2 FreeRTOS V7.4.2 - Copyright (C) 2013 Real Time Engineers Ltd.
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4 FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME. PLEASE VISIT
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5 http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
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7 ***************************************************************************
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9 * FreeRTOS tutorial books are available in pdf and paperback. *
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10 * Complete, revised, and edited pdf reference manuals are also *
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13 * Purchasing FreeRTOS documentation will not only help you, by *
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14 * ensuring you get running as quickly as possible and with an *
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15 * in-depth knowledge of how to use FreeRTOS, it will also help *
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16 * the FreeRTOS project to continue with its mission of providing *
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17 * professional grade, cross platform, de facto standard solutions *
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18 * for microcontrollers - completely free of charge! *
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20 * >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
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22 * Thank you for using FreeRTOS, and thank you for your support! *
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24 ***************************************************************************
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27 This file is part of the FreeRTOS distribution.
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29 FreeRTOS is free software; you can redistribute it and/or modify it under
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30 the terms of the GNU General Public License (version 2) as published by the
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31 Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
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33 >>>>>>NOTE<<<<<< The modification to the GPL is included to allow you to
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34 distribute a combined work that includes FreeRTOS without being obliged to
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35 provide the source code for proprietary components outside of the FreeRTOS
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38 FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
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39 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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40 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
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41 details. You should have received a copy of the GNU General Public License
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42 and the FreeRTOS license exception along with FreeRTOS; if not it can be
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43 viewed here: http://www.freertos.org/a00114.html and also obtained by
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44 writing to Real Time Engineers Ltd., contact details for whom are available
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45 on the FreeRTOS WEB site.
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49 ***************************************************************************
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51 * Having a problem? Start by reading the FAQ "My application does *
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52 * not run, what could be wrong?" *
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54 * http://www.FreeRTOS.org/FAQHelp.html *
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56 ***************************************************************************
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59 http://www.FreeRTOS.org - Documentation, books, training, latest versions,
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60 license and Real Time Engineers Ltd. contact details.
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62 http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
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63 including FreeRTOS+Trace - an indispensable productivity tool, and our new
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64 fully thread aware and reentrant UDP/IP stack.
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66 http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
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67 Integrity Systems, who sell the code with commercial support,
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68 indemnification and middleware, under the OpenRTOS brand.
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70 http://www.SafeRTOS.com - High Integrity Systems also provide a safety
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71 engineered and independently SIL3 certified version for use in safety and
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72 mission critical applications that require provable dependability.
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75 /* Standard includes. */
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78 /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
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79 all the API functions to use the MPU wrappers. That should only be done when
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80 task.h is included from an application file. */
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81 #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
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83 #include "FreeRTOS.h"
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88 /* Lint e961 and e750 are suppressed as a MISRA exception justified because the
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89 MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined for the
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90 header files above, but not in this file, in order to generate the correct
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91 privileged Vs unprivileged linkage and placement. */
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92 #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e961 !e750. */
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95 /* This entire source file will be skipped if the application is not configured
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96 to include software timer functionality. This #if is closed at the very bottom
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97 of this file. If you want to include software timer functionality then ensure
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98 configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
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99 #if ( configUSE_TIMERS == 1 )
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101 /* Misc definitions. */
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102 #define tmrNO_DELAY ( portTickType ) 0U
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104 /* The definition of the timers themselves. */
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105 typedef struct tmrTimerControl
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107 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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108 xListItem xTimerListItem; /*<< Standard linked list item as used by all kernel features for event management. */
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109 portTickType xTimerPeriodInTicks;/*<< How quickly and often the timer expires. */
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110 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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111 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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112 tmrTIMER_CALLBACK pxCallbackFunction; /*<< The function that will be called when the timer expires. */
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115 /* The definition of messages that can be sent and received on the timer
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117 typedef struct tmrTimerQueueMessage
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119 portBASE_TYPE xMessageID; /*<< The command being sent to the timer service task. */
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120 portTickType xMessageValue; /*<< An optional value used by a subset of commands, for example, when changing the period of a timer. */
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121 xTIMER * pxTimer; /*<< The timer to which the command will be applied. */
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124 /*lint -e956 A manual analysis and inspection has been used to determine which
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125 static variables must be declared volatile. */
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127 /* The list in which active timers are stored. Timers are referenced in expire
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128 time order, with the nearest expiry time at the front of the list. Only the
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129 timer service task is allowed to access xActiveTimerList. */
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130 PRIVILEGED_DATA static xList xActiveTimerList1;
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131 PRIVILEGED_DATA static xList xActiveTimerList2;
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132 PRIVILEGED_DATA static xList *pxCurrentTimerList;
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133 PRIVILEGED_DATA static xList *pxOverflowTimerList;
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135 /* A queue that is used to send commands to the timer service task. */
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136 PRIVILEGED_DATA static xQueueHandle xTimerQueue = NULL;
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138 #if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )
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140 PRIVILEGED_DATA static xTaskHandle xTimerTaskHandle = NULL;
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146 /*-----------------------------------------------------------*/
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149 * Initialise the infrastructure used by the timer service task if it has not
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150 * been initialised already.
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152 static void prvCheckForValidListAndQueue( void ) PRIVILEGED_FUNCTION;
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155 * The timer service task (daemon). Timer functionality is controlled by this
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156 * task. Other tasks communicate with the timer service task using the
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157 * xTimerQueue queue.
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159 static void prvTimerTask( void *pvParameters ) PRIVILEGED_FUNCTION;
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162 * Called by the timer service task to interpret and process a command it
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163 * received on the timer queue.
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165 static void prvProcessReceivedCommands( void ) PRIVILEGED_FUNCTION;
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168 * Insert the timer into either xActiveTimerList1, or xActiveTimerList2,
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169 * depending on if the expire time causes a timer counter overflow.
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171 static portBASE_TYPE prvInsertTimerInActiveList( xTIMER *pxTimer, portTickType xNextExpiryTime, portTickType xTimeNow, portTickType xCommandTime ) PRIVILEGED_FUNCTION;
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174 * An active timer has reached its expire time. Reload the timer if it is an
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175 * auto reload timer, then call its callback.
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177 static void prvProcessExpiredTimer( portTickType xNextExpireTime, portTickType xTimeNow ) PRIVILEGED_FUNCTION;
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180 * The tick count has overflowed. Switch the timer lists after ensuring the
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181 * current timer list does not still reference some timers.
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183 static void prvSwitchTimerLists( portTickType xLastTime ) PRIVILEGED_FUNCTION;
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186 * Obtain the current tick count, setting *pxTimerListsWereSwitched to pdTRUE
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187 * if a tick count overflow occurred since prvSampleTimeNow() was last called.
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189 static portTickType prvSampleTimeNow( portBASE_TYPE *pxTimerListsWereSwitched ) PRIVILEGED_FUNCTION;
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192 * If the timer list contains any active timers then return the expire time of
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193 * the timer that will expire first and set *pxListWasEmpty to false. If the
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194 * timer list does not contain any timers then return 0 and set *pxListWasEmpty
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197 static portTickType prvGetNextExpireTime( portBASE_TYPE *pxListWasEmpty ) PRIVILEGED_FUNCTION;
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200 * If a timer has expired, process it. Otherwise, block the timer service task
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201 * until either a timer does expire or a command is received.
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203 static void prvProcessTimerOrBlockTask( portTickType xNextExpireTime, portBASE_TYPE xListWasEmpty ) PRIVILEGED_FUNCTION;
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205 /*-----------------------------------------------------------*/
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207 portBASE_TYPE xTimerCreateTimerTask( void )
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209 portBASE_TYPE xReturn = pdFAIL;
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211 /* This function is called when the scheduler is started if
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212 configUSE_TIMERS is set to 1. Check that the infrastructure used by the
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213 timer service task has been created/initialised. If timers have already
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214 been created then the initialisation will already have been performed. */
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215 prvCheckForValidListAndQueue();
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217 if( xTimerQueue != NULL )
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219 #if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )
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221 /* Create the timer task, storing its handle in xTimerTaskHandle so
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222 it can be returned by the xTimerGetTimerDaemonTaskHandle() function. */
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223 xReturn = xTaskCreate( prvTimerTask, ( const signed char * ) "Tmr Svc", ( unsigned short ) configTIMER_TASK_STACK_DEPTH, NULL, ( ( unsigned portBASE_TYPE ) configTIMER_TASK_PRIORITY ) | portPRIVILEGE_BIT, &xTimerTaskHandle );
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227 /* Create the timer task without storing its handle. */
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228 xReturn = xTaskCreate( prvTimerTask, ( const signed char * ) "Tmr Svc", ( unsigned short ) configTIMER_TASK_STACK_DEPTH, NULL, ( ( unsigned portBASE_TYPE ) configTIMER_TASK_PRIORITY ) | portPRIVILEGE_BIT, NULL);
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233 configASSERT( xReturn );
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236 /*-----------------------------------------------------------*/
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238 xTimerHandle xTimerCreate( const signed char * const pcTimerName, portTickType xTimerPeriodInTicks, unsigned portBASE_TYPE uxAutoReload, void *pvTimerID, tmrTIMER_CALLBACK pxCallbackFunction )
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240 xTIMER *pxNewTimer;
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242 /* Allocate the timer structure. */
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243 if( xTimerPeriodInTicks == ( portTickType ) 0U )
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246 configASSERT( ( xTimerPeriodInTicks > 0 ) );
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250 pxNewTimer = ( xTIMER * ) pvPortMalloc( sizeof( xTIMER ) );
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251 if( pxNewTimer != NULL )
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253 /* Ensure the infrastructure used by the timer service task has been
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254 created/initialised. */
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255 prvCheckForValidListAndQueue();
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257 /* Initialise the timer structure members using the function parameters. */
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258 pxNewTimer->pcTimerName = pcTimerName;
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259 pxNewTimer->xTimerPeriodInTicks = xTimerPeriodInTicks;
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260 pxNewTimer->uxAutoReload = uxAutoReload;
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261 pxNewTimer->pvTimerID = pvTimerID;
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262 pxNewTimer->pxCallbackFunction = pxCallbackFunction;
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263 vListInitialiseItem( &( pxNewTimer->xTimerListItem ) );
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265 traceTIMER_CREATE( pxNewTimer );
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269 traceTIMER_CREATE_FAILED();
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273 return ( xTimerHandle ) pxNewTimer;
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275 /*-----------------------------------------------------------*/
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277 portBASE_TYPE xTimerGenericCommand( xTimerHandle xTimer, portBASE_TYPE xCommandID, portTickType xOptionalValue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portTickType xBlockTime )
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279 portBASE_TYPE xReturn = pdFAIL;
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280 xTIMER_MESSAGE xMessage;
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282 /* Send a message to the timer service task to perform a particular action
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283 on a particular timer definition. */
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284 if( xTimerQueue != NULL )
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286 /* Send a command to the timer service task to start the xTimer timer. */
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287 xMessage.xMessageID = xCommandID;
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288 xMessage.xMessageValue = xOptionalValue;
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289 xMessage.pxTimer = ( xTIMER * ) xTimer;
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291 if( pxHigherPriorityTaskWoken == NULL )
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293 if( xTaskGetSchedulerState() == taskSCHEDULER_RUNNING )
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295 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, xBlockTime );
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299 xReturn = xQueueSendToBack( xTimerQueue, &xMessage, tmrNO_DELAY );
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304 xReturn = xQueueSendToBackFromISR( xTimerQueue, &xMessage, pxHigherPriorityTaskWoken );
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307 traceTIMER_COMMAND_SEND( xTimer, xCommandID, xOptionalValue, xReturn );
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312 /*-----------------------------------------------------------*/
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314 #if ( INCLUDE_xTimerGetTimerDaemonTaskHandle == 1 )
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316 xTaskHandle xTimerGetTimerDaemonTaskHandle( void )
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318 /* If xTimerGetTimerDaemonTaskHandle() is called before the scheduler has been
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319 started, then xTimerTaskHandle will be NULL. */
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320 configASSERT( ( xTimerTaskHandle != NULL ) );
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321 return xTimerTaskHandle;
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325 /*-----------------------------------------------------------*/
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327 static void prvProcessExpiredTimer( portTickType xNextExpireTime, portTickType xTimeNow )
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330 portBASE_TYPE xResult;
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332 /* Remove the timer from the list of active timers. A check has already
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333 been performed to ensure the list is not empty. */
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334 pxTimer = ( xTIMER * ) listGET_OWNER_OF_HEAD_ENTRY( pxCurrentTimerList );
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335 ( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
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336 traceTIMER_EXPIRED( pxTimer );
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338 /* If the timer is an auto reload timer then calculate the next
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339 expiry time and re-insert the timer in the list of active timers. */
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340 if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )
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342 /* This is the only time a timer is inserted into a list using
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343 a time relative to anything other than the current time. It
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344 will therefore be inserted into the correct list relative to
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345 the time this task thinks it is now, even if a command to
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346 switch lists due to a tick count overflow is already waiting in
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347 the timer queue. */
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348 if( prvInsertTimerInActiveList( pxTimer, ( xNextExpireTime + pxTimer->xTimerPeriodInTicks ), xTimeNow, xNextExpireTime ) == pdTRUE )
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350 /* The timer expired before it was added to the active timer
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351 list. Reload it now. */
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352 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xNextExpireTime, NULL, tmrNO_DELAY );
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353 configASSERT( xResult );
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358 /* Call the timer callback. */
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359 pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );
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361 /*-----------------------------------------------------------*/
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363 static void prvTimerTask( void *pvParameters )
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365 portTickType xNextExpireTime;
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366 portBASE_TYPE xListWasEmpty;
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368 /* Just to avoid compiler warnings. */
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369 ( void ) pvParameters;
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373 /* Query the timers list to see if it contains any timers, and if so,
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374 obtain the time at which the next timer will expire. */
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375 xNextExpireTime = prvGetNextExpireTime( &xListWasEmpty );
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377 /* If a timer has expired, process it. Otherwise, block this task
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378 until either a timer does expire, or a command is received. */
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379 prvProcessTimerOrBlockTask( xNextExpireTime, xListWasEmpty );
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381 /* Empty the command queue. */
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382 prvProcessReceivedCommands();
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385 /*-----------------------------------------------------------*/
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387 static void prvProcessTimerOrBlockTask( portTickType xNextExpireTime, portBASE_TYPE xListWasEmpty )
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389 portTickType xTimeNow;
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390 portBASE_TYPE xTimerListsWereSwitched;
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394 /* Obtain the time now to make an assessment as to whether the timer
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395 has expired or not. If obtaining the time causes the lists to switch
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396 then don't process this timer as any timers that remained in the list
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397 when the lists were switched will have been processed within the
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398 prvSampelTimeNow() function. */
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399 xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
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400 if( xTimerListsWereSwitched == pdFALSE )
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402 /* The tick count has not overflowed, has the timer expired? */
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403 if( ( xListWasEmpty == pdFALSE ) && ( xNextExpireTime <= xTimeNow ) )
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405 ( void ) xTaskResumeAll();
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406 prvProcessExpiredTimer( xNextExpireTime, xTimeNow );
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410 /* The tick count has not overflowed, and the next expire
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411 time has not been reached yet. This task should therefore
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412 block to wait for the next expire time or a command to be
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413 received - whichever comes first. The following line cannot
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414 be reached unless xNextExpireTime > xTimeNow, except in the
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415 case when the current timer list is empty. */
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416 vQueueWaitForMessageRestricted( xTimerQueue, ( xNextExpireTime - xTimeNow ) );
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418 if( xTaskResumeAll() == pdFALSE )
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420 /* Yield to wait for either a command to arrive, or the block time
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421 to expire. If a command arrived between the critical section being
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422 exited and this yield then the yield will not cause the task
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424 portYIELD_WITHIN_API();
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430 ( void ) xTaskResumeAll();
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434 /*-----------------------------------------------------------*/
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436 static portTickType prvGetNextExpireTime( portBASE_TYPE *pxListWasEmpty )
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438 portTickType xNextExpireTime;
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440 /* Timers are listed in expiry time order, with the head of the list
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441 referencing the task that will expire first. Obtain the time at which
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442 the timer with the nearest expiry time will expire. If there are no
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443 active timers then just set the next expire time to 0. That will cause
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444 this task to unblock when the tick count overflows, at which point the
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445 timer lists will be switched and the next expiry time can be
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447 *pxListWasEmpty = listLIST_IS_EMPTY( pxCurrentTimerList );
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448 if( *pxListWasEmpty == pdFALSE )
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450 xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
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454 /* Ensure the task unblocks when the tick count rolls over. */
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455 xNextExpireTime = ( portTickType ) 0U;
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458 return xNextExpireTime;
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460 /*-----------------------------------------------------------*/
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462 static portTickType prvSampleTimeNow( portBASE_TYPE *pxTimerListsWereSwitched )
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464 portTickType xTimeNow;
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465 PRIVILEGED_DATA static portTickType xLastTime = ( portTickType ) 0U; /*lint !e956 Variable is only accessible to one task. */
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467 xTimeNow = xTaskGetTickCount();
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469 if( xTimeNow < xLastTime )
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471 prvSwitchTimerLists( xLastTime );
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472 *pxTimerListsWereSwitched = pdTRUE;
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476 *pxTimerListsWereSwitched = pdFALSE;
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479 xLastTime = xTimeNow;
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483 /*-----------------------------------------------------------*/
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485 static portBASE_TYPE prvInsertTimerInActiveList( xTIMER *pxTimer, portTickType xNextExpiryTime, portTickType xTimeNow, portTickType xCommandTime )
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487 portBASE_TYPE xProcessTimerNow = pdFALSE;
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489 listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xNextExpiryTime );
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490 listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );
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492 if( xNextExpiryTime <= xTimeNow )
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494 /* Has the expiry time elapsed between the command to start/reset a
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495 timer was issued, and the time the command was processed? */
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496 if( ( xTimeNow - xCommandTime ) >= pxTimer->xTimerPeriodInTicks )
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498 /* The time between a command being issued and the command being
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499 processed actually exceeds the timers period. */
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500 xProcessTimerNow = pdTRUE;
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504 vListInsert( pxOverflowTimerList, &( pxTimer->xTimerListItem ) );
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509 if( ( xTimeNow < xCommandTime ) && ( xNextExpiryTime >= xCommandTime ) )
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511 /* If, since the command was issued, the tick count has overflowed
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512 but the expiry time has not, then the timer must have already passed
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513 its expiry time and should be processed immediately. */
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514 xProcessTimerNow = pdTRUE;
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518 vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );
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522 return xProcessTimerNow;
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524 /*-----------------------------------------------------------*/
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526 static void prvProcessReceivedCommands( void )
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528 xTIMER_MESSAGE xMessage;
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530 portBASE_TYPE xTimerListsWereSwitched, xResult;
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531 portTickType xTimeNow;
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533 while( xQueueReceive( xTimerQueue, &xMessage, tmrNO_DELAY ) != pdFAIL ) /*lint !e603 xMessage does not have to be initialised as it is passed out, not in, and it is not used unless xQueueReceive() returns pdTRUE. */
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535 pxTimer = xMessage.pxTimer;
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537 if( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) == pdFALSE )
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539 /* The timer is in a list, remove it. */
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540 ( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
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543 traceTIMER_COMMAND_RECEIVED( pxTimer, xMessage.xMessageID, xMessage.xMessageValue );
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545 /* In this case the xTimerListsWereSwitched parameter is not used, but
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546 it must be present in the function call. prvSampleTimeNow() must be
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547 called after the message is received from xTimerQueue so there is no
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548 possibility of a higher priority task adding a message to the message
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549 queue with a time that is ahead of the timer daemon task (because it
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550 pre-empted the timer daemon task after the xTimeNow value was set). */
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551 xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
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553 switch( xMessage.xMessageID )
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555 case tmrCOMMAND_START :
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556 /* Start or restart a timer. */
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557 if( prvInsertTimerInActiveList( pxTimer, xMessage.xMessageValue + pxTimer->xTimerPeriodInTicks, xTimeNow, xMessage.xMessageValue ) == pdTRUE )
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559 /* The timer expired before it was added to the active timer
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560 list. Process it now. */
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561 pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );
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563 if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )
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565 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xMessage.xMessageValue + pxTimer->xTimerPeriodInTicks, NULL, tmrNO_DELAY );
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566 configASSERT( xResult );
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572 case tmrCOMMAND_STOP :
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573 /* The timer has already been removed from the active list.
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574 There is nothing to do here. */
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577 case tmrCOMMAND_CHANGE_PERIOD :
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578 pxTimer->xTimerPeriodInTicks = xMessage.xMessageValue;
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579 configASSERT( ( pxTimer->xTimerPeriodInTicks > 0 ) );
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580 ( void ) prvInsertTimerInActiveList( pxTimer, ( xTimeNow + pxTimer->xTimerPeriodInTicks ), xTimeNow, xTimeNow );
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583 case tmrCOMMAND_DELETE :
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584 /* The timer has already been removed from the active list,
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585 just free up the memory. */
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586 vPortFree( pxTimer );
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590 /* Don't expect to get here. */
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595 /*-----------------------------------------------------------*/
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597 static void prvSwitchTimerLists( portTickType xLastTime )
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599 portTickType xNextExpireTime, xReloadTime;
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602 portBASE_TYPE xResult;
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604 /* Remove compiler warnings if configASSERT() is not defined. */
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605 ( void ) xLastTime;
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607 /* The tick count has overflowed. The timer lists must be switched.
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608 If there are any timers still referenced from the current timer list
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609 then they must have expired and should be processed before the lists
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611 while( listLIST_IS_EMPTY( pxCurrentTimerList ) == pdFALSE )
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613 xNextExpireTime = listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxCurrentTimerList );
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615 /* Remove the timer from the list. */
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616 pxTimer = ( xTIMER * ) listGET_OWNER_OF_HEAD_ENTRY( pxCurrentTimerList );
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617 ( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
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619 /* Execute its callback, then send a command to restart the timer if
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620 it is an auto-reload timer. It cannot be restarted here as the lists
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621 have not yet been switched. */
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622 pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );
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624 if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )
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626 /* Calculate the reload value, and if the reload value results in
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627 the timer going into the same timer list then it has already expired
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628 and the timer should be re-inserted into the current list so it is
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629 processed again within this loop. Otherwise a command should be sent
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630 to restart the timer to ensure it is only inserted into a list after
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631 the lists have been swapped. */
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632 xReloadTime = ( xNextExpireTime + pxTimer->xTimerPeriodInTicks );
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633 if( xReloadTime > xNextExpireTime )
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635 listSET_LIST_ITEM_VALUE( &( pxTimer->xTimerListItem ), xReloadTime );
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636 listSET_LIST_ITEM_OWNER( &( pxTimer->xTimerListItem ), pxTimer );
\r
637 vListInsert( pxCurrentTimerList, &( pxTimer->xTimerListItem ) );
\r
641 xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xNextExpireTime, NULL, tmrNO_DELAY );
\r
642 configASSERT( xResult );
\r
648 pxTemp = pxCurrentTimerList;
\r
649 pxCurrentTimerList = pxOverflowTimerList;
\r
650 pxOverflowTimerList = pxTemp;
\r
652 /*-----------------------------------------------------------*/
\r
654 static void prvCheckForValidListAndQueue( void )
\r
656 /* Check that the list from which active timers are referenced, and the
\r
657 queue used to communicate with the timer service, have been
\r
659 taskENTER_CRITICAL();
\r
661 if( xTimerQueue == NULL )
\r
663 vListInitialise( &xActiveTimerList1 );
\r
664 vListInitialise( &xActiveTimerList2 );
\r
665 pxCurrentTimerList = &xActiveTimerList1;
\r
666 pxOverflowTimerList = &xActiveTimerList2;
\r
667 xTimerQueue = xQueueCreate( ( unsigned portBASE_TYPE ) configTIMER_QUEUE_LENGTH, sizeof( xTIMER_MESSAGE ) );
\r
670 taskEXIT_CRITICAL();
\r
672 /*-----------------------------------------------------------*/
\r
674 portBASE_TYPE xTimerIsTimerActive( xTimerHandle xTimer )
\r
676 portBASE_TYPE xTimerIsInActiveList;
\r
677 xTIMER *pxTimer = ( xTIMER * ) xTimer;
\r
679 /* Is the timer in the list of active timers? */
\r
680 taskENTER_CRITICAL();
\r
682 /* Checking to see if it is in the NULL list in effect checks to see if
\r
683 it is referenced from either the current or the overflow timer lists in
\r
684 one go, but the logic has to be reversed, hence the '!'. */
\r
685 xTimerIsInActiveList = !( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) );
\r
687 taskEXIT_CRITICAL();
\r
689 return xTimerIsInActiveList;
\r
691 /*-----------------------------------------------------------*/
\r
693 void *pvTimerGetTimerID( xTimerHandle xTimer )
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695 xTIMER *pxTimer = ( xTIMER * ) xTimer;
\r
697 return pxTimer->pvTimerID;
\r
699 /*-----------------------------------------------------------*/
\r
701 /* This entire source file will be skipped if the application is not configured
\r
702 to include software timer functionality. If you want to include software timer
\r
703 functionality then ensure configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
\r
704 #endif /* configUSE_TIMERS == 1 */
\r