I was wondering if anyone knew the length of the timer that runs in OBD2 in order for it to go closed loop?

And also if this goes for all OBD2 computers, or if it would be manufacturer specific.

If anyone knows a website that would have this kind of information, I would like to have some proof. Its for a test question that I dont agree with, it stated that every OBD2 computer has a 1 minute timer that must expire before closed loop can occur.