Originally Posted by
dmanthree
I understand that, but it knows when I'm pedaling and can count cadence pretty closely. On Zwift, when I stop pedaling my avatar does. How is Zwift counting cadence through the Snap?
I don't know for certain but I can take an educated guess. The Snap measures power likely by sensing the resistance (physical, not electrical) against the roller. This resistance is not constant: it will be highest when you are on a downstroke and lowest when you are at the bottom of a stroke. So, measure the instantaneous resistance and count peaks per unit of time, then divide by 2. Voilą, you have cadence.