FreeRTOS/Demo/PIC18_MPLAB/main1.c - third_party/github/FreeRTOS/FreeRTOS-Kernel - Git at Google

 /*
     FreeRTOS V7.5.0 - 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!
 */

 /*
  * Instead of the normal single demo application, the PIC18F demo is split
  * into several smaller programs of which this is the first.  This enables the
  * demo's to be executed on the RAM limited 40 pin devices.  The 64 and 80 pin
  * devices require a more costly development platform and are not so readily
  * available.
  *
  * The RTOSDemo1 project is configured for a PIC18F452 device.  Main1.c starts 5
  * tasks (including the idle task).
  *
  * The first task runs at the idle priority.  It repeatedly performs a 32bit
  * calculation and checks it's result against the expected value.  This checks
  * that the temporary storage utilised by the compiler to hold intermediate
  * results does not get corrupted when the task gets switched in and out.  See
  * demo/common/minimal/integer.c for more information.
  *
  * The second and third tasks pass an incrementing value between each other on
  * a message queue.  See demo/common/minimal/PollQ.c for more information.
  *
  * Main1.c also creates a check task.  This periodically checks that all the
  * other tasks are still running and have not experienced any unexpected
  * results.  If all the other tasks are executing correctly an LED is flashed
  * once every mainCHECK_PERIOD milliseconds.  If any of the tasks have not
  * executed, or report and error, the frequency of the LED flash will increase
  * to mainERROR_FLASH_RATE.
  *
  * On entry to main an 'X' is transmitted.  Monitoring the serial port using a
  * dumb terminal allows for verification that the device is not continuously
  * being reset (no more than one 'X' should be transmitted).
  *
  * http://www.FreeRTOS.org contains important information on the use of the
  * PIC18F port.
  */

 /*
 Changes from V2.0.0

 	+ Delay periods are now specified using variables and constants of
 	  portTickType rather than unsigned long.
 */

 /* Scheduler include files. */
 #include "FreeRTOS.h"
 #include "task.h"

 /* Demo app include files. */
 #include "PollQ.h"
 #include "integer.h"
 #include "partest.h"
 #include "serial.h"

 /* The period between executions of the check task before and after an error
 has been discovered.  If an error has been discovered the check task runs
 more frequently - increasing the LED flash rate. */
 #define mainNO_ERROR_CHECK_PERIOD		( ( portTickType ) 1000 / portTICK_RATE_MS )
 #define mainERROR_CHECK_PERIOD			( ( portTickType ) 100 / portTICK_RATE_MS )

 /* Priority definitions for some of the tasks.  Other tasks just use the idle
 priority. */
 #define mainQUEUE_POLL_PRIORITY			( tskIDLE_PRIORITY + 2 )
 #define mainCHECK_TASK_PRIORITY			( tskIDLE_PRIORITY + 3 )

 /* The LED that is flashed by the check task. */
 #define mainCHECK_TASK_LED				( 0 )

 /* Constants required for the communications.  Only one character is ever
 transmitted. */
 #define mainCOMMS_QUEUE_LENGTH			( 5 )
 #define mainNO_BLOCK					( ( portTickType ) 0 )
 #define mainBAUD_RATE					( ( unsigned long ) 9600 )

 /*
  * The task function for the "Check" task.
  */
 static void vErrorChecks( void *pvParameters );

 /*
  * Checks the unique counts of other tasks to ensure they are still operational.
  * Returns pdTRUE if an error is detected, otherwise pdFALSE.
  */
 static portBASE_TYPE prvCheckOtherTasksAreStillRunning( void );

 /*-----------------------------------------------------------*/

 /* Creates the tasks, then starts the scheduler. */
 void main( void )
 {
 	/* Initialise the required hardware. */
 	vParTestInitialise();
 	vPortInitialiseBlocks();

 	/* Send a character so we have some visible feedback of a reset. */
 	xSerialPortInitMinimal( mainBAUD_RATE, mainCOMMS_QUEUE_LENGTH );
 	xSerialPutChar( NULL, 'X', mainNO_BLOCK );

 	/* Start the standard demo tasks found in the demo\common directory. */
 	vStartIntegerMathTasks( tskIDLE_PRIORITY );
 	vStartPolledQueueTasks( mainQUEUE_POLL_PRIORITY );

 	/* Start the check task defined in this file. */
 	xTaskCreate( vErrorChecks, ( const char * const ) "Check", configMINIMAL_STACK_SIZE, NULL, mainCHECK_TASK_PRIORITY, NULL );

 	/* Start the scheduler.  Will never return here. */
 	vTaskStartScheduler();
 }
 /*-----------------------------------------------------------*/

 static void vErrorChecks( void *pvParameters )
 {
 portTickType xDelayTime = mainNO_ERROR_CHECK_PERIOD;
 portBASE_TYPE xErrorOccurred;

 	/* Cycle for ever, delaying then checking all the other tasks are still
 	operating without error. */
 	for( ;; )
 	{
 		/* Wait until it is time to check the other tasks. */
 		vTaskDelay( xDelayTime );

 		/* Check all the other tasks are running, and running without ever
 		having an error. */
 		xErrorOccurred = prvCheckOtherTasksAreStillRunning();

 		/* If an error was detected increase the frequency of the LED flash. */
 		if( xErrorOccurred == pdTRUE )
 		{
 			xDelayTime = mainERROR_CHECK_PERIOD;
 		}

 		/* Flash the LED for visual feedback. */
 		vParTestToggleLED( mainCHECK_TASK_LED );
 	}
 }
 /*-----------------------------------------------------------*/

 static portBASE_TYPE prvCheckOtherTasksAreStillRunning( void )
 {
 portBASE_TYPE xErrorHasOccurred = pdFALSE;

 	if( xAreIntegerMathsTaskStillRunning() != pdTRUE )
 	{
 		xErrorHasOccurred = pdTRUE;
 	}

 	if( xArePollingQueuesStillRunning() != pdTRUE )
 	{
 		xErrorHasOccurred = pdTRUE;
 	}

 	return xErrorHasOccurred;
 }
 /*-----------------------------------------------------------*/
	/*
	FreeRTOS V7.5.0 - 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!
	*/

	/*
	* Instead of the normal single demo application, the PIC18F demo is split
	* into several smaller programs of which this is the first. This enables the
	* demo's to be executed on the RAM limited 40 pin devices. The 64 and 80 pin
	* devices require a more costly development platform and are not so readily
	* available.
	*
	* The RTOSDemo1 project is configured for a PIC18F452 device. Main1.c starts 5
	* tasks (including the idle task).
	*
	* The first task runs at the idle priority. It repeatedly performs a 32bit
	* calculation and checks it's result against the expected value. This checks
	* that the temporary storage utilised by the compiler to hold intermediate
	* results does not get corrupted when the task gets switched in and out. See
	* demo/common/minimal/integer.c for more information.
	*
	* The second and third tasks pass an incrementing value between each other on
	* a message queue. See demo/common/minimal/PollQ.c for more information.
	*
	* Main1.c also creates a check task. This periodically checks that all the
	* other tasks are still running and have not experienced any unexpected
	* results. If all the other tasks are executing correctly an LED is flashed
	* once every mainCHECK_PERIOD milliseconds. If any of the tasks have not
	* executed, or report and error, the frequency of the LED flash will increase
	* to mainERROR_FLASH_RATE.
	*
	* On entry to main an 'X' is transmitted. Monitoring the serial port using a
	* dumb terminal allows for verification that the device is not continuously
	* being reset (no more than one 'X' should be transmitted).
	*
	* http://www.FreeRTOS.org contains important information on the use of the
	* PIC18F port.
	*/

	/*
	Changes from V2.0.0

	+ Delay periods are now specified using variables and constants of
	portTickType rather than unsigned long.
	*/

	/* Scheduler include files. */
	#include "FreeRTOS.h"
	#include "task.h"

	/* Demo app include files. */
	#include "PollQ.h"
	#include "integer.h"
	#include "partest.h"
	#include "serial.h"

	/* The period between executions of the check task before and after an error
	has been discovered. If an error has been discovered the check task runs
	more frequently - increasing the LED flash rate. */
	#define mainNO_ERROR_CHECK_PERIOD ( ( portTickType ) 1000 / portTICK_RATE_MS )
	#define mainERROR_CHECK_PERIOD ( ( portTickType ) 100 / portTICK_RATE_MS )

	/* Priority definitions for some of the tasks. Other tasks just use the idle
	priority. */
	#define mainQUEUE_POLL_PRIORITY ( tskIDLE_PRIORITY + 2 )
	#define mainCHECK_TASK_PRIORITY ( tskIDLE_PRIORITY + 3 )

	/* The LED that is flashed by the check task. */
	#define mainCHECK_TASK_LED ( 0 )

	/* Constants required for the communications. Only one character is ever
	transmitted. */
	#define mainCOMMS_QUEUE_LENGTH ( 5 )
	#define mainNO_BLOCK ( ( portTickType ) 0 )
	#define mainBAUD_RATE ( ( unsigned long ) 9600 )

	/*
	* The task function for the "Check" task.
	*/
	static void vErrorChecks( void *pvParameters );

	/*
	* Checks the unique counts of other tasks to ensure they are still operational.
	* Returns pdTRUE if an error is detected, otherwise pdFALSE.
	*/
	static portBASE_TYPE prvCheckOtherTasksAreStillRunning( void );

	/-----------------------------------------------------------/

	/* Creates the tasks, then starts the scheduler. */
	void main( void )
	{
	/* Initialise the required hardware. */
	vParTestInitialise();
	vPortInitialiseBlocks();

	/* Send a character so we have some visible feedback of a reset. */
	xSerialPortInitMinimal( mainBAUD_RATE, mainCOMMS_QUEUE_LENGTH );
	xSerialPutChar( NULL, 'X', mainNO_BLOCK );

	/* Start the standard demo tasks found in the demo\common directory. */
	vStartIntegerMathTasks( tskIDLE_PRIORITY );
	vStartPolledQueueTasks( mainQUEUE_POLL_PRIORITY );

	/* Start the check task defined in this file. */
	xTaskCreate( vErrorChecks, ( const char * const ) "Check", configMINIMAL_STACK_SIZE, NULL, mainCHECK_TASK_PRIORITY, NULL );

	/* Start the scheduler. Will never return here. */
	vTaskStartScheduler();
	}
	/-----------------------------------------------------------/

	static void vErrorChecks( void *pvParameters )
	{
	portTickType xDelayTime = mainNO_ERROR_CHECK_PERIOD;
	portBASE_TYPE xErrorOccurred;

	/* Cycle for ever, delaying then checking all the other tasks are still
	operating without error. */
	for( ;; )
	{
	/* Wait until it is time to check the other tasks. */
	vTaskDelay( xDelayTime );

	/* Check all the other tasks are running, and running without ever
	having an error. */
	xErrorOccurred = prvCheckOtherTasksAreStillRunning();

	/* If an error was detected increase the frequency of the LED flash. */
	if( xErrorOccurred == pdTRUE )
	{
	xDelayTime = mainERROR_CHECK_PERIOD;
	}

	/* Flash the LED for visual feedback. */
	vParTestToggleLED( mainCHECK_TASK_LED );
	}
	}
	/-----------------------------------------------------------/

	static portBASE_TYPE prvCheckOtherTasksAreStillRunning( void )
	{
	portBASE_TYPE xErrorHasOccurred = pdFALSE;

	if( xAreIntegerMathsTaskStillRunning() != pdTRUE )
	{
	xErrorHasOccurred = pdTRUE;
	}

	if( xArePollingQueuesStillRunning() != pdTRUE )
	{
	xErrorHasOccurred = pdTRUE;
	}

	return xErrorHasOccurred;
	}
	/-----------------------------------------------------------/