Networked Virtual Oscilloscope Design Based On Labview

With the rapid development of electronic technology, computer technologyand information technology, people put forward higher requirements forautomatic test system, so high-performance modular hardware combined with aflexible and customizable PC software of virtual instrument technology arise atthe historic moment. The combination of virtual instrument technology andEthernet technology that realizes remote monitoring, data sharing, networkapplications, is the main development direction in the future.This paper has introduced the virtual instrument technology researchbackground and the research situation at home and abroad. The paper hasintroduced the protocols in the TCP/IP protocol stack structure and knowledgeof virtual instrument including virtual instrument hardware structure, softwarearchitecture, virtual instrument development environment. In the design ofNetworked Virtual Instrument Based on LabVIEW, it carried out the followingwork.Firstly, analysis and comparison of several embedded Ethernet solutions,determine the selection of C8051F040microcontroller and the CP2200Ethernetcontrol chip as the communication interface. And it has designde the EmbeddedEthernet interface circuit, which includes clock circuit, reset circuit, includingpower circuit and CP2200connected with the MCU main circuit. The interfacecircuit software program contain two parts; the first part, the driver of Ethernetcontrol chip CP2200is written, including the chip initialization, data framesending and receiving program; the second part, based on the analysis on theTCP/IP protocol stack and according to the protocol structure, working principleand actual demand, the paper designs the tidy TCP/IP protocol stack, andrealizes the data acquisition and Ethernet transmission function.Secondly, virtual oscilloscope based on UDP protocol is designed in theLabVIEW environment. Using the network communication module designs datareceiving and sending program based on UDP protocol; oscilloscope trigger control, timing control, parameter measurement, spectrum analysis, data storageand playback function and report printing function design process are detailedlydevoted. Ethernet communication function,and the basic function of traditionaloscilloscope are realizied.Finally, module software debugging and the actual operation of testinglaboratories are carried out. The Ethernet interface module program is debuggedin the Keil Vison3development environment. Virtual oscilloscope variousfunctional modules are debugged by using a detection tool in LABVIEW. Thelow frequency signal generator, an Ethernet interface module and virtualoscilloscope are tested, and the digital oscilloscope is connected to verifyexperiment results. The test results show that the designed virtual oscilloscopecan realize the designed function, and is up to the expected goal.