Design And Implementation The Embedded USB2.0 Host Controller Driver

Peripheral bus, which provides the interface for system host and devices, is one of the most important parts of embedded systems. Traditional peripheral buses are not applicable to embedded systems. The merge of computing and communication is the basis of USB design. The benefits of USB, such as high performance, ease of use, true plug and play, and reduced overall system cost, are just a few of the reasons this technology becomes more and more popular in embedded systems.The paper research into the design of embedded USB host, which includes hardware design, USB transfer scheduler degsign and the implementation of virtual root HUB driver.Firstly, the paper design the embedded USB host board based on ISP1760, which operate on XSBase evaluation board.The board design includes the interface of ISP1760 and PXA255, as well as the peripheral equipment of ISP1760.Secondly,the paper introduces basic concepts of transfer scheduling, scheduling rules in EHCI and embedded USB host, the operation modle of ISP1760.The buffer management of ISP1760, in company with scheduler and interrupt service routine, is being discussed. USB provides the interface for system host and USB devices. The USB host is dedicated to managing all USB device and transfer of the system.Thirdly,the paper introduces the enumeration in USB system and the concept of virtual root HUB.The virtual root HUB driver is being discussed.