Digital Electronics: Principles, Devices and Applications

700 Digital Electronicsetc., are the commonly used ones. One or more of these building blocks are invariably found involtmeters, oscilloscopes, spectrum analysers, waveform analysers, counters, signal generators and soon. In an instrumentation set-up comprising more than one instrument function there is therefore likelyto be lot of redundant hardware.A fast-emerging concept is to have instrument hardware in the form of building blocks thatcan be configured from a graphical user interface (GUI) to emulate the desired instrumentfunction. These building blocks could be reconfigured at will to become voltmeters, oscilloscopes,spectrum analysers, waveform recorders and so on. A graphical panel would represent eachvirtual instrument.16.19.2 Components of a Virtual InstrumentThe basic components of a virtual instrument as shown in Fig. 16.40 are the computer and display, thesoftware, the bus structure and the instrument hardware.16.19.2.1 Computer and DisplayThe majority of virtual instruments are built around personal computers or workstations with highresolutionmonitors. The chosen computer should meet the system requirements as dictated by thesoftware packages.16.19.2.2 SoftwareThe software is the brain of any virtual instrument set-up. The software uniquely defines the functionalcapabilities of the instrument set-up, and in most cases it is designed to run industry-standard operatingsystems for personal computers and workstations.DisplayComputerInterfaceBusInstrumentHardwareSignalsSoftwareFigure 16.40Components of a virtual instrument.