Research Of Data Acquisition System Based On Universal Serial Bus Host

USB(Universal Serial Bus) technology is being developed at full speed. USB Specification 1.1 updates to USB Specification 2.0. Transfering speed of devices which is the most important guide line of USB Specification is enhanced from low speed of 1.5Mbps and full speed of 12Mbps to high speed of 480Mbps.In general, USB system includes two subsystems: USB host system and USB slave system. At present, the technology and development of USB slave system have been already very mature. And all kinds of USB slave devices have been very popular. USB host system always base on the PC (Personal Computer). However, implements of USB host system based on embedded system encounter many difficulties because of abundant resources on the PC and limited resources on the embedded system. But embedded USB host system has fine application prospects in the fields of data store and data exchange.In the dissertation, the opology and correspond of USB syetem is analyzed detailedly. And USB host system is applied to Data Acquisition System, and a Data Acquisition System based on USB host is formed. In the design of hardware, single chip processor C8051F021 of Cygnal is adopted as the CPU of USB host system, and SL811HST of Cypress Corporation is adopted as the interface chip of system. And the keys of the software are realizations of USB Specification 1.1, Mass Storage Class Specification and FAT File System. These three parts, adding the data acquisition program and client application program, form entire software system.The testing and debugging to the system indicate that the hardware of system is up to the mustard completedly and the software can implement part function, which can be predigested and explored. The whle system have some specialties: simpleness, speediness, convenience and so on. And the system has fine application prospects.