| /* | |
| FreeRTOS V6.0.0 - Copyright (C) 2009 Real Time Engineers Ltd. | |
| *************************************************************************** | |
| * * | |
| * If you are: * | |
| * * | |
| * + New to FreeRTOS, * | |
| * + Wanting to learn FreeRTOS or multitasking in general quickly * | |
| * + Looking for basic training, * | |
| * + Wanting to improve your FreeRTOS skills and productivity * | |
| * * | |
| * then take a look at the FreeRTOS eBook * | |
| * * | |
| * "Using the FreeRTOS Real Time Kernel - a Practical Guide" * | |
| * http://www.FreeRTOS.org/Documentation * | |
| * * | |
| * A pdf reference manual is also available. Both are usually delivered * | |
| * to your inbox within 20 minutes to two hours when purchased between 8am * | |
| * and 8pm GMT (although please allow up to 24 hours in case of * | |
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| * * | |
| *************************************************************************** | |
| 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 exception 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 it | |
| can be viewed here: http://www.freertos.org/a00114.html and also obtained | |
| by writing to Richard Barry, contact details for whom are available on the | |
| FreeRTOS WEB site. | |
| 1 tab == 4 spaces! | |
| 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 long. | |
| */ | |
| /* 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 long ) 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 char * 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 long 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 ); | |
| } | |
| } | |
| /*-----------------------------------------------------------*/ | |