21-FreeRTOS队列集API函数

1queue.h
2QueueSetHandle_t xQueueCreateSet
3(
4const UBaseType_t uxEventQueueLength
5);

1/* 定义添加到队列集中的队列的长度。 */
 2#define QUEUE_LENGTH_1    10
 3#define QUEUE_LENGTH_2    10
 4
 5/* Binary semaphores have an effective length of 1. */
 6#define BINARY_SEMAPHORE_LENGTH    1
 7
 8/* Define the size of the item to be held by queue 1 and queue 2 respectively.
 9The values used here are just for demonstration purposes. */
10#define ITEM_SIZE_QUEUE_1    sizeof( uint32_t )
11#define ITEM_SIZE_QUEUE_2    sizeof( something_else_t )
12
13/* The combined length of the two queues and binary semaphore that will be
14added to the queue set. */
15#define COMBINED_LENGTH ( QUEUE_LENGTH_1 +
16QUEUE_LENGTH_2 +
17BINARY_SEMAPHORE_LENGTH )
18
19void vAFunction( void )
20{
21static QueueSetHandle_t xQueueSet;
22QueueHandle_t xQueue1, xQueue2, xSemaphore;
23QueueSetMemberHandle_t xActivatedMember;
24uint32_t xReceivedFromQueue1;
25something_else_t xReceivedFromQueue2;
26
27/* Create the queue set large enough to hold an event for every space in
28every queue and semaphore that is to be added to the set. */
29xQueueSet = xQueueCreateSet( COMBINED_LENGTH );
30
31/* Create the queues and semaphores that will be contained in the set. */
32xQueue1 = xQueueCreate( QUEUE_LENGTH_1, ITEM_SIZE_QUEUE_1 );
33xQueue2 = xQueueCreate( QUEUE_LENGTH_2, ITEM_SIZE_QUEUE_2 );
34
35/* Create the semaphore that is being added to the set. */
36xSemaphore = xSemaphoreCreateBinary();
37
38/* Check everything was created. */
39configASSERT( xQueueSet );
40configASSERT( xQueue1 );
41configASSERT( xQueue2 );
42configASSERT( xSemaphore );
43
44/* Add the queues and semaphores to the set. Reading from these queues and
45semaphore can only be performed after a call to xQueueSelectFromSet() has
46returned the queue or semaphore handle from this point on. */
47xQueueAddToSet( xQueue1, xQueueSet );
48xQueueAddToSet( xQueue2, xQueueSet );
49xQueueAddToSet( xSemaphore, xQueueSet );
50
51for( ;; )
52{
53/* Block to wait for something to be available from the queues or
54semaphore that have been added to the set. Don't block longer than
55200ms. */
56xActivatedMember = xQueueSelectFromSet( xQueueSet,
57200 / portTICK_PERIOD_MS );
58
59/* Which set member was selected? Receives/takes can use a block time
60of zero as they are guaranteed to pass because xQueueSelectFromSet()
61would not have returned the handle unless something was available. */
62if( xActivatedMember == xQueue1 )
63{
64xQueueReceive( xActivatedMember, &xReceivedFromQueue1, 0 );
65vProcessValueFromQueue1( xReceivedFromQueue1 );
66}
67else if( xActivatedMember == xQueue2 )
68{
69xQueueReceive( xActivatedMember, &xReceivedFromQueue2, 0 );
70vProcessValueFromQueue2( &xReceivedFromQueue2 );
71}
72else if( xActivatedMember == xSemaphore )
73{
74/* Take the semaphore to make sure it can be "given" again. */
75xSemaphoreTake( xActivatedMember, 0 );
76vProcessEventNotifiedBySemaphore();
77break;
78}
79else
80{
81/* The 200ms block time expired without an RTOS queue or semaphore
82being ready to process. */
83}
84}
85}

1queue.h
2BaseType_t xQueueAddToSet
3(
4QueueSetMemberHandle_t xQueueOrSemaphore,
5QueueSetHandle_t xQueueSet
6);

1queue.h
2BaseType_t xQueueRemoveFromSet
3(
4QueueSetMemberHandle_t xQueueOrSemaphore,
5QueueSetHandle_t xQueueSet
6);

1此示例假定 xQueueSet 是已创建的队列集， 而 xQueue 是已创建并添加到 xQueueSet 中的队列。
 2if( xQueueRemoveFromSet( xQueue, xQueueSet ) != pdPASS )
 3{
 4/* Either xQueue was not a member of the xQueueSet set, or xQueue is
 5not empty and therefore cannot be removed from the set. /
 6}
 7else
 8{
 9/ The queue was successfully removed from the set. */
10}

1queue.h
2QueueSetMemberHandle_t xQueueSelectFromSet
3(
4QueueSetHandle_t xQueueSet,
5const TickType_t xTicksToWait
6);

1queue.h
2QueueSetMemberHandle_t xQueueSelectFromSetFromISR
3(
4QueueSetHandle_t xQueueSet
5);