2 FreeRTOS V7.1.0 - Copyright (C) 2011 Real Time Engineers Ltd.
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5 ***************************************************************************
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7 * FreeRTOS tutorial books are available in pdf and paperback. *
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8 * Complete, revised, and edited pdf reference manuals are also *
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11 * Purchasing FreeRTOS documentation will not only help you, by *
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12 * ensuring you get running as quickly as possible and with an *
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13 * in-depth knowledge of how to use FreeRTOS, it will also help *
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14 * the FreeRTOS project to continue with its mission of providing *
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15 * professional grade, cross platform, de facto standard solutions *
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16 * for microcontrollers - completely free of charge! *
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18 * >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
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20 * Thank you for using FreeRTOS, and thank you for your support! *
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22 ***************************************************************************
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25 This file is part of the FreeRTOS distribution.
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27 FreeRTOS is free software; you can redistribute it and/or modify it under
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28 the terms of the GNU General Public License (version 2) as published by the
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29 Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
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30 >>>NOTE<<< The modification to the GPL is included to allow you to
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31 distribute a combined work that includes FreeRTOS without being obliged to
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32 provide the source code for proprietary components outside of the FreeRTOS
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33 kernel. FreeRTOS is distributed in the hope that it will be useful, but
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34 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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35 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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36 more details. You should have received a copy of the GNU General Public
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37 License and the FreeRTOS license exception along with FreeRTOS; if not it
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38 can be viewed here: http://www.freertos.org/a00114.html and also obtained
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39 by writing to Richard Barry, contact details for whom are available on the
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44 http://www.FreeRTOS.org - Documentation, latest information, license and
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47 http://www.SafeRTOS.com - A version that is certified for use in safety
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50 http://www.OpenRTOS.com - Commercial support, development, porting,
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51 licensing and training services.
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54 /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
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55 all the API functions to use the MPU wrappers. That should only be done when
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56 task.h is included from an application file. */
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57 #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
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59 #include "FreeRTOS.h"
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64 #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE
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66 /* This entire source file will be skipped if the application is not configured
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67 to include software timer functionality. This #if is closed at the very bottom
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68 of this file. If you want to include software timer functionality then ensure
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69 configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
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70 #if ( configUSE_TIMERS == 1 )
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72 /* Misc definitions. */
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73 #define tmrNO_DELAY ( portTickType ) 0U
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75 /* The definition of the timers themselves. */
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76 typedef struct tmrTimerControl
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78 const signed char *pcTimerName; /*<< Text name. This is not used by the kernel, it is included simply to make debugging easier. */
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79 xListItem xTimerListItem; /*<< Standard linked list item as used by all kernel features for event management. */
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80 portTickType xTimerPeriodInTicks;/*<< How quickly and often the timer expires. */
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81 unsigned portBASE_TYPE uxAutoReload; /*<< Set to pdTRUE if the timer should be automatically restarted once expired. Set to pdFALSE if the timer is, in effect, a one shot timer. */
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82 void *pvTimerID; /*<< An ID to identify the timer. This allows the timer to be identified when the same callback is used for multiple timers. */
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83 tmrTIMER_CALLBACK pxCallbackFunction; /*<< The function that will be called when the timer expires. */
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86 /* The definition of messages that can be sent and received on the timer
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88 typedef struct tmrTimerQueueMessage
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90 portBASE_TYPE xMessageID; /*<< The command being sent to the timer service task. */
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91 portTickType xMessageValue; /*<< An optional value used by a subset of commands, for example, when changing the period of a timer. */
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92 xTIMER * pxTimer; /*<< The timer to which the command will be applied. */
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96 /* The list in which active timers are stored. Timers are referenced in expire
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97 time order, with the nearest expiry time at the front of the list. Only the
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98 timer service task is allowed to access xActiveTimerList. */
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99 PRIVILEGED_DATA static xList xActiveTimerList1;
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100 PRIVILEGED_DATA static xList xActiveTimerList2;
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101 PRIVILEGED_DATA static xList *pxCurrentTimerList;
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102 PRIVILEGED_DATA static xList *pxOverflowTimerList;
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104 /* A queue that is used to send commands to the timer service task. */
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105 PRIVILEGED_DATA static xQueueHandle xTimerQueue = NULL;
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107 #if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )
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109 PRIVILEGED_DATA static xTaskHandle xTimerTaskHandle = NULL;
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113 /*-----------------------------------------------------------*/
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116 * Initialise the infrastructure used by the timer service task if it has not
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117 * been initialised already.
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119 static void prvCheckForValidListAndQueue( void ) PRIVILEGED_FUNCTION;
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122 * The timer service task (daemon). Timer functionality is controlled by this
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123 * task. Other tasks communicate with the timer service task using the
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124 * xTimerQueue queue.
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126 static void prvTimerTask( void *pvParameters ) PRIVILEGED_FUNCTION;
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129 * Called by the timer service task to interpret and process a command it
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130 * received on the timer queue.
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132 static void prvProcessReceivedCommands( void ) PRIVILEGED_FUNCTION;
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135 * Insert the timer into either xActiveTimerList1, or xActiveTimerList2,
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136 * depending on if the expire time causes a timer counter overflow.
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138 static portBASE_TYPE prvInsertTimerInActiveList( xTIMER *pxTimer, portTickType xNextExpiryTime, portTickType xTimeNow, portTickType xCommandTime ) PRIVILEGED_FUNCTION;
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141 * An active timer has reached its expire time. Reload the timer if it is an
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142 * auto reload timer, then call its callback.
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144 static void prvProcessExpiredTimer( portTickType xNextExpireTime, portTickType xTimeNow ) PRIVILEGED_FUNCTION;
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147 * The tick count has overflowed. Switch the timer lists after ensuring the
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148 * current timer list does not still reference some timers.
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150 static void prvSwitchTimerLists( portTickType xLastTime ) PRIVILEGED_FUNCTION;
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153 * Obtain the current tick count, setting *pxTimerListsWereSwitched to pdTRUE
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154 * if a tick count overflow occurred since prvSampleTimeNow() was last called.
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156 static portTickType prvSampleTimeNow( portBASE_TYPE *pxTimerListsWereSwitched ) PRIVILEGED_FUNCTION;
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159 * If the timer list contains any active timers then return the expire time of
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160 * the timer that will expire first and set *pxListWasEmpty to false. If the
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161 * timer list does not contain any timers then return 0 and set *pxListWasEmpty
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164 static portTickType prvGetNextExpireTime( portBASE_TYPE *pxListWasEmpty ) PRIVILEGED_FUNCTION;
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167 * If a timer has expired, process it. Otherwise, block the timer service task
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168 * until either a timer does expire or a command is received.
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170 static void prvProcessTimerOrBlockTask( portTickType xNextExpireTime, portBASE_TYPE xListWasEmpty ) PRIVILEGED_FUNCTION;
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172 /*-----------------------------------------------------------*/
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174 portBASE_TYPE xTimerCreateTimerTask( void )
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176 portBASE_TYPE xReturn = pdFAIL;
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178 /* This function is called when the scheduler is started if
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179 configUSE_TIMERS is set to 1. Check that the infrastructure used by the
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180 timer service task has been created/initialised. If timers have already
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181 been created then the initialisation will already have been performed. */
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182 prvCheckForValidListAndQueue();
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184 if( xTimerQueue != NULL )
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186 #if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )
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188 /* Create the timer task, storing its handle in xTimerTaskHandle so
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189 it can be returned by the xTimerGetTimerDaemonTaskHandle() function. */
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190 xReturn = xTaskCreate( prvTimerTask, ( const signed char * ) "Tmr Svc", ( unsigned short ) configTIMER_TASK_STACK_DEPTH, NULL, ( unsigned portBASE_TYPE ) configTIMER_TASK_PRIORITY, &xTimerTaskHandle );
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194 /* Create the timer task without storing its handle. */
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195 xReturn = xTaskCreate( prvTimerTask, ( const signed char * ) "Tmr Svc", ( unsigned short ) configTIMER_TASK_STACK_DEPTH, NULL, ( unsigned portBASE_TYPE ) configTIMER_TASK_PRIORITY, NULL);
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200 configASSERT( xReturn );
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203 /*-----------------------------------------------------------*/
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205 xTimerHandle xTimerCreate( const signed char *pcTimerName, portTickType xTimerPeriodInTicks, unsigned portBASE_TYPE uxAutoReload, void *pvTimerID, tmrTIMER_CALLBACK pxCallbackFunction )
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207 xTIMER *pxNewTimer;
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209 /* Allocate the timer structure. */
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210 if( xTimerPeriodInTicks == ( portTickType ) 0U )
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213 configASSERT( ( xTimerPeriodInTicks > 0 ) );
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217 pxNewTimer = ( xTIMER * ) pvPortMalloc( sizeof( xTIMER ) );
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218 if( pxNewTimer != NULL )
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220 /* Ensure the infrastructure used by the timer service task has been
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221 created/initialised. */
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222 prvCheckForValidListAndQueue();
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224 /* Initialise the timer structure members using the function parameters. */
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225 pxNewTimer->pcTimerName = pcTimerName;
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226 pxNewTimer->xTimerPeriodInTicks = xTimerPeriodInTicks;
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227 pxNewTimer->uxAutoReload = uxAutoReload;
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228 pxNewTimer->pvTimerID = pvTimerID;
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229 pxNewTimer->pxCallbackFunction = pxCallbackFunction;
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230 vListInitialiseItem( &( pxNewTimer->xTimerListItem ) );
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232 traceTIMER_CREATE( pxNewTimer );
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236 traceTIMER_CREATE_FAILED();
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240 return ( xTimerHandle ) pxNewTimer;
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242 /*-----------------------------------------------------------*/
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244 portBASE_TYPE xTimerGenericCommand( xTimerHandle xTimer, portBASE_TYPE xCommandID, portTickType xOptionalValue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portTickType xBlockTime )
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246 portBASE_TYPE xReturn = pdFAIL;
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247 xTIMER_MESSAGE xMessage;
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249 /* Send a message to the timer service task to perform a particular action
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250 on a particular timer definition. */
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251 if( xTimerQueue != NULL )
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253 /* Send a command to the timer service task to start the xTimer timer. */
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254 xMessage.xMessageID = xCommandID;
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255 xMessage.xMessageValue = xOptionalValue;
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256 xMessage.pxTimer = ( xTIMER * ) xTimer;
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258 if( pxHigherPriorityTaskWoken == NULL )
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260 if( xTaskGetSchedulerState() == taskSCHEDULER_RUNNING )
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262 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, xBlockTime );
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266 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, tmrNO_DELAY );
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271 xReturn = xQueueSendToBackFromISR( xTimerQueue, &xMessage, pxHigherPriorityTaskWoken );
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274 traceTIMER_COMMAND_SEND( xTimer, xCommandID, xOptionalValue, xReturn );
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279 /*-----------------------------------------------------------*/
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281 #if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )
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283 xTaskHandle xTimerGetTimerDaemonTaskHandle( void )
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285 /* If xTimerGetTimerDaemonTaskHandle() is called before the scheduler has been
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286 started, then xTimerTaskHandle will be NULL. */
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287 configASSERT( ( xTimerTaskHandle != NULL ) );
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288 return xTimerTaskHandle;
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292 /*-----------------------------------------------------------*/
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294 static void prvProcessExpiredTimer( portTickType xNextExpireTime, portTickType xTimeNow )
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297 portBASE_TYPE xResult;
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299 /* Remove the timer from the list of active timers. A check has already
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300 been performed to ensure the list is not empty. */
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301 pxTimer = ( xTIMER * ) listGET_OWNER_OF_HEAD_ENTRY( pxCurrentTimerList );
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302 vListRemove( &( pxTimer->xTimerListItem ) );
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303 traceTIMER_EXPIRED( pxTimer );
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305 /* If the timer is an auto reload timer then calculate the next
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306 expiry time and re-insert the timer in the list of active timers. */
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307 if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )
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309 /* This is the only time a timer is inserted into a list using
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310 a time relative to anything other than the current time. It
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311 will therefore be inserted into the correct list relative to
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312 the time this task thinks it is now, even if a command to
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313 switch lists due to a tick count overflow is already waiting in
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314 the timer queue. */
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315 if( prvInsertTimerInActiveList( pxTimer, ( xNextExpireTime + pxTimer->xTimerPeriodInTicks ), xTimeNow, xNextExpireTime ) == pdTRUE )
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317 /* The timer expired before it was added to the active timer
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318 list. Reload it now. */
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319 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xNextExpireTime, NULL, tmrNO_DELAY );
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320 configASSERT( xResult );
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325 /* Call the timer callback. */
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326 pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );
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328 /*-----------------------------------------------------------*/
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330 static void prvTimerTask( void *pvParameters )
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332 portTickType xNextExpireTime;
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333 portBASE_TYPE xListWasEmpty;
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335 /* Just to avoid compiler warnings. */
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336 ( void ) pvParameters;
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340 /* Query the timers list to see if it contains any timers, and if so,
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341 obtain the time at which the next timer will expire. */
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342 xNextExpireTime = prvGetNextExpireTime( &xListWasEmpty );
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344 /* If a timer has expired, process it. Otherwise, block this task
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345 until either a timer does expire, or a command is received. */
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346 prvProcessTimerOrBlockTask( xNextExpireTime, xListWasEmpty );
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348 /* Empty the command queue. */
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349 prvProcessReceivedCommands();
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352 /*-----------------------------------------------------------*/
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354 static void prvProcessTimerOrBlockTask( portTickType xNextExpireTime, portBASE_TYPE xListWasEmpty )
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356 portTickType xTimeNow;
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357 portBASE_TYPE xTimerListsWereSwitched;
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361 /* Obtain the time now to make an assessment as to whether the timer
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362 has expired or not. If obtaining the time causes the lists to switch
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363 then don't process this timer as any timers that remained in the list
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364 when the lists were switched will have been processed within the
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365 prvSampelTimeNow() function. */
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366 xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
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367 if( xTimerListsWereSwitched == pdFALSE )
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369 /* The tick count has not overflowed, has the timer expired? */
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370 if( ( xListWasEmpty == pdFALSE ) && ( xNextExpireTime <= xTimeNow ) )
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373 prvProcessExpiredTimer( xNextExpireTime, xTimeNow );
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377 /* The tick count has not overflowed, and the next expire
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378 time has not been reached yet. This task should therefore
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379 block to wait for the next expire time or a command to be
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380 received - whichever comes first. The following line cannot
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381 be reached unless xNextExpireTime > xTimeNow, except in the
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382 case when the current timer list is empty. */
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383 vQueueWaitForMessageRestricted( xTimerQueue, ( xNextExpireTime - xTimeNow ) );
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385 if( xTaskResumeAll() == pdFALSE )
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387 /* Yield to wait for either a command to arrive, or the block time
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388 to expire. If a command arrived between the critical section being
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389 exited and this yield then the yield will not cause the task
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391 portYIELD_WITHIN_API();
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401 /*-----------------------------------------------------------*/
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403 static portTickType prvGetNextExpireTime( portBASE_TYPE *pxListWasEmpty )
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405 portTickType xNextExpireTime;
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407 /* Timers are listed in expiry time order, with the head of the list
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408 referencing the task that will expire first. Obtain the time at which
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409 the timer with the nearest expiry time will expire. If there are no
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410 active timers then just set the next expire time to 0. That will cause
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411 this task to unblock when the tick count overflows, at which point the
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412 timer lists will be switched and the next expiry time can be
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414 *pxListWasEmpty = listLIST_IS_EMPTY( pxCurrentTimerList );
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415 if( *pxListWasEmpty == pdFALSE )
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417 xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
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421 /* Ensure the task unblocks when the tick count rolls over. */
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422 xNextExpireTime = ( portTickType ) 0U;
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425 return xNextExpireTime;
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427 /*-----------------------------------------------------------*/
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429 static portTickType prvSampleTimeNow( portBASE_TYPE *pxTimerListsWereSwitched )
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431 portTickType xTimeNow;
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432 static portTickType xLastTime = ( portTickType ) 0U;
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434 xTimeNow = xTaskGetTickCount();
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436 if( xTimeNow < xLastTime )
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438 prvSwitchTimerLists( xLastTime );
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439 *pxTimerListsWereSwitched = pdTRUE;
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443 *pxTimerListsWereSwitched = pdFALSE;
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446 xLastTime = xTimeNow;
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450 /*-----------------------------------------------------------*/
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452 static portBASE_TYPE prvInsertTimerInActiveList( xTIMER *pxTimer, portTickType xNextExpiryTime, portTickType xTimeNow, portTickType xCommandTime )
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454 portBASE_TYPE xProcessTimerNow = pdFALSE;
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456 listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xNextExpiryTime );
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457 listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );
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459 if( xNextExpiryTime <= xTimeNow )
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461 /* Has the expiry time elapsed between the command to start/reset a
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462 timer was issued, and the time the command was processed? */
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463 if( ( ( portTickType ) ( xTimeNow - xCommandTime ) ) >= pxTimer->xTimerPeriodInTicks )
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465 /* The time between a command being issued and the command being
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466 processed actually exceeds the timers period. */
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467 xProcessTimerNow = pdTRUE;
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471 vListInsert( pxOverflowTimerList, &( pxTimer->xTimerListItem ) );
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476 if( ( xTimeNow < xCommandTime ) && ( xNextExpiryTime >= xCommandTime ) )
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478 /* If, since the command was issued, the tick count has overflowed
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479 but the expiry time has not, then the timer must have already passed
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480 its expiry time and should be processed immediately. */
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481 xProcessTimerNow = pdTRUE;
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485 vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );
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489 return xProcessTimerNow;
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491 /*-----------------------------------------------------------*/
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493 static void prvProcessReceivedCommands( void )
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495 xTIMER_MESSAGE xMessage;
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497 portBASE_TYPE xTimerListsWereSwitched, xResult;
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498 portTickType xTimeNow;
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500 /* In this case the xTimerListsWereSwitched parameter is not used, but it
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501 must be present in the function call. */
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502 xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
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504 while( xQueueReceive( xTimerQueue, &xMessage, tmrNO_DELAY ) != pdFAIL )
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506 pxTimer = xMessage.pxTimer;
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508 /* Is the timer already in a list of active timers? When the command
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509 is trmCOMMAND_PROCESS_TIMER_OVERFLOW, the timer will be NULL as the
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510 command is to the task rather than to an individual timer. */
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511 if( pxTimer != NULL )
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513 if( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) == pdFALSE )
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515 /* The timer is in a list, remove it. */
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516 vListRemove( &( pxTimer->xTimerListItem ) );
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520 traceTIMER_COMMAND_RECEIVED( pxTimer, xMessage.xMessageID, xMessage.xMessageValue );
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522 switch( xMessage.xMessageID )
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524 case tmrCOMMAND_START :
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525 /* Start or restart a timer. */
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526 if( prvInsertTimerInActiveList( pxTimer, xMessage.xMessageValue + pxTimer->xTimerPeriodInTicks, xTimeNow, xMessage.xMessageValue ) == pdTRUE )
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528 /* The timer expired before it was added to the active timer
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529 list. Process it now. */
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530 pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );
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532 if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )
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534 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xMessage.xMessageValue + pxTimer->xTimerPeriodInTicks, NULL, tmrNO_DELAY );
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535 configASSERT( xResult );
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541 case tmrCOMMAND_STOP :
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542 /* The timer has already been removed from the active list.
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543 There is nothing to do here. */
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546 case tmrCOMMAND_CHANGE_PERIOD :
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547 pxTimer->xTimerPeriodInTicks = xMessage.xMessageValue;
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548 configASSERT( ( pxTimer->xTimerPeriodInTicks > 0 ) );
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549 prvInsertTimerInActiveList( pxTimer, ( xTimeNow + pxTimer->xTimerPeriodInTicks ), xTimeNow, xTimeNow );
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552 case tmrCOMMAND_DELETE :
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553 /* The timer has already been removed from the active list,
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554 just free up the memory. */
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555 vPortFree( pxTimer );
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559 /* Don't expect to get here. */
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564 /*-----------------------------------------------------------*/
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566 static void prvSwitchTimerLists( portTickType xLastTime )
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568 portTickType xNextExpireTime, xReloadTime;
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571 portBASE_TYPE xResult;
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573 /* Remove compiler warnings if configASSERT() is not defined. */
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574 ( void ) xLastTime;
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576 /* The tick count has overflowed. The timer lists must be switched.
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577 If there are any timers still referenced from the current timer list
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578 then they must have expired and should be processed before the lists
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580 while( listLIST_IS_EMPTY( pxCurrentTimerList ) == pdFALSE )
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582 xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
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584 /* Remove the timer from the list. */
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585 pxTimer = ( xTIMER * ) listGET_OWNER_OF_HEAD_ENTRY( pxCurrentTimerList );
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586 vListRemove( &( pxTimer->xTimerListItem ) );
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588 /* Execute its callback, then send a command to restart the timer if
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589 it is an auto-reload timer. It cannot be restarted here as the lists
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590 have not yet been switched. */
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591 pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );
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593 if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )
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595 /* Calculate the reload value, and if the reload value results in
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596 the timer going into the same timer list then it has already expired
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597 and the timer should be re-inserted into the current list so it is
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598 processed again within this loop. Otherwise a command should be sent
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599 to restart the timer to ensure it is only inserted into a list after
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600 the lists have been swapped. */
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601 xReloadTime = ( xNextExpireTime + pxTimer->xTimerPeriodInTicks );
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602 if( xReloadTime > xNextExpireTime )
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604 listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xReloadTime );
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605 listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );
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606 vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );
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610 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xNextExpireTime, NULL, tmrNO_DELAY );
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611 configASSERT( xResult );
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617 pxTemp = pxCurrentTimerList;
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618 pxCurrentTimerList = pxOverflowTimerList;
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619 pxOverflowTimerList = pxTemp;
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621 /*-----------------------------------------------------------*/
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623 static void prvCheckForValidListAndQueue( void )
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625 /* Check that the list from which active timers are referenced, and the
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626 queue used to communicate with the timer service, have been
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628 taskENTER_CRITICAL();
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630 if( xTimerQueue == NULL )
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632 vListInitialise( &xActiveTimerList1 );
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633 vListInitialise( &xActiveTimerList2 );
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634 pxCurrentTimerList = &xActiveTimerList1;
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635 pxOverflowTimerList = &xActiveTimerList2;
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636 xTimerQueue = xQueueCreate( ( unsigned portBASE_TYPE ) configTIMER_QUEUE_LENGTH, sizeof( xTIMER_MESSAGE ) );
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639 taskEXIT_CRITICAL();
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641 /*-----------------------------------------------------------*/
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643 portBASE_TYPE xTimerIsTimerActive( xTimerHandle xTimer )
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645 portBASE_TYPE xTimerIsInActiveList;
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646 xTIMER *pxTimer = ( xTIMER * ) xTimer;
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648 /* Is the timer in the list of active timers? */
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649 taskENTER_CRITICAL();
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651 /* Checking to see if it is in the NULL list in effect checks to see if
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652 it is referenced from either the current or the overflow timer lists in
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653 one go, but the logic has to be reversed, hence the '!'. */
\r
654 xTimerIsInActiveList = !( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) );
\r
656 taskEXIT_CRITICAL();
\r
658 return xTimerIsInActiveList;
\r
660 /*-----------------------------------------------------------*/
\r
662 void *pvTimerGetTimerID( xTimerHandle xTimer )
\r
664 xTIMER *pxTimer = ( xTIMER * ) xTimer;
\r
666 return pxTimer->pvTimerID;
\r
668 /*-----------------------------------------------------------*/
\r
670 /* This entire source file will be skipped if the application is not configured
\r
671 to include software timer functionality. If you want to include software timer
\r
672 functionality then ensure configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
\r
673 #endif /* configUSE_TIMERS == 1 */
\r