/* 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. */ /* * Instead of the normal single demo application, the PIC18F demo is split * into several smaller programs of which this is the second. 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 RTOSDemo2 project is configured for a PIC18F452 device. Main2.c starts * 5 tasks (including the idle task). * * The first, second and third tasks do nothing but flash an LED. This gives * visual feedback that everything is executing as expected. One task flashes * an LED every 333ms (i.e. on and off every 333/2 ms), then next every 666ms * and the last every 999ms. * * The last 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. * should the calculation ever provide an incorrect result the final LED is * turned on. * * 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 portLONG. */ /* Scheduler include files. */ #include "FreeRTOS.h" #include "task.h" /* Demo app include files. */ #include "flash.h" #include "partest.h" #include "serial.h" /* Priority definitions for the LED tasks. Other tasks just use the idle priority. */ #define mainLED_FLASH_PRIORITY ( tskIDLE_PRIORITY + ( unsigned portBASE_TYPE ) 1 ) /* The LED that is lit when should the calculation fail. */ #define mainCHECK_TASK_LED ( ( unsigned portBASE_TYPE ) 3 ) /* Constants required for the communications. Only one character is ever transmitted. */ #define mainCOMMS_QUEUE_LENGTH ( ( unsigned portBASE_TYPE ) 5 ) #define mainNO_BLOCK ( ( portTickType ) 0 ) #define mainBAUD_RATE ( ( unsigned portLONG ) 9600 ) /* * The task that performs the 32 bit calculation at the idle priority. */ static void vCalculationTask( void *pvParameters ); /*-----------------------------------------------------------*/ /* 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 LED flash tasks as defined in demo/common/minimal. */ vStartLEDFlashTasks( mainLED_FLASH_PRIORITY ); /* Start the check task defined in this file. */ xTaskCreate( vCalculationTask, ( const portCHAR * const ) "Check", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY, NULL ); /* Start the scheduler. */ vTaskStartScheduler(); } /*-----------------------------------------------------------*/ static void vCalculationTask( void *pvParameters ) { volatile unsigned long ulCalculatedValue; /* Volatile to ensure optimisation is minimal. */ /* Continuously perform a calculation. If the calculation result is ever incorrect turn the LED on. */ for( ;; ) { /* A good optimising compiler would just remove all this! */ ulCalculatedValue = 1234UL; ulCalculatedValue *= 99UL; if( ulCalculatedValue != 122166UL ) { vParTestSetLED( mainCHECK_TASK_LED, pdTRUE ); } ulCalculatedValue *= 9876UL; if( ulCalculatedValue != 1206511416UL ) { vParTestSetLED( mainCHECK_TASK_LED, pdTRUE ); } ulCalculatedValue /= 15UL; if( ulCalculatedValue != 80434094UL ) { vParTestSetLED( mainCHECK_TASK_LED, pdTRUE ); } ulCalculatedValue += 918273UL; if( ulCalculatedValue != 81352367UL ) { vParTestSetLED( mainCHECK_TASK_LED, pdTRUE ); } } } /*-----------------------------------------------------------*/