Based On Parallel Alternate Data Acquisition System Of The Virtual Oscilloscope

Virtual instrument is becoming high-tech product with the developing of the computer science and the modern measurement technology. It is the instrument that depending on a software, controlling hardware with computer, analyzing and providing the testing data. Virtual oscillograph is one kind of virtual instrument, This text has recommended the whole course of the developing of the virtual instrument.The virtual oscillograph is made up of the hardware platform and the computer with testing software, it is a powerful signal processing system. It can realize the function of the traditional oscillograph but also can store, reproduce, analyse and deal with the waveform. It is high speed, portable, and multi-functionalling. The virtual oscillograph designed this time has the following characteristics:1, Using interleaving/multiplexing technique, breaks the limit of the performance of a single A/D converter.2, Adopting the popular USB interface technology, make the virtual instrument and interface of the computer more convenient, communication is higher in speed.3, Using labview graphic language to design the application program of the host PC, not merely realize that the waveform shows, and deal with the data analysis.The whole paper introduces the back ground of the virtual instrument and current situation of the virtual oscillograph at first, then carried on the systematic demand and analysed and designed overally , following, designed the interleaving/multiplexing data-acquisition circuit and the time division data-storing circuit. designed the USB interface circuit. In software designing aspect, this paper introduced USB firmware programming method and the driver design. And using labview graphic language to design the application program. And at the end summarized and looked into the distance to originally designing finally.