Unable to Find the Option to Change Polarity of Digital Edge Trigger in NI DCPower Python API

Updated Jun 24, 2020

Reported In

Driver

  • NI-DCPower

Programming Language

  • Python

Issue Details

I am using the NI DCPower Python API to control my NI SMU device. I want to set the digital measure trigger to be Falling Edge but I cannot find a property or method to do so in the documentation. Is the digital trigger edge type configurable?

Solution

The NI Modular Instruments Python API is an Open-Source project available in the GitHub repository, nimi-python.
The ability to select the digital edge trigger is not exposed in the NI-DCPower Python API. The edge type is Rising by default. 
This property is not exposed because there is no obvious use case for it and to keep the API leaner.

If there is a critical need for it, the additional functionality can easily be added in the Python and built locally.

Additional Information

  • The 0.8.0 version of the Python API included a property that allowed the configuration of Rising/Falling edge but it was removed in the 1.0.0 version of the API. Refer to the GitHub issue #902 for more details. 
  • The nimi-python API calls the DCPower driver through its' public C API using the ctypes library, so it is essentially a wrapper for the NI DCPower C API.
  • Use the GitHub repository or contact NI Support to provide feedback or receive support.