Based On Ivi - Com Lxi Digitizer Driver Design

With the rapid development of automatic test systems, The hardware replacementand upgrade in the automatictest system requires huge software update cost. Theinstrument driver technology is put forward to solve this problem. Instrument drive isthe important component of the virtual instrument, it provides moresenior, and usefullprogramming model. It can control and test the instrument through the simple functioncall way, which have many advantages, such as high performance, instrumentsimulation, instrument swaps, flexible development, and so on. IVI technologycombines the COM and IVI technology, it puts forward the virtual instrumentdevelopment platform through the use of the COM technology. So that when takereplacement of equipment, it needn’t change the original test program, and also don’thave to recompile or link, and even can be done with out interruption between theswitch of the same type equipment. Through this way, it solves the problem of thesubsequent cost and the general use of the instrument drive brought by there placementof equipment. IVI-COM driver is becoming the main stream mode of thedevelopment instrument driver. LXI instrument will be the current and future testarchitecture because of the advantages in the network, open, modular, andinteroperability. Emerging LXI instrument drivers must comply with the IVIspecifications. This paper takes the example of LXI-C oscilloscope module, andcomplete the IVI-COM instrument driver development work in the Visual Studio2005environment. Firstly, paper studied the key technology based on LXI digital instrumentdrive, such as LXI technology, IVI technology and COM technology, include theclassification of the instrument driver and the design of the function group in thecomponent object model and IVI specification, but also some part of relevantstandards in the LXI instrument driver program. Based on the the oretical basis, thispaper gives scheme design on the instrument driver program. It starts from externalinterface model, the internal design model of the instrument driver and the architectureof IVI-COM. Then extract simple mentation principles of the interchangeability between the IVI-COM instrument driver, especially describesa key role part(such asIVI configuration, IVI call factory and so on) in detail and make a realization.According to the hierarchical structure of the IVI software system and the developmentprocess of the LXI digital instrument driver, this paper do some detail work in thebuild of the architecture, the design of the interface level and the realization of theinterface functions, especially make some research in the key realization of themethods and attributes. Finally finish the LXI digitizer driver based on the IVI-COM.In order To make paper content more intuitive, more fully in theoretical basis, andmore distinct paper level, this paper also introduces the class figure of the oscilloscopeclass IVI-COM driver, basic behavior model, and its internal working theory principle.Practice has proved that IVI-COM instrument driver can well realize theinterchangeability of the instrument and the reuse of the test program.