Software Design Of Large Scale Matrix Switch Based On LXI Bus

The introduction of Ethernet technology into the instrument industry has brought about the emergence of the Lan Extensions for Instrumentation(LXI)device.In the Automatic Test System(ATS),the switching subsystem’s probability is second only to that of the system controller.The domestic research and development of matrix switch products attaches a low degree of importance,and there are problems such as small switching scale and slow switching speed.Therefore,the development of large-scale high-performance LXI bus matrix switch is of great significance for the construction of an automation test system.Based on the LXI bus standard,Thesis uses the matrix switching equipment as the verification platform to discuss in depth how to design and implement the large-scale matrix switch software that meets the LXI C standard.The main content of this thesis is as follows:1.Starting from demand analysis,combined with the LXI instrument specification and the hardware design of matrix switch to complete the overall solution design of the software.At the same time,the system uses the Longxin 2K1000 development board as an embedded platform and transplanted the Neo Kylin desktop operating system.2.Implement the LXI bus C type protocol.This embedded controller was constructed with the help of Remote Procedure Call(RPC)technology and the VXI-11 protocol,thus enabling the construction of the RPC server,VXI-11 protocol specification,and web server.This enabled the realization of the LXI bus-based network discovery mechanism.3.Based on the function of the matrix switch,the format and characteristics of the grammar in the specifications,the Standard Commands for Programmable Instruments(SCPI)program-controlled command set was designed,and completed the design and implementation of the command parser.4.By analyzing the layout of the instrument hardware relay,based on the layout characteristics and actual use,a self-inspection program that is simple,economical,and small as possible is designed to achieve the functional detection of thousands of relays inside the entire device.5.The function of the browser webpage access instrument is implemented.The web server and the Hypertext Transfer Protocol(HTTP)was analyzed,and related web pages were designed according to the LXI instrument standards,realizing the webpage access to the matrix switch device.6.Complete the Interchangeable Virtual Instrument(IVI)driver and direct I/O driver on the domestic operating system,and realize the design of upper computer software based on IVI driven and direct I/O drive.Thesis has completed the software design of the large-scale matrix switch,which enables the instrument to have the functions that meet the LXI C standards,and test and verify the functional modules of each part of them.The test results meet the requirements of the subject.