4. VISA in Programming Languages

There are many programming languages offering the possibility to remotely control Test & Measurement instruments.

In this guide, we focus on:

• Python in PyCharm
• MATLAB®
• C# in Visual Studio
• LabVIEW™
• ANSI-C in LabWindows/CVI™

In the following sub-chapters, we discuss advantages and disadvantages of each language. Included ready-to-use example for each of these languages should help you getting started. The screenshots emphasize simple code change in case you change physical connection to your instrument. They also show used layers between the application and VISA.

An installation of VISA is a precondition for all the examples below.

Python in PyCharm

Advantages: Intelligent code editor, safe refactoring, allows for tracking code changes, excellent debugger, also available for Linux.

Compared to pure PyVisa, RsInstrument provides many extended features - proper session attribute settings, synchronization functions, error checking, large data transfer in both directions.

Disadvantages: Missing compiler means you code is only tested for errors during execution.

In Python 3.x, you use RsInstrument module that internally uses PyVISA. You change the resource string in the RsInstrument class constructor.

Pycharm Instrument Control Plugin

Check out our new Remote-Control plugin for Pycharm - it helps you writing your remote-control scripts.

You find the documentation here.

C# in Visual Studio

Advantages: State-of-the-art programming environment, optimized for high performance.

Disadvantages: Requires advanced programming knowledg.

In Visual Studio C# or VB.NET, you use the RsInstrument modul (assembly), which provides same features as the RsInstrument module for Python - proper session attribute settings, synchronization functions, error checking, large data transfer in both directions. You only have to change the resource string in the RsInstrument constructor. The example link below also contains a Visual Basic .NET project.

LabVIEW

Advantages: Ideal for engineers without the need for advanced programming skills, specially developed for instrument remote control applications.

Disadvantages: Lower performance by graphical tasks, difficult to compare versions due to graphical source code.

In LabVIEW, you change the instrument resource string for the LabVIEW function VISA Open. The session stays valid even if your program stops. If you are using instrument drivers, refer to the dedicated application note 1MA228