Development Of High-Speed Data Acquisition Vxibus Module

As the increase of the social digital degree, the high-speed data acquisition is very important in the field of measuring and controling. The test platform based on VXIbus is the leading technology in the field of test instrument; it can easily construct the automatic testing system. VXIbus's modularization, high speed, high reliability and high data throughput features make it widely used in the whole world. The research task of this subject is to develop high-speed data acquisition module based on the VXIbus. The acquisition and control circuits, which are the core of Digital Storage Oscillocope, are assembled on the module, and make it suitable for DSOs based on the VXIbus. For high speed data sampling and processing, with constant increasing of data quantity and constant inprovement of real-time processing request, we have proposed using DSP to carry on data processing, in order to improve systematic real-time feature and ability of the fast data store. This paper researched the way of realizing two-channel high-speed data acquisition based on VXIbus which taked advantage of DSP, CPLD and some other technology. The sampling rate of the module can up to 200MSa/s, with 8 bits vertical resolution, with 32M of storage depth, can realize several kinds of trigger mode such as instantaneous triggering, Post-trigger or Pre-trigger and software trigger.this paper discussed the designing of the circuit of modulating the front-end signal, of A/D converting and of transferring detailedly; designed the control logic of the module and the interface of VXI with CPLD; descriped electromagnetic compatibility and the circuit which realized it; the software flow is centered on DSP, designed the PCB board according to electromagnetic compatibility, and at the end of this paper, some problems, which are encountered in designing, debugging and simulating process, are presented and the solutions to them are given. The content of this paper has some important reference value for the high-speed data acquisition of PXI, PCI module, DSO and some other researchings on high-speed data acquisition.