@ -1,38 +1,44 @@
/*
FreeRTOS V6 .1 .1 - Copyright ( C ) 2011 Real Time Engineers Ltd .
FreeRTOS V7 .0 .0 - Copyright ( C ) 2011 Real Time Engineers Ltd .
FreeRTOS supports many tools and architectures . V7 .0 .0 is sponsored by :
Atollic AB - Atollic provides professional embedded systems development
tools for C / C + + development , code analysis and test automation .
See http : //www.atollic.com
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* *
* If you are : *
* *
* + New to FreeRTOS , *
* + Wanting to learn FreeRTOS or multitasking in general quickly *
* + Looking for basic training , *
* + Wanting to improve your FreeRTOS skills and productivity *
* FreeRTOS tutorial books are available in pdf and paperback . *
* Complete , revised , and edited pdf reference manuals are also *
* available . *
* *
* then take a look at the FreeRTOS books - available as PDF or paperback *
* 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 ! *
* *
* " Using the FreeRTOS Real Time Kernel - a Practical Guide " *
* http : //www.FreeRTOS.org/Documentation *
* > > > See http : //www.FreeRTOS.org/Documentation for details. <<< *
* *
* A pdf reference manual is also available . Both are usually delivered *
* to your inbox within 20 minutes to two hours when purchased between 8 am *
* and 8 pm GMT ( although please allow up to 24 hours in case of *
* exceptional circumstances ) . Thank you for your support ! *
* 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 excep tion to the GPL is included to allow you to distribute
combined work that includes FreeRTOS without being obliged to provide the
code for proprietary components outside of the FreeRTOS kernel .
is distributed in the hope that it will be useful , but WITHOUT
WARRANTY ; without even the implied warranty of MERCHANTABILITY or
FOR A PARTICULAR PURPOSE . See the GNU General Public License for
>> > NOTE < < < The modifica tion 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
@ -52,55 +58,80 @@
*/
/*
* This simple demo project runs on the STM32 Discovery board , which is
* populated with an STM32F100RB Cortex - M3 microcontroller . The discovery board
* makes an ideal low cost evaluation platform , but the 8 K of RAM provided on the
* STM32F100RB does not allow the simple application to demonstrate all of all the
* FreeRTOS kernel features . Therefore , this simple demo only actively
* demonstrates task , queue , timer and interrupt functionality . In addition , the
* demo is configured to include malloc failure , idle and stack overflow hook
* functions .
*
* The idle hook function :
* The idle hook function queries the amount of FreeRTOS heap space that is
* remaining ( see vApplicationIdleHook ( ) defined in this file ) . The demo
* application is configured use 7 K or the available 8 K of RAM as the FreeRTOS heap .
* Memory is only allocated from this heap during initialisation , and this demo
* only actually uses 1.6 K bytes of the configured 7 K available - leaving 5.4 K
* bytes of heap space unallocated .
*
* The main ( ) Function :
* main ( ) creates one software timer , one queue , and two tasks . It then starts the
* scheduler .
*
* The Queue Send Task :
* The queue send task is implemented by the prvQueueSendTask ( ) function in this
* file . prvQueueSendTask ( ) sits in a loop that causes it to repeatedly block for
* 200 milliseconds , before sending the value 100 to the queue that was created
* within main ( ) . Once the value is sent , the task loops back around to block for
* another 200 milliseconds .
*
* The Queue Receive Task :
* The queue receive task is implemented by the prvQueueReceiveTask ( ) function
* in this file . prvQueueReceiveTask ( ) sits in a loop that causes repeatedly
* attempt to read data from the queue that was created within main ( ) . When data
* is received , the task checks the value of the data , and if the value equals
* the expected 100 , toggles the green LED . The ' block time ' parameter passed to
* the queue receive function specifies that the task should be held in the Blocked
* state indefinitely to wait for data to be available on the queue . The queue
* receive task will only leave the Blocked state when the queue send task writes
* to the queue . As the queue send task writes to the queue every 200
* milliseconds , the queue receive task leaves the Blocked state every 200
* milliseconds , and therefore toggles the green LED every 200 milliseconds .
*
* The LED Software Timer and the Button Interrupt :
* The user button B1 is configured to generate an interrupt each time it is
* pressed . The interrupt service routine switches the red LED on , and resets the
* LED software timer . The LED timer has a 5000 millisecond ( 5 second ) period , and
* uses a callback function that is defined to just turn the red LED off .
* Therefore , pressing the user button will turn the red LED on , and the LED will
* remain on until a full five seconds pass without the button being pressed .
*/
* main - blinky . c is included when the " Blinky " build configuration is used .
* main - full . c is included when the " Full " build configuration is used .
*
* main - full . c ( this file ) defines a comprehensive demo that creates many
* tasks , queues , semaphores and timers . It also demonstrates how Cortex - M3
* interrupts can interact with FreeRTOS tasks / timers , and implements a simple
* and small interactive web server .
*
* This project runs on the SmartFusion A2F - EVAL - KIT evaluation board , which
* is populated with an A2F200M3F SmartFusion mixed signal FPGA . The A2F200M3F
* incorporates a Cortex - M3 microcontroller .
*
* The main ( ) Function :
* main ( ) creates two demo specific software timers , one demo specific queue ,
* and two demo specific tasks . It then creates a whole host of ' standard demo '
* tasks / queues / semaphores , before starting the scheduler . The demo specific
* tasks and timers are described in the comments here . The standard demo
* tasks are described on the FreeRTOS . org web site .
*
* The standard demo tasks provide no specific functionality . They are
* included to both test the FreeRTOS port , and provide examples of how the
* various FreeRTOS API functions can be used .
*
* The Demo Specific Queue Send Task :
* The queue send task is implemented by the prvQueueSendTask ( ) function in
* this file . prvQueueSendTask ( ) sits in a loop that causes it to repeatedly
* block for 200 milliseconds , before sending the value 100 to the queue that
* was created within main ( ) . Once the value is sent , the task loops back
* around to block for another 200 milliseconds .
*
* The Demo Specific Queue Receive Task :
* The queue receive task is implemented by the prvQueueReceiveTask ( ) function
* in this file . prvQueueReceiveTask ( ) sits in a loop that causes it to
* repeatedly attempt to read data from the queue that was created within
* main ( ) . When data is received , the task checks the value of the data , and
* if the value equals the expected 100 , toggles the green LED . The ' block
* time ' parameter passed to the queue receive function specifies that the task
* should be held in the Blocked state indefinitely to wait for data to be
* available on the queue . The queue receive task will only leave the Blocked
* state when the queue send task writes to the queue . As the queue send task
* writes to the queue every 200 milliseconds , the queue receive task leaves
* the Blocked state every 200 milliseconds , and therefore toggles the LED
* every 200 milliseconds .
*
* The Demo Specific LED Software Timer and the Button Interrupt :
* The user button SW1 is configured to generate an interrupt each time it is
* pressed . The interrupt service routine switches an LED on , and resets the
* LED software timer . The LED timer has a 5000 millisecond ( 5 second ) period ,
* and uses a callback function that is defined to just turn the LED off again .
* Therefore , pressing the user button will turn the LED on , and the LED will
* remain on until a full five seconds pass without the button being pressed .
*
* The Demo Specific Idle Hook Function :
* The idle hook function demonstrates how to query the amount of FreeRTOS heap
* space that is remaining ( see vApplicationIdleHook ( ) defined in this file ) .
*
* The Demo Specific " Check " Callback Function :
* This is called each time the ' check ' timer expires . The check timer
* callback function inspects all the standard demo tasks to see if they are
* all executing as expected . The check timer is initially configured to
* expire every three seconds , but will shorted this to every 500 ms if an error
* is ever discovered . The check timer callback toggles the LED defined by
* the mainCHECK_LED definition each time it executes . Therefore , if LED
* mainCHECK_LED is toggling every three seconds , then no error have been found .
* If LED mainCHECK_LED is toggling every 500 ms , then at least one error has
* been found . The task in which the error was discovered is displayed at the
* bottom of the " task stats " page that is served by the embedded web server .
*
* The Web Server Task :
* The IP address used by the SmartFusion target is configured by the
* definitions configIP_ADDR0 to configIP_ADDR3 , which are located in the
* FreeRTOSConfig . h header file . See the documentation page for this example
* on the http : //www.FreeRTOS.org web site for further connection information.
*/
/* Kernel includes. */
# include "FreeRTOS.h"
@ -138,12 +169,19 @@ will remove items as they are added, meaning the send task should always find
the queue empty . */
# define mainQUEUE_LENGTH ( 1 )
/* The LED toggled by the check timer callback function. */
# define mainCHECK_LED 0x07UL
/* The LED turned on by the button interrupt, and turned off by the LED timer. */
# define mainTIMER_CONTROLLED_LED 0x06UL
/* The LED toggle by the queue receive task. */
# define mainTASK_CONTROLLED_LED 0x05UL
/* Constant used by the standard timer test functions. */
# define mainTIMER_TEST_PERIOD ( 50 )
/* Priorities used by the various different tasks. */
# define mainCHECK_TASK_PRIORITY ( configMAX_PRIORITIES - 1 )
# define mainQUEUE_POLL_PRIORITY ( tskIDLE_PRIORITY + 1 )
# define mainSEM_TEST_PRIORITY ( tskIDLE_PRIORITY + 1 )
@ -158,6 +196,16 @@ the queue empty. */
stack than most of the other tasks . */
# define mainuIP_STACK_SIZE ( configMINIMAL_STACK_SIZE * 3 )
/* The period at which the check timer will expire, in ms, provided no errors
have been reported by any of the standard demo tasks . */
# define mainCHECK_TIMER_PERIOD_ms ( 3000UL )
/* The period at which the check timer will expire, in ms, if an error has been
reported in one of the standard demo tasks . */
# define mainERROR_CHECK_TIMER_PERIOD_ms ( 500UL )
/* A zero block time. */
# define mainDONT_BLOCK ( 0UL )
/*-----------------------------------------------------------*/
/*
@ -177,11 +225,14 @@ static void prvQueueSendTask( void *pvParameters );
*/
static void vLEDTimerCallback ( xTimerHandle xTimer ) ;
/*
* The check timer callback function , as described at the top of this file .
*/
static void vCheckTimerCallback ( xTimerHandle xTimer ) ;
/*
* This is not a ' standard ' partest function , so the prototype is not in
* partest . h
* partest . h , and is instead included here .
*/
void vParTestSetLEDFromISR ( unsigned portBASE_TYPE uxLED , signed portBASE_TYPE xValue ) ;
@ -192,18 +243,20 @@ extern void vuIP_Task( void *pvParameters );
/*-----------------------------------------------------------*/
/* The queue used by both tasks. */
/* The queue used by both application specific demo tasks defined in this file . */
static xQueueHandle xQueue = NULL ;
/* The LED software timer. This uses vLEDTimerCallback() as it s callback
/* The LED software timer. This uses vLEDTimerCallback() as it ' s callback
function . */
static xTimerHandle xLEDTimer = NULL ;
/* The check timer. This uses vCheckTimerCallback() as it's callback
function . */
static xTimerHandle xCheckTimer = NULL ;
/* The status message that is displayed at the bottom of the "task stats" web
page , which is served by the uIP task . This will report any errors picked up
by the reg test tas k. */
by the check timer callbac k. */
static const char * pcStatusMessage = NULL ;
@ -219,8 +272,8 @@ int main(void)
if ( xQueue ! = NULL )
{
/* Start the two tasks as described in the comments at the top of this
. */
/* Start the two application specific demo tasks, as described in the
comments at the top of this file. */
xTaskCreate ( prvQueueReceiveTask , ( signed char * ) " Rx " , configMINIMAL_STACK_SIZE , NULL , mainQUEUE_RECEIVE_TASK_PRIORITY , NULL ) ;
xTaskCreate ( prvQueueSendTask , ( signed char * ) " TX " , configMINIMAL_STACK_SIZE , NULL , mainQUEUE_SEND_TASK_PRIORITY , NULL ) ;
@ -234,13 +287,16 @@ int main(void)
vLEDTimerCallback /* The callback function that switches the LED off. */
) ;
/* Create the software timer that performs the 'check' functionality,
as described at the top of this file . */
xCheckTimer = xTimerCreate ( ( const signed char * ) " CheckTimer " , /* A text name, purely to help debugging. */
( 3000 / portTICK_RATE_MS ) , /* The timer period, in this case 3000ms (3s). */
( mainCHECK_TIMER_PERIOD_ms / portTICK_RATE_MS ) , /* The timer period, in this case 3000ms (3s). */
pdTRUE , /* This is an auto-reload timer, so xAutoReload is set to pdTRUE. */
( void * ) 0 , /* The ID is not used, so can be set to anything. */
vCheckTimerCallback /* The callback function that inspects the status of all the other tasks. */
) ;
/* Create a lot of 'standard demo' tasks. */
vStartBlockingQueueTasks ( mainBLOCK_Q_PRIORITY ) ;
vCreateBlockTimeTasks ( ) ;
vStartSemaphoreTasks ( mainSEM_TEST_PRIORITY ) ;
@ -250,10 +306,9 @@ int main(void)
vStartRecursiveMutexTasks ( ) ;
vStartTimerDemoTask ( mainTIMER_TEST_PERIOD ) ;
/* T he web server task. */
/* Create t he web server task. */
xTaskCreate ( vuIP_Task , ( signed char * ) " uIP " , mainuIP_STACK_SIZE , NULL , mainuIP_TASK_PRIORITY , NULL ) ;
/* Start the tasks and timer running. */
vTaskStartScheduler ( ) ;
}
@ -269,67 +324,63 @@ int main(void)
static void vCheckTimerCallback ( xTimerHandle xTimer )
{
/* Check the standard demo tasks are running without error. */
/* Check the standard demo tasks are running without error. Latch the
latest reported error in the pcStatusMessage character pointer . */
if ( xAreGenericQueueTasksStillRunning ( ) ! = pdTRUE )
{
/* Increase the rate at which this task cycles, which will increase the
rate at which mainCHECK_LED flashes to give visual feedback that an error
has occurred . */
pcStatusMessage = " Error: GenQueue " ;
// xPrintf( pcStatusMessage );
}
if ( xAreQueuePeekTasksStillRunning ( ) ! = pdTRUE )
{
pcStatusMessage = " Error: QueuePeek \r \n " ;
// xPrintf( pcStatusMessage );
}
if ( xAreBlockingQueuesStillRunning ( ) ! = pdTRUE )
{
pcStatusMessage = " Error: BlockQueue \r \n " ;
// xPrintf( pcStatusMessage );
}
if ( xAreBlockTimeTestTasksStillRunning ( ) ! = pdTRUE )
{
pcStatusMessage = " Error: BlockTime \r \n " ;
// xPrintf( pcStatusMessage );
}
if ( xAreSemaphoreTasksStillRunning ( ) ! = pdTRUE )
{
pcStatusMessage = " Error: SemTest \r \n " ;
// xPrintf( pcStatusMessage );
}
if ( xIsCreateTaskStillRunning ( ) ! = pdTRUE )
{
pcStatusMessage = " Error: Death \r \n " ;
// xPrintf( pcStatusMessage );
}
if ( xAreRecursiveMutexTasksStillRunning ( ) ! = pdTRUE )
{
pcStatusMessage = " Error: RecMutex \r \n " ;
// xPrintf( pcStatusMessage );
}
if ( xAreTimerDemoTasksStillRunning ( ( 3000 / portTICK_RATE_MS ) ) ! = pdTRUE )
if ( xAreTimerDemoTasksStillRunning ( ( mainCHECK_TIMER_PERIOD_ms / portTICK_RATE_MS ) ) ! = pdTRUE )
{
pcStatusMessage = " Error: TimerDemo " ;
}
/* Toggle the check LED to give an indication of the system status. If
the LED toggles every 5 seconds then everything is ok . A faster toggle
an error . */
the LED toggles every mainCHECK_TIMER_PERIOD_ms milliseconds then
everything is ok . A faster toggle indicates an error . */
vParTestToggleLED ( mainCHECK_LED ) ;
/* Have any errors been latch in pcStatusMessage? If so, shorten the
period of the check timer to mainERROR_CHECK_TIMER_PERIOD_ms milliseconds .
This will result in an increase in the rate at which mainCHECK_LED
toggles . */
if ( pcStatusMessage ! = NULL )
{
/* The block time is set to zero as a timer callback must *never*
attempt to block . */
xTimerChangePeriod ( xCheckTimer , ( 500 / portTICK_RATE_MS ) , 0 ) ;
/* This call to xTimerChangePeriod() uses a zero block time. Functions
called from inside of a timer callback function must * never * attempt
to block . */
xTimerChangePeriod ( xCheckTimer , ( mainERROR_CHECK_TIMER_PERIOD_ms / portTICK_RATE_MS ) , mainDONT_BLOCK ) ;
}
}
/*-----------------------------------------------------------*/
@ -337,10 +388,7 @@ static void vCheckTimerCallback( xTimerHandle xTimer )
static void vLEDTimerCallback ( xTimerHandle xTimer )
{
/* The timer has expired - so no button pushes have occurred in the last
five seconds - turn the LED off . NOTE - accessing the LED port should use
a critical section because it is accessed from multiple tasks , and the
button interrupt - in this trivial case , for simplicity , the critical
section is omitted . */
five seconds - turn the LED off . */
vParTestSetLED ( mainTIMER_CONTROLLED_LED , pdFALSE ) ;
}
/*-----------------------------------------------------------*/
@ -377,11 +425,19 @@ static void prvQueueSendTask( void *pvParameters )
portTickType xNextWakeTime ;
const unsigned long ulValueToSend = 100UL ;
/* The suicide tasks must be created last as they need to know how many
/* The suicide tasks must be created last , as they need to know how many
tasks were running prior to their creation in order to ascertain whether
or not the correct / expected number of tasks are running at any given time . */
or not the correct / expected number of tasks are running at any given time .
Therefore the standard demo ' death ' tasks are not created in main ( ) , but
instead created here . */
vCreateSuicidalTasks ( mainCREATOR_TASK_PRIORITY ) ;
/* The check timer command queue will have been filled when the timer test
tasks were created in main ( ) ( this is part of the test they perform ) .
Therefore , while the check timer can be created in main ( ) , it could not be
started from main ( ) . Once the scheduler has started , the timer service
task will have drained the command queue , and now the check task can be
started successfully . */
xTimerStart ( xCheckTimer , portMAX_DELAY ) ;
/* Initialise xNextWakeTime - this only needs to be done once. */
@ -416,13 +472,9 @@ unsigned long ulReceivedValue;
xQueueReceive ( xQueue , & ulReceivedValue , portMAX_DELAY ) ;
/* To get here something must have been received from the queue, but
is it the expected value ? If it is , toggle the green LED. */
is it the expected value ? If it is , toggle the . */
if ( ulReceivedValue = = 100UL )
{
/* NOTE - accessing the LED port should use a critical section
because it is accessed from multiple tasks , and the button interrupt
- in this trivial case , for simplicity , the critical section is
omitted . */
vParTestToggleLED ( mainTASK_CONTROLLED_LED ) ;
}
}
@ -477,7 +529,7 @@ void vApplicationIdleHook( void )
volatile size_t xFreeStackSpace ;
/* This function is called on each cycle of the idle task. In this case it
does nothing useful , other than report the amou t of FreeRTOS heap that
does nothing useful , other than report the amou n t of FreeRTOS heap that
remains unallocated . */
xFreeStackSpace = xPortGetFreeHeapSize ( ) ;
@ -493,9 +545,9 @@ volatile size_t xFreeStackSpace;
char * pcGetTaskStatusMessage ( void )
{
/* Not bothered about a critical section here although technically because of
task priorities the pointer could change it will be atomic if not near
and its not critical . */
/* Not bothered about a critical section here although technically because
of the task priorities the pointer could change it will be atomic if not
near atomic and its not critical . */
if ( pcStatusMessage = = NULL )
{
return " All tasks running without error " ;
Richard Barry
14 years ago