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is used to indicate whether the delay is absolute or relative:
OS_OPT_TIME_DLY
Specifies a relative delay.
OS_OPT_TIME_PERIODIC
Specifies periodic mode.
OS_OPT_TIME_MATCH
Specifies that the task will wake up when OSTickCtr reaches the value specified by dly
p_err
is a pointer to a variable that will contain an error code returned by this function.
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