21.1.6.6 Gated Window Measurement Mode

This mode measures the duty cycle of the signal input over a known input window. It does so by incrementing the timer on each pulse of the clock signal while the signal input is high, updating the SMTxCPR register and resetting the timer on every rising edge of the window input after the first. See the figures below.

Figure 21-11. Gated Windowed Measurement Mode, Repeat Acquisition Timing Diagram
Figure 21-12. Gated Windowed Measurement Mode, Single Acquisition Timing Diagram