FreeRTOS-Kernel/FreeRTOS/Demo/Common/Minimal/flash_timer.c

/*
 * FreeRTOS V202112.00
 * 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.
 *
 * https://www.FreeRTOS.org
 * https://github.com/FreeRTOS
 *
 */

/**
 * Repeatedly toggles one or more LEDs using software timers - one timer per
 * LED.
 */

/* Scheduler include files. */
#include "FreeRTOS.h"
#include "timers.h"

/* Demo program include files. */
#include "partest.h"
#include "flash_timer.h"

/* The toggle rates are all a multple of ledFLASH_RATE_BASE. */
#define ledFLASH_RATE_BASE    ( ( ( TickType_t ) 333 ) / portTICK_PERIOD_MS )

/* A block time of zero simple means "don't block". */
#define ledDONT_BLOCK         ( ( TickType_t ) 0 )

/*-----------------------------------------------------------*/

/*
 * The callback function used by each LED flashing timer.  All the timers use
 * this function, and the timer ID is used within the function to determine
 * which timer has actually expired.
 */
static void prvLEDTimerCallback( TimerHandle_t xTimer );

/*-----------------------------------------------------------*/

void vStartLEDFlashTimers( UBaseType_t uxNumberOfLEDs )
{
    UBaseType_t uxLEDTimer;
    TimerHandle_t xTimer;

    /* Create and start the requested number of timers. */
    for( uxLEDTimer = 0; uxLEDTimer < uxNumberOfLEDs; ++uxLEDTimer )
    {
        /* Create the timer. */
        xTimer = xTimerCreate( "Flasher",                               /* A text name, purely to help debugging. */
                               ledFLASH_RATE_BASE * ( uxLEDTimer + 1 ), /* The timer period, which is a multiple of ledFLASH_RATE_BASE. */
                               pdTRUE,                                  /* This is an auto-reload timer, so xAutoReload is set to pdTRUE. */
                               ( void * ) uxLEDTimer,                   /* The ID is used to identify the timer within the timer callback function, as each timer uses the same callback. */
                               prvLEDTimerCallback                      /* Each timer uses the same callback. */
                               );

        /* If the timer was created successfully, attempt to start it.  If the
         * scheduler has not yet been started then the timer command queue must
         * be long enough to hold each command sent to it until such time that the
         * scheduler is started.  The timer command queue length is set by
         * configTIMER_QUEUE_LENGTH in FreeRTOSConfig.h. */
        if( xTimer != NULL )
        {
            xTimerStart( xTimer, ledDONT_BLOCK );
        }
    }
}
/*-----------------------------------------------------------*/

static void prvLEDTimerCallback( TimerHandle_t xTimer )
{
    BaseType_t xTimerID;

    /* The timer ID is used to identify the timer that has actually expired as
     * each timer uses the same callback.  The ID is then also used as the number
     * of the LED that is to be toggled. */
    xTimerID = ( BaseType_t ) pvTimerGetTimerID( xTimer );
    vParTestToggleLED( xTimerID );
}