I have a Roomba model 4210 discovery that do used in the tutorial. Do I only need to apply power and it comes on ordo iI need to press a button each time to prepare for a connection to ezb. If I must press a button each time I can't see the Roomba being a useful base for beer robot unless just use the motors and case and remove everything else. Can someone verify this? The Roomba I have is already modified for external power.