基于TMS320DM642的LXI通用接口板研制-仪器科学与技术专业论文.docxVIP

Abstract LXI bus technology has been widely applied to the test instrument, so as to constitute an internalized and distributed test system. LXI instrument is composed by the LXI interface and functional circuit. In order to speed up the development efficiency, the common LXI interface board based on the DM642 is developed and combines it with functional board, different LXI test equipment is pro duced. And DM642 under the DSP / BIOS operating system can easily access to the rich peripheral resources, making it easier to develop the functional board driver compared to the traditional design. In-depth analysis of the subject on the basis of functional requirements and technical specifications, system hardware and software design is put forward. Taking TIs high-performance digital signal processor TMS320DM642 as the core of hardware, the hardware circuit of the Class A LXI instrument interface is designed and divided into the CPU and peripheral circuits, network communication interface, the real-time clock interface, the hardware trigger interface and function expansion interface. In software, the TIs embedded real-time operating system DSP/BIOS is embedded and the designations of LAN communication, the Web server, LAN discovery, the IEEE 1588 Precision Clock Synchronization and guiding power of DM642 are completed. In LAN communications, Network Development Kit (NDK) is transplanted and network communication program is designed; the enable of HTTP service of the NDK, web document preparation, conversion and loading and CGI written in response is introduced in the Web server part; on the basis of a careful study of the VXI-11 protocol in the LAN discovery part, a port mapping program PORTMAP and RPC server program is designed; in the precision clock synchronization part, the DP83640 and PCF8583 driver are designed first, andthen PTPd1.0 is transplanted and improved, thus achieving clock synchronization and a higher synchronization accuracy; finally the power of the