PXI-6624 Counter/Timer Module Connection

Hello Everyone,

I have a PXI-6624 Counter/Timer Module. This is User Manuel link.

According to user manuel, input-output connections and pin assignments are shown below. I want to read PWM frequency and duty cycle by using input connections and generate PWM signal by using output connection. In pin assignments, there is there different things (source, gate and aux). What is the difference between these connection types? Could you explain with an example for each?

Thank you!