main.c

FreeRTOS source code as bundled with the book "Using FreeRTOS Real-Time Kernel - A Practical Approac

/*
	FreeRTOS.org V5.0.4 - Copyright (C) 2003-2008 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.

    ***************************************************************************
    ***************************************************************************
    *                                                                         *
    * SAVE TIME AND MONEY!  We can port FreeRTOS.org to your own hardware,    *
    * and even write all or part of your application on your behalf.          *
    * See http://www.OpenRTOS.com for details of the services we provide to   *
    * expedite your project.                                                  *
    *                                                                         *
    ***************************************************************************
    ***************************************************************************

	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.
*/

/* FreeRTOS.org includes. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

/* Demo includes. */
#include "basic_io.h"


/* The tasks to be created.  Two instances are created of the sender task while
only a single instance is created of the receiver task. */
static void vSenderTask( void *pvParameters );
static void vReceiverTask( void *pvParameters );

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

/* Declare a variable of type xQueueHandle.  This is used to store the queue
that is accessed by all three tasks. */
xQueueHandle xQueue;


int main( void )
{
    /* The queue is created to hold a maximum of 5 long values. */
    xQueue = xQueueCreate( 5, sizeof( long ) );

	if( xQueue != NULL )
	{
		/* Create two instances of the task that will write to the queue.  The
		parameter is used to pass the value that the task should write to the queue,
		so one task will continuously write 100 to the queue while the other task 
		will continuously write 200 to the queue.  Both tasks are created at
		priority 1. */
		xTaskCreate( vSenderTask, "Sender1", 1000, ( void * ) 100, 1, NULL );
		xTaskCreate( vSenderTask, "Sender2", 1000, ( void * ) 200, 1, NULL );

		/* Create the task that will read from the queue.  The task is created with
		priority 2, so above the priority of the sender tasks. */
		xTaskCreate( vReceiverTask, "Receiver", 1000, NULL, 2, NULL );

		/* Start the scheduler so the created tasks start executing. */
		vTaskStartScheduler();
	}
	else
	{
		/* The queue could not be created. */
	}
		
    /* If all is well we will never reach here as the scheduler will now be
    running the tasks.  If we do reach here then it is likely that there was 
    insufficient heap memory available for a resource to be created. */
	for( ;; );
	return 0;
}
/*-----------------------------------------------------------*/

static void vSenderTask( void *pvParameters )
{
long lValueToSend;
portBASE_TYPE xStatus;

	/* Two instances are created of this task so the value that is sent to the
	queue is passed in via the task parameter rather than be hard coded.  This way
	each instance can use a different value.  Cast the parameter to the required
	type. */
	lValueToSend = ( long ) pvParameters;

	/* As per most tasks, this task is implemented within an infinite loop. */
	for( ;; )
	{
		/* The first parameter is the queue to which data is being sent.  The 
		queue was created before the scheduler was started, so before this task
		started to execute.

		The second parameter is the address of the data to be sent.

		The third parameter is the Block time