Six Channel 16 Bit PXI Acquisition Module Software Design

In the modern industrial test, the multiple point sampling synchronization and signal acquisition speed are increasingly high demanded. This often requires a plurality of channels acquisition modul, which is able to achieve data acquisition,real-time processing and display. To develop virtual instrument data acquisition modules which have multi-channel, real-time display capability has becoming an urgent need. The trend of development of the instrument software, due to the large capacity storage and limited processing capability of the hardware, the development cost is higher.This project develops six channel acquisition module software based on PXI bus, which make full use of computer resources, making the acquisition, storage, processing of the data by the software running in the computer to complete, and achieve the goals of implementation six channel synchronous displaying. This enhances the acquisition module of data processing and storage capacity and greatly reduces the cost of development.This paper focuses on the implementation of multi-channel data acquisition module software.Through the analysis of the hardware platform and target task,I design the whole scheme of software,which includes the instrument driver and the man-machine interface of the exchange of two parts. Finally,I take a corresponding test on the software function. The main research contents are as follows:1.The man-machine exchange interface program designs the main interface which achieve the six channel display, for the corresponding channel control and real-time waveform display. Designing for instrument interface and cursor measurement interface,parameter setting interface auxiliary interface to complete the corresponding instrument search, parameter setting, real-time processing of waveform parameters.In the whole design process,through each channel package into the corresponding classes, each functions of the acquisition module for the software module, which is convenient for the following procedures to upgrade and maintain. In the design of the multi thread technology to realize multi channel synchronous sampling and continuous display.Through the smoke point difference algorithm for data processing.Refresh graphics using double buffering technology, improve the running efficiency of the program.2. The instrument driver based on IVI specification is design Which packageinterface function corresponding function for the implementation of communication with hardware. The receiving parameter information which the man-machine exchange interface program settings,Converted into the corresponding command which is sent to the corresponding FPGA port, to complete the corresponding control channel, trigger function set and the implementation of the channels of different sampling methods.Acquiring data from hardware through the PXI bus, to transfer data to computer exchange interface program.At the same time, the calculation parameters of waveform data according to the corresponding algorithm.3. Finally, through the joint commissioning with hardware and test each function part. The acquisition module is capable of multi-channel analog input signal synchronous real-time acquisition and display, control of the corresponding channel,realize the triggering function of the channel. has the ability to analyze the waveform.At the same time, the file system design of synchronous sampling technique and data processing optimization better realization of rolling large capacity data storage,waveform display. The friendly man-machine interface and convenient operation and expansion, convenient for the user to use. Software design meet the requirements.