Selecting an Input Voltage Range on Multifunction Reconfigurable I/O Devices

Updated May 31, 2023



  • USB-7855
  • PXIe-7846
  • PCIe-7846
  • USB-7846
  • USB-7856
  • PCIe-7856
  • PXIe-7856
  • PCIe-7857
  • PXIe-7857
  • PXIe-7858
  • PCIe-7858
  • USB-7845
  • PXIe-7847
  • PXIe-7861
  • PXIe-7862
  • PXIe-7867
  • PXIe-7868


  • LabVIEW


  • NI R Series Multifunction RIO

According to its datasheet, my FPGA device supports several different input ranges, e.g. ±2 V and ±10 V. How can I select a different than the default range?

There are two ways to switch between the different input ranges your Multifunction Reconfigurable I/O Device supports:

Using LabVIEW Project Explorer
Follow these steps to change your device's input voltage range:
  1. Right-click the device on Project Explorer.
  2. Click Change I/O Configuration.

  1. A dialog box named "Configure R Series I/O" pops up. Select your preferred Voltage Range. Note: The input range is a per-channel setting, you can pick a range per channel.

  1. Recompile your FPGA code.

Programmatic Approach
The FPGA I/O Property Node allows read and write access to the Voltage Range property of each I/O channel. Please note that this property overwrites the value configured in Project Explorer's Configure R Series I/O dialog using the steps described above.

Additional Information

All accessible properties of an I/O module are explained in its reference, e.g. NI USB-7855R OEM Reference for the USB-7855.