What's the difference between os_itv_wait and os_dly_wait?

Note that os_dly_wait() starts the timer from when it's called. This can result in a time drift for a periodic function.

Note also that a task may not use both os_itv_wait() and os_dly_wait(). They are mutually exclusive.

Note that os_dly_wait() starts the timer from when it's called. This can result in a time drift for a periodic function.

Note also that a task may not use both os_itv_wait() and os_dly_wait(). They are mutually exclusive.

Thanks Mr Westermark for your answer. Can you tell me when the os_itv_wait() starts the timer?

Since it is a periodic timer, it counts from os_itv_set() and will restart continuously without any gap while your task runs.

Have you looked at the documentation in the keil directory on your hdd or the online manual on this site?