SPRUIW9C October 2021 – March 2024 TMS320F280033 , TMS320F280034 , TMS320F280034-Q1 , TMS320F280036-Q1 , TMS320F280036C-Q1 , TMS320F280037 , TMS320F280037-Q1 , TMS320F280037C , TMS320F280037C-Q1 , TMS320F280038-Q1 , TMS320F280038C-Q1 , TMS320F280039 , TMS320F280039-Q1 , TMS320F280039C , TMS320F280039C-Q1
Figure 21-12 shows an example of continuous capture operation (Mod4 counter wraps around). In this figure, TSCTR counts-up without resetting and capture events are qualified on the rising edge only, this gives period (and frequency) information.
On an event, the TSCTR contents (time-stamp) is first captured, then Mod4 counter is incremented to the next state. When the TSCTR reaches FFFFFFFF (maximum value), the Mod4 counter wraps around to 00000000 (not shown in Figure 21-12), if this occurs, the CTROVF (counter overflow) flag is set, and an interrupt (if enabled) occurs. Captured Time-stamps are valid at the point indicated by the diagram (after the fourth event); hence, event CEVT4 can conveniently be used to trigger an interrupt and the CPU can read data from the CAPx registers.