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/*
* FreeRTOS Kernel V10.3.0
* 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!
*/
/**
* 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 ( ( TickType_t ) 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 UBaseType_t uxFlashTaskNumber = 0;
/* The task that is created three times. */
static portTASK_FUNCTION_PROTO( vLEDFlashTask, pvParameters );
/*-----------------------------------------------------------*/
void vStartLEDFlashTasks( UBaseType_t uxPriority )
{
BaseType_t xLEDTask;
/* Create the three tasks. */
for( xLEDTask = 0; xLEDTask < ledNUMBER_OF_LEDS; ++xLEDTask )
{
/* Spawn the task. */
xTaskCreate( vLEDFlashTask, "LEDx", ledSTACK_SIZE, NULL, uxPriority, ( TaskHandle_t * ) NULL );
}
}
/*-----------------------------------------------------------*/
static portTASK_FUNCTION( vLEDFlashTask, pvParameters )
{
TickType_t xFlashRate, xLastFlashTime;
UBaseType_t 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 * ( TickType_t ) uxLED );
xFlashRate /= portTICK_PERIOD_MS;
/* We will turn the LED on and off again in the delay period, so each
delay is only half the total period. */
xFlashRate /= ( TickType_t ) 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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