Replacing a Panasonic Doorphone

I just installed a Ring Doorbell (model "1"), to replace a Panasonic KX-T30865-B Doorphone that is connected to my Panasonic KX-TA616 PBX.I want to know if I can just hardwire my new Ring to the 2 wires that run from the PBX to the Doorphone as if it were a digital/mechanical bell (as the manual indicates) and avoid recharging the battery every 2 weeks.Since the existing wires use to carry both voice and the signal created by the button when pressed (it's not a simple transformer to bell circuit) , I'm not sure it it carries the desired voltage or whatever is needed to function properly.Thanks.