Well, I said upfront that the level of comments here is fine. Just offering a perspective on how it could still be good code with less. In general I think it's fine to expect a reading of the code to be paired with a reading of the documentation/specification; in the absence of such a resource for the GameBoy the comments here are well-justified. I would definitely add more constants, though, and I would anticipate that a second implementation which references this would start by re-defining all of the constants in its own code.
Most people will argue that this is nitpicking, however, I've learned something new today. Thank you.
Quite a difference in code readability to the point where the code becomes self-evident. Few people are able to reach a more verbose level of documentation, let alone make sure the code remains understandeable in the future.
