Unfortunately, there's no way to independently switch two separate functions in an analog pedal. You can only switch the whole pedal on or off from the PBC. To have individual access to the pedal's two functions, you would have to manually stomp the pedal's buttons. There are a few exceptions, like some pedals by Bogner and Suhr, that have external switching input jacks. Those can be controlled by the PBC's function switches. But, most pedals don't have that feature.