When a capture is made by a capture unit and there is already at least one valid value in the FIFO (indicated by CAPxFIFO bits not equal to zero), the corresponding interrupt flag is set, and if unmasked, a peripheral interrupt request is generated. Thus, a pair of captured counter values can be read by an interrupt service routine if the interrupt is used. If an interrupt is not desired, either
the interrupt flag or the status bits can be polled to determine if two captures have occurred allowing the captured counter values to be read