This table shows the difference in API for message-queue management.
Panel |
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µC/OS-II (os_q.c ) | µC/OS-III (os_q.c ) | Note |
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void *
OSQAccept(
OS_EVENT *pevent,
INT8U *perr); |
| (1) | OS_EVENT *
OSQCreate(
void **start,
INT16U size); | void
OSQCreate(
OS_Q *p_q,
CPU_CHAR *p_name,
OS_MSG_QTY max_qty,
OS_ERR *p_err); | (2) | OS_EVENT *
OSQDel(
OS_EVENT *pevent,
INT8U opt,
INT8U *perr); | OS_OBJ_QTY,
OSQDel(
OS_Q *p_q,
OS_OPT opt,
OS_ERR *p_err); |
| INT8U
OSQFlush(
OS_EVENT *pevent); | OS_MSG_QTY
OSQFlush(
OS_Q *p_q,
OS_ERR *p_err); |
| void *
OSQPend(
OS_EVENT *pevent,
INT32U timeout,
INT8U *perr); | void *
OSQPend(
OS_Q *p_q,
OS_MSG_SIZE *p_msg_size,
OS_TICK timeout,
OS_OPT opt,
CPU_TS *p_ts,
OS_ERR *p_err); | (3) | INT8U
OSQPendAbort(
OS_EVENT *pevent,
INT8U opt,
INT8U *perr); | OS_OBJ_QTY
OSQPendAbort(
OS_Q *p_q,
OS_OPT opt,
OS_ERR *p_err); |
| INT8U
OSQPost(
OS_EVENT *pevent,
void *pmsg); | void
OSQPost(
OS_Q *p_q,
void *p_void,
OS_MSG_SIZE msg_size,
OS_OPT opt,
OS_ERR *p_err); | (4) | INT8U
OSQPostFront(
OS_EVENT *pevent,
void *pmsg); |
|
| INT8U
OSQPostOpt(
OS_EVENT *pevent,
void *pmsg,
INT8U opt); |
| (4) | INT8U
OSQQuery(
OS_EVENT *pevent,
OS_Q_DATA *p_q_data); |
| (5) |
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Panel |
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(1) In µC/OS-III, there is no “accept” API as this feature is built into the OSQPend() by specifying the OS_OPT_PEND_NON_BLOCKING option. (2) In µC/OS-II, OSQCreate() returns the address of an OS_EVENT , which is used as the “handle” to the message queue. In µC/OS-III, the application must allocate storage for an OS_Q object, which serves the same purpose as the OS_EVENT . The benefit in µC/OS-III is that it is not necessary to predetermine at compile time, the number of message queues. (3) µC/OS-III returns additional information when a message queue is posted. Specifically, the sender includes the size of the message and takes a snapshot of the current timestamp and stores it in the message. The receiver of the message therefore knows when the message was posted. (4) In µC/OS-III, OSQPost() offers a number of options that replaces the three post functions provided in µC/OS-II. (5) µC/OS-III does not provide query services as they were rarely used. |