Measurement procedure automation and data digitization speeds up measurement performance and data processing. The lack of communication between an instrument and a personal computer requires a person to read the data from the chart of the instrument, which can lead to errors. In addition, people collect data more slowly compared to computers.
In this diploma thesis, the process of building communication between HP4395A instrument and personal computer is described. The spectrum analyzer communicates with a computer via GPIB (General Purpose Interface Bus) communication. The conversion from USB (Universal Serial Bus) to GPIB is handled by GPIB interface developed at the Faculty of Electrical Engineering. Communication between the personal computer and the interface takes place via a USB bus, which is configured as a virtual serial interface (VCP - Virtual Com Port).
The communication logic and user interface are written in the programming language Python. Despite the fact that Python is a slower language, program execution is fast enough, as spectral circuit analysis is a relatively slow measurement.
The library consists of three subprograms that enable the management of the instrument. The first part establishes serial communication between personal computers and instruments. The second part allows GPIB communication. The last subroutine contains the control and monitoring functions of the HP4395A instrument.
The appendix of diploma thesis encloses an example of the use of libraries to build a user interface. The interface allows control of the instrument and displays the measured data in graphical form.
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