Set the Scaling Mode to Scaled in the RIO Mezzanine Card Properties dialog box for the NI 9684 if you want the FPGA I/O Node to return scaled, fixed-point data for the device. If you set the Scaling Mode to Raw, the FPGA I/O Node returns unscaled, binary values for the NI 9684 that you can convert into volts using the following equations. You must convert these values in the host VI Scanned AI

Use the following equation to convert binary values into volts for the scanned AI on the sbRIO-9684.

Volts = Binary Value × 5 V ÷ 4096

Table 660.
where Binary Value is the signed or unsigned value returned by the FPGA I/O Node

Simultaneous AI

Use the following equations to convert binary values into volts for the simultaneous AI on the sbRIO-9684 for both ±10V and ±5V ranges.

Volts = (Binary Value × LSB Weight + Offset)*

Table 661.
where Binary Value is the signed value returned by the FPGA I/O Node
LSB Weight is the value returned by the LSB Weight property
Offset is the value returned by the Offset property

If you do not want to read the LSB Weight and Offset values from the module, you can convert to uncalibrated engineering units by using the following values for Offset and LSB Weight:

Offset = 0

LSB Weight = Typical Input Span ÷ 2ADC Resolution 

Table 662.
where Typical Input Span is 20.832V for ±10V range and 10.416V for ±5V range
ADC Resolution is the ADC resolution value in the hardware documentation for the module

*LSB Weight and Offset are formatted and cannot be used as is. Refer to the Binary to Nominal VI in the LabVIEW\examples\CompactRIO\RMC Specific\NI 9684\NI 9684 High Speed Acquisition\NI 9684 High Speed Acquisition\NI 9684 High Speed Acquisition.lvproj for an example on how to convert the LSB Weight and Offset to the correct format.