Acquisition tension bufferisé

bonjour,
J'utilise labview 10.0 et une carte NUI CB 68LP et j'aimerai lire des voies analogiques sur ma face avant tout en fesant une acquisition de tension bufferisé de ces voies.
je ne sait pas si je suis clair voici en gros ce que je voudrai faire.
dite moi si cela est possible et comment je doit raccorder cela pour que sa fonctionne.
merci d'avance
Attachments:
prog mesure de tension bufferisé.vi ‏32 KB

Bonjour Tigrounours,
Vous avez la possibilité en effet de créer une tâche d'acquisition de
données (Tension, courant, déformation...) de façon continue et finie entre
autres. Les données issues de la lecture du Buffer (la fonction DAQmx Read),
vous permettent de visualiser sous forme de tableau et/ou de graph les données
issues de votre acquisition.
A cet effet, LabVIEW vous offre la possibilité de charger directement des
exemples prêts à l'emploi qui utilisent l'API DAQmx pour réaliser ce type de configuration. Pour cela, je
vous encourage à ouvrir LabVIEW, et depuis la fenêtre de démarrage sélectionner
"Recherche d'exemples" -> E/S matérielles->DAQmx -> Mesures
analogiques. Ensuite, vous pouvez naviguer dans le répertoire et prendre en
main les différents exemples, afin de sélectionner celui qui correspond à votre
applicatif, et votre périphérique d'acquisition de données.
De plus je vous encourage à prendre connaissance des informations présentes
depuis notre site internet sur l'utilisation du driver NI-DAQmx qui permet
d'assurer le dialogue avec les périphériques d'acquisitions de données de
National Instrument:
Learn 10 Functions in NI-DAQmx and Handle 80 Percent of Your Data
Acquisition Applications
http://zone.ni.com/devzone/cda/tut/p/id/2835
Getting Started with NI-DAQmx: Main Page
http://zone.ni.com/devzone/cda/tut/p/id/5434
La carte NI CB 68LP, est un boîtier de connexion entre vos capteurs, ou
signal à mesurer et la carte d'acquisition à proprement parlé, qui est
connectée à votre ordinateur ou châssis PXI.
Cordialement,
Rémi D.
National Instruments France
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Help with DAQmx tension measurement and saving to spreadsheet file with NI USB-6218 (very urgent !)

Hello people,
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I'll add both VIs as attachment so it can help you help me, thank you.
Basically what I need is to acquire 15 tensions with a given number of samples per channel (the same for each channel) and then plot it in matlab.
Note the first VI has switches to "unblock" each channel but it doesn't seem to be working, please look at both VIs.
It's very urgent, I could fail my school year if I fail this project.
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Attachments:
Projet EM acquisition - Copie.zip ‏78 KB
projet autre version envoyer sur forum.zip ‏20 KB

Hi Thank you very much for your help, in the meantime, I've changed the project to (see attachment), now
it is at least writing the waveforms to the txt file, but again there is an another problem, it seems to be ignoring the
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What is missing ? Also I'd like to have a clock for my samples, that is when I plot in matlab I do not just plot random numbers, but the
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Attachments:
acquisition 5 voies.zip ‏61 KB

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Use PFI pin to trig ??

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Hi
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Attachments:
Graph.jpg ‏55 KB

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How to do multi-buffered acquisition on NI-6115

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Greetings,
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In addition to LabVIEW itself you will find our web site's Developer Zone extremely useful.
Development Library
http://zone.ni.com/devzone/devzone.nsf/6ae7945502d89dea0625685500506e1f/4d58b1b80ec41ef70625683f006e1d6d?OpenDocument
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Role of timing and rate in the buffered acquisition

Hi
I am trying a buffered acquisition.
In the timing VI, when i specify the rate to be around 2000, i do not get any error message and the data acqusition continues. Also i am giving a time of 1000ms in the wait until next millisecond vi in the while loop.
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-200279 DAQmx Read (Analog 1D DBL 1Chan NSamp).vi:1<append>
Property: RelativeTo
Corresponding Value: Current Read Position
Property: Offset
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Somil Gautam
Think Weird
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Go to Solution.

Thanks.
Actually, setting the timing in while loop to 1/10 th rate in the timing VI is a good practice.I had increased the timing and as a result the buffer was getting overwritten.
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Double buffered acquisition with PCI-6031E

For a meagre 1 channel acquisition at a sample rate of 100 Hz and buffer size of 1000, I get this message:
"Warning -10026 occurred at an unidentified location.
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Can someone explain the reason

My favorite way to get this error is to accidentally wire something to the "number of buffers" input on the AI Config VI. This should be left unwired most of the time. You can also get this error if the buffer size is invalid. This would be less than 3 or greater than 2^24 for your board. See KB 1JAKLN6Q for more information.
Finally, as a check I would run one of the shipping example programs to see if you don't get the same problem. Then you can compare your program to it. Try "Acquire N Scans.vi"
Hope this helps!
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National Instruments
http://www.ni.com/support

Real-time PID control and continuous buffered acquisition. Does it work together?

I use the "real-time PID control.vi" that acquires single AI point and generate single AO point in every "while loop" iteration to control a piezo actuator motion. Simultaneously I need to do (in another loop) a continuous buffered acquisition of another two AI channels (in the same rate as first AI channel).
It does not work together.
Does anybody know how to fix it?
Platform: LabVIEW 6.1
Board: PCI-6024E

Hi,
I would try to avoid the idea of using a separate loop since the PID
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Regards,
Dave R.
varmih wrote:
> I use the "real-time PID control.vi" that acquires single AI point and
> generate single AO point in every "while loop" iteration to control a
> piezo actuator motion. Simultaneously I need to do (in another loop) a
> continuous buffered acquisition of another two AI channels (in the
> same rate as first AI channel).
> It does not work together.
> Does anybody know how to fix it?
>
> Platform: LabVIEW 6.1
> Board: PCI-6024E

Acquisition de tension et fréquence sur ni6010

Bonjour
Je souhaite faire des acquisition de tension de de fréquence (tous cela en continue) avec une carte ni6010
gamme de tension 0-5V
fréquence x-500Hz
j'ai essayé se montage mais sa ne marche pas (pièce jointe)
pourquoi??
Pièces jointes :
acqui.JPG ‏70 KB

Qu'est-ce qui ne marche pas? C'est un peu vague comme description pour pouvoir t'aider!
Olivier L. | Certified LabVIEW Developer

Buffered ring acquisition with IMAQ 1394 2.0 (beta)

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Flexmotion single point acquisition with Analog buffered acquisition

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I checked and the Read Position VI loop runs properly while the motion profile is running (without any analog acquisition through my 6023E card).
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Attachments:
simultaneous_DAQ_on_6023E_and_reading_7344_flexmotion_(simple_example).vi ‏149 KB

Multi-buffered acquisition with digital trigger

I have a PCI-MIO-16E1 and I need to do three channel (250KHz/channel - ~400 scans/trigger) multi-buffered acquisition with digital trigger (trigger => 30 Hz).
I could not find any example of multi-buffered acquisition. Could anybody help me?

Hello,
I assume that you are refering to a retriggering setup where each time you recieve a trigger you take 400 samples on each channel at a rate of 250kHz per channel (total scan rate = 3CH * 250kHz = 750kHz).
In order to keep the system hardware timed you can use the two counters on the board to produce a retriggerable pulse train that will act as your scan clock. For example each time the counter recieves a trigger it will output a clock signal of 750kHZ with 400 or so pulses in order to take ~400 scans/trigger.
This clock signal can then act as the scan clock for your 3 channel analog input operation.
Now we have to figure out how to set up the retriggerable pulse train from the counters and have the analog input use the counter output as a sca
n clock.
Good thing there is an example that is already written
http://zone.ni.com/devzone/explprog.nsf/6c163603265406328625682a006ed37d/aab61e455564a04d862568930018e725?OpenDocument.
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Acquisition tension bufferisé

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