The tutorial is split into three sections. I strongly advise you go through the tutorial in order!
In Part Ⅰ, we run our first “Hello World!” program, which we then dissect to learn what makes the Game Boy tick.
In Part Ⅱ, we program our first game, a clone of Arkanoid; we learn how to prod the hardware into having something we can call a “game”. Along the way, we will make plenty of mistakes, so we can learn how to debug our code.
And finally, Part Ⅲ is about “advanced” use of the hardware, where we learn how to make even better-looking games, and we program a Shoot ‘Em Up!
Unfortunately, this tutorial is a work in progress. Currently, Part I is being written, and Parts II and III should follow soon after.