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/*
FreeRTOS V7.4.0 - Copyright (C) 2013 Real Time Engineers Ltd.
FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME. PLEASE VISIT
http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* FreeRTOS tutorial books are available in pdf and paperback. *
* Complete, revised, and edited pdf reference manuals are also *
* available. *
* *
* Purchasing FreeRTOS documentation will not only help you, by *
* ensuring you get running as quickly as possible and with an *
* in-depth knowledge of how to use FreeRTOS, it will also help *
* the FreeRTOS project to continue with its mission of providing *
* professional grade, cross platform, de facto standard solutions *
* for microcontrollers - completely free of charge! *
* *
* >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
* *
* Thank you for using FreeRTOS, and thank you for your support! *
* *
***************************************************************************
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. See the GNU General Public License for more
details. You should have received a copy of the GNU General Public License
and the FreeRTOS license exception along with FreeRTOS; if not itcan be
viewed here: http://www.freertos.org/a00114.html and also obtained by
writing to Real Time Engineers Ltd., contact details for whom are available
on the FreeRTOS WEB site.
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, and our new
fully thread aware and reentrant UDP/IP stack.
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
Integrity Systems, who sell the code with commercial support,
indemnification and middleware, under the OpenRTOS brand.
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.
*/
/*
* 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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