I remember a few years ago I went to a party and ended up talking to Mar about how much I hated Chapter 9 of the USB standard. USB is pretty much a perfect example of what happens when committees design protocols: its bad enough that it will ruin a party. If you’ve ever had to design a driver or device you probably know what I mean. Well I recently found the “USB Made Simple” page, which seems to be a nice companion to the (incomparably useful) Jan Axelson material.
Anyways, I like how this page has lots of diagrams!