- Why Python in Test Instruments
? Python combines three critical advantages for instrumentation:
• Access to devices via open standards (VISA, SCPI).
• Extensive ecosystem of libraries (NumPy, Pandas, Matplotlib), ideal for signal analysis.
• Integration with automation and repetitive testing, reducing engineering time.
Unlike traditional environments such as LabVIEW or proprietary languages, Python offers portability, reduced cost, and code traceability for complex test benches.
2. Controlling Oscilloscopes with Python and PyVISA
Most modern oscilloscopes from manufacturers like Keysight or Teledyne LeCroy support SCPI (Standard Commands for Programmable Instruments) commands. These commands are sent through standard interfaces (USB, Ethernet, GPIB) using libraries like PyVISA, which acts as a bridge between Python and the instrument.
Examples and Available Resources
• The keyoscacquire library is an open-source project for capturing traces from Keysight InfiniiVision oscilloscopes using PyVISA. It allows exporting waveforms to CSV or NumPy arrays for further analysis and accelerates data transfer compared to ASCII format.
• The oscope-scpi package offers a generic approach to controlling Keysight MSO-X/DSO-X oscilloscopes and other SCPI-compatible series from Python.
• For Teledyne LeCroy instruments, projects like TeledyneLeCroyPy encapsulate functions for connecting to the instrument, waiting for triggers, and retrieving channel data in formats ready for analysis with scientific libraries such as Pandas and Plotly.
These libraries demonstrate how Python can interact directly with the instrument: from sending a start instruction to programmatically downloading, reconstructing, and visualizing complete signals.
3. Advanced Automation
One of the greatest benefits of Python is the ability to integrate oscilloscopes into automated test routines:
• Run measurement sequences at scheduled times.
• Automatically generate reports and graphs.
• Integrate oscilloscope acquisition with other test instruments (signal generators, spectrum analyzers, etc.).
Furthermore, manufacturers like Keysight offer programming resources that compile examples of remote control of test instruments—including oscilloscopes—in languages such as Python, MATLAB, or LabVIEW.
4. Analyzing Acquired Data with Python
Capturing waveforms from the instrument is only the first step; Python allows for advanced processing:
• Resampling and filtering with NumPy and SciPy.
• Statistical analysis of hundreds of traces.
• Interactive visualization with libraries such as Matplotlib or Plotly.
• Machine learning to detect patterns in signals.
The advantage of having the data in formats such as NumPy or CSV facilitates its direct integration into reproducible and documentable analysis pipelines.
Additionally, manufacturers like Rohde & Schwarz include methods in their documentation for accessing waveform data from Python after acquisition, allowing for data processing beyond the instrument's native capabilities.
5. Best Practices and Recommendations
To get the most out of using Python with oscilloscopes:
• Use PyVISA as the basis for SCPI communication.
• Prefer binary data transfer over ASCII to accelerate capture.
• Create control abstraction to reuse code across different oscilloscope models.
• Document and version scripts to facilitate maintenance and reproducibility.
At the infrastructure level, Python also allows you to build custom graphical interfaces or integrate web dashboards for real-time monitoring of automated tests.
Conclusion:
Using Python to control, automate, and analyze oscilloscope data is moving from an alternative approach to a best practice in labs and production environments. Thanks to existing libraries and support from standards like SCPI and VISA, engineers and developers can create flexible solutions that integrate measurement instrumentation with modern data analytics and advanced automation.
While tools and resources vary depending on the oscilloscope manufacturer and model, Python's potential to simplify and scale test systems is clear and increasingly adopted in the industry.
Adler Instruments and LeCroy present their LabMaster 9 Zi-A modular oscilloscope system
LeCroy Corporation's new LabMaster 9 Zi-A line of modular oscilloscopes delivers more bandwidth (45 GHz), sampling rate (120 GS/s), and channels (up to 20) than any other oscilloscope, with an analysis memory of up to 768 Mpts/ch. Furthermore, the LeCroy LabMaster 9 Zi-A...
