PXIe-5840 with PXIe-5653: RFmx locks the reference clock to the clock sourced at the PXIe-5840 REF IN terminal that is previously configured by an NI-RFSG session. Connect the NI-5840 REF OUT connector to the PXIe-5653 REF IN connector.
Configure open NI-RFSG sessions to the device to use ReferenceIn for the PXIe-5840 or OnboardClock for the PXIe-5840 with PXIe-5653.
PXIe-5663/5663E/5665/5668, PXIe-5644/5645/5646, and PXIe-5820/5830/5831/5831 with PXIe-5653/5832/5832 with PXIe-5653/5840/5841/5842/5860: This configuration does not apply.

Syntax

Namespace: NationalInstruments.RFmx.InstrMX

public const string ReferenceIn2