SWCU193 April 2023 CC2340R2 , CC2340R5 , CC2340R5-Q1
The SYSTIM is a 34-bit, 5-channel wrap-around timer with a per-channel selectable 32b slice with either a 1 us resolution and 1h11m35s range or 250 ns resolution and 17m54s range. All channels support both capture and single-shot compare (posting an event) operation. One channel is reserved for system software, three channels are reserved for radio software and one channel is freely available to user applications.
For software convenience there is a hardware synchronization mechanism which automatically ensures that the RTC and SYSTIM share a common time base (albeit with different resolutions/spans). Another software convenience feature is that SYSTIM qualifies any submitted compare values so that the timer channel immediately triggers if the submitted event is in the immediate past (4.294s with 1 us resolution and 1.049s with 250 ns resolution).