/* * FreeRTOS Kernel V10.2.1 * Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a copy of * this software and associated documentation files (the "Software"), to deal in * the Software without restriction, including without limitation the rights to * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of * the Software, and to permit persons to whom the Software is furnished to do so, * subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * http://www.FreeRTOS.org * http://aws.amazon.com/freertos * * 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 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 TickType_t rather than unsigned long. */ /* 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 ( ( TickType_t ) 0 ) #define mainBAUD_RATE ( ( unsigned long ) 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, "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 ); } } } /*-----------------------------------------------------------*/