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/*
FreeRTOS V7.5.1 - Copyright (C) 2013 Real Time Engineers Ltd.
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that has become a de facto standard. *
* *
* Help yourself get started quickly and support the FreeRTOS *
* project by purchasing a FreeRTOS tutorial book, reference *
* manual, or both from: http://www.FreeRTOS.org/Documentation *
* *
* Thank you! *
* *
***************************************************************************
This file is part of the FreeRTOS distribution.
FreeRTOS is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License (version 2) as published by the
Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
>>! NOTE: The modification to the GPL is included to allow you to distribute
>>! a combined work that includes FreeRTOS without being obliged to provide
>>! the source code for proprietary components outside of the FreeRTOS
>>! kernel.
FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. Full license text is available from the following
link: http://www.freertos.org/a00114.html
1 tab == 4 spaces!
***************************************************************************
* *
* Having a problem? Start by reading the FAQ "My application does *
* not run, what could be wrong?" *
* *
* http://www.FreeRTOS.org/FAQHelp.html *
* *
***************************************************************************
http://www.FreeRTOS.org - Documentation, books, training, latest versions,
license and Real Time Engineers Ltd. contact details.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
compatible FAT file system, and our tiny thread aware UDP/IP stack.
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and middleware.
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
engineered and independently SIL3 certified version for use in safety and
mission critical applications that require provable dependability.
1 tab == 4 spaces!
*/
/*
* Creates one or more tasks that repeatedly perform a set of integer
* calculations. The result of each run-time calculation is compared to the
* known expected result - with a mismatch being indicative of an error in the
* context switch mechanism.
*/
#include <stdlib.h>
/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
/* Demo program include files. */
#include "integer.h"
/* The constants used in the calculation. */
#define intgCONST1 ( ( long ) 123 )
#define intgCONST2 ( ( long ) 234567 )
#define intgCONST3 ( ( long ) -3 )
#define intgCONST4 ( ( long ) 7 )
#define intgEXPECTED_ANSWER ( ( ( intgCONST1 + intgCONST2 ) * intgCONST3 ) / intgCONST4 )
#define intgSTACK_SIZE configMINIMAL_STACK_SIZE
/* As this is the minimal version, we will only create one task. */
#define intgNUMBER_OF_TASKS ( 1 )
/* The task function. Repeatedly performs a 32 bit calculation, checking the
result against the expected result. If the result is incorrect then the
context switch must have caused some corruption. */
static portTASK_FUNCTION_PROTO( vCompeteingIntMathTask, pvParameters );
/* Variables that are set to true within the calculation task to indicate
that the task is still executing. The check task sets the variable back to
false, flagging an error if the variable is still false the next time it
is called. */
static volatile signed portBASE_TYPE xTaskCheck[ intgNUMBER_OF_TASKS ] = { ( signed portBASE_TYPE ) pdFALSE };
/*-----------------------------------------------------------*/
void vStartIntegerMathTasks( unsigned portBASE_TYPE uxPriority )
{
short sTask;
for( sTask = 0; sTask < intgNUMBER_OF_TASKS; sTask++ )
{
xTaskCreate( vCompeteingIntMathTask, ( signed char * ) "IntMath", intgSTACK_SIZE, ( void * ) &( xTaskCheck[ sTask ] ), uxPriority, ( xTaskHandle * ) NULL );
}
}
/*-----------------------------------------------------------*/
static portTASK_FUNCTION( vCompeteingIntMathTask, pvParameters )
{
/* These variables are all effectively set to constants so they are volatile to
ensure the compiler does not just get rid of them. */
volatile long lValue;
short sError = pdFALSE;
volatile signed portBASE_TYPE *pxTaskHasExecuted;
/* Set a pointer to the variable we are going to set to true each
iteration. This is also a good test of the parameter passing mechanism
within each port. */
pxTaskHasExecuted = ( volatile signed portBASE_TYPE * ) pvParameters;
/* Keep performing a calculation and checking the result against a constant. */
for( ;; )
{
/* Perform the calculation. This will store partial value in
registers, resulting in a good test of the context switch mechanism. */
lValue = intgCONST1;
lValue += intgCONST2;
/* Yield in case cooperative scheduling is being used. */
#if configUSE_PREEMPTION == 0
{
taskYIELD();
}
#endif
/* Finish off the calculation. */
lValue *= intgCONST3;
lValue /= intgCONST4;
/* If the calculation is found to be incorrect we stop setting the
TaskHasExecuted variable so the check task can see an error has
occurred. */
if( lValue != intgEXPECTED_ANSWER ) /*lint !e774 volatile used to prevent this being optimised out. */
{
sError = pdTRUE;
}
if( sError == pdFALSE )
{
/* We have not encountered any errors, so set the flag that show
we are still executing. This will be periodically cleared by
the check task. */
portENTER_CRITICAL();
*pxTaskHasExecuted = pdTRUE;
portEXIT_CRITICAL();
}
/* Yield in case cooperative scheduling is being used. */
#if configUSE_PREEMPTION == 0
{
taskYIELD();
}
#endif
}
}
/*-----------------------------------------------------------*/
/* This is called to check that all the created tasks are still running. */
portBASE_TYPE xAreIntegerMathsTaskStillRunning( void )
{
portBASE_TYPE xReturn = pdTRUE;
short sTask;
/* Check the maths tasks are still running by ensuring their check variables
are still being set to true. */
for( sTask = 0; sTask < intgNUMBER_OF_TASKS; sTask++ )
{
if( xTaskCheck[ sTask ] == pdFALSE )
{
/* The check has not incremented so an error exists. */
xReturn = pdFALSE;
}
/* Reset the check variable so we can tell if it has been set by
the next time around. */
xTaskCheck[ sTask ] = pdFALSE;
}
return xReturn;
}
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