The Design Of Embedded Data Acquisition System Based On Virtual Instrument

With the development of the computer technology, microelectronics and embedded technology,the instrument industry is developing towards the virtual instrument, which makes the virtualinstrument technology and embedded technology more and more closely. Based on the virtualinstruments, embedded application and data acquisition technique, a design of the embedded dataacquisition system based on virtual instrument is presented in this paper.Firstly, the overall design of this system is introduced, and we select the embedded processorPXA270and Windows CE as the hardware and software platforms of the embedded systemseparately. FPGA is used as cybernetics core of the data acquisition system, and the main chipselection of the data acquisition module is introduced. Besides, we select the Embedded Visual C++and LabVIEW as the application development tools in this paper.Then we analyze the data acquisition module in detail. The design of the data acquisitionsystem is divided into the front-end conditioning circuitry, the AD converter circuitry, the PC104interface circuitry, the memory controller circuitry and the control program for FPGA. The parallelsampling ADC system is used in this paper so that we can get a high sampling rate.In the section of the embedded platform, the hardware resources of the master platform and theallocations of static storage are introduced separately. The property and transplant of the WinCEsystem is analyzed, and the drivers and dynamic link library are designed for the data acquisitionsystem. The design uses the Embedded Visual C++and LabVIEW development tools to develop thevirtual instrument, the human-computer interface are both friendly. We use the stub call method tosolve the cross-platform problem of the compile and run environment of the embedded LabVIEW.And we realize the application development for LabVIEW in the WinCE embedded system. Signalprocessing functions, such as spectrum analysis and digital filtering, are designed in the applicationdevelopment by LabVIEW.In the end, the debugging and experimental verification of the system are carried out, and wemake a comparison of the two development tools.