Connecting a SMU Signal to a PXI(e) Backplane Trigger Line in LabVIEW

Updated Oct 30, 2023

Environment

Hardware

  • PXIe-4143
  • PXIe-4140
  • PXIe-4142
  • PXIe-4141
  • PXIe-4144
  • PXIe-4145
  • PXIe-4147

Software

  • LabVIEW

Driver

  • NI-DCPower

This article will explain how to route a signal from a PXI(e) SMU card to the backplane trigger lines on a PXI(e) chassis. This process involves using the NI-DCPower VIs to export the SMU signal onto a PXI_TRIG line.

Before proceeding, ensure that a compatible version of NI-DCPower is installed on the development PC. Refer to the NI-DCPower readme document from the NI-DCPower Release Notes for a list of compatible hardware.

In LabVIEW, create a new VI by going to File >> New VI. Follow the steps below to programmatically route a SMU signal to a PXI_TRIG line:
 
  1. Place a niDCPower Initialize With Channels VI on the Block Diagram.
    • This VI and all subsequent niDCPower VIs can be found in the Instrument I/O >> Instr Drivers >> NI-DCPower palette.
  2. Wire a constant/control to the Resource Name and Channels inputs.
    • The Resource Name should specify the name of the PXI(e) SMU card while the Channels input should specify the output channel that will generate the signal.
  3. Next, place a niDCPower Configure Source Mode VI and connect this to the Initialize With Channels VI.
  4. Define the Source Mode as Singe Point if a single channel is going to be used as a source.
  5. Connect a niDCPower Configure Output Function VI to the Configure Source Mode VI.
    • Set the Output Function input to whichever signal type you wish to generate.
    • For the purposes of this example, the Output Function has been set to DC Voltage.
  6. If generating a voltage signal, place a niDCPower Configure Voltage Level VI and specify the Voltage Level for the output signal.
  7. For a voltage signal, connect the niDCPower Configure Voltage Level Range VI. Specify the Voltage Level Range input.
  8. Place a Property Node and wire values for the Active Channel and Source Delay properties.
    • This defines when the device will generate a Source Complete Event.
    • In this example, the Source Delay is set to 0 and the Active Channels should be wired to the Channels constant/control.
  9. Then connect a niDCPower Export Signal With Channels VI.
    • This VI is responsible for routing the signal to the PXI_TRIG line.
    • Select Source Complete Event on the Signal input.
    • Define the desired PXI_TRIG line on the Output Terminal input. For example, to export the signal to PXI_TRIG0, enter "PXI_Trig0" as the Output Terminal.
  10. After this configuration has been set up, the niDCPower Initiate VI can be placed to start the signal generation.
  11. Call the niDCPower Abort With Channels VI to transition the channels from Running to Uncommitted.
    • Older versions of NI-DCPower use the niDCPower Abort VI. This does not allow the user to specify channels and will transition the session from Running to Committed.
    • If using the older VI, the niDCPower Reset VI should be used to reset the device.
  12. Finally, place the niDCPower Close VI  to close the SMU session.


The following code implements all of the steps detailed above:
KB Snippet.png

Note: This image is a LabVIEW snippet, which includes LabVIEW code that you can reuse in your project. To use a snippet, right-click the image, save it to your computer, and drag the file onto your LabVIEW diagram.