People often post about getting PIN codes – here’s a nice link with information on what they are and how they work. http://thedisneyblog.com/2013/08/23/whats-a-pin-code/
What are the requirement to use a PIN code? If I rent DVC points to book a room could I still be eligible for free dining if I received a PIN code?
No - Pin codes are for standard bookings. Points renting never gets deals like free dining, as it is a marketing comic and from WDW’s point of view they have already sold that room to DVC owners.