Comment by nickmqb

Yes and no. The design includes a custom built 16-bit CPU, which uses a custom instruction set, which I wrote an assembler for. There is a small 4kb bank of RAM that contains a program written in this instruction set. From a hardware perspective it is just data, but from a a software perspective it's that program that is ultimately responsible for running the game (by reading input from the gamepad module, setting up GPU registers, etc.).