The lessons

Taking a game apart tells us what it does. A lesson is the other half: a small cartridge of our own that does the same thing, written from what we measured and measured again the same way, so the two can be set side by side. Its program is ours, so it is shown whole, and the cartridge is yours to play.

• A jump that feels like Mario's: A cartridge of our own whose square walks and jumps with the numbers read off Super Mario Bros., measured beside it, with its program. Our own autopsy, run over it, names: The poll, The wait for the frame, The picture writer, The palette writers, The sprite writers, The scroll writer.
• Rooms that slide in the way Zelda's do: A cartridge of our own that holds the picture still and slides the next room in when the square walks out of one, the way The Legend of Zelda was measured doing it, measured beside it, with its program. Our own autopsy, run over it, names: The poll, The wait for the frame, The picture writer, The palette writers, The sprite writers, The scroll writer.
• One byte chooses the screen, the way Mario's does: A cartridge of our own with a title, play and a pause chosen by one byte through a jump table after a call, the way Super Mario Bros. was measured choosing its screens, and what our own autopsy says of it. Our own autopsy, run over it, names: The poll, The wait for the frame, The jump engine, The picture writer, The palette writers, The sprite writers, The scroll writer.
• A picture that scrolls the way Mario's does: A cartridge of our own whose picture follows the square and builds the land ahead in strips, the way Super Mario Bros. was measured doing it, measured beside it, with its program. Our own autopsy, run over it, names: The poll, The wait for the frame, The picture writer, The palette writers, The sprite writers, The scroll writer.
• A stomp and a hit, told apart the way Mario does: A cartridge of our own where touching a walker from above, falling, flattens it and bounces, and any other touch is a hit, the way Super Mario Bros. was measured telling them apart, measured beside it, with its program. Our own autopsy, run over it, names: The poll, The wait for the frame, The picture writer, The palette writers, The sprite writers, The scroll writer, Where two things are compared.