"When used for input capture, the value of the PER register determines how input capture values are interpreted. If bit 15 of PER is set to one, the entire 16 bit counter value is stored in the capture buffer. If bit 15 of PER is zero, the event polarity is stored in bit 15 in the capture buffer. This can be used to measure frequency parameters like duty cycle using only one input pin and one capture channel."
Чтобля за the event polarity is stored in bit 15? Как вона мне "can be used to measure frequency parameters"?