Research And Design Of Embedded USB-HOST

The USB standard is one kind of new serial main line which solved the insufficient bus unit. In the early time computer system often uses the serial port or the paralle connecting with the peripheral equipment, these connections usually link between point-to-point, and a interface corresponds an equipment, the interface expands must increase the corresponding connection card to support, USB arosed along with those all sorts of limited existence.Presently,USB standard has been applied widely in the migrationdata exchange and the memory,because it has many characteristic, such as it speed quickly, installment simply,the connection easy, support hotly inserts , takes the main engine resources few, and easy to expand and so on. It has facilitated people's life, make the data exchange transportability and conveniently, at the same time stimulated the IT industry development. But these applications usually realizeb by the general-purpose computer, namely must carry on the data through PC machine to alternate, and that it is unable realize alternation and control freely between the different USB component. Along with USB applied domain gradually expansion, more and more people are also higher to the USB expectation, hope the USB can apply the non-PC domain. For example in the data acquisition system, use USB to move the storage device stored datum under the labor controls platform, the expansion capacity.Inserts under the typeplatform in each kind directly to use the USB connection the application equipment to expand the connection and the convenience operation.Therefore, the inserted USB main engine system the research to comply with the IT industry development, has further manifested the data exchange mobility and the convenience, had the practical valueand the significance. If applies to the digital camera, may expand orthe direct drive USB printer printing photograph as the memory. The paper system analysis and introduced the USB interface standard. Hasstudied based on PC platform Windows the system USB agreement stack realization way.According to inserts the type system the characteristic, established has inserted the type USB main enginesystem model based on USB OHCI, has realized HID in this foundationkind and Mass the Storage kind, confirmed has inserted the type systemto turn on the HID kind of mouse equipment, in the resourcesrelatively limited inserted on the type system to realize to USB Massa Storage kind of equipment (the U plate) the read-write control,among, but also the detailed research and has analyzed the FAT filingsystem. Finally, has forecast the USB connection development questionand the direction.