1 rating:

1 out of 5

Rate this Document

Using the LVDS Output of Arbitrary Waveform Generator

Hardware: Signal Sources (AWG/FG/AO)>>Arbitrary Waveform and Function Generators>>PXI-5421, Signal Sources (AWG/FG/AO)>>Arbitrary Waveform and Function Generators>>PCI-5422, Signal Sources (AWG/FG/AO)>>Arbitrary Waveform and Function Generators>>PCI-5422, Signal Sources (AWG/FG/AO)>>Arbitrary Waveform and Function Generators>>PCI-5421, Signal Sources (AWG/FG/AO)>>Arbitrary Waveform and Function Generators>>PXI-5422, Signal Sources (AWG/FG/AO)>>Arbitrary Waveform and Function Generators>>PXI-5441

Problem:
How do I use the LVDS Output of my Arbitrary Waveform Generator?

Solution:
Several arbitrary waveform generators, including the PXI-5421, PXI-5422, and PXI-5441, are able to generate digital patterns with the LVDS digital output connector. The digital pattern generation is a digital representation of the waveforms generated on the analog connector of the device at the same rates as the analog signal. The arbitrary waveform generator is able to generate analog values through a 16-bit digital-to-analog converter. However, the bit-wise representation of these 16-bit signed integers can also be generated as digital values at the LVDS output of the arbitrary waveform generator.

For example, the numeric value ‘78’ can be represented by the 16-bit array: [0,0,0,0,0,0,0,0,0,1,0,0,1,1,1,0]. When this value is generated with a gain of ‘1’ and an offset of ‘0,’ the actual analog voltage is: 2.38 mV. The translation between a signed 16-bit integer and the actual analog value is represented by the following equation:

Analog Value = ((Range * I16 Integer) / 2^(16 bits)) + Offset

Thus, generating 2.38 mV at the analog connector results in the generation of the digital array, [0,0,0,0,0,0,0,0,0,1,0,0,1,1,1,0], across the 16 pins of the digital LVDS connector. Note that digital pattern generation is not enabled by default, but must be enabled programmatically.

To enable digital output, the function: “niFgen Configure Digital Patterning” must be called in LabVIEW (shown below):

In C, digital output can be enabled by calling the function: “niFgen_EnableDigitalPatterning.”

Related Links:
NI-FGEN Support: NI Signal Generators Help

Attachments:

Report Date: 03/21/2006
Last Updated: 04/16/2007
Document ID: 3VKA3E2W

Your Feedback!	Poor  |  Excellent							Yes	No
Document Quality?							Answered Your Question?
	1	2	3	4	5
Document needs work? Please tell us why.
Please Contact NI for all product and support inquiries.