Thank you Jelydonut and ntxp for your comments,
I'm just curious about this chip. About one month ago, I made a copy of my DVD player's rom image and found out that there is a menu (hex codes) that can unlock zone restriction and many other features. I want to access this menu. I was not able to do anything since I don't know the instruction set of this chip. Maybe, you guys can give me a way to access this menu without having to know the instruction codes.
Regards, Dspnut