wait for the change period command to be * successfully sent to the timer command queue, should the queue already be * full when xTimerChangePeriod() was called. xTicksToWait is ignored if * xTimerChangePeriod() is called before the scheduler is started. * * @return pdFAIL will be returned if the change period command could not be * sent to the timer command queue even after xTicksToWait ticks had passed. * pdPASS will be returned if the command was successfully sent to the timer * command queue. When the command is actually processed will depend on the * priority of the timer service/daemon task relative to other tasks in the * system. The timer service/daemon task priority is set by the * configTIMER_TASK_PRIORITY configuration constant. * * Example usage: * @verbatim * // This function assumes xTimer has already been created. If the timer * // referenced by xTimer is already active when it is called, then the timer * // is deleted. If the timer referenced by xTimer is not active when it is * // called, then the period of the timer is set to 500ms and the timer is * // started. * void vAFunction( TimerHandle_t xTimer ) * { * if( xTimerIsTimerActive( xTimer ) != pdFALSE ) // or more simply and equivalently "if( xTimerIsTimerActive( xTimer ) )" * { * // xTimer is already active - delete it. * xTimerDelete( xTimer ); * } * else * { * // xTimer is not active, change its period to 500ms. This will also * // cause the timer to start. Block for a maximum of 100 ticks if the * // change period command cannot immediately be sent to the timer * // command queue. * if( xTimerChangePeriod( xTimer, 500 / portTICK_PERIOD_MS, 100 ) == pdPASS ) * { * // The command was successfully sent. * } * else * { * // The command could not be sent, even after waiting for 100 ticks * // to pass. Take appropriate action here. * } * } * } * @endverbatim */ #define xTimerChangePeriod( xTimer, xNewPeriod, xTicksToWait ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_CHANGE_PERIOD, ( xNewPeriod ), NULL, ( xTicksToWait ) ) /** * BaseType_t xTimerDelete( TimerHandle_t xTimer, TickType_t xTicksToWait ); * * Timer functionality is provided by a timer service/daemon task. Many of the * public FreeRTOS timer API functions send commands to the timer service task * through a queue called the timer command queue. The timer command queue is * private to the kernel itself and is not directly accessible to application * code. The length of the timer command queue is set by the * configTIMER_QUEUE_LENGTH configuration constant. * * xTimerDelete() deletes a timer that was previously created using the * xTimerCreate() API function. * * The configUSE_TIMERS configuration constant must be set to 1 for * xTimerDelete() to be available. * * @param xTimer The handle of the timer being deleted. * * @param xTicksToWait Specifies the time, in ticks, that the calling task should * be held in the Blocked state to wait for the delete command to be * successfully sent to the timer command queue, should the queue already be * full when xTimerDelete() was called. xTicksToWait is ignored if xTimerDelete() * is called before the scheduler is started. * * @return pdFAIL will be returned if the delete command could not be sent to * the timer command queue even after xTicksToWait ticks had passed. pdPASS will * be returned if the command was successfully sent to the timer command queue. * When the command is actually processed will depend on the priority of the * timer service/daemon task relative to other tasks in the system. The timer * service/daemon task priority is set by the configTIMER_TASK_PRIORITY * configuration constant. * * Example usage: * * See the xTimerChangePeriod() API function example usage scenario. */ #define xTimerDelete( xTimer, xTicksToWait ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_DELETE, 0U, NULL, ( xTicksToWait ) ) /** * BaseType_t xTimerReset( TimerHandle_t xTimer, TickType_t xTicksToWait ); * * Timer functionality is provided by a timer service/daemon task. Many of the * public FreeRTOS timer API functions send commands to the timer service task * through a queue called the timer command queue. The timer command queue is * private to the kernel itself and is not directly accessible to application * code. The length of the timer command queue is set by the * configTIMER_QUEUE_LENGTH configuration constant. * * xTimerReset() re-starts a timer that was previously created using the * xTimerCreate() API function. If the timer had already been started and was * already in the active state, then xTimerReset() will cause the timer to * re-evaluate its expiry time so that it is relative to when xTimerReset() was * called. If the timer was in the dormant state then xTimerReset() has * equivalent functionality to the xTimerStart() API function. * * Resetting a timer ensures the timer is in the active state. If the timer * is not stopped, deleted, or reset in the mean time, the callback function * associated with the timer will get called 'n' ticks after xTimerReset() was * called, where 'n' is the timers defined period. * * It is valid to call xTimerReset() before the scheduler has been started, but * when this is done the timer will not actually start until the scheduler is * started, and the timers expiry time will be relative to when the scheduler is * started, not relative to when xTimerReset() was called. * * The configUSE_TIMERS configuration constant must be set to 1 for xTimerReset() * to be available. * * @param xTimer The handle of the timer being reset/started/restarted. * * @param xTicksToWait Specifies the time, in ticks, that the calling task should * be held in the Blocked state to wait for the reset command to be successfully * sent to the timer command queue, should the queue already be full when * xTimerReset() was called. xTicksToWait is ignored if xTimerReset() is called * before the scheduler is started. * * @return pdFAIL will be returned if the reset command could not be sent to * the timer command queue even after xTicksToWait ticks had passed. pdPASS will * be returned if the command was successfully sent to the timer command queue. * When the command is actually processed will depend on the priority of the * timer service/daemon task relative to other tasks in the system, although the * timers expiry time is relative to when xTimerStart() is actually called. The * timer service/daemon task priority is set by the configTIMER_TASK_PRIORITY * configuration constant. * * Example usage: * @verbatim * // When a key is pressed, an LCD back-light is switched on. If 5 seconds pass * // without a key being pressed, then the LCD back-light is switched off. In * // this case, the timer is a one-shot timer. * * TimerHandle_t xBacklightTimer = NULL; * * // The callback function assigned to the one-shot timer. In this case the * // parameter is not used. * void vBacklightTimerCallback( TimerHandle_t pxTimer ) * { * // The timer expired, therefore 5 seconds must have passed since a key * // was pressed. Switch off the LCD back-light. * vSetBacklightState( BACKLIGHT_OFF ); * } * * // The key press event handler. * void vKeyPressEventHandler( char cKey ) * { * // Ensure the LCD back-light is on, then reset the timer that is * // responsible for turning the back-light off after 5 seconds of * // key inactivity. Wait 10 ticks for the command to be successfully sent * // if it cannot be sent immediately. * vSetBacklightState( BACKLIGHT_ON ); * if( xTimerReset( xBacklightTimer, 100 ) != pdPASS ) * { * // The reset command was not executed successfully. Take appropriate * // action here. * } * * // Perform the rest of the key processing here. * } * * void main( void ) * { * int32_t x; * * // Create then start the one-shot timer that is responsible for turning * // the back-light off if no keys are pressed within a 5 second period. * xBacklightTimer = xTimerCreate( "BacklightTimer", // Just a text name, not used by the kernel. * ( 5000 / portTICK_PERIOD_MS), // The timer period in ticks. * pdFALSE, // The timer is a one-shot timer. * 0, // The id is not used by the callback so can take any value. * vBacklightTimerCallback // The callback function that switches the LCD back-light off. * ); * * if( xBacklightTimer == NULL ) * { * // The timer was not created. * } * else * { * // Start the timer. No block time is specified, and even if one was * // it would be ignored because the scheduler has not yet been * // started. * if( xTimerStart( xBacklightTimer, 0 ) != pdPASS ) * { * // The timer could not be set into the Active state. * } * } * * // ... * // Create tasks here. * // ... * * // Starting the scheduler will start the timer running as it has already * // been set into the active state. * vTaskStartScheduler(); * * // Should not reach here. * for( ;; ); * } * @endverbatim */ #define xTimerReset( xTimer, xTicksToWait ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_RESET, ( xTaskGetTickCount() ), NULL, ( xTicksToWait ) ) /** * BaseType_t xTimerStartFromISR( TimerHandle_t xTimer, * BaseType_t *pxHigherPriorityTaskWoken ); * * A version of xTimerStart() that can be called from an interrupt service * routine. * * @param xTimer The handle of the timer being started/restarted. * * @param pxHigherPriorityTaskWoken The timer service/daemon task spends most * of its time in the Blocked state, waiting for messages to arrive on the timer * command queue. Calling xTimerStartFromISR() writes a message to the timer * command queue, so has the potential to transition the timer service/daemon * task out of the Blocked state. If calling xTimerStartFromISR() causes the * timer service/daemon task to leave the Blocked state, and the timer service/ * daemon task has a priority equal to or greater than the currently executing * task (the task that was interrupted), then *pxHigherPriorityTaskWoken will * get set to pdTRUE internally within the xTimerStartFromISR() function. If * xTimerStartFromISR() sets this value to pdTRUE then a context switch should * be performed before the interrupt exits. * * @return pdFAIL will be returned if the start command could not be sent to * the timer command queue. pdPASS will be returned if the command was * successfully sent to the timer command queue. When the command is actually * processed will depend on the priority of the timer service/daemon task * relative to other tasks in the system, although the timers expiry time is * relative to when xTimerStartFromISR() is actually called. The timer * service/daemon task priority is set by the configTIMER_TASK_PRIORITY * configuration constant. * * Example usage: * @verbatim * // This scenario assumes xBacklightTimer has already been created. When a * // key is pressed, an LCD back-light is switched on. If 5 seconds pass * // without a key being pressed, then the LCD back-light is switched off. In * // this case, the timer is a one-shot timer, and unlike the example given for * // the xTimerReset() function, the key press event handler is an interrupt * // service routine. * * // The callback function assigned to the one-shot timer. In this case the * // parameter is not used. * void vBacklightTimerCallback( TimerHandle_t pxTimer ) * { * // The timer expired, therefore 5 seconds must have passed since a key * // was pressed. Switch off the LCD back-light. * vSetBacklightState( BACKLIGHT_OFF ); * } * * // The key press interrupt service routine. * void vKeyPressEventInterruptHandler( void ) * { * BaseType_t xHigherPriorityTaskWoken = pdFALSE; * * // Ensure the LCD back-light is on, then restart the timer that is * // responsible for turning the back-light off after 5 seconds of * // key inactivity. This is an interrupt service routine so can only * // call FreeRTOS API functions that end in "FromISR". * vSetBacklightState( BACKLIGHT_ON ); * * // xTimerStartFromISR() or xTimerResetFromISR() could be called here * // as both cause the timer to re-calculate its expiry time. * // xHigherPriorityTaskWoken was initialised to pdFALSE when it was * // declared (in this function). * if( xTimerStartFromISR( xBacklightTimer, &xHigherPriorityTaskWoken ) != pdPASS ) * { * // The start command was not executed successfully. Take appropriate * // action here. * } * * // Perform the rest of the key processing here. * * // If xHigherPriorityTaskWoken equals pdTRUE, then a context switch * // should be performed. The syntax required to perform a context switch * // from inside an ISR varies from port to port, and from compiler to * // compiler. Inspect the demos for the port you are using to find the * // actual syntax required. * if( xHigherPriorityTaskWoken != pdFALSE ) * { * // Call the interrupt safe yield function here (actual function * // depends on the FreeRTOS port being used). * } * } * @endverbatim */ #define xTimerStartFromISR( xTimer, pxHigherPriorityTaskWoken ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_START_FROM_ISR, ( xTaskGetTickCountFromISR() ), ( pxHigherPriorityTaskWoken ), 0U ) /** * BaseType_t xTimerStopFromISR( TimerHandle_t xTimer, * BaseType_t *pxHigherPriorityTaskWoken ); * * A version of xTimerStop() that can be called from an interrupt service * routine. * * @param xTimer The handle of the timer being stopped. * * @param pxHigherPriorityTaskWoken The timer service/daemon task spends most * of its time in the Blocked state, waiting for messages to arrive on the timer * command queue. Calling xTimerStopFromISR() writes a message to the timer * command queue, so has the potential to transition the timer service/daemon * task out of the Blocked state. If calling xTimerStopFromISR() causes the * timer service/daemon task to leave the Blocked state, and the timer service/ * daemon task has a priority equal to or greater than the currently executing * task (the task that was interrupted), then *pxHigherPriorityTaskWoken will * get set to pdTRUE internally within the xTimerStopFromISR() function. If * xTimerStopFromISR() sets this value to pdTRUE then a context switch should * be performed before the interrupt exits. * * @return pdFAIL will be returned if the stop command could not be sent to * the timer command queue. pdPASS will be returned if the command was * successfully sent to the timer command queue. When the command is actually * processed will depend on the priority of the timer service/daemon task * relative to other tasks in the system. The timer service/daemon task * priority is set by the configTIMER_TASK_PRIORITY configuration constant. * * Example usage: * @verbatim * // This scenario assumes xTimer has already been created and started. When * // an interrupt occurs, the timer should be simply stopped. * * // The interrupt service routine that stops the timer. * void vAnExampleInterruptServiceRoutine( void ) * { * BaseType_t xHigherPriorityTaskWoken = pdFALSE; * * // The interrupt has occurred - simply stop the timer. * // xHigherPriorityTaskWoken was set to pdFALSE where it was defined * // (within this function). As this is an interrupt service routine, only * // FreeRTOS API functions that end in "FromISR" can be used. * if( xTimerStopFromISR( xTimer, &xHigherPriorityTaskWoken ) != pdPASS ) * { * // The stop command was not executed successfully. Take appropriate * // action here. * } * * // If xHigherPriorityTaskWoken equals pdTRUE, then a context switch * // should be performed. The syntax required to perform a context switch * // from inside an ISR varies from port to port, and from compiler to * // compiler. Inspect the demos for the port you are using to find the * // actual syntax required. * if( xHigherPriorityTaskWoken != pdFALSE ) * { * // Call the interrupt safe yield function here (actual function * // depends on the FreeRTOS port being used). * } * } * @endverbatim */ #define xTimerStopFromISR( xTimer, pxHigherPriorityTaskWoken ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_STOP_FROM_ISR, 0, ( pxHigherPriorityTaskWoken ), 0U ) /** * BaseType_t xTimerChangePeriodFromISR( TimerHandle_t xTimer, * TickType_t xNewPeriod, * BaseType_t *pxHigherPriorityTaskWoken ); * * A version of xTimerChangePeriod() that can be called from an interrupt * service routine. * * @param xTimer The handle of the timer that is having its period changed. * * @param xNewPeriod The new period for xTimer. Timer periods are specified in * tick periods, so the constant portTICK_PERIOD_MS can be used to convert a time * that has been specified in milliseconds. For example, if the timer must * expire after 100 ticks, then xNewPeriod should be set to 100. Alternatively, * if the timer must expire after 500ms, then xNewPeriod can be set to * ( 500 / portTICK_PERIOD_MS ) provided configTICK_RATE_HZ is less than * or equal to 1000. * * @param pxHigherPriorityTaskWoken The timer service/daemon task spends most * of its time in the Blocked state, waiting for messages to arrive on the timer * command queue. Calling xTimerChangePeriodFromISR() writes a message to the * timer command queue, so has the potential to transition the timer service/ * daemon task out of the Blocked state. If calling xTimerChangePeriodFromISR() * causes the timer service/daemon task to leave the Blocked state, and the * timer service/daemon task has a priority equal to or greater than the * currently executing task (the task that was interrupted), then * *pxHigherPriorityTaskWoken will get set to pdTRUE internally within the * xTimerChangePeriodFromISR() function. If xTimerChangePeriodFromISR() sets * this value to pdTRUE then a context switch should be performed before the * interrupt exits. * * @return pdFAIL will be returned if the command to change the timers period * could not be sent to the timer command queue. pdPASS will be returned if the * command was successfully sent to the timer command queue. When the command * is actually processed will depend on the priority of the timer service/daemon * task relative to other tasks in the system. The timer service/daemon task * priority is set by the configTIMER_TASK_PRIORITY configuration constant. * * Example usage: * @verbatim * // This scenario assumes xTimer has already been created and started. When * // an interrupt occurs, the period of xTimer should be changed to 500ms. * * // The interrupt service routine that changes the period of xTimer. * void vAnExampleInterruptServiceRoutine( void ) * { * BaseType_t xHigherPriorityTaskWoken = pdFALSE; * * // The interrupt has occurred - change the period of xTimer to 500ms. * // xHigherPriorityTaskWoken was set to pdFALSE where it was defined * // (within this function). As this is an interrupt service routine, only * // FreeRTOS API functions that end in "FromISR" can be used. * if( xTimerChangePeriodFromISR( xTimer, &xHigherPriorityTaskWoken ) != pdPASS ) * { * // The command to change the timers period was not executed * // successfully. Take appropriate action here. * } * * // If xHigherPriorityTaskWoken equals pdTRUE, then a context switch * // should be performed. The syntax required to perform a context switch * // from inside an ISR varies from port to port, and from compiler to * // compiler. Inspect the demos for the port you are using to find the * // actual syntax required. * if( xHigherPriorityTaskWoken != pdFALSE ) * { * // Call the interrupt safe yield function here (actual function * // depends on the FreeRTOS port being used). * } * } * @endverbatim */ #define xTimerChangePeriodFromISR( xTimer, xNewPeriod, pxHigherPriorityTaskWoken ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_CHANGE_PERIOD_FROM_ISR, ( xNewPeriod ), ( pxHigherPriorityTaskWoken ), 0U ) /** * BaseType_t xTimerResetFromISR( TimerHandle_t xTimer, * BaseType_t *pxHigherPriorityTaskWoken ); * * A version of xTimerReset() that can be called from an interrupt service * routine. * * @param xTimer The handle of the timer that is to be started, reset, or * restarted. * * @param pxHigherPriorityTaskWoken The timer service/daemon task spends most * of its time in the Blocked state, waiting for messages to arrive on the timer * command queue. Calling xTimerResetFromISR() writes a message to the timer * command queue, so has the potential to transition the timer service/daemon * task out of the Blocked state. If calling xTimerResetFromISR() causes the * timer service/daemon task to leave the Blocked state, and the timer service/ * daemon task has a priority equal to or greater than the currently executing * task (the task that was interrupted), then *pxHigherPriorityTaskWoken will * get set to pdTRUE internally within the xTimerResetFromISR() function. If * xTimerResetFromISR() sets this value to pdTRUE then a context switch should * be performed before the interrupt exits. * * @return pdFAIL will be returned if the reset command could not be sent to * the timer command queue. pdPASS will be returned if the command was * successfully sent to the timer command queue. When the command is actually * processed will depend on the priority of the timer service/daemon task * relative to other tasks in the system, although the timers expiry time is * relative to when xTimerResetFromISR() is actually called. The timer service/daemon * task priority is set by the configTIMER_TASK_PRIORITY configuration constant. * * Example usage: * @verbatim * // This scenario assumes xBacklightTimer has already been created. When a * // key is pressed, an LCD back-light is switched on. If 5 seconds pass * // without a key being pressed, then the LCD back-light is switched off. In * // this case, the timer is a one-shot timer, and unlike the example given for * // the xTimerReset() function, the key press event handler is an interrupt * // service routine. * * // The callback function assigned to the one-shot timer. In this case the * // parameter is not used. * void vBacklightTimerCallback( TimerHandle_t pxTimer ) * { * // The timer expired, therefore 5 seconds must have passed since a key * // was pressed. Switch off the LCD back-light. * vSetBacklightState( BACKLIGHT_OFF ); * } * * // The key press interrupt service routine. * void vKeyPressEventInterruptHandler( void ) * { * BaseType_t xHigherPriorityTaskWoken = pdFALSE; * * // Ensure the LCD back-light is on, then reset the timer that is * // responsible for turning the back-light off after 5 seconds of * // key inactivity. This is an interrupt service routine so can only * // call FreeRTOS API functions that end in "FromISR". * vSetBacklightState( BACKLIGHT_ON ); * * // xTimerStartFromISR() or xTimerResetFromISR() could be called here * // as both cause the timer to re-calculate its expiry time. * // xHigherPriorityTaskWoken was initialised to pdFALSE when it was * // declared (in this function). * if( xTimerResetFromISR( xBacklightTimer, &xHigherPriorityTaskWoken ) != pdPASS ) * { * // The reset command was not executed successfully. Take appropriate * // action here. * } * * // Perform the rest of the key processing here. * * // If xHigherPriorityTaskWoken equals pdTRUE, then a context switch * // should be performed. The syntax required to perform a context switch * // from inside an ISR varies from port to port, and from compiler to * // compiler. Inspect the demos for the port you are using to find the * // actual syntax required. * if( xHigherPriorityTaskWoken != pdFALSE ) * { * // Call the interrupt safe yield function here (actual function * // depends on the FreeRTOS port being used). * } * } * @endverbatim */ #define xTimerResetFromISR( xTimer, pxHigherPriorityTaskWoken ) \ xTimerGenericCommand( ( xTimer ), tmrCOMMAND_RESET_FROM_ISR, ( xTaskGetTickCountFromISR() ), ( pxHigherPriorityTaskWoken ), 0U ) /** * BaseType_t xTimerPendFunctionCallFromISR( PendedFunction_t xFunctionToPend, * void *pvParameter1, * uint32_t ulParameter2, * BaseType_t *pxHigherPriorityTaskWoken ); * * * Used from application interrupt service routines to defer the execution of a * function to the RTOS daemon task (the timer service task, hence this function * is implemented in timers.c and is prefixed with 'Timer'). * * Ideally an interrupt service routine (ISR) is kept as short as possible, but * sometimes an ISR either has a lot of processing to do, or needs to perform * processing that is not deterministic. In these cases * xTimerPendFunctionCallFromISR() can be used to defer processing of a function * to the RTOS daemon task. * * A mechanism is provided that allows the interrupt to return directly to the * task that will subsequently execute the pended callback function. This * allows the callback function to execute contiguously in time with the * interrupt - just as if the callback had executed in the interrupt itself. * * @param xFunctionToPend The function to execute from the timer service/ * daemon task. The function must conform to the PendedFunction_t * prototype. * * @param pvParameter1 The value of the callback function's first parameter. * The parameter has a void * type to allow it to be used to pass any type. * For example, unsigned longs can be cast to a void *, or the void * can be * used to point to a structure. * * @param ulParameter2 The value of the callback function's second parameter. * * @param pxHigherPriorityTaskWoken As mentioned above, calling this function * will result in a message being sent to the timer daemon task. If the * priority of the timer daemon task (which is set using * configTIMER_TASK_PRIORITY in FreeRTOSConfig.h) is higher than the priority of * the currently running task (the task the interrupt interrupted) then * *pxHigherPriorityTaskWoken will be set to pdTRUE within * xTimerPendFunctionCallFromISR(), indicating that a context switch should be * requested before the interrupt exits. For that reason * *pxHigherPriorityTaskWoken must be initialised to pdFALSE. See the * example code below. * * @return pdPASS is returned if the message was successfully sent to the * timer daemon task, otherwise pdFALSE is returned. * * Example usage: * @verbatim * * // The callback function that will execute in the context of the daemon task. * // Note callback functions must all use this same prototype. * void vProcessInterface( void *pvParameter1, uint32_t ulParameter2 ) * { * BaseType_t xInterfaceToService; * * // The interface that requires servicing is passed in the second * // parameter. The first parameter is not used in this case. * xInterfaceToService = ( BaseType_t ) ulParameter2; * * // ...Perform the processing here... * } * * // An ISR that receives data packets from multiple interfaces * void vAnISR( void ) * { * BaseType_t xInterfaceToService, xHigherPriorityTaskWoken; * * // Query the hardware to determine which interface needs processing. * xInterfaceToService = prvCheckInterfaces(); * * // The actual processing is to be deferred to a task. Request the * // vProcessInterface() callback function is executed, passing in the * // number of the interface that needs processing. The interface to * // service is passed in the second parameter. The first parameter is * // not used in this case. * xHigherPriorityTaskWoken = pdFALSE; * xTimerPendFunctionCallFromISR( vProcessInterface, NULL, ( uint32_t ) xInterfaceToService, &xHigherPriorityTaskWoken ); * * // If xHigherPriorityTaskWoken is now set to pdTRUE then a context * // switch should be requested. The macro used is port specific and will * // be either portYIELD_FROM_ISR() or portEND_SWITCHING_ISR() - refer to * // the documentation page for the port being used. * portYIELD_FROM_ISR( xHigherPriorityTaskWoken ); * * } * @endverbatim */ BaseType_t xTimerPendFunctionCallFromISR( PendedFunction_t xFunctionToPend, void * pvParameter1, uint32_t ulParameter2, BaseType_t * pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION; /** * BaseType_t xTimerPendFunctionCall( PendedFunction_t xFunctionToPend, * void *pvParameter1, * uint32_t ulParameter2, * TickType_t xTicksToWait ); * * * Used to defer the execution of a function to the RTOS daemon task (the timer * service task, hence this function is implemented in timers.c and is prefixed * with 'Timer'). * * @param xFunctionToPend The function to execute from the timer service/ * daemon task. The function must conform to the PendedFunction_t * prototype. * * @param pvParameter1 The value of the callback function's first parameter. * The parameter has a void * type to allow it to be used to pass any type. * For example, unsigned longs can be cast to a void *, or the void * can be * used to point to a structure. * * @param ulParameter2 The value of the callback function's second parameter. * * @param xTicksToWait Calling this function will result in a message being * sent to the timer daemon task on a queue. xTicksToWait is the amount of * time the calling task should remain in the Blocked state (so not using any * processing time) for space to become available on the timer queue if the * queue is found to be full. * * @return pdPASS is returned if the message was successfully sent to the * timer daemon task, otherwise pdFALSE is returned. * */ BaseType_t xTimerPendFunctionCall( PendedFunction_t xFunctionToPend, void * pvParameter1, uint32_t ulParameter2, TickType_t xTicksToWait ) PRIVILEGED_FUNCTION; /** * const char * const pcTimerGetName( TimerHandle_t xTimer ); * * Returns the name that was assigned to a timer when the timer was created. * * @param xTimer The handle of the timer being queried. * * @return The name assigned to the timer specified by the xTimer parameter. */ const char * pcTimerGetName( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */ /** * void vTimerSetReloadMode( TimerHandle_t xTimer, const BaseType_t xAutoReload ); * * Updates a timer to be either an auto-reload timer, in which case the timer * automatically resets itself each time it expires, or a one-shot timer, in * which case the timer will only expire once unless it is manually restarted. * * @param xTimer The handle of the timer being updated. * * @param xAutoReload If xAutoReload is set to pdTRUE then the timer will * expire repeatedly with a frequency set by the timer's period (see the * xTimerPeriodInTicks parameter of the xTimerCreate() API function). If * xAutoReload is set to pdFALSE then the timer will be a one-shot timer and * enter the dormant state after it expires. */ void vTimerSetReloadMode( TimerHandle_t xTimer, const BaseType_t xAutoReload ) PRIVILEGED_FUNCTION; /** * BaseType_t xTimerGetReloadMode( TimerHandle_t xTimer ); * * Queries a timer to determine if it is an auto-reload timer, in which case the timer * automatically resets itself each time it expires, or a one-shot timer, in * which case the timer will only expire once unless it is manually restarted. * * @param xTimer The handle of the timer being queried. * * @return If the timer is an auto-reload timer then pdTRUE is returned, otherwise * pdFALSE is returned. */ BaseType_t xTimerGetReloadMode( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; /** * UBaseType_t uxTimerGetReloadMode( TimerHandle_t xTimer ); * * Queries a timer to determine if it is an auto-reload timer, in which case the timer * automatically resets itself each time it expires, or a one-shot timer, in * which case the timer will only expire once unless it is manually restarted. * * @param xTimer The handle of the timer being queried. * * @return If the timer is an auto-reload timer then pdTRUE is returned, otherwise * pdFALSE is returned. */ UBaseType_t uxTimerGetReloadMode( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; /** * TickType_t xTimerGetPeriod( TimerHandle_t xTimer ); * * Returns the period of a timer. * * @param xTimer The handle of the timer being queried. * * @return The period of the timer in ticks. */ TickType_t xTimerGetPeriod( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; /** * TickType_t xTimerGetExpiryTime( TimerHandle_t xTimer ); * * Returns the time in ticks at which the timer will expire. If this is less * than the current tick count then the expiry time has overflowed from the * current time. * * @param xTimer The handle of the timer being queried. * * @return If the timer is running then the time in ticks at which the timer * will next expire is returned. If the timer is not running then the return * value is undefined. */ TickType_t xTimerGetExpiryTime( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; /* * Functions beyond this part are not part of the public API and are intended * for use by the kernel only. */ BaseType_t xTimerCreateTimerTask( void ) PRIVILEGED_FUNCTION; BaseType_t xTimerGenericCommand( TimerHandle_t xTimer, const BaseType_t xCommandID, const TickType_t xOptionalValue, BaseType_t * const pxHigherPriorityTaskWoken, const TickType_t xTicksToWait ) PRIVILEGED_FUNCTION; #if ( configUSE_TRACE_FACILITY == 1 ) void vTimerSetTimerNumber( TimerHandle_t xTimer, UBaseType_t uxTimerNumber ) PRIVILEGED_FUNCTION; UBaseType_t uxTimerGetTimerNumber( TimerHandle_t xTimer ) PRIVILEGED_FUNCTION; #endif #if ( configSUPPORT_STATIC_ALLOCATION == 1 ) /** * task.h * @code{c} * void vApplicationGetTimerTaskMemory( StaticTask_t ** ppxTimerTaskTCBBuffer, StackType_t ** ppxTimerTaskStackBuffer, uint32_t *pulTimerTaskStackSize ) * @endcode * * This function is used to provide a statically allocated block of memory to FreeRTOS to hold the Timer Task TCB. This function is required when * configSUPPORT_STATIC_ALLOCATION is set. For more information see this URI: https://www.FreeRTOS.org/a00110.html#configSUPPORT_STATIC_ALLOCATION * * @param ppxTimerTaskTCBBuffer A handle to a statically allocated TCB buffer * @param ppxTimerTaskStackBuffer A handle to a statically allocated Stack buffer for the idle task * @param pulTimerTaskStackSize A pointer to the number of elements that will fit in the allocated stack buffer */ void vApplicationGetTimerTaskMemory( StaticTask_t ** ppxTimerTaskTCBBuffer, StackType_t ** ppxTimerTaskStackBuffer, uint32_t * pulTimerTaskStackSize ); #endif /* *INDENT-OFF* */ #ifdef __cplusplus } #endif /* *INDENT-ON* */ #endif /* TIMERS_H */