First of all, no you can't program the tivo peanut remote to control a Hr20/Hr21, sorry. The tivo codes in the white remotes are 01442 & 01142, and tivo codes only found on the av1 or av2 devices include 20618 & 20739. These codes are address zero, so they will control all your peanut remote controlled tivos no matter what address they're set to, so there is no way to control more then one tivo independently, sorry. The difference between code 01442 to code 01142, the code 01442 has the exit command on the EXIT key, where code 01142 has the clear command. Code 01442 also has the LIST command. There won't be a command mapped to the power keys using codes 01442, 01142 and 20618. Just like the tivo peanut. But code 20739 has the standby command mapped to the middle power key in the av1 or av2 device its programmed to. If you have any other tivo questions regarding the white Directv remotes ask here.