Simulated devices in PyVISA: early preview

PyVISA started as wrapper for the NI-VISA library and therefore you need to install National Instruments VISA library in your system. This works most of the time, for most people. But sometimes you need to test PyVISA without the devices or even without VISA.

Starting form version 1.6, PyVISA allows to use different backends. These backends can be dynamically loaded. PyVISA-sim is one of such backends. It implements most of the methods for Message Based communication (Serial/USB/GPIB/Ethernet) in a simulated environment. The behavior of simulated devices can be controlled by a simple configuration in plain text. In the near future, you will be able to load this from file to change it depending on your needs.


To test it you need to install PyVISA 1.6 which is currently only available from GitHub:

$ pip install -U https://github.com/hgrecco/pyvisa/zipball/master

And then install:

$ pip install -U https://github.com/hgrecco/pyvisa-sim/zipball/master
   

For those of you interest in the internals, the plugin mechanism for PyVISA hooks at the VisaLibrary level. Mocking the Library allows for a comprehensive and powerful testing.

By the end of the week I will be blogging about another cool VISA backend which will be opened soon: PyVISA-py. It is a backend that does not require the NI-VISA library. Stay tuned!

Remember that this is an early preview. Submit your bug reports, comments and suggestions in the Issue Tracker. We will address them promptly.

Or fork the code: https://github.com/hgrecco/pyvisa-sim/

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