Charter All Digital WI

Hi. So Charter has gone all digital in my area of Wisconsin. We have a few TVs in the house and mine is the only one with a Tivo. My sister is the main person on the account and she doesn't really understand the whole Tivo thing and forgets I have it. They have an HD box upstairs in the living room that still works since the digital switch I believe. They got a different box for the basic TV in the bedroom. Tonight her boyfriend brought me a new HD box so that I can still get cable. Well right now I don't think my HD box is activated anyways but there is no way I can use it with my Tivo correct? Do I need a CableCard or some other box? Right now I just have my Tivo set up on AV2 so that I can at least watch my recorded shows.