Yes - you can play on both PC and PS3 using the same SE Service account. If you've purchased the game of PSN store there is no "registration code" - it's part of your purchase / download list. If you haven't played the ARR on your PS3 first you need to (re-)download it from your PSN download list and after the first run link your PSN account with your current Service Account you're using to play on with PC version. DO NOT (by mistake) create a new Service Account while linking your PS3 / PSN account to SE otherwise you'll be unable to play with the same character and using the same subscription as on PC. This asumes that you play currently on PC, have purchased in the past the PS3 version as well but haven't used it yet. In short - you need to purchase the copy of the game for each system and have both versions registered to the SAME SE Service Account.