Design And Research Of USB Host System Base On ARM

Now, more and more embedded products have the function of USB interface. But in fact the function meant the subordinate machine .It can't recognize the USB device actively nor control or read/write it.The host (position machine) is in the key position of USB topology structure. Any USB data transaction must initiate and control by the host. So all the USB device must make connection with the USB host, any two devices or two hosts can't communicate directly. But now, mostly, PC play the role of position machine .All the devices can only be used on PC and all the files and data can only be transferred by PC. That's what the disadvantage.It's no use of PC if embedded USB host exists. The embedded USB host system choose Philips'LPC2210 chip as the CPU, ISP1161Al 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 system uC/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 and the expectant design intention was realized.