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/*
FreeRTOS V7.2.0 - Copyright (C) 2012 Real Time Engineers Ltd.
***************************************************************************
* *
* FreeRTOS tutorial books are available in pdf and paperback. *
* Complete, revised, and edited pdf reference manuals are also *
* available. *
* *
* Purchasing FreeRTOS documentation will not only help you, by *
* ensuring you get running as quickly as possible and with an *
* in-depth knowledge of how to use FreeRTOS, it will also help *
* the FreeRTOS project to continue with its mission of providing *
* professional grade, cross platform, de facto standard solutions *
* for microcontrollers - completely free of charge! *
* *
* >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
* *
* Thank you for using FreeRTOS, and thank you for your support! *
* *
***************************************************************************
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. 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!
***************************************************************************
* *
* 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, training, latest information,
license and contact details.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool.
Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell
the code with commercial support, indemnification, and middleware, under
the OpenRTOS brand: http://www.OpenRTOS.com. High Integrity Systems also
provide a safety engineered and independently SIL3 certified version under
the SafeRTOS brand: http://www.SafeRTOS.com.
*/
/**
* Creates eight tasks, each of which flash an LED at a different rate. The first
* LED flashes every 125ms, the second every 250ms, the third every 375ms, etc.
*
* The LED flash tasks provide instant visual feedback. They show that the scheduler
* is still operational.
*
* The PC port uses the standard parallel port for outputs, the Flashlite 186 port
* uses IO port F.
*
* \page flashC flash.c
* \ingroup DemoFiles
* <HR>
*/
/*
Changes from V2.0.0
+ Delay periods are now specified using variables and constants of
portTickType rather than unsigned long.
Changes from V2.1.1
+ The stack size now uses configMINIMAL_STACK_SIZE.
+ String constants made file scope to decrease stack depth on 8051 port.
*/
#include <stdlib.h>
/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
/* Demo program include files. */
#include "partest.h"
#include "flash.h"
#include "print.h"
#define ledSTACK_SIZE configMINIMAL_STACK_SIZE
/* Structure used to pass parameters to the LED tasks. */
typedef struct LED_PARAMETERS
{
unsigned portBASE_TYPE uxLED; /*< The output the task should use. */
portTickType xFlashRate; /*< The rate at which the LED should flash. */
} xLEDParameters;
/* The task that is created eight times - each time with a different xLEDParaemtes
structure passed in as the parameter. */
static void vLEDFlashTask( void *pvParameters );
/* String to print if USE_STDIO is defined. */
const char * const pcTaskStartMsg = "LED flash task started.\r\n";
/*-----------------------------------------------------------*/
void vStartLEDFlashTasks( unsigned portBASE_TYPE uxPriority )
{
unsigned portBASE_TYPE uxLEDTask;
xLEDParameters *pxLEDParameters;
const unsigned portBASE_TYPE uxNumOfLEDs = 8;
const portTickType xFlashRate = 125;
/* Create the eight tasks. */
for( uxLEDTask = 0; uxLEDTask < uxNumOfLEDs; ++uxLEDTask )
{
/* Create and complete the structure used to pass parameters to the next
created task. */
pxLEDParameters = ( xLEDParameters * ) pvPortMalloc( sizeof( xLEDParameters ) );
pxLEDParameters->uxLED = uxLEDTask;
pxLEDParameters->xFlashRate = ( xFlashRate + ( xFlashRate * ( portTickType ) uxLEDTask ) );
pxLEDParameters->xFlashRate /= portTICK_RATE_MS;
/* Spawn the task. */
xTaskCreate( vLEDFlashTask, "LEDx", ledSTACK_SIZE, ( void * ) pxLEDParameters, uxPriority, ( xTaskHandle * ) NULL );
}
}
/*-----------------------------------------------------------*/
static void vLEDFlashTask( void *pvParameters )
{
xLEDParameters *pxParameters;
/* Queue a message for printing to say the task has started. */
vPrintDisplayMessage( &pcTaskStartMsg );
pxParameters = ( xLEDParameters * ) pvParameters;
for(;;)
{
/* Delay for half the flash period then turn the LED on. */
vTaskDelay( pxParameters->xFlashRate / ( portTickType ) 2 );
vParTestToggleLED( pxParameters->uxLED );
/* Delay for half the flash period then turn the LED off. */
vTaskDelay( pxParameters->xFlashRate / ( portTickType ) 2 );
vParTestToggleLED( pxParameters->uxLED );
}
}
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