path: root/FreeRTOS/Demo/Common/Minimal/TaskNotifyArray.c

/*
 * FreeRTOS V202104.00
 * 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
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 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
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 * 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
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 */


/*
 * Tests the behaviour of arrays of task notifications per task.  The tests in this
 * file are additive to those implemented in FreeRTOS/Demo/Common/Minimal/TaskNotify.c.
 */

/* Standard includes. */
#include <limits.h>

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

/* Demo program include files. */
#include "TaskNotifyArray.h"

#if ( configTASK_NOTIFICATION_ARRAY_ENTRIES < 3 )
    #error This file tests direct to task notification arrays and needs configTASK_NOTIFICATION_ARRAY_ENTRIES to be at least 3.
#endif

/* Allow parameters to be overridden on a demo by demo basis. */
#ifndef notifyNOTIFY_ARRAY_TASK_STACK_SIZE
    #define notifyNOTIFY_ARRAY_TASK_STACK_SIZE    configMINIMAL_STACK_SIZE
#endif

#define notifyTASK_PRIORITY                       ( tskIDLE_PRIORITY )

/* Constants used in tests when setting/clearing bits. */
#define notifyUINT32_MAX                          ( ( uint32_t ) 0xffffffff )
#define notifyUINT32_HIGH_BYTE                    ( ( uint32_t ) 0xff000000 )
#define notifyUINT32_LOW_BYTE                     ( ( uint32_t ) 0x000000ff )

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

/*
 * Implementation of the task that runs the tests - the task runs some tests
 * itself, and others where notifications are sent from a software timer or
 * an interrupt (specifically the tick hook function).
 */
static void prvNotifiedTask( void * pvParameters );

/*
 * Performs the tests that don't require notifications to be sent from a
 * remote source.
 */
static void prvSingleTaskTests( void );

/*
 * Uses a software timer to send notifications to the task while the task is
 * suspended.
 */
static void prvTestNotifyTaskWhileSuspended( void );

/*
 * Uses a software timer to send notifications to the index within the array of
 * task notifications on which the task is blocked.  The task should unblock and
 * the state of all the other task notifications within the array should remain
 * unchanged.
 */
static void prvBlockOnTheNotifiedIndexed( void );

/*
 * As per prvBlockOnTheNotifiedIndexed(), but this time the notification comes from
 * the tick hook function, so from an interrupt rather than from a software timer.
 */
static void prvBlockOnNotificationsComingFromInterrupts( void );

/*
 * As per prvBlockOnTheNotifiedIndexed(), except this time the notification is
 * sent to an index within the task notification array on which the task is not
 * blocked, so this time the task should not unblock and the state of all the
 * task notifications other than the one to which the notification was actually
 * sent should remain unchanged.
 */
static void prvBlockOnANonNotifiedIndexed( void );

/*
 * Callback of the software timer used to send notifications for the
 * prvBlockOnTheNotifiedIndexed() and prvBlockOnANonNotifiedIndexed() tests.
 */
static void prvNotifyingTimerCallback( TimerHandle_t xTimer );

/*
 * Callback for a timer that is used by the prvTestNotifyTaskWhileSuspended()
 * test.
 */
static void prvSuspendedTaskTimerTestCallback( TimerHandle_t xExpiredTimer );

/*
 * Utility function to create pseudo random numbers.
 */
static UBaseType_t prvRand( void );


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

/* Counters used to check the task has not stalled.  ulFineCycleCount is
 * incremented within each test.  ulCourseCycleCounter is incremented one every
 * loop of all the tests to ensure each test is actually executing.  The check task
 * calls xAreTaskNotificationArrayTasksStillRunning() (implemented within this
 * file) to check both counters are changing. */
static volatile uint32_t ulFineCycleCount = 0, ulCourseCycleCounter = 0;

/* The handle of the task that runs the tests and receives the notifications
 * from the software timers and interrupts. */
static TaskHandle_t xTaskToNotify = NULL;

/* The software timers used to send notifications to the main test task. */
static TimerHandle_t xIncrementingIndexTimer = NULL;
static TimerHandle_t xNotifyWhileSuspendedTimer = NULL;

/* Used by the pseudo random number generating function. */
static size_t uxNextRand = 0;

/* Used to communicate when to send a task notification to the tick hook tests. */
static volatile BaseType_t xSendNotificationFromISR = pdFALSE;

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

void vStartTaskNotifyArrayTask( void )
{
    const TickType_t xIncrementingIndexTimerPeriod = pdMS_TO_TICKS( 100 );
    const TickType_t xSuspendTimerPeriod = pdMS_TO_TICKS( 50 );

    /* Create the software timers used for these tests.  The timer callbacks send
     * notifications to this task. */
    xNotifyWhileSuspendedTimer = xTimerCreate( "SingleNotify", xSuspendTimerPeriod, pdFALSE, NULL, prvSuspendedTaskTimerTestCallback );
    xIncrementingIndexTimer = xTimerCreate( "Notifier", xIncrementingIndexTimerPeriod, pdFALSE, NULL, prvNotifyingTimerCallback );
    configASSERT( xNotifyWhileSuspendedTimer );
    configASSERT( xIncrementingIndexTimer );

    /* Create the task that performs some tests by itself, then loops around
     * being notified by both a software timer and an interrupt. */
    xTaskCreate( prvNotifiedTask,                    /* Function that implements the task. */
                 "ArrayNotifed",                     /* Text name for the task - for debugging only - not used by the kernel. */
                 notifyNOTIFY_ARRAY_TASK_STACK_SIZE, /* Task's stack size in words, not bytes!. */
                 NULL,                               /* Task parameter, not used in this case. */
                 notifyTASK_PRIORITY,                /* Task priority, 0 is the lowest. */
                 &xTaskToNotify );                   /* Used to pass a handle to the task out if needed, otherwise set to NULL. */

    /* Pseudo seed the random number generator. */
    uxNextRand = ( size_t ) prvRand;
}
/*-----------------------------------------------------------*/

static void prvNotifiedTask( void * pvParameters )
{
    /* Remove compiler warnings about unused parameters. */
    ( void ) pvParameters;

    /* Loop through each set of test functions in turn.  See the comments above
     * the respective function prototypes above for more details. */
    for( ; ; )
    {
        prvSingleTaskTests();
        prvTestNotifyTaskWhileSuspended();
        prvBlockOnTheNotifiedIndexed();
        prvBlockOnANonNotifiedIndexed();
        prvBlockOnNotificationsComingFromInterrupts();
        ulCourseCycleCounter++;
    }
}
/*-----------------------------------------------------------*/

static void prvSingleTaskTests( void )
{
    const TickType_t xTicksToWait = pdMS_TO_TICKS( 100UL );
    BaseType_t xReturned;
    uint32_t ulNotifiedValue, ulLoop, ulNotifyingValue, ulPreviousValue, ulExpectedValue;
    TickType_t xTimeOnEntering, xTimeNow, xTimeDifference;
    const uint32_t ulFirstNotifiedConst = 100001UL, ulSecondNotifiedValueConst = 5555UL, ulMaxLoops = 5UL;
    const uint32_t ulBit0 = 0x01UL, ulBit1 = 0x02UL;
    UBaseType_t uxIndexToTest, uxOtherIndexes;


    /* ------------------------------------------------------------------------
     * Check blocking when there are no notifications. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* Send notifications to the task notification in each index of the
         * task notification array other than the one on which this task will
         * block. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            if( uxOtherIndexes != uxIndexToTest )
            {
                xTaskNotifyIndexed( xTaskToNotify, uxOtherIndexes, 0, eNoAction );
            }
        }

        xTimeOnEntering = xTaskGetTickCount();
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, notifyUINT32_MAX, 0, &ulNotifiedValue, xTicksToWait );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* Should have blocked for the entire block time. */
        xTimeNow = xTaskGetTickCount();
        xTimeDifference = xTimeNow - xTimeOnEntering;
        configASSERT( xTimeDifference >= xTicksToWait );
        configASSERT( xReturned == pdFAIL );
        configASSERT( ulNotifiedValue == 0UL );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        ( void ) ulNotifiedValue;

        /* Clear all the other notifications within the array of task
         * notifications again ready for the next round. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            if( uxOtherIndexes != uxIndexToTest )
            {
                xReturned = xTaskNotifyStateClearIndexed( xTaskToNotify, uxOtherIndexes );

                /* The notification state was set above so expect it to still be
                 * set. */
                configASSERT( xReturned == pdTRUE );
                ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
            }
        }
    }

    /* ------------------------------------------------------------------------
     * Check no blocking when notifications are pending. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* First notify the task notification at index uxIndexToTest within this
         * task's own array of task notifications - this would not be a normal
         * thing to do and is done here for test purposes only. */
        xReturned = xTaskNotifyAndQueryIndexed( xTaskToNotify, uxIndexToTest, ulFirstNotifiedConst, eSetValueWithoutOverwrite, &ulPreviousValue );

        /* Even through the 'without overwrite' action was used the update should
         * have been successful. */
        configASSERT( xReturned == pdPASS );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* No bits should have been pending previously. */
        configASSERT( ulPreviousValue == 0 );
        ( void ) ulPreviousValue;

        /* The task should now have a notification pending in the task
         * notification at index uxIndexToTest within the task notification array,
         * and so not time out. */
        xTimeOnEntering = xTaskGetTickCount();
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, notifyUINT32_MAX, 0, &ulNotifiedValue, xTicksToWait );
        xTimeNow = xTaskGetTickCount();
        xTimeDifference = xTimeNow - xTimeOnEntering;
        configASSERT( xTimeDifference < xTicksToWait );

        /* The task should have been notified, and the notified value should
         * be equal to ulFirstNotifiedConst. */
        configASSERT( xReturned == pdPASS );
        configASSERT( ulNotifiedValue == ulFirstNotifiedConst );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        ( void ) ulNotifiedValue;
    }

    /*-------------------------------------------------------------------------
     * Check the non-overwriting functionality. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* Send notifications to all indexes with the array of task
         * notifications other than the one on which this task will block. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            if( uxOtherIndexes != uxIndexToTest )
            {
                xReturned = xTaskNotifyIndexed( xTaskToNotify, uxOtherIndexes, ulFirstNotifiedConst, eSetValueWithOverwrite );
                configASSERT( xReturned == pdPASS );
                ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
            }
        }

        /* The notification is performed twice using two different notification
         * values.  The action says don't overwrite so only the first notification
         * should pass and the value read back should also be that used with the
         * first notification. The notification is sent to the task notification at
         * index uxIndexToTest within the array of task notifications. */
        xReturned = xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, ulFirstNotifiedConst, eSetValueWithoutOverwrite );
        configASSERT( xReturned == pdPASS );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        xReturned = xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, ulSecondNotifiedValueConst, eSetValueWithoutOverwrite );
        configASSERT( xReturned == pdFAIL );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* Waiting for the notification should now return immediately so a block
         * time of zero is used. */
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, notifyUINT32_MAX, 0, &ulNotifiedValue, 0 );

        configASSERT( xReturned == pdPASS );
        configASSERT( ulNotifiedValue == ulFirstNotifiedConst );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        ( void ) ulNotifiedValue;

        /* Clear all the other task notifications within the array of task
         * notifications again ready for the next round. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            if( uxOtherIndexes != uxIndexToTest )
            {
                xReturned = xTaskNotifyStateClearIndexed( xTaskToNotify, uxOtherIndexes );
                configASSERT( xReturned == pdTRUE );
                ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

                ulNotifiedValue = ulTaskNotifyValueClearIndexed( xTaskToNotify, uxOtherIndexes, notifyUINT32_MAX );

                /* The notification value was set to ulFirstNotifiedConst in all
                 * the other indexes, so expect it to still have that value. */
                configASSERT( ulNotifiedValue == ulFirstNotifiedConst );
                ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
            }
        }
    }

    /*-------------------------------------------------------------------------
     * Do the same again, only this time use the overwriting version.  This time
     * both notifications should pass, and the value written the second time should
     * overwrite the value written the first time, and so be the value that is read
     * back. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            if( uxOtherIndexes != uxIndexToTest )
            {
                xTaskNotifyIndexed( xTaskToNotify, uxOtherIndexes, ulFirstNotifiedConst, eSetValueWithOverwrite );
            }
        }

        xReturned = xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, ulFirstNotifiedConst, eSetValueWithOverwrite );
        configASSERT( xReturned == pdPASS );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        xReturned = xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, ulSecondNotifiedValueConst, eSetValueWithOverwrite );
        configASSERT( xReturned == pdPASS );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, 0, notifyUINT32_MAX, &ulNotifiedValue, 0 );
        configASSERT( xReturned == pdPASS );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        configASSERT( ulNotifiedValue == ulSecondNotifiedValueConst );
        ( void ) ulNotifiedValue;

        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            if( uxOtherIndexes != uxIndexToTest )
            {
                xReturned = xTaskNotifyStateClearIndexed( xTaskToNotify, uxOtherIndexes );
                configASSERT( xReturned == pdTRUE );
                ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
                ulNotifiedValue = ulTaskNotifyValueClearIndexed( xTaskToNotify, uxOtherIndexes, notifyUINT32_MAX );
                configASSERT( ulNotifiedValue == ulFirstNotifiedConst );
                ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
            }
        }
    }

    /*-------------------------------------------------------------------------
     * For each task notification within the array of task notifications, check
     * notifications with no action pass without updating the value. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* First set the notification values of the task notification at index
         * uxIndexToTest of the array of task notification to
         * ulSecondNotifiedValueConst. */
        xReturned = xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, ulSecondNotifiedValueConst, eSetValueWithOverwrite );
        configASSERT( xReturned == pdPASS );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* Even though ulFirstNotifiedConst is used as the value next, the value
         * read back should remain at ulSecondNotifiedConst as the action is set
         * to eNoAction. */
        xReturned = xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, ulFirstNotifiedConst, eNoAction );
        configASSERT( xReturned == pdPASS );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* All task notifications in the array of task notifications up to and
         * including index uxIndexToTest should still contain the same value. */
        for( uxOtherIndexes = 0; uxOtherIndexes <= uxIndexToTest; uxOtherIndexes++ )
        {
            /* First zero is bits to clear on entry, the second is bits to clear on
             * exist, the last 0 is the block time. */
            xReturned = xTaskNotifyWaitIndexed( uxOtherIndexes, 0, 0, &ulNotifiedValue, 0 );
            configASSERT( ulNotifiedValue == ulSecondNotifiedValueConst );
            ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
        }

        /* All array indexes in the array of task notifications after index
         * uxIndexToTest should still contain 0 as they have not been set in this
         * loop yet.  This time use ulTaskNotifyValueClearIndexed() instead of
         * xTaskNotifyWaitIndexed(), just for test coverage. */
        for( uxOtherIndexes = uxIndexToTest + 1; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            /* This time 0 is the bits to clear parameter - so clearing no bits. */
            ulNotifiedValue = ulTaskNotifyValueClearIndexed( NULL, uxOtherIndexes, 0 );
            configASSERT( ulNotifiedValue == 0 );
            ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
        }
    }

    /*-------------------------------------------------------------------------
     * Check incrementing values.  For each task notification in the array of task
     * notifications in turn, send ulMaxLoop increment notifications, then ensure
     * the received value is as expected - which should be
     * ulSecondNotificationValueConst plus how ever many times to loop iterated. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        for( ulLoop = 0; ulLoop < ulMaxLoops; ulLoop++ )
        {
            /* Increment the value of the task notification at index
             *  uxIndexToTest within the array of task notifications. */
            xReturned = xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, 0, eIncrement );
            configASSERT( xReturned == pdPASS );
            ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        }

        /* All array indexes up to and including uxIndexToTest should still
         * contain the updated value. */
        for( uxOtherIndexes = 0; uxOtherIndexes <= uxIndexToTest; uxOtherIndexes++ )
        {
            /* First zero is bits to clear on entry, the second is bits to clear on
             * exist, the last 0 is the block time. */
            xReturned = xTaskNotifyWaitIndexed( uxOtherIndexes, 0, 0, &ulNotifiedValue, 0 );
            configASSERT( ulNotifiedValue == ( ulSecondNotifiedValueConst + ulMaxLoops ) );
            ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
        }

        /* Should not be any notifications pending now. */
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, 0, 0, &ulNotifiedValue, 0 );
        configASSERT( xReturned == pdFAIL );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        ( void ) ulNotifiedValue;

        /* All notifications values in the array of task notifications after
         * index uxIndexToTest should still contain the un-incremented
         * ulSecondNotifiedValueConst as they have not been set in this loop yet.
         * This time use ulTaskNotifyValueClearIndexed() instead of xTaskNotifyWaitIndexed(),
         * just for test coverage. */
        for( uxOtherIndexes = uxIndexToTest + 1; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            /* This time 0 is the bits to clear parameter - so clearing no bits. */
            ulNotifiedValue = ulTaskNotifyValueClearIndexed( NULL, uxOtherIndexes, 0 );
            configASSERT( ulNotifiedValue == ulSecondNotifiedValueConst );
            ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
        }
    }

    /* Clear all bits ready for next test. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* Start with all bits clear. */
        ulTaskNotifyValueClearIndexed( NULL, uxIndexToTest, notifyUINT32_MAX );
    }

    /*-------------------------------------------------------------------------
     * For each task notification in the array of task notifications in turn, check
     * all bits in the notification's value can be set by notifying the task with
     * one additional bit set on each notification, and exiting the loop when all
     * the bits are found to be set.  As there are 32-bits the loop should execute
     * 32 times before all the bits are found to be set. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        ulNotifyingValue = 0x01;
        ulLoop = 0;

        do
        {
            /* Set the next bit in the value of the task notification at index
             * uxIndexToTest within the array of task notifications. */
            xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, ulNotifyingValue, eSetBits );

            /* Wait for the notified value - which of course will already be
             * available.  Don't clear the bits on entry or exit as this loop is
             * exited when all the bits are set. */
            xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, 0, 0, &ulNotifiedValue, 0 );
            configASSERT( xReturned == pdPASS );
            ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

            ulLoop++;

            /* Use the next bit on the next iteration around this loop. */
            ulNotifyingValue <<= 1UL;
        } while( ulNotifiedValue != notifyUINT32_MAX );

        /* As a 32-bit value was used the loop should have executed 32 times before
         * all the bits were set. */
        configASSERT( ulLoop == 32 );

        /* The value of each task notification within the array of task
         * notifications up to and including index uxIndexToTest should still have
         * all bits set. */
        for( uxOtherIndexes = 0; uxOtherIndexes <= uxIndexToTest; uxOtherIndexes++ )
        {
            /* First zero is bits to clear on entry, the second is bits to clear on
             * exist, the last 0 is the block time. */
            xReturned = xTaskNotifyWaitIndexed( uxOtherIndexes, 0, 0, &ulNotifiedValue, 0 );
            configASSERT( ulNotifiedValue == notifyUINT32_MAX );
            ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
        }

        /* The value of each task notification within the array of task
         *  notifications after index uxIndexToTest should still contain 0 as they
         *  have not been set in this loop yet.  This time use ulTaskNotifyValueClearIndexed()
         *  instead of xTaskNotifyWaitIndexed(), just for test coverage. */
        for( uxOtherIndexes = uxIndexToTest + 1; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            /* This time 0 is the bits to clear parameter - so clearing no bits. */
            ulNotifiedValue = ulTaskNotifyValueClearIndexed( NULL, uxOtherIndexes, 0 );
            configASSERT( ulNotifiedValue == 0 );
            ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
        }
    }

    /*-------------------------------------------------------------------------
     * For each task notification within the array of task notifications in turn,
     * check bits are cleared on entry but not on exit when a notification fails
     * to arrive before timing out - both with and without a timeout value. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* Wait for the notification - but this time it is not given by anything
         * and should return pdFAIL.  The parameters are set to clear bit zero on
         * entry and bit one on exit.  As no notification was received only the bit
         * cleared on entry should actually get cleared. */
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, ulBit0, ulBit1, &ulNotifiedValue, xTicksToWait );
        configASSERT( xReturned == pdFAIL );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* Send a notification with no action to the task notification at index
         * uxIndexToTest within the array of task notifications.  This should not
         * update the bits even though notifyUINT32_MAX is used as the notification
         * value. */
        xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, notifyUINT32_MAX, eNoAction );

        /* All array indexes up to and including uxIndexToTest within the array
         * of task notifications should have the modified value.  */
        for( uxOtherIndexes = 0; uxOtherIndexes <= uxIndexToTest; uxOtherIndexes++ )
        {
            /* Reading back the value should find bit 0 is clear, as this was cleared
             * on entry, but bit 1 is not clear as it will not have been cleared on exit
             * as no notification was received. */
            xReturned = xTaskNotifyWaitIndexed( uxOtherIndexes, 0x00UL, 0x00UL, &ulNotifiedValue, 0 );

            if( uxOtherIndexes == uxIndexToTest )
            {
                /* This is the index being used this time round the loop and its
                 * notification state was set immediately above. */
                configASSERT( xReturned == pdPASS );
            }
            else
            {
                /* Nothing should have set this index's notification state again. */
                configASSERT( xReturned == pdFAIL );
            }

            configASSERT( ulNotifiedValue == ( notifyUINT32_MAX & ~ulBit0 ) );
            ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        }

        /* All array indexes after uxIndexToTest should still contain notifyUINT32_MAX
         * left over from the previous test.  This time use xTaskNotifyValueClear()
         * instead of xTaskNotifyWaitIndexed(), just for test coverage. */
        for( uxOtherIndexes = uxIndexToTest + 1; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            /* This time 0 is the bits to clear parameter - so clearing no bits. */
            ulNotifiedValue = ulTaskNotifyValueClearIndexed( NULL, uxOtherIndexes, 0 );
            configASSERT( ulNotifiedValue == notifyUINT32_MAX );
            ( void ) ulNotifiedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
        }
    }

    /*-------------------------------------------------------------------------
     * Now try clearing the bit on exit. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* The task is notified first using the task notification at index
         * uxIndexToTest within the array of task notifications. */
        xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, 0, eNoAction );
        xTaskNotifyWaitIndexed( uxIndexToTest, 0x00, ulBit1, &ulNotifiedValue, 0 );

        /* However as the bit is cleared on exit, after the returned notification
         * value is set, the returned notification value should not have the bit
         * cleared... */
        configASSERT( ulNotifiedValue == ( notifyUINT32_MAX & ~ulBit0 ) );

        /* ...but reading the value back again should find that the bit was indeed
         * cleared internally.  The returned value should be pdFAIL however as nothing
         * has notified the task in the mean time. */
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, 0x00, 0x00, &ulNotifiedValue, 0 );
        configASSERT( xReturned == pdFAIL );
        configASSERT( ulNotifiedValue == ( notifyUINT32_MAX & ~( ulBit0 | ulBit1 ) ) );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* No other indexes should have a notification pending. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            if( uxOtherIndexes != uxIndexToTest )
            {
                xReturned = xTaskNotifyWaitIndexed( uxOtherIndexes, 0x00UL, 0x00UL, &ulNotifiedValue, 0 );
                configASSERT( xReturned == pdFAIL );
                ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
            }
        }
    }

    /*-------------------------------------------------------------------------
     * For each task notification within the array of task notifications, try
     * querying the previous value while notifying a task. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        xTaskNotifyAndQueryIndexed( xTaskToNotify, uxIndexToTest, 0x00, eSetBits, &ulPreviousValue );
        configASSERT( ulNotifiedValue == ( notifyUINT32_MAX & ~( ulBit0 | ulBit1 ) ) );

        /* Clear all bits. */
        xTaskNotifyWaitIndexed( uxIndexToTest, 0x00, notifyUINT32_MAX, &ulNotifiedValue, 0 );
        xTaskNotifyAndQueryIndexed( xTaskToNotify, uxIndexToTest, 0x00, eSetBits, &ulPreviousValue );
        configASSERT( ulPreviousValue == 0 );

        ulExpectedValue = 0;

        for( ulLoop = 0x01; ulLoop < 0x80UL; ulLoop <<= 1UL )
        {
            /* Set the next bit up, and expect to receive the last bits set (so
             * the previous value will not yet have the bit being set this time
             * around). */
            xTaskNotifyAndQueryIndexed( xTaskToNotify, uxIndexToTest, ulLoop, eSetBits, &ulPreviousValue );
            configASSERT( ulExpectedValue == ulPreviousValue );
            ulExpectedValue |= ulLoop;
        }
    }

    /* ---------------------------------------------------------------------- */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* Clear the previous notifications. */
        xTaskNotifyWaitIndexed( uxIndexToTest, notifyUINT32_MAX, 0, &ulNotifiedValue, 0 );
    }

    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* No task notification within the array of task notifications should
         * have any notification pending, so an attempt to clear the notification
         * state should fail. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            configASSERT( xTaskNotifyStateClearIndexed( NULL, uxOtherIndexes ) == pdFALSE );
        }

        /* Get the task to notify itself using the task notification at index
         * uxIndexToTest within the array of task notifications.  This is not a
         * normal thing to do, and is only done here for test purposes. */
        xTaskNotifyAndQueryIndexed( xTaskToNotify, uxIndexToTest, ulFirstNotifiedConst, eSetValueWithoutOverwrite, &ulPreviousValue );

        /* Now the notification state should be eNotified, so it should now be
         * possible to clear the notification state.  Other indexes should still
         * not have a notification pending - likewise uxIndexToTest should not have
         * a notification pending once it has been cleared. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            if( uxOtherIndexes == uxIndexToTest )
            {
                configASSERT( xTaskNotifyStateClearIndexed( NULL, uxOtherIndexes ) == pdTRUE );
            }

            configASSERT( xTaskNotifyStateClearIndexed( NULL, uxOtherIndexes ) == pdFALSE );
        }
    }

    /* ------------------------------------------------------------------------
     * For each task notification within the array of task notifications, clear
     * bits in the notification value. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* Get the task to set all bits in its task notification at index
        * uxIndexToTest within its array of task notifications.  This is not a
        * normal thing to do, and is only done here for test purposes. */
        xTaskNotifyIndexed( xTaskToNotify, uxIndexToTest, notifyUINT32_MAX, eSetBits );

        /* Now clear the top bytes - the returned value from the first call
         * should indicate that previously all bits were set. */
        configASSERT( ulTaskNotifyValueClearIndexed( xTaskToNotify, uxIndexToTest, notifyUINT32_HIGH_BYTE ) == notifyUINT32_MAX );

        /* Next clear the bottom bytes - the returned value this time should
         * indicate that the top byte was clear (before the bottom byte was
         * cleared. */
        configASSERT( ulTaskNotifyValueClearIndexed( xTaskToNotify, uxIndexToTest, notifyUINT32_LOW_BYTE ) == ( notifyUINT32_MAX & ~notifyUINT32_HIGH_BYTE ) );

        /* Next clear all bytes - the returned value should indicate that previously the
         * high and low bytes were clear. */
        configASSERT( ulTaskNotifyValueClearIndexed( xTaskToNotify, uxIndexToTest, notifyUINT32_MAX ) == ( notifyUINT32_MAX & ~notifyUINT32_HIGH_BYTE & ~notifyUINT32_LOW_BYTE ) );

        /* Now all bits should be clear. */
        configASSERT( ulTaskNotifyValueClearIndexed( xTaskToNotify, uxIndexToTest, notifyUINT32_MAX ) == 0 );
        configASSERT( ulTaskNotifyValueClearIndexed( xTaskToNotify, uxIndexToTest, 0UL ) == 0 );
        configASSERT( ulTaskNotifyValueClearIndexed( xTaskToNotify, uxIndexToTest, notifyUINT32_MAX ) == 0 );

        /* Now the notification state should be eNotified, so it should now be
         * possible to clear the notification state. */
        configASSERT( xTaskNotifyStateClearIndexed( NULL, uxIndexToTest ) == pdTRUE );
        configASSERT( xTaskNotifyStateClearIndexed( NULL, uxIndexToTest ) == pdFALSE );
    }

    /* Incremented to show the task is still running. */
    ulFineCycleCount++;

    /* Leave all bits cleared. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        xTaskNotifyWaitIndexed( uxIndexToTest, notifyUINT32_MAX, 0, NULL, 0 );
    }
}
/*-----------------------------------------------------------*/

static void prvSuspendedTaskTimerTestCallback( TimerHandle_t xExpiredTimer )
{
    static uint32_t ulCallCount = 0;
    static UBaseType_t uxIndexToNotify = 0;

    /* Remove compiler warnings about unused parameters. */
    ( void ) xExpiredTimer;

    /* Callback for a timer that is used to send notifications to a task while
     * it is suspended.  The timer tests the behaviour when 1: a task waiting for a
     * notification is suspended and then resumed without ever receiving a
     * notification, and 2: when a task waiting for a notification receives a
     * notification while it is suspended.  Run one of two tests on every other
     * invocation of this callback.  The notification is sent to the task
     * notification at index uxIndexToNotify. */
    if( ( ulCallCount & 0x01 ) == 0 )
    {
        vTaskSuspend( xTaskToNotify );
        configASSERT( eTaskGetState( xTaskToNotify ) == eSuspended );
        vTaskResume( xTaskToNotify );
    }
    else
    {
        vTaskSuspend( xTaskToNotify );

        /* Sending a notification while the task is suspended should pass, but
         * not cause the task to resume. */
        xTaskNotifyIndexed( xTaskToNotify, uxIndexToNotify, 1, eSetValueWithOverwrite );

        /* Use the next task notification within the array of task notifications
         * the next time around. */
        uxIndexToNotify++;

        if( uxIndexToNotify >= configTASK_NOTIFICATION_ARRAY_ENTRIES )
        {
            uxIndexToNotify = 0;
        }

        /* Make sure giving the notification didn't resume the task. */
        configASSERT( eTaskGetState( xTaskToNotify ) == eSuspended );

        vTaskResume( xTaskToNotify );
    }

    ulCallCount++;
}
/*-----------------------------------------------------------*/

static void prvNotifyingTimerCallback( TimerHandle_t xNotUsed )
{
    static BaseType_t uxIndexToNotify = 0;

    ( void ) xNotUsed;

    /* "Give" the task notification (which increments the target task
     * notification value) at index uxIndexToNotify within the array of task
     * notifications. */
    xTaskNotifyGiveIndexed( xTaskToNotify, uxIndexToNotify );

    /* Use the next task notification within the array of task notifications the
     * next time around. */
    uxIndexToNotify++;

    if( uxIndexToNotify >= configTASK_NOTIFICATION_ARRAY_ENTRIES )
    {
        uxIndexToNotify = 0;
    }
}
/*-----------------------------------------------------------*/

static void prvTestNotifyTaskWhileSuspended( void )
{
    UBaseType_t uxIndexToTest, uxOtherIndexes;
    BaseType_t xReturned;
    uint32_t ulNotifiedValue;

    /* Raise the task's priority so it can suspend itself before the timer
     * expires. */
    vTaskPrioritySet( NULL, configMAX_PRIORITIES - 1 );

    /* Perform the test on each task notification within the array or task
     * notifications. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        /* Ensure no notifications within the array of task notifications are
         * pending. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            xReturned = xTaskNotifyWaitIndexed( uxOtherIndexes, 0, 0, NULL, 0 );
            configASSERT( xReturned == pdFALSE );
            ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        }

        /* Start the timer that will try notifying this task while it is
         * suspended, then wait for a notification.  The first time the callback
         * executes the timer will suspend the task, then resume the task, without
         * ever sending a notification to the task. */
        ulNotifiedValue = 0;
        xTimerStart( xNotifyWhileSuspendedTimer, portMAX_DELAY );

        /* Check a notification is not received on the task notification at
         * index uxIndexToTest within the array of task notifications. */
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, 0, 0, &ulNotifiedValue, portMAX_DELAY );
        configASSERT( xReturned == pdFALSE );
        configASSERT( ulNotifiedValue == 0 );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* Check none of the task notifications within the array of task
         * notifications as been notified. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            xReturned = xTaskNotifyWaitIndexed( uxOtherIndexes, 0, 0, &ulNotifiedValue, 0 );
            configASSERT( xReturned == pdFALSE );
            ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        }

        /* Start the timer that will try notifying this task while it is
         * suspended, then wait for a notification at index uxIndexToTest within
         * the array of task notifications.  The second time the callback executes
         * the timer will suspend the task, notify the task, then resume the task
         * (previously it was suspended and resumed without being notified). */
        xTimerStart( xNotifyWhileSuspendedTimer, portMAX_DELAY );

        /* Check a notification is only received in the index within the array
         * of task notifications under test. */
        xReturned = xTaskNotifyWaitIndexed( uxIndexToTest, 0, 0, &ulNotifiedValue, portMAX_DELAY );
        configASSERT( xReturned == pdPASS );
        ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
        configASSERT( ulNotifiedValue != 0 );

        /* Check a notification is not received in any index within the array
         * of task notifications at and below the index being tested have a notification
         * value, and that indexes above the index being tested to not have
         * notification values. */
        for( uxOtherIndexes = 0; uxOtherIndexes < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxOtherIndexes++ )
        {
            xReturned = xTaskNotifyWaitIndexed( uxOtherIndexes, 0, 0, &ulNotifiedValue, 0 );
            configASSERT( xReturned == pdFALSE );

            if( uxOtherIndexes <= uxIndexToTest )
            {
                configASSERT( ulNotifiedValue == 1 );
            }
            else
            {
                configASSERT( ulNotifiedValue == 0 );
            }

            ( void ) xReturned; /* Remove compiler warnings in case configASSERT() is not defined. */
            ( void ) ulNotifiedValue;
        }
    }

    /* Return the task to its proper priority */
    vTaskPrioritySet( NULL, notifyTASK_PRIORITY );

    /* Incremented to show the task is still running. */
    ulFineCycleCount++;

    /* Leave all bits cleared. */
    for( uxIndexToTest = 0; uxIndexToTest < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToTest++ )
    {
        xTaskNotifyWaitIndexed( uxIndexToTest, notifyUINT32_MAX, 0, NULL, 0 );
    }
}
/* ------------------------------------------------------------------------ */

static void prvBlockOnTheNotifiedIndexed( void )
{
    const TickType_t xTimerPeriod = pdMS_TO_TICKS( 100 ), xMargin = pdMS_TO_TICKS( 50 ), xDontBlock = 0;
    UBaseType_t uxIndex, uxIndexToNotify;
    uint32_t ulReceivedValue;
    BaseType_t xReturned;

    /* Set the value of each notification in the array of task notifications to
     * the value of its index position plus 1 so everything starts in a known
     * state, then clear the notification state ready for the next test.  Plus 1 is
     * used because the index under test will use 0. */
    for( uxIndex = 0; uxIndex < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndex++ )
    {
        xTaskNotifyIndexed( xTaskToNotify, uxIndex, uxIndex + 1, eSetValueWithOverwrite );
        xTaskNotifyStateClearIndexed( xTaskToNotify, uxIndex );
    }

    /* Peform the test on each task notification within the array of task
     * notifications. */
    for( uxIndexToNotify = 0; uxIndexToNotify < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToNotify++ )
    {
        /* Set the notification value of the index being tested to 0 so the
         * notification value increment/decrement functions can be tested. */
        xTaskNotifyIndexed( xTaskToNotify, uxIndexToNotify, 0, eSetValueWithOverwrite );
        xTaskNotifyStateClearIndexed( xTaskToNotify, uxIndexToNotify );

        /* Start the software timer then wait for it to notify this task.  Block
         * on the notification index we expect to receive the notification on.  The
         * margin is to ensure the task blocks longer than the timer period. */
        xTimerStart( xIncrementingIndexTimer, portMAX_DELAY );
        ulReceivedValue = ulTaskNotifyTakeIndexed( uxIndexToNotify, pdFALSE, xTimerPeriod + xMargin );

        /* The notification value was initially zero, and should have been
         * incremented by the software timer, so now one.  It will also have been
         * decremented again by the call to ulTaskNotifyTakeIndexed() so gone back
         * to 0. */
        configASSERT( ulReceivedValue == 1UL );
        ( void ) ulReceivedValue; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* No other notification indexes should have changed, and therefore should
         * still have their value set to their index plus 1 within the array of
         * notifications. */
        for( uxIndex = 0; uxIndex < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndex++ )
        {
            if( uxIndex != uxIndexToNotify )
            {
                xReturned = xTaskNotifyWaitIndexed( uxIndex, 0, 0, &ulReceivedValue, xDontBlock );
                configASSERT( xReturned == pdFALSE );
                configASSERT( ulReceivedValue == ( uxIndex + 1 ) );
                ( void ) ulReceivedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
                ( void ) xReturned;
            }
        }

        /* Reset the notification value for the index just tested back to the
         * index value plus 1 ready for the next iteration around this loop. */
        xTaskNotifyIndexed( xTaskToNotify, uxIndexToNotify, uxIndexToNotify + 1, eSetValueWithOverwrite );
        xTaskNotifyStateClearIndexed( xTaskToNotify, uxIndexToNotify );

        /* Incremented to show the task is still running. */
        ulFineCycleCount++;
    }
}
/* ------------------------------------------------------------------------ */

static void prvBlockOnANonNotifiedIndexed( void )
{
    const TickType_t xTimerPeriod = pdMS_TO_TICKS( 100 ), xMargin = pdMS_TO_TICKS( 50 ), xDontBlock = 0;
    UBaseType_t uxIndex, uxIndexToNotify;
    uint32_t ulReceivedValue;
    BaseType_t xReturned;
    TickType_t xTimeBeforeBlocking, xTimeNow, xTimeDifference;

    /* Set all notify values within the array of tasks notifications to zero
     * ready for the next test. */
    for( uxIndexToNotify = 0; uxIndexToNotify < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToNotify++ )
    {
        ulTaskNotifyValueClearIndexed( xTaskToNotify, uxIndexToNotify, notifyUINT32_MAX );
    }

    /* Perform the test for each notification within the array of task
     * notifications. */
    for( uxIndexToNotify = 0; uxIndexToNotify < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToNotify++ )
    {
        /* Start the software timer then wait for it to notify this task.  Block
         * on a notification index that we do not expect to receive the notification
         * on.  The margin is to ensure the task blocks longer than the timer period. */
        xTimerStart( xIncrementingIndexTimer, portMAX_DELAY );
        xTimeBeforeBlocking = xTaskGetTickCount();

        if( uxIndexToNotify == ( configTASK_NOTIFICATION_ARRAY_ENTRIES - 1 ) )
        {
            /* configTASK_NOTIFICATION_ARRAY_ENTRIES - 1 is to be notified, so
             * block on index 0. */
            uxIndex = 0;
        }
        else
        {
            /* The next index to get notified will be uxIndexToNotify, so block
             * on uxIndexToNotify + 1 */
            uxIndex = uxIndexToNotify + 1;
        }

        xReturned = xTaskNotifyWaitIndexed( uxIndex, 0, 0, &ulReceivedValue, xTimerPeriod + xMargin );

        /* The notification will have been sent to task notification at index
         * uxIndexToNotify in this task by the timer callback after xTimerPeriodTicks.
         * The notification should not have woken this task, so xReturned should
         * be false and at least xTimerPeriod + xMargin ticks should have passed. */
        configASSERT( xReturned == pdFALSE );
        xTimeNow = xTaskGetTickCount();
        xTimeDifference = xTimeNow - xTimeBeforeBlocking;
        configASSERT( xTimeDifference >= ( xTimerPeriod + xMargin ) );
        ( void ) xReturned; /* Remove compiler warnings if configASSERT() is not defined. */
        ( void ) xTimeBeforeBlocking;
        ( void ) xTimeDifference;

        /* Only the notification at index position uxIndexToNotify should be
         * set.  Calling this function will clear it again. */
        for( uxIndex = 0; uxIndex < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndex++ )
        {
            xReturned = xTaskNotifyWaitIndexed( uxIndex, 0, 0, &ulReceivedValue, xDontBlock );

            if( uxIndex == uxIndexToNotify )
            {
                /* Expect the notification state to be set and the notification
                 * value to have been incremented. */
                configASSERT( xReturned == pdTRUE );
                configASSERT( ulReceivedValue == 1 );

                /* Set the notification value for this array index back to 0. */
                ulTaskNotifyValueClearIndexed( xTaskToNotify, uxIndex, notifyUINT32_MAX );
            }
            else
            {
                /* Expect the notification state to be clear and the notification
                 * value to remain at zer0. */
                configASSERT( xReturned == pdFALSE );
                configASSERT( ulReceivedValue == 0 );
            }
        }

        /* Incremented to show the task is still running. */
        ulFineCycleCount++;
    }
}
/* ------------------------------------------------------------------------ */

static void prvBlockOnNotificationsComingFromInterrupts( void )
{
    UBaseType_t uxIndex, uxIndexToNotify;
    uint32_t ulReceivedValue;
    BaseType_t xReturned;
    const TickType_t xDontBlock = 0;

    /* Set the value of each notification within the array of task notifications
     * to zero so the task can block on xTaskNotifyTake(). */
    for( uxIndex = 0; uxIndex < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndex++ )
    {
        xTaskNotifyIndexed( xTaskToNotify, uxIndex, 0, eSetValueWithOverwrite );
        xTaskNotifyStateClearIndexed( xTaskToNotify, uxIndex );
    }

    /* Perform the test on each task notification within the array of task
     * notifications. */
    for( uxIndexToNotify = 0; uxIndexToNotify < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndexToNotify++ )
    {
        /* Tell the interrupt to send the next notification. */
        taskENTER_CRITICAL();
        {
            /* Don't expect to find xSendNotificationFromISR set at this time as
             * the interrupt should have cleared it back to pdFALSE last time it
             * executed. */
            configASSERT( xSendNotificationFromISR == pdFALSE );
            xSendNotificationFromISR = pdTRUE;
        }
        taskEXIT_CRITICAL();

        /* Wait for a notification on the task notification at index
        * uxIndexToNotify within the array of task notifications. */
        ulReceivedValue = ulTaskNotifyTakeIndexed( uxIndexToNotify, pdTRUE, portMAX_DELAY );

        /* Interrupt should have reset xSendNotificationFromISR after it sent
         * the notification. */
        configASSERT( xSendNotificationFromISR == pdFALSE );

        /* The notification value was initially zero, and should have been
         * incremented by the interrupt, so now one. */
        configASSERT( ulReceivedValue == 1UL );
        ( void ) ulReceivedValue; /* Remove compiler warnings in case configASSERT() is not defined. */

        /* No other notification indexes should have changed, and therefore should
         * still have their value set to 0.  The value in array index uxIndexToNotify
         * should also have been decremented back to zero by the call to
         * ulTaskNotifyTakeIndexed(). */
        for( uxIndex = 0; uxIndex < configTASK_NOTIFICATION_ARRAY_ENTRIES; uxIndex++ )
        {
            xReturned = xTaskNotifyWaitIndexed( uxIndexToNotify, 0, 0, &ulReceivedValue, xDontBlock );
            configASSERT( xReturned == pdFALSE );
            configASSERT( ulReceivedValue == 0 );
            ( void ) ulReceivedValue; /* Remove compiler warnings in case configASSERT() is not defined. */
            ( void ) xReturned;
        }

        /* Incremented to show the task is still running. */
        ulFineCycleCount++;
    }
}
/*-----------------------------------------------------------*/

void xNotifyArrayTaskFromISR( void )
{
    static BaseType_t xAPIToUse = 0;
    uint32_t ulPreviousValue;
    const uint32_t ulUnexpectedValue = 0xff;
    static UBaseType_t uxIndexToNotify = 0;

    /* Check the task notification demo task was actually created. */
    configASSERT( xTaskToNotify );

    /* The task sets xSendNotificationFromISR to pdTRUE each time it wants this
     * interrupt (this function runs in the RTOS tick hook) to send the next
     * notification. */
    if( xSendNotificationFromISR == pdTRUE )
    {
        xSendNotificationFromISR = pdFALSE;

        /* Test using both vTaskNotifyGiveFromISR(), xTaskNotifyFromISR()
         * and xTaskNotifyAndQueryFromISR(). The notification is set to the task
         * notification at index uxIndexToNotify within the array of task
         * notifications. */
        switch( xAPIToUse )
        {
            case 0:
                vTaskNotifyGiveIndexedFromISR( xTaskToNotify, uxIndexToNotify, NULL );
                xAPIToUse++;
                break;

            case 1:
                xTaskNotifyIndexedFromISR( xTaskToNotify, uxIndexToNotify, 0, eIncrement, NULL );
                xAPIToUse++;
                break;

            case 2:
                ulPreviousValue = ulUnexpectedValue;
                xTaskNotifyAndQueryIndexedFromISR( xTaskToNotify, uxIndexToNotify, 0, eIncrement, &ulPreviousValue, NULL );
                configASSERT( ulPreviousValue == 0 );
                xAPIToUse = 0;
                break;

            default: /* Should never get here!. */
                break;
        }

        /* Use the next index in the array of task notifications the next time
         * around. */
        uxIndexToNotify++;

        if( uxIndexToNotify >= configTASK_NOTIFICATION_ARRAY_ENTRIES )
        {
            uxIndexToNotify = 0;
        }
    }
}
/*-----------------------------------------------------------*/

/* This is called to check the created tasks are still running and have not
 * detected any errors. */
BaseType_t xAreTaskNotificationArrayTasksStillRunning( void )
{
    static uint32_t ulLastFineCycleCount = 0, ulLastCourseCycleCount = 0, ulCallCount = 0;
    const uint32_t ulCallsBetweenCourseCycleCountChecks = 3UL;
    static BaseType_t xErrorStatus = pdPASS;

    /* Check the cycle count is still incrementing to ensure the task is still
     * actually running.  The fine counter is incremented within individual test
     * functions.  The course counter is incremented one each time all the test
     * functions have been executed to ensure all the tests are running. */
    if( ulLastFineCycleCount == ulFineCycleCount )
    {
        xErrorStatus = pdFAIL;
    }
    else
    {
        ulLastFineCycleCount = ulFineCycleCount;
    }

    ulCallCount++;

    if( ulCallCount >= ulCallsBetweenCourseCycleCountChecks )
    {
        ulCallCount = 0;

        if( ulLastCourseCycleCount == ulCourseCycleCounter )
        {
            xErrorStatus = pdFAIL;
        }
        else
        {
            ulLastCourseCycleCount = ulCourseCycleCounter;
        }
    }

    return xErrorStatus;
}
/*-----------------------------------------------------------*/

static UBaseType_t prvRand( void )
{
    const size_t uxMultiplier = ( size_t ) 0x015a4e35, uxIncrement = ( size_t ) 1;

    /* Utility function to generate a pseudo random number. */
    uxNextRand = ( uxMultiplier * uxNextRand ) + uxIncrement;
    return( ( uxNextRand >> 16 ) & ( ( size_t ) 0x7fff ) );
}
/*-----------------------------------------------------------*/