Design and implementation of reconfigurable virtual instruments using Raspberry Pi core

Virtual Instrument is a combination of hardware and software that allows the emulation of an instrument through a custom virtual console and a graphical user interface. A virtual instrument consists of a PC equipped with powerful application software, cost-effective hardware such as plug-in boards, which together perform the functions of traditional instruments. In a virtual instrument, it is the software which performs the actual process of measurement. Using virtual instruments one can design a customized instrument and automation setup that is user-defined instead of being limited by traditional fixed-function vendor-defined instruments. Virtual instruments are not efficient systems to handle time critical instrument tasks since they are run by a PC operating system which introduced substantial timing errors into the measurement. The Reconfigurable Virtual Instrument (RVI) system can be considered as a general purpose measurement instrument designed with reconfigurable hardware like FPGA connected to PC through a standard port. By designing a high level software application, one can select any specific instrument functionality from a library of instruments. The high level software application configures the RVI system to convert it into the selected instrument(s) with its associated console. By this technique, one can emulate multiple instrument functionalities like function generator, oscilloscope, multimeter, logic analyzer in a single hardware platform. In this paper, hardware realization of RVI is done using FPGA and Raspberry Pi core.