Event Flags API Changes

Owned by Former user (Deleted)
Last updated: Mar 23, 2021 by WES Admin
3 min read

The table below shows the API for event-flag management.

Event Flags API
µC/OS-II (os_flag.c)µC/OS-III (os_flag.c)Note
OS_FLAGS
OSFlagAccept(
    OS_FLAG_GRP *pgrp,
    OS_FLAGS flags,
    INT8U wait_type,
    INT8U *perr);

(1)
OS_FLAG_GRP *
OSFlagCreate(
    OS_FLAGS      flags,
    INT8U        *perr);
void
OSFlagCreate(
    OS_FLAG_GRP   *p_grp,
    CPU_CHAR      *p_name,
    OS_FLAGS       flags,
    OS_ERR        *p_err);
(2)
OS_FLAG_GRP *
OSFlagDel(
    OS_FLAG_GRP  *pgrp,
    INT8U         opt,
    INT8U        *perr);
OS_OBJ_QTY
OSFlagDel(
    OS_FLAG_GRP   *p_grp,
    OS_OPT         opt,
    OS_ERR        *p_err);

INT8U
OSFlagNameGet(
    OS_FLAG_GRP  *pgrp,
    INT8U       **pname,
    INT8U        *perr);


void
OSFlagNameSet(
    OS_FLAG_GRP  *pgrp,
    INT8U        *pname,
    INT8U        *perr);

(3)
OS_FLAGS
OSFlagPend(
    OS_FLAG_GRP  *pgrp,
    OS_FLAGS      flags,
    INT8U         wait_type,
    INT32U        timeout,
    INT8U        *perr);
OS_FLAGS
OSFlagPend(
    OS_FLAG_GRP   *p_grp,
    OS_FLAGS       flags,
    OS_TICK        timeout,
    OS_OPT         opt,
    OS_TS         *p_ts,
    OS_ERR        *p_err);

OS_FLAGS
OSFlagPendGetFlagsRdy(
    void);
OS_FLAGS
OSFlagPendGetFlagsRdy(
    OS_ERR        *p_err);

OS_FLAGS
OSFlagPost(
    OS_FLAG_GRP  *pgrp,
    OS_FLAGS      flags,
    INT8U         opt,
    INT8U        *perr);
OS_FLAGS
OSFlagPost(
    OS_FLAG_GRP   *p_grp,
    OS_FLAGS       flags,
    OS_OPT         opt,
    OS_ERR        *p_err);

OS_FLAGS
OSFlagQuery(
    OS_FLAG_GRP  *pgrp,
    INT8U        *perr);

(4)

(1) In µC/OS-III, there is no “accept” API. This feature is actually built-in the OSFlagPend() by specifying the OS_OPT_PEND_NON_BLOCKING option.

(2) In µC/OS-II, OSFlagCreate() returns the address of an OS_FLAG_GRP, which is used as the “handle” to the event-flag group. In µC/OS-III, the application must allocate storage for an OS_FLAG_GRP, which serves the same purpose as the OS_EVENT. The benefit in µC/OS-III is that it is not necessary to predetermine the number of event flags at compile time.

(3) In µC/OS-II, the user may assign a name to an event-flag group after the group is created. This functionality is built-into OSFlagCreate() for µC/OS-III.

(4) µC/OS-III does not provide query services, as they were rarely used in µC/OS-II.