text: /*
   * FreeRTOS V202012.00
   * Copyright (C) 2020 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 );
  		}
  	}
  }
  /*-----------------------------------------------------------*/
  
  