Research On Embedded USB Host System Based On ARM

With the development of PC peripherals and digital products, the interface and connection between any two of them have become a difficult problem. USB has been extensively adopted as a bus interface technology in PCs today. People hope to use USB devices in some embedded systems, but the kernel of USB topology is PC and USB devices cannot use without PC. All the devices can only be used on PC and all the files and data can only be transferred by PC.This is very regrettable.For example, in an industrial area of the data collection,as the portable storage device embedded in general is very limited,always need to use USB Flash Disk as a USB data storage carrier.In this Paper the design and implementation of the hardware and software on both host and device sides are demonstrated based USB protocol in details. According to the design request, the USB1.1 specification is analyzed in this thesis, in which, put the emphasis on the USB system architecture, data communication model, data packet format, USB standard descriptor.Secondly, on the basis of analyzing the USB device Mass Storage Class speciation, the logical communication model between host and device is established.The embedded USB host system choose Philips LPC2210 chip as the CPU, ISP116lA1 as the host control chip.The hardware design of the system mainly describes the chip chosen and circuit design. In the software part, embedded operation systemμC/OS-II was transplanted; the USB host control drive, USB drive and the user software are completed so the enumeration and the configuration of the device can be done. The written and read of the USB flash disk is realized by sending UFI(USB Floppy Interface)command over the interface with file system based on Mass Storage Protocol.According to the method mentioned in the Paper, the USB host system was constructed.