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/*
FreeRTOS V7.3.0 - Copyright (C) 2012 Real Time Engineers Ltd.
FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME. PLEASE VISIT
http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* 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 versions, 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.
*/
/**
* This is a very simple queue test. See the BlockQ. c documentation for a more
* comprehensive version.
*
* Creates two tasks that communicate over a single queue. One task acts as a
* producer, the other a consumer.
*
* The producer loops for three iteration, posting an incrementing number onto the
* queue each cycle. It then delays for a fixed period before doing exactly the
* same again.
*
* The consumer loops emptying the queue. Each item removed from the queue is
* checked to ensure it contains the expected value. When the queue is empty it
* blocks for a fixed period, then does the same again.
*
* All queue access is performed without blocking. The consumer completely empties
* the queue each time it runs so the producer should never find the queue full.
*
* An error is flagged if the consumer obtains an unexpected value or the producer
* find the queue is full.
*
* \page PollQC pollQ.c
* \ingroup DemoFiles
* <HR>
*/
/*
Changes from V2.0.0
+ Delay periods are now specified using variables and constants of
portTickType rather than unsigned long.
*/
#include <stdlib.h>
/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"
#include "print.h"
/* Demo program include files. */
#include "PollQ.h"
#define pollqSTACK_SIZE ( ( unsigned short ) configMINIMAL_STACK_SIZE )
/* The task that posts the incrementing number onto the queue. */
static void vPolledQueueProducer( void *pvParameters );
/* The task that empties the queue. */
static void vPolledQueueConsumer( void *pvParameters );
/* Variables that are used to check that the tasks are still running with no errors. */
static volatile short sPollingConsumerCount = 0, sPollingProducerCount = 0;
/*-----------------------------------------------------------*/
void vStartPolledQueueTasks( unsigned portBASE_TYPE uxPriority )
{
static xQueueHandle xPolledQueue;
const unsigned portBASE_TYPE uxQueueSize = 10;
/* Create the queue used by the producer and consumer. */
xPolledQueue = xQueueCreate( uxQueueSize, ( unsigned portBASE_TYPE ) sizeof( unsigned short ) );
/* Spawn the producer and consumer. */
xTaskCreate( vPolledQueueConsumer, "QConsNB", pollqSTACK_SIZE, ( void * ) &xPolledQueue, uxPriority, NULL );
xTaskCreate( vPolledQueueProducer, "QProdNB", pollqSTACK_SIZE, ( void * ) &xPolledQueue, uxPriority, NULL );
}
/*-----------------------------------------------------------*/
static void vPolledQueueProducer( void *pvParameters )
{
unsigned short usValue = 0, usLoop;
xQueueHandle *pxQueue;
const portTickType xDelay = ( portTickType ) 200 / portTICK_RATE_MS;
const unsigned short usNumToProduce = 3;
const char * const pcTaskStartMsg = "Polled queue producer started.\r\n";
const char * const pcTaskErrorMsg = "Could not post on polled queue.\r\n";
short sError = pdFALSE;
/* Queue a message for printing to say the task has started. */
vPrintDisplayMessage( &pcTaskStartMsg );
/* The queue being used is passed in as the parameter. */
pxQueue = ( xQueueHandle * ) pvParameters;
for( ;; )
{
for( usLoop = 0; usLoop < usNumToProduce; ++usLoop )
{
/* Send an incrementing number on the queue without blocking. */
if( xQueueSendToBack( *pxQueue, ( void * ) &usValue, ( portTickType ) 0 ) != pdPASS )
{
/* We should never find the queue full - this is an error. */
vPrintDisplayMessage( &pcTaskErrorMsg );
sError = pdTRUE;
}
else
{
if( sError == pdFALSE )
{
/* If an error has ever been recorded we stop incrementing the
check variable. */
++sPollingProducerCount;
}
/* Update the value we are going to post next time around. */
++usValue;
}
}
/* Wait before we start posting again to ensure the consumer runs and
empties the queue. */
vTaskDelay( xDelay );
}
}
/*-----------------------------------------------------------*/
static void vPolledQueueConsumer( void *pvParameters )
{
unsigned short usData, usExpectedValue = 0;
xQueueHandle *pxQueue;
const portTickType xDelay = ( portTickType ) 200 / portTICK_RATE_MS;
const char * const pcTaskStartMsg = "Polled queue consumer started.\r\n";
const char * const pcTaskErrorMsg = "Incorrect value received on polled queue.\r\n";
short sError = pdFALSE;
/* Queue a message for printing to say the task has started. */
vPrintDisplayMessage( &pcTaskStartMsg );
/* The queue being used is passed in as the parameter. */
pxQueue = ( xQueueHandle * ) pvParameters;
for( ;; )
{
/* Loop until the queue is empty. */
while( uxQueueMessagesWaiting( *pxQueue ) )
{
if( xQueueReceive( *pxQueue, &usData, ( portTickType ) 0 ) == pdPASS )
{
if( usData != usExpectedValue )
{
/* This is not what we expected to receive so an error has
occurred. */
vPrintDisplayMessage( &pcTaskErrorMsg );
sError = pdTRUE;
/* Catch-up to the value we received so our next expected value
should again be correct. */
usExpectedValue = usData;
}
else
{
if( sError == pdFALSE )
{
/* Only increment the check variable if no errors have
occurred. */
++sPollingConsumerCount;
}
}
++usExpectedValue;
}
}
/* Now the queue is empty we block, allowing the producer to place more
items in the queue. */
vTaskDelay( xDelay );
}
}
/*-----------------------------------------------------------*/
/* This is called to check that all the created tasks are still running with no errors. */
portBASE_TYPE xArePollingQueuesStillRunning( void )
{
static short sLastPollingConsumerCount = 0, sLastPollingProducerCount = 0;
portBASE_TYPE xReturn;
if( ( sLastPollingConsumerCount == sPollingConsumerCount ) ||
( sLastPollingProducerCount == sPollingProducerCount )
)
{
xReturn = pdFALSE;
}
else
{
xReturn = pdTRUE;
}
sLastPollingConsumerCount = sPollingConsumerCount;
sLastPollingProducerCount = sPollingProducerCount;
return xReturn;
}
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