Development Of LXI Universal Board Based On TMS320DM642

LXI bus technology has been widely applied to the test instrument, so as toconstitute an internalized and distributed test system. LXI instrument is composedby the LXI interface and functional circuit. In order to speed up the developmentefficiency, the common LXI interface board based on the DM642is developed andcombines it with functional board, different LXI test equipment is produced. AndDM642under the DSP/BIOS operating system can easily access to the richperipheral resources, making it easier to develop the functional board drivercompared to the traditional design.In-depth analysis of the subject on the basis of functional requirements andtechnical specifications, system hardware and software design is put forward.Taking TI’s high-performance digital signal processor TMS320DM642as the coreof hardware, the hardware circuit of the Class A LXI instrument interface isdesigned and divided into the CPU and peripheral circuits, network communicationinterface, the real-time clock interface, the hardware trigger interface and functionexpansion interface.In software, the TI’s embedded real-time operating system DSP/BIOS isembedded and the designations of LAN communication, the Web server, LANdiscovery, the IEEE1588Precision Clock Synchronization and guiding power ofDM642are completed. In LAN communications, Network Development Kit (NDK)is transplanted and network communication program is designed; the enable ofHTTP service of the NDK, web document preparation, conversion and loading andCGI written in response is introduced in the Web server part; on the basis of acareful study of the VXI-11protocol in the LAN discovery part, a port mappingprogram PORTMAP and RPC server program is designed; in the precision clocksynchronization part, the DP83640and PCF8583driver are designed first, andthenPTPd1.0is transplanted and improved, thus achieving clock synchronization and ahigher synchronization accuracy; finally the power of the DM642boot loader isdesigned, leading the interface board to be powered and be an auto-loader withoutemulators.In the last step, the interface board undergoes detailed tests, and each functionruns well, achieving the design specifications in full compliance with designrequirements.