2 FreeRTOS V8.1.2 - Copyright (C) 2014 Real Time Engineers Ltd.
\r
5 VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
\r
7 ***************************************************************************
\r
9 * FreeRTOS provides completely free yet professionally developed, *
\r
10 * robust, strictly quality controlled, supported, and cross *
\r
11 * platform software that has become a de facto standard. *
\r
13 * Help yourself get started quickly and support the FreeRTOS *
\r
14 * project by purchasing a FreeRTOS tutorial book, reference *
\r
15 * manual, or both from: http://www.FreeRTOS.org/Documentation *
\r
19 ***************************************************************************
\r
21 This file is part of the FreeRTOS distribution.
\r
23 FreeRTOS is free software; you can redistribute it and/or modify it under
\r
24 the terms of the GNU General Public License (version 2) as published by the
\r
25 Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
\r
27 >>! NOTE: The modification to the GPL is included to allow you to !<<
\r
28 >>! distribute a combined work that includes FreeRTOS without being !<<
\r
29 >>! obliged to provide the source code for proprietary components !<<
\r
30 >>! outside of the FreeRTOS kernel. !<<
\r
32 FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
\r
33 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
\r
34 FOR A PARTICULAR PURPOSE. Full license text is available from the following
\r
35 link: http://www.freertos.org/a00114.html
\r
39 ***************************************************************************
\r
41 * Having a problem? Start by reading the FAQ "My application does *
\r
42 * not run, what could be wrong?" *
\r
44 * http://www.FreeRTOS.org/FAQHelp.html *
\r
46 ***************************************************************************
\r
48 http://www.FreeRTOS.org - Documentation, books, training, latest versions,
\r
49 license and Real Time Engineers Ltd. contact details.
\r
51 http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
\r
52 including FreeRTOS+Trace - an indispensable productivity tool, a DOS
\r
53 compatible FAT file system, and our tiny thread aware UDP/IP stack.
\r
55 http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
\r
56 Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
\r
57 licenses offer ticketed support, indemnification and middleware.
\r
59 http://www.SafeRTOS.com - High Integrity Systems also provide a safety
\r
60 engineered and independently SIL3 certified version for use in safety and
\r
61 mission critical applications that require provable dependability.
\r
67 * Creates eight tasks, each of which loops continuously performing a floating
\r
68 * point calculation - using single precision variables.
\r
70 * All the tasks run at the idle priority and never block or yield. This causes
\r
71 * all eight tasks to time slice with the idle task. Running at the idle priority
\r
72 * means that these tasks will get pre-empted any time another task is ready to run
\r
73 * or a time slice occurs. More often than not the pre-emption will occur mid
\r
74 * calculation, creating a good test of the schedulers context switch mechanism - a
\r
75 * calculation producing an unexpected result could be a symptom of a corruption in
\r
76 * the context of a task.
\r
82 /* Scheduler include files. */
\r
83 #include "FreeRTOS.h"
\r
86 /* Demo program include files. */
\r
89 #define mathSTACK_SIZE configMINIMAL_STACK_SIZE
\r
90 #define mathNUMBER_OF_TASKS ( 8 )
\r
92 /* Four tasks, each of which performs a different floating point calculation.
\r
93 Each of the four is created twice. */
\r
94 static portTASK_FUNCTION_PROTO( vCompetingMathTask1, pvParameters );
\r
95 static portTASK_FUNCTION_PROTO( vCompetingMathTask2, pvParameters );
\r
96 static portTASK_FUNCTION_PROTO( vCompetingMathTask3, pvParameters );
\r
97 static portTASK_FUNCTION_PROTO( vCompetingMathTask4, pvParameters );
\r
99 /* These variables are used to check that all the tasks are still running. If a
\r
100 task gets a calculation wrong it will
\r
101 stop incrementing its check variable. */
\r
102 static volatile uint16_t usTaskCheck[ mathNUMBER_OF_TASKS ] = { ( uint16_t ) 0 };
\r
104 /*-----------------------------------------------------------*/
\r
106 void vStartMathTasks( UBaseType_t uxPriority )
\r
108 xTaskCreate( vCompetingMathTask1, "Math1", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 0 ] ), uxPriority, NULL );
\r
109 xTaskCreate( vCompetingMathTask2, "Math2", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 1 ] ), uxPriority, NULL );
\r
110 xTaskCreate( vCompetingMathTask3, "Math3", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 2 ] ), uxPriority, NULL );
\r
111 xTaskCreate( vCompetingMathTask4, "Math4", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 3 ] ), uxPriority, NULL );
\r
112 xTaskCreate( vCompetingMathTask1, "Math5", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 4 ] ), uxPriority, NULL );
\r
113 xTaskCreate( vCompetingMathTask2, "Math6", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 5 ] ), uxPriority, NULL );
\r
114 xTaskCreate( vCompetingMathTask3, "Math7", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 6 ] ), uxPriority, NULL );
\r
115 xTaskCreate( vCompetingMathTask4, "Math8", mathSTACK_SIZE, ( void * ) &( usTaskCheck[ 7 ] ), uxPriority, NULL );
\r
117 /*-----------------------------------------------------------*/
\r
119 static portTASK_FUNCTION( vCompetingMathTask1, pvParameters )
\r
121 volatile float f1, f2, f3, f4;
\r
122 volatile uint16_t *pusTaskCheckVariable;
\r
123 volatile float fAnswer;
\r
124 short sError = pdFALSE;
\r
130 fAnswer = ( f1 + f2 ) * f3;
\r
132 /* The variable this task increments to show it is still running is passed in
\r
133 as the parameter. */
\r
134 pusTaskCheckVariable = ( uint16_t * ) pvParameters;
\r
136 /* Keep performing a calculation and checking the result against a constant. */
\r
143 f4 = ( f1 + f2 ) * f3;
\r
145 #if configUSE_PREEMPTION == 0
\r
149 /* If the calculation does not match the expected constant, stop the
\r
150 increment of the check variable. */
\r
151 if( fabs( f4 - fAnswer ) > 0.001F )
\r
156 if( sError == pdFALSE )
\r
158 /* If the calculation has always been correct, increment the check
\r
159 variable so we know this task is still running okay. */
\r
160 ( *pusTaskCheckVariable )++;
\r
163 #if configUSE_PREEMPTION == 0
\r
169 /*-----------------------------------------------------------*/
\r
171 static portTASK_FUNCTION( vCompetingMathTask2, pvParameters )
\r
173 volatile float f1, f2, f3, f4;
\r
174 volatile uint16_t *pusTaskCheckVariable;
\r
175 volatile float fAnswer;
\r
176 short sError = pdFALSE;
\r
182 fAnswer = ( f1 / f2 ) * f3;
\r
185 /* The variable this task increments to show it is still running is passed in
\r
186 as the parameter. */
\r
187 pusTaskCheckVariable = ( uint16_t * ) pvParameters;
\r
189 /* Keep performing a calculation and checking the result against a constant. */
\r
196 f4 = ( f1 / f2 ) * f3;
\r
198 #if configUSE_PREEMPTION == 0
\r
202 /* If the calculation does not match the expected constant, stop the
\r
203 increment of the check variable. */
\r
204 if( fabs( f4 - fAnswer ) > 0.001F )
\r
209 if( sError == pdFALSE )
\r
211 /* If the calculation has always been correct, increment the check
\r
212 variable so we know
\r
213 this task is still running okay. */
\r
214 ( *pusTaskCheckVariable )++;
\r
217 #if configUSE_PREEMPTION == 0
\r
222 /*-----------------------------------------------------------*/
\r
224 static portTASK_FUNCTION( vCompetingMathTask3, pvParameters )
\r
226 volatile float *pfArray, fTotal1, fTotal2, fDifference, fPosition;
\r
227 volatile uint16_t *pusTaskCheckVariable;
\r
228 const size_t xArraySize = 10;
\r
230 short sError = pdFALSE;
\r
232 /* The variable this task increments to show it is still running is passed in
\r
233 as the parameter. */
\r
234 pusTaskCheckVariable = ( uint16_t * ) pvParameters;
\r
236 pfArray = ( float * ) pvPortMalloc( xArraySize * sizeof( float ) );
\r
238 /* Keep filling an array, keeping a running total of the values placed in the
\r
239 array. Then run through the array adding up all the values. If the two totals
\r
240 do not match, stop the check variable from incrementing. */
\r
247 for( xPosition = 0; xPosition < xArraySize; xPosition++ )
\r
249 pfArray[ xPosition ] = fPosition + 5.5F;
\r
250 fTotal1 += fPosition + 5.5F;
\r
253 #if configUSE_PREEMPTION == 0
\r
257 for( xPosition = 0; xPosition < xArraySize; xPosition++ )
\r
259 fTotal2 += pfArray[ xPosition ];
\r
262 fDifference = fTotal1 - fTotal2;
\r
263 if( fabs( fDifference ) > 0.001F )
\r
268 #if configUSE_PREEMPTION == 0
\r
272 if( sError == pdFALSE )
\r
274 /* If the calculation has always been correct, increment the check
\r
275 variable so we know this task is still running okay. */
\r
276 ( *pusTaskCheckVariable )++;
\r
280 /*-----------------------------------------------------------*/
\r
282 static portTASK_FUNCTION( vCompetingMathTask4, pvParameters )
\r
284 volatile float *pfArray, fTotal1, fTotal2, fDifference, fPosition;
\r
285 volatile uint16_t *pusTaskCheckVariable;
\r
286 const size_t xArraySize = 10;
\r
288 short sError = pdFALSE;
\r
290 /* The variable this task increments to show it is still running is passed in
\r
291 as the parameter. */
\r
292 pusTaskCheckVariable = ( uint16_t * ) pvParameters;
\r
294 pfArray = ( float * ) pvPortMalloc( xArraySize * sizeof( float ) );
\r
296 /* Keep filling an array, keeping a running total of the values placed in the
\r
297 array. Then run through the array adding up all the values. If the two totals
\r
298 do not match, stop the check variable from incrementing. */
\r
305 for( xPosition = 0; xPosition < xArraySize; xPosition++ )
\r
307 pfArray[ xPosition ] = fPosition * 12.123F;
\r
308 fTotal1 += fPosition * 12.123F;
\r
311 #if configUSE_PREEMPTION == 0
\r
315 for( xPosition = 0; xPosition < xArraySize; xPosition++ )
\r
317 fTotal2 += pfArray[ xPosition ];
\r
320 fDifference = fTotal1 - fTotal2;
\r
321 if( fabs( fDifference ) > 0.001F )
\r
326 #if configUSE_PREEMPTION == 0
\r
330 if( sError == pdFALSE )
\r
332 /* If the calculation has always been correct, increment the check
\r
333 variable so we know this task is still running okay. */
\r
334 ( *pusTaskCheckVariable )++;
\r
338 /*-----------------------------------------------------------*/
\r
340 /* This is called to check that all the created tasks are still running. */
\r
341 BaseType_t xAreMathsTaskStillRunning( void )
\r
343 /* Keep a history of the check variables so we know if they have been incremented
\r
344 since the last call. */
\r
345 static uint16_t usLastTaskCheck[ mathNUMBER_OF_TASKS ] = { ( uint16_t ) 0 };
\r
346 BaseType_t xReturn = pdTRUE, xTask;
\r
348 /* Check the maths tasks are still running by ensuring their check variables
\r
349 are still incrementing. */
\r
350 for( xTask = 0; xTask < mathNUMBER_OF_TASKS; xTask++ )
\r
352 if( usTaskCheck[ xTask ] == usLastTaskCheck[ xTask ] )
\r
354 /* The check has not incremented so an error exists. */
\r
358 usLastTaskCheck[ xTask ] = usTaskCheck[ xTask ];
\r