This unique guide goes beyond all the Universal Serial Bus (USB) specification overviews to provide you with the expert knowledge and skills you need to design and implement USB I/O devices. It is organized around a series of fully documented, real-world examples, and is structured to serve as both a step-by-step guide for creating specific devices and a complete reference to USB. Design examples cover most USB classes (HID, communications, audio, mass-storage and hub) and provide insights into high-speed USB 2.0 devices, including a definition and a device driver for a vendor class, called blockio.