56.6.2.3.1 Delay Measurement
To measure the delay between the channel x comparator output (OCx) and the feedback from the bridge driver of the MOSFETs (see the figure below), the bit TCTS in the PWM Channel Mode Register must be at 0. This defines the comparator output of the channel x as the TC trigger source. The TIOB trigger (TC internal input) is used to start the TC; the TIOA input (from PAD) is used to capture the delay.