基于USBTMC协议的USB接口虚拟仪器的研究-机械电子工程专业论文.docx

基于USBTMC协议的USB接口虚拟仪器的研究 Research of USB Visual Instrument Based on USBTMC Specification Abstract 讹ual instrument is a powerful and flexible integrated test．measurement and con仃oI system，which is composed of computer technology，application software and modularizafion hardware．In recent years，Visual instrument develops rapidly and is broadly applied．As a new bus standard in computer peripheral h抑dware，USB is adopted and widely used in visual instruments for its ease of llse，truc plug and play,power supply from bus，hi曲transmission speed，etc． Nowadays，USB Interface viSual instruments in domestic market are mostly developed by using general USB specification．k this way,developing USB visual instruments will expend long time，and interchangeability of products is bad．In order to solve these questions。USB organization issued new class specification--USBTMC(USB Test and Measurement Class)for USB intefface instruments．USB visuaI instrument,which accord with USBTMC specification． will be fully supported by visual instrument software，and users can easily develop instruments driver and application software by us纽g VISA(Visual Instrument Software Architecture)to improve the applicability of instnnnents on various opemtmg systems． This dissertation analyses the general USB specification，and focus on the research of USBTMC specification．An USB interface data acquisition card is developed．which is consisted of MSP430F169 and PDlUSBDl2and the fireware according with USFn订C specification is programmed．By researching the VISA and its connection method with USBTMC instrument through its cOiillnon interface functions，a program is developed in LabVIEW,which can communicate with USBTMC device through M-VISA． With the rapid development and popularization of network,visual instruments based oil network are widely used．After analyzing the structure and character of network-visual instrument,a network-temperature monitor system is built by using the developed USB DAQ card and the net funaion