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3.3 acquiring data

You will now develop your VI to acquire the data that the ADC is sampling. The VI will acquire 1000 samples ata rate of 100,000 samples per second. Once the 1000 samples have been gathered, the data will be analyzed programmatically todetermine the peak-to-peak amplitude and the DC offset. The data set will be displayed on a graph, and will be written to ameasurement file that can be opened in Excel.

LabVIEW contains a useful set of functions for data acquisition known as DAQmx. DAQmx is NI’s driver configuration software for DAQ devices. We will use the DAQ Assistant function toopen communication with the DAQ hardware, read data from the device, and close communication.

5. On the block diagram, right click to bring up the Functions Palette. (Refer to Figure 4.) The FunctionsPalette contains all of the functions and structures that can be placed directly on the block diagram. Notice that the functions areorganized into sub-palettes by functionality.

Functions Palette

6. Click Measurement I/O>>NI-DAQmx>>DAQ Assist.

7. When you place the DAQ Assistant on the block diagram, a Create New…window will open as shown in Figure 5. This menu will guide you as you configure your software tocommunicate with your hardware.

Create New DAQ Assistant Window

8. Select Analog Input>>Voltage. DAQmx will scan the system for available hardware and present theoptions; as shown in Figure 6.

List of Physical Channels

9. Expand the cDAQ module that is labeled (SCXI-1520).

10. Select ai0, (the analog input channel that the function generator is connected to.)

11. Click Finish.

DAQ Assistant Configuration Window

12. The DAQ Assistant window should now open. Configure the DAQ Assistant as shown in Figure 7.

  • Set the input range from 5 to -5 volts.
  • Change the Terminal Configuration to Differential. (Differential assumes that the voltage is measured between twochannels, rather than referenced to a common ground.)
  • Set the Acquisition Mode to N Samples.
  • Change Samples to Read to 1000 and the Rate to 100,000.

13. When you click OK, LabVIEW will build a subVI according to your specifications.

3.4 amplitude measurement of data

Similar to the measurements made on the oscilloscope, LabVIEW programs can analyze characteristics of asignal.

14. Right click on the Block Diagram to bring up the Functions Palette. (Note that if you click on the FrontPanel you will bring up the Controls Palette, which has entirely different choices.)

15. Select Express>>Signal Analysis>>Tone. The Configure Tone Measurements dialog box will now open. The Tone Express VI will display values related tothe amplitude and frequency of the signal.

Configure Tone Measurements Box

16. Configure the dialog box as shown in Figure 8.

17. Select Amplitude and Frequency in the Single Tone Measurements box.

18. When you click OK, LabVIEW will build a subVI according to your specifications.

19. Place your cursor over the data output terminal on the DAQ Assistant icon. The cursor should change to awire spool. Click on the data terminal and connect the wire to the signals inputterminal on the Tone Measurements icon. This wirerepresents the data flow from the DAQ Assistant to the measurements subVI.

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Introduction to mechanical measurements. OpenStax CNX. Oct 18, 2006 Download for free at http://cnx.org/content/col10385/1.1
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