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/*
FreeRTOS V7.5.1 - Copyright (C) 2013 Real Time Engineers Ltd.
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that has become a de facto standard. *
* *
* Help yourself get started quickly and support the FreeRTOS *
* project by purchasing a FreeRTOS tutorial book, reference *
* manual, or both from: http://www.FreeRTOS.org/Documentation *
* *
* Thank you! *
* *
***************************************************************************
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 modification 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. Full license text is available from the following
link: http://www.freertos.org/a00114.html
1 tab == 4 spaces!
***************************************************************************
* *
* Having a problem? Start by reading the FAQ "My application does *
* not run, what could be wrong?" *
* *
* http://www.FreeRTOS.org/FAQHelp.html *
* *
***************************************************************************
http://www.FreeRTOS.org - Documentation, books, training, latest versions,
license and Real Time Engineers Ltd. contact details.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
compatible FAT file system, and our tiny thread aware UDP/IP stack.
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and middleware.
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
engineered and independently SIL3 certified version for use in safety and
mission critical applications that require provable dependability.
1 tab == 4 spaces!
*/
/**
* This version of flash .c is for use on systems that have limited stack space
* and no display facilities. The complete version can be found in the
* Demo/Common/Full directory.
*
* Three tasks are created, each of which flash an LED at a different rate. The first
* LED flashes every 200ms, the second every 400ms, the third every 600ms.
*
* The LED flash tasks provide instant visual feedback. They show that the scheduler
* is still operational.
*
*/
#include <stdlib.h>
/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
/* Demo program include files. */
#include "partest.h"
#include "flash.h"
#define ledSTACK_SIZE configMINIMAL_STACK_SIZE
#define ledNUMBER_OF_LEDS ( 3 )
#define ledFLASH_RATE_BASE ( ( portTickType ) 333 )
/* Variable used by the created tasks to calculate the LED number to use, and
the rate at which they should flash the LED. */
static volatile unsigned portBASE_TYPE uxFlashTaskNumber = 0;
/* The task that is created three times. */
static portTASK_FUNCTION_PROTO( vLEDFlashTask, pvParameters );
/*-----------------------------------------------------------*/
void vStartLEDFlashTasks( unsigned portBASE_TYPE uxPriority )
{
signed portBASE_TYPE xLEDTask;
/* Create the three tasks. */
for( xLEDTask = 0; xLEDTask < ledNUMBER_OF_LEDS; ++xLEDTask )
{
/* Spawn the task. */
xTaskCreate( vLEDFlashTask, ( signed char * ) "LEDx", ledSTACK_SIZE, NULL, uxPriority, ( xTaskHandle * ) NULL );
}
}
/*-----------------------------------------------------------*/
static portTASK_FUNCTION( vLEDFlashTask, pvParameters )
{
portTickType xFlashRate, xLastFlashTime;
unsigned portBASE_TYPE uxLED;
/* The parameters are not used. */
( void ) pvParameters;
/* Calculate the LED and flash rate. */
portENTER_CRITICAL();
{
/* See which of the eight LED's we should use. */
uxLED = uxFlashTaskNumber;
/* Update so the next task uses the next LED. */
uxFlashTaskNumber++;
}
portEXIT_CRITICAL();
xFlashRate = ledFLASH_RATE_BASE + ( ledFLASH_RATE_BASE * ( portTickType ) uxLED );
xFlashRate /= portTICK_RATE_MS;
/* We will turn the LED on and off again in the delay period, so each
delay is only half the total period. */
xFlashRate /= ( portTickType ) 2;
/* We need to initialise xLastFlashTime prior to the first call to
vTaskDelayUntil(). */
xLastFlashTime = xTaskGetTickCount();
for(;;)
{
/* Delay for half the flash period then turn the LED on. */
vTaskDelayUntil( &xLastFlashTime, xFlashRate );
vParTestToggleLED( uxLED );
/* Delay for half the flash period then turn the LED off. */
vTaskDelayUntil( &xLastFlashTime, xFlashRate );
vParTestToggleLED( uxLED );
}
} /*lint !e715 !e818 !e830 Function definition must be standard for task creation. */
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