Research And Realization Of Embedded USB-HOST

In the process of the modern technology developments, with the rapid developments of the processor technologies and embedded applications such as communication products, electronic consumer goods, etc. the embedded system all is available in peoples' lives. Among all kinds of embedded products, data transfers usually are completed by some interface.Among the early PC system interfaces, there are many kinds of interface such as serial interface, parallel interface, and PCI interface etc. Because there are low data speed, hardness to switch, and difficult operation etc, as a result, USB is present.Now, in the embedded system of signal and data collection, the data switching is completed by floppy disk, serial interface, or ethernet etc. As a comparison, USB available in the embedded system slowly take on advantages of operation. But almost all USB interface is based on PC, so the reseach of embedded USB is valuable, in specially, of the USB host interface as master.The main part of this thesis goes back the history of USB firstly, then analyses the USB 1.1 specification completely, and compares the difference and realization of the USB stack in the PC, in the embedded system based on OS, and in the embedded system base on no OS. As a result, the experiment model with USB host interface based on no OS in the embedded system is set up. On the model, HID class (USB mouse) and mass storage class (USB flash disk) is implemented and validated. Among the process of the research, the FAT file system is fully researched as well. At the same time, a lot of lab analysis is taken on the model built by myself. Based on the records of experiment, the qualitative analysis of the USB interface and USB stack response the differences in the different embedded system. At last, in the last part of this thesis, the further researching of USB and some later problems are also discussed...