PyVISA 1.6 brings comprehensive resources classes, thread-safety and more

PyVISA is a Python frontend for the VISA library that enables controlling all kinds of measurement equipment through GPIB, RS232, USB, Ethernet among others interfaces.

PyVISA 1.6 release is close and it brings several new nice things. One of the most visible improvements is the addition of a comprehensive set of resources classes, each mapping to a one of the 13 types of resources. Each class implements the methods and attributes that the specific session can handle, providing a Pythonic way to interact with the device (See here). This has allowed us to implement higher level functions such as the group execute trigger in the GPIB Interface.

PyVISA 1.6 brings a much better way to query a device for values, providing a comprehensive API to convert back and from ASCII and binary blocks. An API to write values to a device has been added (See here).

PyVISA 1.6 is thread-safe. While the VISA library has always been thread-safe, PyVISA was not. We have refactored the code removing several global variables that were used to handle state and tweaked the API accordingly.

PyVISA 1.6 continues on the road started with 1.5 to improve debugging, usability and reporting. The quality and density of logging messages have been improved as well as the information provided with the error messages. Python 3.4 Enums are now used to handle constants (the backported packaged enum34 is installed in older Python version).

There is one more change under the hood. PyVISA 1.6 can discover and use other backends to talk to devices (See here). This feature is allowing us to prototype some new packages about which I am going to blog next week.

All these things are only possible as we have dropped some backwards compatibility requirements. In particular, we have removed the legacy package, the string manipulation functions and all the singletons. Most programs will run without major changes but in any case, all API modifications are documented here to help with the transition.

All this would not have been possible without the support of a great community that has been helping with the development and testing different development versions. But we really need your help before uploading this to PyPI as an stable release. PyVISA is all about interacting with your operating system (finding and locating the C library) and you instruments. With the variety of platforms around, it is very difficult to test. We are asking all users to install PyVISA from the github repository and test it on your programs. You can install PyVISA or upgrade to the development version using pip:
 
 
$ pip install -U https://github.com/hgrecco/pyvisa/zipball/master

Again, this release is only possible thanks to the contribution of a lot of people that contributed bug reports, testing and code. Thanks to everybody!

Submit your bug reports, comments and suggestions in the Issue Tracker. We will address them promptly.

Read the development docs: https://pyvisa.readthedocs.org/en/master/
or fork the code: https:/https://github.com/hgrecco/pyvisa/

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