SPRUIV7B May 2022 – September 2023 AM620-Q1 , AM623 , AM625 , AM625-Q1 , AM625SIP
There are four hardware time stamp inputs ( CPTS_HW[1:4]_TS_PUSH events) that can cause hardware time stamp push events to be loaded into the Event FIFO. Each time stamp input is mapped in the device as shown in CPTS Integration. The event is loaded into the event FIFO on the rising edge of the timer, and the PORT_NUMBER field in the CPSW_CPTS_EVENT_1_REG register indicates the hardware push input that caused the event (encoded).
The hardware time stamp inputs are asynchronous and are low frequency signals. The CPTS logic synchronizes and performs a rising edge detect on the incoming asynchronous input.
Each hardware time stamp input must be asserted for at least 10 periods of the selected CPTS_RFT_CLK clock. Each input can be enabled or disabled by setting the respective bits in the CPSW_CPTS_CONTROL_REG register.
Hardware time stamps are intended to be an extremely low frequency signals, such that the event FIFO does not overrun. Software must keep up with the event FIFO and ensure that there is no overrun, or events will be lost.