DSP Implementation Of Virtual Instrument

Virtual instrument (VI) is composed of computer, escpecially designed hardware and software. It takes advantage of mighty graphic setting and on-line help of computer. The control panel of VI, which accomplishs the date analysis and date display, is established on the computer. The instrument function can be set on computer, and it can be achieved in the instrument hardware in time.The VI in this paper is implemented on DSP. There are many advantages in this VI: (1) The C54xDSPs use an advanced modified Harvard architecture that rnaxi mizes processing power with eight buses. Separated program and data spaces allow simultaneous access to program instructions and data. (2) there is an on-chip timer in the DSP. User can set the tinier precisely through control program. In order to make full use of powerful real-time processing ability of DSP, Some improvements involved in function generation algorithm have been obtained. An optimized Taylor series is provided in this design to compute the cosine function. High precise cosine wave is generated in real-time. Therefore this signal generator is feasible with a wide range of frequency and high stability.This VTs hardware is constructed based on DSP(TMS320C549). The real-time signal generator is implemented in the DSP object board. DSP communicates with personal computer through USB interface, and User can modify frequency and amplification of the output signal in time. VI's software is developed in VC++ and LabVIEW.