Well, there is nothing in the PSP that can stop it from reading 256gb. I know the PC is showing it as full 256gb when you format it there but i'd be willing to bet that if you actually tried to write 256gb to the card, at some point it would it screw up. It all points to a faulty adapter.
Thing is, ALL the CR-5400s are fake these days, I don't believe the legit ones are in production anymore. Its just a case of finding one that does work unfortunately. But in my experience they all do, so perhaps you've just gotten unlucky.
EDIT:
Oh! I have no idea why that sorted it lol
Thing is, ALL the CR-5400s are fake these days, I don't believe the legit ones are in production anymore. Its just a case of finding one that does work unfortunately. But in my experience they all do, so perhaps you've just gotten unlucky.
EDIT:
Oh! I have no idea why that sorted it lol