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A periodic delay means the period (in number of ticks). µC/OS-III saves the current time + dly in .TcikCtrPrevTickCtrPrev so the next time OSTimeDly() is called, we use .TickDlyPrev + dly.
An absolute delay means that the task will wake up when OSTickCtr reaches the value specified by dly.
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Specifies a relative delay.
OS_OPT_TIME_TIMEOUT
Same as OS_OPT_TIME_DLY.
OS_OPT_TIME_PERIODIC
Specifies periodic mode.
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If OS_CFG_ARG_CHK_EN is set to 1 in DEF_ENABLED in os_cfg.h: if a valid option is not specified.
OS_ERR_OS_NOT_RUNNING
If OS_CFG_INVALID_OS_CALLS_CHK_EN is set to DEF_ENABLED in os_cfg.h: if µC/OS-III is not running yet.
OS_ERR_SCHED_LOCKED
If the scheduler is locked.
OS_ERR_TIME_DLY_ISR
If OS_CFG_CALLED_FROM_ISR_CHK_EN set to 1 in DEF_ENABLED in os_cfg.h: if calling this function from an ISR.
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