Design And Implementation Of Embedded Usb Host System

The Universal Serial Bus is a new technology for connecting peripheral devices to computer. Compared with the traditional PC interfaces such as serial and parallel port, the USB combines the advantages of higher data transfer throughput, plug-and-play, hot swapping, expandability and low-cost. It's not long before the USB has become the requisite standard interface in PC after the USB specification was issued.With the popularization of the USB interface, a lot of embedded applications start to think integrating USB port into systems. One part of the applications is designed as PC peripherals, the other is designed as USB host in order to use the peripherals. The USB host takes up the core position in the USB system architecture. Each USB data transfer is initiated and controlled by the host. Every USB device can only connect to the host and can not communicate with each other directly. The embedded USB host technology will solve the problem that embedded systems are not able to make use of USB devices.To begin with, the thesis presents an overview of the universal serial bus specification, then introduces the basic knowledge of the USB protocol. Next, the whole procedure of research and development of the embedded USB host system is fully described, including hardware designing and software programming. At last, this document illustrates how to fulfill the USB device class program with a real engineering project in which a USB printer is the target device to be used.