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/*
FreeRTOS.org V5.2.0 - Copyright (C) 2003-2009 Richard Barry.
This file is part of the FreeRTOS.org distribution.
FreeRTOS.org 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.
FreeRTOS.org 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 along
with FreeRTOS.org; if not, write to the Free Software Foundation, Inc., 59
Temple Place, Suite 330, Boston, MA 02111-1307 USA.
A special exception to the GPL is included to allow you to distribute a
combined work that includes FreeRTOS.org without being obliged to provide
the source code for any proprietary components. See the licensing section
of http://www.FreeRTOS.org for full details.
***************************************************************************
* *
* Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation *
* *
* This is a concise, step by step, 'hands on' guide that describes both *
* general multitasking concepts and FreeRTOS specifics. It presents and *
* explains numerous examples that are written using the FreeRTOS API. *
* Full source code for all the examples is provided in an accompanying *
* .zip file. *
* *
***************************************************************************
1 tab == 4 spaces!
Please ensure to read the configuration and relevant port sections of the
online documentation.
http://www.FreeRTOS.org - Documentation, latest information, license and
contact details.
http://www.SafeRTOS.com - A version that is certified for use in safety
critical systems.
http://www.OpenRTOS.com - Commercial support, development, porting,
licensing and training services.
*/
/*
*
* main() creates all the demo application tasks, then starts the scheduler.
* The WEB documentation provides more details of the demo application tasks.
*
* main.c also creates a task called "Check". This only executes every three
* seconds but has the highest priority so is guaranteed to get processor time.
* Its main function is to check that all the other tasks are still operational.
* Each task (other than the "flash" tasks) maintains a unique count that is
* incremented each time the task successfully completes its function. Should
* any error occur within such a task the count is permanently halted. The
* check task inspects the count of each task to ensure it has changed since
* the last time the check task executed. If all the count variables have
* changed all the tasks are still executing error free, and the check task
* toggles the onboard LED. Should any task contain an error at any time
* the LED toggle rate will change from 3 seconds to 500ms.
*
* This file also includes the functionality implemented within the
* standard demo application file integer.c. This is done to demonstrate the
* use of an idle hook. See the documentation within integer.c for the
* rationale of the integer task functionality.
* */
/* Kernel includes. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"
#include "cpu.h"
/* special prototypes for memory-banked functions */
void vStartPolledQueueTasks( unsigned portBASE_TYPE uxPriority );
portBASE_TYPE xArePollingQueuesStillRunning( void );
/* Demo application includes. */
#include "flash.h"
#include "PollQ.h"
#include "dynamic.h"
#include "partest.h"
#include "comtest2.h"
#include "BlockQ.h"
#include "integer.h"
#include "death.h"
/*-----------------------------------------------------------
Definitions.
-----------------------------------------------------------*/
/* Priorities assigned to demo application tasks. */
#define mainFLASH_PRIORITY ( tskIDLE_PRIORITY + 2 )
#define mainCHECK_TASK_PRIORITY ( tskIDLE_PRIORITY + 3 )
#define mainQUEUE_POLL_PRIORITY ( tskIDLE_PRIORITY + 1 )
#define mainCOM_TEST_PRIORITY ( tskIDLE_PRIORITY + 2 )
#define mainBLOCK_Q_PRIORITY ( tskIDLE_PRIORITY + 2 )
#define mainDEATH_PRIORITY ( tskIDLE_PRIORITY + 1 )
/* LED that is toggled by the check task. The check task periodically checks
that all the other tasks are operating without error. If no errors are found
the LED is toggled with mainCHECK_PERIOD frequency. If an error is found
then the toggle rate increases to mainERROR_CHECK_PERIOD. */
#define mainCHECK_TASK_LED ( 7 )
#define mainCHECK_PERIOD ( ( portTickType ) 3000 / portTICK_RATE_MS )
#define mainERROR_CHECK_PERIOD ( ( portTickType ) 500 / portTICK_RATE_MS )
/* The constants used in the idle task calculation. */
#define intgCONST1 ( ( portLONG ) 123 )
#define intgCONST2 ( ( portLONG ) 234567 )
#define intgCONST3 ( ( portLONG ) -3 )
#define intgCONST4 ( ( portLONG ) 7 )
#define intgEXPECTED_ANSWER ( ( ( intgCONST1 + intgCONST2 ) * intgCONST3 ) / intgCONST4 )
/* Baud rate used by the serial port tasks (ComTest tasks).
IMPORTANT: The function COM0_SetBaudRateValue() which is generated by the
Processor Expert is used to set the baud rate. As configured in the FreeRTOS
download this value must be one of the following:
0 to configure for 38400 baud.
1 to configure for 19200 baud.
2 to configure for 9600 baud.
3 to configure for 4800 baud. */
#define mainCOM_TEST_BAUD_RATE ( ( unsigned portLONG ) 2 )
/* LED used by the serial port tasks. This is toggled on each character Tx,
and mainCOM_TEST_LED + 1 is toggles on each character Rx. */
#define mainCOM_TEST_LED ( 3 )
/*-----------------------------------------------------------
Local functions prototypes.
-----------------------------------------------------------*/
/*
* The 'Check' task function. See the explanation at the top of the file.
*/
static void ATTR_BANK1 vErrorChecks( void* pvParameters );
/*
* The idle task hook - in which the integer task is implemented. See the
* explanation at the top of the file.
*/
void ATTR_BANK0 vApplicationIdleHook( void );
/*
* Checks the unique counts of other tasks to ensure they are still operational.
*/
static portLONG ATTR_BANK0 prvCheckOtherTasksAreStillRunning( void );
/*-----------------------------------------------------------
Local variables.
-----------------------------------------------------------*/
/* A few tasks are defined within this file. This flag is used to indicate
their status. If an error is detected in one of the locally defined tasks then
this flag is set to pdTRUE. */
portBASE_TYPE xLocalError = pdFALSE;
/*-----------------------------------------------------------*/
/* This is called from startup. */
int ATTR_BANK0 main ( void )
{
/* Start some of the standard demo tasks. */
vStartLEDFlashTasks( mainFLASH_PRIORITY );
vStartPolledQueueTasks( mainQUEUE_POLL_PRIORITY );
vStartDynamicPriorityTasks();
vAltStartComTestTasks( mainCOM_TEST_PRIORITY, mainCOM_TEST_BAUD_RATE, mainCOM_TEST_LED );
vStartBlockingQueueTasks( mainBLOCK_Q_PRIORITY );
vStartIntegerMathTasks( tskIDLE_PRIORITY );
/* Start the locally defined tasks. There is also a task implemented as
the idle hook. */
xTaskCreate( vErrorChecks, "Check", configMINIMAL_STACK_SIZE, NULL, mainCHECK_TASK_PRIORITY, NULL );
/* Must be the last demo created. */
vCreateSuicidalTasks( mainDEATH_PRIORITY );
/* All the tasks have been created - start the scheduler. */
vTaskStartScheduler();
/* Should not reach here! */
for( ;; );
return 0;
}
/*-----------------------------------------------------------*/
static void vErrorChecks( void *pvParameters )
{
portTickType xDelayPeriod = mainCHECK_PERIOD;
portTickType xLastWakeTime;
/* Initialise xLastWakeTime to ensure the first call to vTaskDelayUntil()
functions correctly. */
xLastWakeTime = xTaskGetTickCount();
for( ;; )
{
/* Delay until it is time to execute again. The delay period is
shorter following an error. */
vTaskDelayUntil( &xLastWakeTime, xDelayPeriod );
/* Check all the demo application tasks are executing without
error. If an error is found the delay period is shortened - this
has the effect of increasing the flash rate of the 'check' task
LED. */
if( prvCheckOtherTasksAreStillRunning() == pdFAIL )
{
/* An error has been detected in one of the tasks - flash faster. */
xDelayPeriod = mainERROR_CHECK_PERIOD;
}
/* Toggle the LED each cycle round. */
vParTestToggleLED( mainCHECK_TASK_LED );
}
}
/*-----------------------------------------------------------*/
static portLONG prvCheckOtherTasksAreStillRunning( void )
{
portBASE_TYPE xAllTasksPassed = pdPASS;
if( xArePollingQueuesStillRunning() != pdTRUE )
{
xAllTasksPassed = pdFAIL;
}
if( xAreDynamicPriorityTasksStillRunning() != pdTRUE )
{
xAllTasksPassed = pdFAIL;
}
if( xAreComTestTasksStillRunning() != pdTRUE )
{
xAllTasksPassed = pdFALSE;
}
if( xAreIntegerMathsTaskStillRunning() != pdTRUE )
{
xAllTasksPassed = pdFALSE;
}
if( xAreBlockingQueuesStillRunning() != pdTRUE )
{
xAllTasksPassed = pdFALSE;
}
if( xIsCreateTaskStillRunning() != pdTRUE )
{
xAllTasksPassed = pdFALSE;
}
/* Also check the status flag for the tasks defined within this function. */
if( xLocalError != pdFALSE )
{
xAllTasksPassed = pdFAIL;
}
return xAllTasksPassed;
}
/*-----------------------------------------------------------*/
void vApplicationIdleHook( void )
{
/* This variable is effectively set to a constant so it is made volatile to
ensure the compiler does not just get rid of it. */
volatile portLONG lValue;
/* Keep performing a calculation and checking the result against a constant. */
/* Perform the calculation. This will store partial value in
registers, resulting in a good test of the context switch mechanism. */
lValue = intgCONST1;
lValue += intgCONST2;
lValue *= intgCONST3;
lValue /= intgCONST4;
/* Did we perform the calculation correctly with no corruption? */
if( lValue != intgEXPECTED_ANSWER )
{
/* Error! */
portENTER_CRITICAL();
xLocalError = pdTRUE;
portEXIT_CRITICAL();
}
/* Yield in case cooperative scheduling is being used. */
#if configUSE_PREEMPTION == 0
{
taskYIELD();
}
#endif
}
/*-----------------------------------------------------------*/
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