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/*
FreeRTOS.org V5.1.1 - Copyright (C) 2003-2008 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 as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
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 can be applied should you wish 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 of how and when the exception
can be applied.
***************************************************************************
***************************************************************************
* *
* SAVE TIME AND MONEY! We can port FreeRTOS.org to your own hardware, *
* and even write all or part of your application on your behalf. *
* See http://www.OpenRTOS.com for details of the services we provide to *
* expedite your project. *
* *
***************************************************************************
***************************************************************************
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.
*/
/*
* THIS DEMO APPLICATION REQUIRES A LOOPBACK CONNECTOR TO BE FITTED TO THE PIC
* USART PORT - connect pin 2 to pin 3 on J2.
*
* Instead of the normal single demo application, the PIC18F demo is split
* into several smaller programs of which this is the third. 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 RTOSDemo3 project is configured for a PIC18F452 device. Main3.c starts
* 5 tasks (including the idle task).
*
* The first task repeatedly transmits a string of characters on the PIC USART
* port. The second task receives the characters, checking that the correct
* sequence is maintained (i.e. what is transmitted is identical to that
* received). Each transmitted and each received character causes an LED to
* flash. See demo/common/minimal/comtest. c for more information.
*
* The third task continuously performs a 32 bit calculation. This is a good
* test of the context switch mechanism as the 8 bit architecture requires
* the use of several file registers to perform the 32 bit operations. See
* demo/common/minimal/integer. c for more information.
*
* The third task is the check task. This periodically checks that the other
* tasks are still running and have not experienced any errors. If no errors
* have been reported by either the comms or integer tasks an LED is flashed
* with a frequency mainNO_ERROR_CHECK_PERIOD. If an error is discovered the
* frequency is increased to mainERROR_FLASH_RATE.
*
* The check task also provides a visual indication of a system reset by
* flashing the one remaining LED (mainRESET_LED) when it starts. After
* this initial flash mainRESET_LED should remain off.
*
* 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 portLONG.
*/
/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
/* Demo app include files. */
#include "partest.h"
#include "serial.h"
#include "comtest.h"
#include "integer.h"
/* Priority definitions for the LED tasks. Other tasks just use the idle
priority. */
#define mainCOMM_TEST_PRIORITY ( tskIDLE_PRIORITY + ( unsigned portBASE_TYPE ) 2 )
#define mainCHECK_TASK_PRIORITY ( tskIDLE_PRIORITY + ( unsigned portBASE_TYPE ) 3 )
/* 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 )
/* The period for which mainRESET_LED remain on every reset. */
#define mainRESET_LED_PERIOD ( ( portTickType ) 500 / portTICK_RATE_MS )
/* The LED that is toggled whenever a character is transmitted.
mainCOMM_TX_RX_LED + 1 will be toggled every time a character is received. */
#define mainCOMM_TX_RX_LED ( ( unsigned portBASE_TYPE ) 2 )
/* The LED that is flashed by the check task at a rate that indicates the
error status. */
#define mainCHECK_TASK_LED ( ( unsigned portBASE_TYPE ) 1 )
/* The LED that is flashed once upon every reset. */
#define mainRESET_LED ( ( unsigned portBASE_TYPE ) 0 )
/* Constants required for the communications. */
#define mainCOMMS_QUEUE_LENGTH ( ( unsigned portBASE_TYPE ) 5 )
#define mainBAUD_RATE ( ( unsigned portLONG ) 57600 )
/*-----------------------------------------------------------*/
/*
* Task function which periodically checks the other tasks for errors. Flashes
* an LED at a rate that indicates whether an error has ever been detected.
*/
static void vErrorChecks( void *pvParameters );
/*-----------------------------------------------------------*/
/* Creates the tasks, then starts the scheduler. */
void main( void )
{
/* Initialise the required hardware. */
vParTestInitialise();
/* Initialise the block memory allocator. */
vPortInitialiseBlocks();
/* Start the standard comtest tasks as defined in demo/common/minimal. */
vAltStartComTestTasks( mainCOMM_TEST_PRIORITY, mainBAUD_RATE, mainCOMM_TX_RX_LED );
/* Start the standard 32bit calculation task as defined in
demo/common/minimal. */
vStartIntegerMathTasks( tskIDLE_PRIORITY );
/* Start the check task defined in this file. */
xTaskCreate( vErrorChecks, ( const portCHAR * const ) "Check", configMINIMAL_STACK_SIZE, NULL, mainCHECK_TASK_PRIORITY, NULL );
/* Start the scheduler. This will never return. */
vTaskStartScheduler();
}
/*-----------------------------------------------------------*/
static void vErrorChecks( void *pvParameters )
{
portTickType xDelayTime = mainNO_ERROR_CHECK_PERIOD;
volatile unsigned portLONG ulDummy = 3UL;
/* Toggle the LED so we can see when a reset occurs. */
vParTestSetLED( mainRESET_LED, pdTRUE );
vTaskDelay( mainRESET_LED_PERIOD );
vParTestSetLED( mainRESET_LED, pdFALSE );
/* 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 );
/* Perform an integer calculation - just to ensure the registers
get used. The result is not important. */
ulDummy *= 3UL;
/* Check all the other tasks are running, and running without ever
having an error. The delay period is lowered if an error is reported,
causing the LED to flash at a higher rate. */
if( xAreIntegerMathsTaskStillRunning() == pdFALSE )
{
xDelayTime = mainERROR_CHECK_PERIOD;
}
if( xAreComTestTasksStillRunning() == pdFALSE )
{
xDelayTime = mainERROR_CHECK_PERIOD;
}
/* Flash the LED for visual feedback. The rate of the flash will
indicate the health of the system. */
vParTestToggleLED( mainCHECK_TASK_LED );
}
}
/*-----------------------------------------------------------*/
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