Changing the Analog Input Configuration For R Series Multifunction RIO Devices

Updated Nov 1, 2023

Environment

Hardware

  • PCI-7831
  • PCI-7833
  • PCIe-7856
  • PCIe-7857
  • PCIe-7858
  • PXI-7831
  • PXI-7833
  • PXI-7851
  • PXI-7852
  • PXI-7853
  • PXI-7854
  • PXIe-7856
  • PXIe-7857
  • PXIe-7858
  • PCIe-7841
  • PCIe-7842
  • PXI-7841
  • PXI-7842

Software

  • LabVIEW FPGA Module

I am using an NI R Series Multifunction RIO device (783xR - 785xR - 7841R - 7842R) with built in analog Input. How can I change the input configuration mode between Differential, RSE, and NRSE?

The steps to change the analog input configuration differ depending on the LabVIEW version you are using. 

LabVIEW 8.2 and Later
  1. Configure a project containing an R-series FPGA board.
  2. Right click on the FPGA target and select RIO Device Setup.
  3. Select the desired configuration from the Analog Input Mode under the Device Settings tab.


Legacy Instructions (LabVIEW 8.0 and Earlier)
In LabVIEW 8.0, follow the steps below to change the analog input configuration for your Multifunction RIO device:
  1. Configure a project containing an R-series FPGA board.
  2. Right click on the FPGA target and select Download Bitfile or Attributes To Flash Memory.
  3. Select the desired configuration from the Analog Input Mode pull-down menu and then click on the Download Attributes button.

In LabVIEW 7.1, you need to use the Embedded Project Manager to configure the board. Follow the steps below to change the analog input configuration for your Multifunction RIO device:
  1. Target LabVIEW to your FPGA board.
  2. Select Tools>>Embedded Project Manager.
  3. Select Tools>>Download VI or Attributes to Flash Memory.
  4. Select the desired configuration from the Analog Input Mode pull-down menu and then download the attributes.
In LabVIEW 7.0, follow the steps below to change the analog input configuration for your Multifunction RIO device:
  1. Target LabVIEW to your FPGA board.
  2. Go to Tools>>FPGA Utilities>>Flash VI or Setup Board.
  3. In the setup window, you can select the desired input mode (differential, non-referenced single-ended, referenced single-ended) by setting the Analog Signal Connection parameter as shown in the attached image. Note that the default values as shown in the window do not necessarily reflect the current state of these attributes on the device.
  4. Click the Flash Attributes button.
Finally, power cycle your computer or your PXI chassis so the FPGA board reads the new attribute values stored in flash memory.

Additional Information

  • The input configuration is external to the FPGA. Recompiling the bitfile is not necessary after changing the input configuration mode.
  • The steps set the input mode for ALL analog input channels. For further details on how to wire the signal connections for the different input modes, please refer to the User Manual linked below. 
  • For more information about the differences and trade-offs between analog input configuration modes (Differential, RSE, and NRSE), please refer to Field Wiring and Noise Considerations for Analog Signals