queue.

h

 portBASE_TYPE xQueueReceiveFromISR(
                                       xQueueHandle xQueue,
                                       void *pvBuffer,
                                       portBASE_TYPE *pxTaskWoken
                                   );

Receive an item from a queue. It is safe to use this function from within an interrupt service routine.

Parameters

xQueue	The handle to the queue from which the item is to be received.
pvBuffer	Pointer to the buffer into which the received item will be copied.
pxTaskWoken	A task may be blocked waiting for space to become available on the queue. If xQueueReceiveFromISR causes such a task to unblock pxTaskWoken will get set to pdTRUE, otherwise pxTaskWoken will remain unchanged.

Returns: pdTRUE if an item was successfully received from the queue, otherwise pdFALSE.

Example usage:

 xQueueHandle xQueue;

Function to create a queue and post some values.
 void vAFunction( void *pvParameters )
 {
 char cValueToPost;
 const portTickType xBlockTime = ( portTickType )0xff;

Create a queue capable of containing 10 characters.
    xQueue = xQueueCreate( 10, sizeof( char ) );
    if( xQueue == 0 )
    {
Failed to create the queue.
    }

...

Post some characters that will be used within an ISR.  If the queue
is full then this task will block for xBlockTime ticks.
    cValueToPost = 'a';
    xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime );
    cValueToPost = 'b';
    xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime );

... keep posting characters ... this task may block when the queue
becomes full.

cValueToPost = 'c';
xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime );

 }

ISR that outputs all the characters received on the queue.
 void vISR_Routine( void )
 {
 portBASE_TYPE xTaskWokenByReceive = pdFALSE;
 char cRxedChar;

    while( xQueueReceiveFromISR( xQueue, ( void * ) &cRxedChar, &xTaskWokenByReceive) )
    {
A character was received.  Output the character now.
        vOutputCharacter( cRxedChar );

If removing the character from the queue woke the task that was
posting onto the queue cTaskWokenByReceive will have been set to
pdTRUE.  No matter how many times this loop iterates only one
task will be woken.
    }

    if( cTaskWokenByPost != ( char ) pdFALSE;
    {
        taskYIELD ();
    }
 }

h

 BaseType_t xQueueReceiveFromISR(
                                       QueueHandle_t    xQueue,
                                       void *pvBuffer,
                                       BaseType_t *pxTaskWoken
                                   );

Receive an item from a queue. It is safe to use this function from within an interrupt service routine.

Parameters

xQueue	The handle to the queue from which the item is to be received.
pvBuffer	Pointer to the buffer into which the received item will be copied.
pxTaskWoken	A task may be blocked waiting for space to become available on the queue. If xQueueReceiveFromISR causes such a task to unblock pxTaskWoken will get set to pdTRUE, otherwise pxTaskWoken will remain unchanged.

Returns: pdTRUE if an item was successfully received from the queue, otherwise pdFALSE.

Example usage:

 QueueHandle_t xQueue;

Function to create a queue and post some values.
 void vAFunction( void *pvParameters )
 {
 char cValueToPost;
 const TickType_t xTicksToWait = ( TickType_t )0xff;

Create a queue capable of containing 10 characters.
    xQueue = xQueueCreate( 10, sizeof( char ) );
    if( xQueue == 0 )
    {
Failed to create the queue.
    }

...

Post some characters that will be used within an ISR.  If the queue
is full then this task will block for xTicksToWait ticks.
    cValueToPost = 'a';
    xQueueSend( xQueue, ( void * ) &cValueToPost, xTicksToWait );
    cValueToPost = 'b';
    xQueueSend( xQueue, ( void * ) &cValueToPost, xTicksToWait );

... keep posting characters ... this task may block when the queue
becomes full.

cValueToPost = 'c';
xQueueSend( xQueue, ( void * ) &cValueToPost, xTicksToWait );

 }

ISR that outputs all the characters received on the queue.
 void vISR_Routine( void )
 {
 BaseType_t xTaskWokenByReceive = pdFALSE;
 char cRxedChar;

    while( xQueueReceiveFromISR( xQueue, ( void * ) &cRxedChar, &xTaskWokenByReceive) )
    {
A character was received.  Output the character now.
        vOutputCharacter( cRxedChar );

If removing the character from the queue woke the task that was
posting onto the queue cTaskWokenByReceive will have been set to
pdTRUE.  No matter how many times this loop iterates only one
task will be woken.
    }

    if( cTaskWokenByPost != ( char ) pdFALSE;
    {
        taskYIELD ();
    }
 }

h

 portBASE_TYPE xQueueReceiveFromISR(
                                       xQueueHandle pxQueue,
                                       void *pvBuffer,
                                       portBASE_TYPE    *pxTaskWoken
                                   );

Receive an item from a queue. It is safe to use this function from within an interrupt service routine.

Parameters

pxQueue	The handle to the queue from which the item is to be received.
pvBuffer	Pointer to the buffer into which the received item will be copied.
pxTaskWoken	A task may be blocked waiting for space to become available on the queue. If xQueueReceiveFromISR causes such a task to unblock pxTaskWoken will get set to pdTRUE, otherwise pxTaskWoken will remain unchanged.

Returns: pdTRUE if an item was successfully received from the queue, otherwise pdFALSE.

Example usage:

 xQueueHandle xQueue;

Function to create a queue and post some values.
 void vAFunction( void *pvParameters )
 {
 char cValueToPost;
 const portTickType xBlockTime = ( portTickType )0xff;

Create a queue capable of containing 10 characters.
    xQueue = xQueueCreate( 10, sizeof( char ) );
    if( xQueue == 0 )
    {
Failed to create the queue.
    }

...

Post some characters that will be used within an ISR.  If the queue
is full then this task will block for xBlockTime ticks.
    cValueToPost = 'a';
    xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime );
    cValueToPost = 'b';
    xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime );

... keep posting characters ... this task may block when the queue
becomes full.

cValueToPost = 'c';
xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime );

 }

ISR that outputs all the characters received on the queue.
 void vISR_Routine( void )
 {
 portBASE_TYPE xTaskWokenByReceive = pdFALSE;
 char cRxedChar;

    while( xQueueReceiveFromISR( xQueue, ( void * ) &cRxedChar, &xTaskWokenByReceive) )
    {
A character was received.  Output the character now.
        vOutputCharacter( cRxedChar );

If removing the character from the queue woke the task that was
posting onto the queue cTaskWokenByReceive will have been set to
pdTRUE.  No matter how many times this loop iterates only one
task will be woken.
    }

    if( cTaskWokenByPost != ( char ) pdFALSE;
    {
        taskYIELD ();
    }
 }

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