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/*
FreeRTOS.org V5.1.2 - Copyright (C) 2003-2009 Richard Barry.
This file is part of the FreeRTOS.org distribution.
FreeRTOS.org is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
FreeRTOS.org 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
along with FreeRTOS.org; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
A special exception to the GPL can be applied should you wish to distribute
a combined work that includes FreeRTOS.org, without being obliged to provide
the source code for any proprietary components. See the licensing section
of http://www.FreeRTOS.org for full details of how and when the exception
can be applied.
***************************************************************************
***************************************************************************
* *
* Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation *
* *
* This is a concise, step by step, 'hands on' guide that describes both *
* general multitasking concepts and FreeRTOS specifics. It presents and *
* explains numerous examples that are written using the FreeRTOS API. *
* Full source code for all the examples is provided in an accompanying *
* .zip file. *
* *
***************************************************************************
***************************************************************************
Please ensure to read the configuration and relevant port sections of the
online documentation.
http://www.FreeRTOS.org - Documentation, latest information, license and
contact details.
http://www.SafeRTOS.com - A version that is certified for use in safety
critical systems.
http://www.OpenRTOS.com - Commercial support, development, porting,
licensing and training services.
*/
/**
* Defines the tasks and co-routines used to toggle the segments of the two
* seven segment displays, as described at the top of main.c
*/
#include <stdlib.h>
/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
#include "croutine.h"
/* Demo program include files. */
#include "partest.h"
/*-----------------------------------------------------------*/
/* One task per segment of the left side display. */
#define ledNUM_OF_LED_TASKS ( 7 )
/* Each task toggles at a frequency that is a multiple of 333ms. */
#define ledFLASH_RATE_BASE ( ( portTickType ) 333 )
/* One co-routine per segment of the right hand display. */
#define ledNUM_OF_LED_CO_ROUTINES 7
/* All co-routines run at the same priority. */
#define ledCO_ROUTINE_PRIORITY 0
/*-----------------------------------------------------------*/
/* The task that is created 7 times. */
static void vLEDFlashTask( void *pvParameters );
/* The co-routine that is created 7 times. */
static void prvFixedDelayCoRoutine( xCoRoutineHandle xHandle, unsigned short usIndex );
/* This task is created once, but itself creates 7 co-routines. */
static void vLEDCoRoutineControlTask( void *pvParameters );
/* Handles to each of the 7 tasks. Used so the tasks can be suspended
and resumed. */
static xTaskHandle xFlashTaskHandles[ ledNUM_OF_LED_TASKS ] = { 0 };
/* Handle to the task in which the co-routines run. Used so the
co-routines can be suspended and resumed. */
static xTaskHandle xCoroutineTask;
/*-----------------------------------------------------------*/
/**
* Creates the tasks and co-routines used to toggle the segments of the two
* seven segment displays, as described at the top of main.c
*/
void vCreateFlashTasksAndCoRoutines( void )
{
signed short sLEDTask;
/* Create the tasks that flash segments on the first LED. */
for( sLEDTask = 0; sLEDTask < ledNUM_OF_LED_TASKS; ++sLEDTask )
{
/* Spawn the task. */
xTaskCreate( vLEDFlashTask, ( signed char * ) "LEDt", configMINIMAL_STACK_SIZE, ( void * ) sLEDTask, ( tskIDLE_PRIORITY + 1 ), &( xFlashTaskHandles[ sLEDTask ] ) );
}
/* Create the task in which the co-routines run. The co-routines themselves
are created within the task. */
xTaskCreate( vLEDCoRoutineControlTask, ( signed char * ) "LEDc", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY, &xCoroutineTask );
}
/*-----------------------------------------------------------*/
void vSuspendFlashTasks( unsigned char ucIndex, short sSuspendTasks )
{
short sLEDTask;
if( ucIndex == configLEFT_DISPLAY )
{
/* Suspend or resume the tasks that are toggling the segments of the
left side display. */
for( sLEDTask = 0; sLEDTask < ledNUM_OF_LED_TASKS; ++sLEDTask )
{
if( xFlashTaskHandles[ sLEDTask ] != NULL )
{
if( sSuspendTasks == pdTRUE )
{
vTaskSuspend( xFlashTaskHandles[ sLEDTask ] );
}
else
{
vTaskResume( xFlashTaskHandles[ sLEDTask ] );
}
}
}
}
else
{
/* Suspend or resume the task in which the co-routines are running. The
co-routines toggle the segments of the right side display. */
if( sSuspendTasks == pdTRUE )
{
vTaskSuspend( xCoroutineTask );
}
else
{
vTaskResume( xCoroutineTask );
}
}
}
/*-----------------------------------------------------------*/
static void vLEDFlashTask( void * pvParameters )
{
portTickType xFlashRate, xLastFlashTime;
unsigned short usLED;
/* The LED to flash is passed in as the task parameter. */
usLED = ( unsigned short ) pvParameters;
/* Calculate the rate at which this task is going to toggle its LED. */
xFlashRate = ledFLASH_RATE_BASE + ( ledFLASH_RATE_BASE * ( portTickType ) usLED );
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( usLED );
/* Delay for half the flash period then turn the LED off. */
vTaskDelayUntil( &xLastFlashTime, xFlashRate );
vParTestToggleLED( usLED );
}
}
/*-----------------------------------------------------------*/
static void vLEDCoRoutineControlTask( void *pvParameters )
{
unsigned short usCoroutine;
( void ) pvParameters;
/* Create the co-routines - one of each segment of the right side display. */
for( usCoroutine = 0; usCoroutine < ledNUM_OF_LED_CO_ROUTINES; usCoroutine++ )
{
xCoRoutineCreate( prvFixedDelayCoRoutine, ledCO_ROUTINE_PRIORITY, usCoroutine );
}
/* This task has nothing else to do except scheduler the co-routines it just
created. */
for( ;; )
{
vCoRoutineSchedule();
}
}
/*-----------------------------------------------------------*/
static void prvFixedDelayCoRoutine( xCoRoutineHandle xHandle, unsigned short usIndex )
{
/* The usIndex parameter of the co-routine function is used as an index into
the xFlashRates array to obtain the delay period to use. */
static const portTickType xFlashRates[ ledNUM_OF_LED_CO_ROUTINES ] = { 150 / portTICK_RATE_MS,
300 / portTICK_RATE_MS,
450 / portTICK_RATE_MS,
600 / portTICK_RATE_MS,
750 / portTICK_RATE_MS,
900 / portTICK_RATE_MS,
1050 / portTICK_RATE_MS };
/* Co-routines MUST start with a call to crSTART. */
crSTART( xHandle );
for( ;; )
{
/* Toggle the LED. An offset of 8 is used to skip over the segments of
the left side display which use the low numbers. */
vParTestToggleLED( usIndex + 8 );
/* Delay until it is time to toggle the segment that this co-routine is
controlling again. */
crDELAY( xHandle, xFlashRates[ usIndex ] );
}
/* Co-routines MUST end with a call to crEND. */
crEND();
}
/*-----------------------------------------------------------*/
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