Research On Multibus Instrument Programmable Interface Converter Development

This thesis is derived from the institute of scientific research project "research on multibus instrument programmable interface converter". The current semiconductor test circuit production lines of the institute are of old and new equipment,together with various GPIB, LAN,USB bus interface types.This leads to difficulties in unification of test platform, and have a great impact on ease of use and stability of the automatic test system.In order to solve these problems,this project aims at developing multibus instrument programmable interface converter and realizing USB/LAN-GPIB bus interface conversion.The project will bring practical value to science and development testing of the institute.Currently, the institute the author works in is facing the following problems, co-existence of new and old equipments in semiconductor test circuit production line; GPIB, LAN,USB equipped for all kinds of instruments are too complicated to unify. So the reasons for selecting this topic are due to difficulties for unification of testing platform as well as negative influence to the stability and operation ability of automation testing system of the author’s working unit. The realization to this relies on development program interface converter, in order to realize USB/LAN and GPIB convertion,which can bring higher practical value to the working unit.The relatively mature USB/LAN- GPIB interface conversion solution in China and abroad, such as USB-GPIB interface converter and LAN- GPIB interface converter type of products are still relatively few and expensive. For example, Keysight Technologies co.LTD’s(formerly Agilent Technologies co. LTD) USB-GPIB interface converter 82357,LAN-GPIB interface converter E5810 A, as well as the National Instruments(NI) of GPIB- ENET / 1000 and GPIB- USB- HS interface converter, the interface converter prices are in the range of $500 to$1000(about ￥3000 to ￥8000. In addition, the above products of foreign company can only realize single two interface conversion function, it cannot achieve a variety of interface to the GPIB interface conversion functions, forming the automatic test platform to field test in the practical application, such as is not convenient to use and carry. Besides that, at present domestic manufacturer of research and development of similar products are also more than basic to reverse the company products, poor stability and no intellectual property rights. Therefore, independent research and development of USB/LAN to the GPIB bus interface converter can save research funding, it can also avoid intellectual property problem.The research purposes of the research project are to achieve the development of the USB/LAN to GPIB bus interface converter design, implement and control machine through the USB/LAN bus interface and build a smooth communication between instrument GPIB bus interface. Furthermore, the products out of the design are of lower price, higher functional integration and fulfillment to all demands of testing production line and field experiment.This paper discusses the USB/LAN- GPIB interface converter basic design principle and overall design scheme of hardware and software design. Using single chip microcomputer STM32F407 design USB/LAN-GPIB interface converter, is the instrument with GPIB interface programmable via USB, or LAN interfaces are connected to the measuring machine, the converter is using a standard USB interface, a LAN interface, GPIB interface, through the converter, with the above standard bus interface of programmable instruments,it can easily accept control machine control, or connected to the GPIB automatic testing system.Hardware: combined with the purpose of this study, the device performance and price, as well as the degree of familiarity with the existing hardware and software resources factor, determines the converter based on single chip microcomputer STM32F407 hardware design scheme.STM32F407 integrated USB interface controller and USB- FS(full speed) PHY, realization of USB- HS(high speed) interface to external high-speed PHY circuit, this design USES the USB interface- the HS.STM32F407 integrated 10/100 MBPS Ethernet controller, but external fast Ethernet PHY can realize network function. This design chooses DP83848 as the network physical layer chip. GPIB interface circuit module is mainly controlled by GPIB interface chip NAT9914, bus transceiver SN75162 and GPIB standard connectors, etc. Software: converter software to write and compile environment for Keil uVision5.In ST’s Cube library based on the USB- TMC protocol, TCP/IP Lw IP protocol used to wrap.In this project, the author completed the USB/LAN- GPIB programmable interface converter design of software and hardware, realized the control machine and the programmable instruments online debugging operation via the USB/LAN-GPIB programmable interface converter; operated the programmable function of measurement and control machine of program-controlled instrument,reached the expected development target of this project.