I just found out the hard way that the Intellivision II console was designed to deliberately prevent Coleco-manufactured cartridges from operating on it. According to Intellivision Lives, Coleco eventually figured out a way around this, incorporating the workaround into subsequent releases of titles like Donkey Kong, Venture etc.

Given that none of the Inty Coleco-made games in my posession seems to work in my Inty II, I'm wondering if there's some way of distinguishing the compatible from the non-compatible? I'm looking to get rid of my Intellivision I and just keep the II but don't want to be stuck with a particular system that can't play some titles, or conversely titles that can't play on a particular system.