Obtaining Gain Applied by the Entire System, DAQ, SCXI for a Channel in an SCXI System

This example takes the input limits for a particular SCXI channel and returns the SCXI, Data Acquisition (DAQ), and overall gains being used for this set of input limits, DAQ board, and SCXI module.

Note: The attached zip file contains a VI for LabVIEW 5.1, 6.0, and 6.1.

Background:
The NI-DAQ driver can optimize the system gain in your DAQ/SCXI system to fully utilize the range of your analog-to-digital converter (ADC) for signals from transducers that are naturally smaller than the default range of your ADC. Analog input SCXI modules and the DAQ board can apply gain to your signal. For many modules and DAQ boards, this gain is software-programmable and is configured automatically in the NI-DAQ driver when a DAQ LabVIEW VI is written using the "input limits" input to AI Config.vi.

When you wire in values to the input limits, NI-DAQ calculates the optimal gains for use on the SCXI module and the DAQ card to achieve the appropriate gain. The driver is programmed to increase the SCXI gain to the highest setting possible while staying within your input range, and then it applies additional gain at the DAQ board, if necessary.

To access individual SCXI channels, use the SCXI Channel String: obA!scB!mdC!D

where:
A = DAQ board channel the analog signals are being multiplexed to. In single chassis systems, this is 0.
B = Chassis number, usually 1 in single chassis system
C = Module number within the chassis
D = Channel number for that module

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