1 sample per 1 ms

I am using a DAQcard 1200 and i need to acquire data using hardware timing controlled by the LAbview software to acquire 1 sample per 1 ms
grays

Grays,
There are multiple ways to sample at 1 kHz with the DAQCard-1200. If you are only scanning on one cahnnel, you can actually achieve up to 100 kHz (100 samples per 1 ms). The best way to begin this program is to look at the DAQ examples that ship with LabVIEW. The deciding factor in how you wish to set up this acquistion will be the conditions for starting/stopping the acquisition. If you want to trigger off a digital signal, explore the "Hardware Triggering" examples. If you want to acquire a specific number of data points and then stop, use one of the "Acquire N Scans" examples. Otherwise, you may acquire data continuously with a "Continuous Acquisition" example.
For more information on connecting your signals and specifics concerning your boa
rd, check out the online manual here
Good Luck,
Eric
Applications Engineer
National Instruments

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Acquire, display, and write data at 50 samples per second

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Galen,
Looking at your vi, I would recommend writing to your file in a different way. The function you are using is actually opening, writing, and then closing the file every time you call it. This greatly increases the amount of resources being used. Take a look at the Cont Acq to Spreadsheet File.vi example and note that the file is only being opened and closed once. The data is being written to the file during execution of the program, and then closed when the app is done running. The example is done in traditional DAQ but you should be able to do something similar with DAQmx. Try this and let me know if it helps.
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How to Extract the Freq List, Cycles per Freq and Samples per Cycles of sweep waveform

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Look inside the palette called Signal Processing - Waveform measurements. There are a lot of functions here that you can use to get the information you desire. For instance, the Extract Tones function will output an array of clusters, with each cluster element giving the frequency, amplitude, and phase of the signal component. Go through the entire arry to see each frequency component of the complex waveform.
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Attachments:
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Sample clock vs sample per channel per second

Referring to this link http://digital.ni.com/public.nsf/3efedde4322fef19862567740067f3cc/dbe7ac32661bcf9b86256ac000682154?OpenDocument
What's the difference between sample clock and sample per channel per second? Looks the same to me.

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Set variable samples per chanel from counter

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Hi, GerdW. Thanks for reply. I want Sample Rate and Samples per Chanel to come from couter. CI is a metal plate with 52 tooth. The speed of metal plate is 500 cycles/min but it is not constant ( may be 490-520). For example rate of cycles is 500/60=8.33 cycles/sec. Rate of edges (tooth) is 8.33*52=433 edges/sec, but when speed goes over or under 500 the rate is different. How to put that variable samples in sample clock on AI?
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How to use ni-6008 and build a four channel data acquisition at a rate of 250 samples per channel and display all the data in a waveform chart

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Hi kdm,
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Buffer size and samples per channel

I have a question regarding the allocation of the output buffer. I have
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I can post the whole thing but I'll talk a little about it. It's a producer consumer loop with a continuous analog input sample from external clock program in the producer loop. Right now the consumer loop has a simple write to spreadsheet VI in it but eventually I want to average each revolution (well, two since it's a four stroke but that's neither here nor there) of pressure traces and spit out a single curve.
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Can you set samples per trigger for sound vi?

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Hello,
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Sample per channel and sample to read

Hello everybody
I am new in LABVIEW and I have some difficulties with something.
I don t know exactly what is the difference between the sample per channel et the sample to read. I believe knowing that the sample per channel is the size of the buffer which is more big than the sample rate but I don t know what is the sample to read.
I ve tested with different sample per channel and sample to read. Sometimes I have an error and sometimes know and I would like to know why. If you have any example for I understand better, it will be great.
I really need to understand this part for my project
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Romaric GIBERT
Solved!
Go to Solution.

Hi Roro,
As you mentioned, when acquiring continuous samples you can specify the sample buffer size by placing a value at the input "samples per channel" on the timing vi. The "number of samples per channel" input on the read vi which automatically names a control/constant with "samples to read" specifies the number of samples you wish to pull out of the buffer in one go when reading multiple (N) samples. This link may provide a bit more clarification. I have also attached a good example from the NI example finder which you may find useful to explore. I'm assuming you are using the DAQmx driver set so please let me know if this is not the case, but the same principles should apply either way.
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Did you check the help file for the DAQmx sample clock function?
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Error -201402; how do you programmatically determine 'Samples per file' size

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Thank you for your help.
The Get Volume Info does indeed give me the Sector Size, however i still had problems with working out what multiple of the sector size to use.
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Regards,
Helen
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Export Ultra Beat Kit to use on another computer? Multiple samples per key?

I know I can save it in a session, but I'd like to export a custom UB kit, along with its samples, as a single file/folder for use on another computer. Is this possible?
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To answer the second question, it is certainly possible. Not that I have done it intentionally but on more than one occasion I have imported multiple samples into exs only to find that every sample plays when I press one key...
Check the mapping!
/j

Can 10000 sample per second can be acuire from a sensor through cRIO

I just want to know, can I acure 10000 smaple (when the programme run in real time) per second per chanel or more, when data taking from a sensor, through the cRIO.

Bikash wrote:
Can I apply this method in simulation loop. Where I want make my control algorithm.
It sounds like a perfect application for your needs. Remember to buy powerful hardware not having to worry about the performance.
http://sine.ni.com/nips/cds/view/p/lang/en/nid/210400
Or something similar performance with a PXI solution.
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Fehler nach "Samples per Channel"

Hallo,
Ich verwende das cRIO System NI 9074 mit AD-Wandlermodul NI9239. Hier sollen Daten kontinuierlich gewandelt und anschließend gespeichert werden. Allerdings gehen hierbei immer nach einer Sampleanzahl von „Samples pro Channel“ Daten verloren. Dies wird auch im in LabVIEW angezeigten Graphen sichtbar. Bei einem Sinussignal am Eingang ist dann ein Sprung erkennbar.
Der Speicher des FIFOs ist großgenug, zumindest wird mit kein Überlauf angezeigt. Kann mir irgendjemand weiterhelfen?
jukr
P.S. Ich verwende LabVIEW 2010
Attachments:
FPGA.vi ‏77 KB
PC.vi ‏365 KB

Hi Jukr,
it is useful to write forum posts in english; you will get many more replies :-)
I don't expect the error to be caused by the measurement. Maybe there are some parts in the network streaming that are not stable enough?
Just have a look at the following example and compare it to your network connections. You might find it useful!
Reference Example for Streaming Data from FPGA to cRIO to Windows
If the example won't help you finding the error, please attach your project.
Have a nice day,
Stefan Egeler
NI Germany

1 sample per 1 ms

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