Pci-6289 delay

Hi guys
I am facing a problem with simultaneous clocking and triggering capabilities of the PCI-6289 Multifunction Daq card. To facilitate easier understanding the application i am working on is bench characterization of adc using the PCI-6289 , I use the 16 bit D/A onboard the card to generate the input signal to the adc , each time a conversion happens the adc puts out a pulse signal , I use the pulse signal as an clock for the data acquistion to happen exactly each time an conversion is done.
The thing is I want the signal generation and data acquistion to be synchronized perfectly , have tried a couple of variations of programs in Labview .I have attached two versions of the programs , one uses the more basic data acquistion functions to generate the signal and try to acquire it at the same time after averaging out some samples , the other version tries to use the daq assistant to try and synchronize the data acquistion with the generation .
In each version there appears a small delay which translates to code offset in the very begginning , The daq assistant grays out the triggering area which i suppose could be used for making sure the data acquistion only happens when the signal is present and only when the conversion pulse is high.
If anybody could suggest a way for the clocking and triggering using either daq assitant or the more basic vi's ,it would be great.
Also if it could be clarified if this is a limitation of the card would appreciate it.
thank you
Chiplearner
Attachments:
datavalid_validl12.llb ‏1848 KB
lv gen.vi ‏474 KB

What you need to do is perform Multi function Synchronization
Read this link to understand Multi function synchronization
Also search in Examples shipped with LabVIEW to find Multi function synchronization example VI's
Find examples>>Hardware input output>>DAQmx>>Synchronization>>Multi function folder
Message Edited by devchander on 08-23-2006 03:27 AM

Similar Messages

What's the dynamic range of PCI-6289?

Dear Sir:
Could you tell me the dynamic range of PCI-6289?
Is there any difference using PCI-4472 or PCI-6289 when measuring vibration signal?
Thank you!
Regards,

Hello,
The PCI-4472 would be best suited for vibration measurments. It has 24-bit resolution, Simultaneous Sampling, Hardware Time-to-Frequency Domain Conversion, 110 dB Dynamic Range, and hardware filtering. See the following Link for more details on the 4472: http://sine.ni.com/apps/we/nioc.vp?cid=10572〈=US
The 6289 was not built with vibration analysis in mind, the the dynamic range is not spec'd.
Let me know if you have any further questions.
Sean C.

High Noise on Analog Output PCI 6289

Hi guys
I am using a PCI 6289 M series device for A/D characterization , I am using the device both for the analog output generation and also for data acquistion of the digital lines , The dynamic tests for the A/D were showing a very poor SNR ratio of the ADC, it is a 12 bit adc so technically in the ideal case i should atleast see 90 db but the resulting figure was way lower around 40 db .
I connected the A0 from the PCI 6289 brought out to a scb-68 block to a RHODE and SCHWARZ spectrum analyzer , the above spectrum analyzer is a decent one with good analysis capability and I was surprised to see a SNR of 50 db , the data sheet says that PCI 628X devices have a internal 16 bit DAC so technically the SNR should be atleast 90 db even if 6 db were removed for the harsh environment of the computer .
please advise , have anybody else faced this problem , the data sheet does not give a figure for the SNR ratio of the card , since i need to test a 12 bit adc , thought that 6289 would be up to the task since it has a 16 bit DAC.I am using the Noise shielding cables and also SCB-68 block , the block is far removed from other power supplies .
any ideas why the noise is occuring , one of my colleagues says maybe the harsh environment inside the pc enclosure causes it , is it necessary to use a separate PCI box for the card and then connect the card to the computer , is this standard procedure ?????.
and also does the PCI -6289 have a filtering option for the analog output , all i could find was the filtering for input.

Hi Tom
Thanks a lot for responding to the thread , did not expect a response in the holiday season . The SNR for the 12 bit one was a typo , was referring to the 16 bit onboard dac in the M series card , which technically should ensure a clean input signal having atleast 90 db .
The info you have given helps a lot , i suspect the conditions inside the pc might be causing it , also i am driving the analog output from the card at almost its limits of 2.5 MS/s , the sample rate specification for the card on the data sheet says 2.8 MS/s , also i notice the settling time requirement for the outputs is 3 us which i suspect will put the onboard DAC under quite a load.
If the conditions inside the PC cannot be rectified , where can i find a external PCI box which can be connected to the computer or does such a box exist only for the PXI cards ? will that necessarily rectify the problem and also since filtering is not possible on the card itself , I remember reading the scb -68 connector block has single RC output filter option , i would have to use discrete R,C components to make it but notice on the right hand corner some pcb holes are provided , would this help.
Would appreciate your Response
Thank you
Chip learner

Analog out DMA performance problems

I'm working on an open-source driver for m-series and e-series boards (http://www.comedi.org). I've discoved some performance problems doing dma to analog outputs that I can't resolve. In summary, dma transfers to the analog output of a PXI-6281 in a pxi crate being controlled through a mxi-4 connection (pxi-pci8336) are VERY slow. I'm talking 250k samples/sec slow. That's the maximum speed the dma controller can fill the board's analog output fifo from host memory. I've also got an older PXI-6713 in the same crate, and dma transfers to it are about 15 times faster (about 3.5M samples/sec). I did notice that clearing the dma burst enable bit in the mite chips channel control register caused the 6713 to slow way down to something comparable to the 6281 (about 500k samples/sec). Setting or clearing the burst enable bit had no effect on the speed of the 6289. Is there some special mojo that needs to be done to enable burst transfers on the 6289? Also, even the relatively speedy 6713 does dma transfers much slower than it should, since the pxi-pci8336 advertises 80MB/sec sustained transfer rates over mxi4. Can you provide any insight into this matter? I've already looked through the ddk, and a register level document describing the mite chip, and example code which had chipobjects for the mite and an analog input example.
By the way, dma transfers for analog input on the 6281 weren't as bad, I didn't measure the transfer time, but I was at least able to do input at 500k samples/sec without fifo overruns.
I'll post more detailed performance measurements in a subsequent post, and include measurements for a couple other similar pci boards (a pci-6289 and pci-6711). In case you're wondering, neither of the pci boards get anywhere close to the bandwidth provided by the pci bus, but they're not as spectacularly bad as the pxi-6281.

Here are my measurements:
PCI-6711, tested on 1.4GHz Pentium 4:
5.2 to 5.3 milliseconds to load fifo to half-full using dma. 0.9 to 1.0 microseconds to write to a 16-bit register. 1.9 to 2.1 microseconds to read from a 16-bit register. The mite's burst enable bit has no effect.
PXI-6713, tested on 3.2GHz Pentium D:
2.2 to 2.4 milliseconds to load fifo to half-full using dma. 0.5 to 0.7 microseconds to write to a 16-bit register. 5 to 7 microseconds to read from a 16-bit register. Turning off the mite's burst enable bit causes the dma fifo load time to increase to 16 to 17 milliseconds.
PCI-6289, tested on 3GHz Pentium 4:
2.0 to 2.2 milliseconds to load fifo to half-full using dma. 0.4 to 0.6 microseconds to write to a 16-bit register. About 1.2 microseconds to read from a 16-bit register. The mite's burst enable bit has no effect. I could do streaming analog output on 1 channel with an update rate of about 2.1MHz before the board's fifo started to underrun.
PXI-6281, tested on 3.2GHz Pentium D:
18 to 19 milliseconds to load fifo to half-full using dma. 0.3 to 0.4 microseconds to write to a 16-bit register. 4 to 6 microseconds to read from a 16-bit register. The mite's burst enable bit has no effect. I could do streaming analog output on 1 channel with an update rate of about 250kHz before the board's fifo started to underrun.
Notes: the 671x boards have a 16k sample ao fifo, the 628x boards have 8k.
The 4 to 7 microseconds times to read a register on the PXI boards seems large too, is that normal overhead for going over the mxi-4 connection?
I wasn't doing anything else intensive on the pci bus during these tests. For what it's worth, according to pci specs the two pci boards should be able to dma their analog output fifos to half full in less than 150 microseconds.

PID control of Counters (PWM)

Hello everybody!!
I work on a closed loop PID controlled problem (Labview 8.5) and I have a couple of questions in order to make some progress!
Firstly, I have to declare that my loop is composed of 2 AI channels (2 accelerometers), 1 AO channel (excitation channel-shaker), and 2 CO (for pulse creation PWM-controllers). The idea is very simple. When the AI (channel 1) value surpass or underpass a predetermined threshold value, then the appropriate CO should be activated in order to apply the necessary control forces and simultaneously to copy my data values of both AI channels in binary style for CPU velocity reasons! BUT, with the PID controller I want to optimize the Duty Cycle value of the pulses!
My questions are :
1) Why when I put Kp=Ti=Td=0 ( = run WITHOUT control) I can copy ALL the AI samples and when I start to activate the PID controller (let’s say for only Kp=0.5) I CAN’T copy ALL the AI samples? Where is my fault?
2) About the PID vi which I use, is it correct or I should use the PID vi for ARRAYS?
3) And finally, about the Boolean statement just before the Case Structures and the Shift Register, is it ok/necessary?
I attach two vis, the ReadBinar .vi is used to read my binary files generated in the end of running of the Control.vi.
Best regards
Grigorio
Attachments:
Control.vi ‏277 KB
ReadBinar.vi ‏162 KB

Hello Zach!
First of all, I want to thank you for your kind interest on my problem!!
I must describe you the desired process with the Control.vi. There are two AI channels writing down the acceleration of a structure in two different points (for velocity reasons I use Binary Type storage for my data). One AO channel for structure sinusoid excitation (shaker) and two CO channels for controlling two solenoid valves with which I want to control my structure acceleration (minimize it as well and fast as possible)!!
In order to help the description, let’s ‘cut’ the block diagram of Control.vi into three pieces (Before While Loop – Inside While Loop – After While Loop).
In Before While Loop section, the main question is about simultaneousness. The DAQmx Start inside the Flat Sequence Structure, do you think that is necessary, ok? I want to run my experiment for 30s and to collect 6000 samples with 200 samples/s. In addition, in the CO DAQmx timing, I have set 200 samples/channel in order to be able to change the duty cycle value because of the conditions inside the While Loop. Do you think that everything in this section works well?
Inside the While Loop, firstly in the DAQmx Read, I have set 200 samples per Input Channel, which is also equal to the AI and AO Sampling rate! Before some days I have put there -1 and unfortunately the total written samples were less than 6000!! My main problem is how I can check all the read data without losing run velocity and simultaneous if one sample is >0 then it goes further to the first PID.vi (left solenoid valve) or if that sample is <0 then it goes further to the second PID.vi (right solenoid valve)!! When a sample has gone to a PID.vi, then I want to tune the duty cycle of the controller (PWM control) as well as possible in order to achieve the Setpoint value for the second AI channel. Are all these possible? If not, what do you suggest me?
In addition I compare the present duty cycle value with the previous one in order to be inside a tolerance value (let’s say 0.1). Moreover, is it correct the Case Structures where I want to share the positive and negative AI samples before going to the respective PID ?
Finally, After the While Loop, I believe that everything is OK. I just finish all the tasks.
I have to mention that I work on a PCI-6289 and Labview 8.5.
With best regards!
Grigorio
Attachments:
Control.vi ‏288 KB
equal within tolerance.vi ‏9 KB
ReadBinar.vi ‏163 KB

Can buffered digital edge detection only be performed using an external sample clock?

I am working on an application where I need to measure the speed (rpm) of a motor as it starts up using the output of its built in hall effect sensor. The sensor should output 2 pulses per revolution of the motor. My plan is to count the pulses from when the counter (counter 1) is armed to when it is up to speed. Looking at the M series manual, the CVI (v8.5.1) help, and the examples it appears that this can only be done using an external sample clock. Is there a way to route an internal sample clock to the appropriate terminal on the counter so that I do not need to add additional hardware?
I am currently using a PCI-6289, but the final application will use a CDaq-9188 chassis (using one of the the built in 32-bit counters).
Thank you for your assistance.

Thank you for your input.
However, I did forget to mention one detail of the application. I need to buffer the edge counts so that I can graph the speed of the motor as it starts up. I need to be able to acquire the edge counts at reqular intervals so that I can determine how fast the motor was rotating at each point. So far I have not been able to find an example of doing this without and external sample clock. As I mentioned, in the final application I will be using the 32-bit counters on a CDAQ-9188 chassis. The only thing I can think of at this point is to generate a pulse out of the second counter and use that as the sample clock. Will this work?

Digital Out Sample Clock Sources

Hey guys,
I am putting together an application <attached>.
Currently I have the ai/sampleclock wired to its timing VI. When I run this with highlighting on, it just goes to the read for the digital in task and waits there like it has not yet acquired enough samples. Am I right in thinking that this should result in an array of integers 2000 elements long with 1's where the line is high and 0's where the line is low?
When I swapped the clock source to being di/sampleclock I get something about my device not supporting it.
This is my first adventure into digital in, anybody have a quick hint?
Thanks,
~milq
p.s. LV 8.2 - PCI 6289
Attachments:
Wobble Test.vi ‏63 KB

First - how are you doing a difference of 2 quad encoders? Are you taking the A channel from each of 2 different encoders running at the same nominal pulse rate? I'm away from my LV PC and can't go back and look now. I've done that kind of thing before, where you configure for up/down counting and you get a measure of relative lead and lag.
Second - all the stuff I did was at home while procrastinating and is fully untested. Don't trust it to do what I said it should without testing.
Third - does it make sense to save data continuously like I tried to do for you? I've developed a rule of thumb that says, "when in doubt, store to file and defer the decision-making." The reason I goofed with the # of samples acquired & displayed was that I pictured you updating a graph representing <something> through exactly 1 engine cycle. Seemed like updating it a couple times a second would be enough.
Since this is your thread and you asked, here's the scoop on Audacity: I actually grunted through that stuff several months back. I probably did use the envelope tool, but I think I ended up applying it piecewise in several little pieces through the fade region. I couldn't make the envelope curves apply just the right shape to keep the volume constant across the fade.
It was interesting in a weird way. I'd have thought going in that nothing could be easier to mix imperceptibly than noise. It turned out that the clicks you get with no fade and the volume artifacts coming from linear fade make noise especially *difficult* to mix.
At some stage I think I mixed in some pure noise and then applied some filtering to cut out high freq hiss. I also added some low freq amplitude modulation and some low freq Left<-->Right panning. In the order of <0.1 Hz, with the two effects at frequencies without common multiples. Overall the effect isn't very noticeable (especially the panning on a boombox), but I think the slight variation works better than 100% solid repetition. Anyway, they were effects sitting there in Audacity and I figured they'd be fun to goof with.
Finally, a couple months after the first cd I found an old "Nature Sounds" tape of crashing waves on a beach. So I mixed that in with the original cd to make a version 2. The nightly scoreboard is now Fans - 2, Boomboxes - 2. I'm getting there...
-Kevin P.
Edit: put back a sentence I accidentally deleted
Message Edited by Kevin Price on 03-30-2007 03:16 PM

Error 200284-DAQmx Analog trigger

Hi,
I am trying to start data acquisition (e.g. input channels ai6 to ai10) and save it to a file based on an analog input voltage signal change (acquire whenever ai6 >2 Volts) that will work as a trigger.
I also found an example that is pretty similar to this (attached). The trigger source in my case is the first analog input channel. Following the attached example, I am always getting the error code 200284 after running the vi. Basically it gives the error after the specified timeout.
I am using PCI-6289, but the problem is I cannot use any PFI lines for the voltage trigger and have to use ai channels only for trigger.
Can't figure out what is wrong.
Any help is highly appreciated.
Thanks,
Roy
Attachments:
cont_acq_volt_analog_start.vi ‏79 KB
cont_acq_volt_analog_start.vi ‏79 KB

Yes, you must use a digital channel as your trigger source because it has a different clock. Remember, something has to activate your trigger! For instance, let's say you want to use PFI0 as your trigger...when PFI0 goes high, start collecting data.
How do you plan to control when PFI0 goes high?
It can be an external trigger. It can be another, digital, DAQmx task, where the DO line is hard-wired to PFI0. But something has to cause PFI0 to go high, in order to trigger your task.
Since you can only have a single AI task, since there's only one AI clock, you have no way of ever generating a trigger. You won't start acquiring until you receive a specific signal on an AI channel, but you won't receive that signal until you start acquiring. See why it's a no-go?
So you want to acquire for 3 seconds after getting a signal on ai6 that's >2V. So let's think this through, ok?
If we set our task to finite samples, and we set our number of samples to 3000, what will happen?
We'll acquire 3000 samples. Right? Right! If our acquisition rate is set to 1kHz, it will take 3 seconds to acquire those samples.
While we are acquiring those 3000 samples, we may (or may not!) see ai6 go over 2V. Let's say we see ai6 read >2V after 2 seconds -- that is, our second loop iteration. Since we've set our # of samples to acquire at 3000, we've already acquired 2000 samples (assuming a 1kHz sample rate). That leaves us 1000 samples until our task expects to terminate (after which, you'll get an error). That's not 3 seconds worth of data, is it?
What if ai6 never goes >2V within our 3000 sample window? Now you haven't collected anything, and your task will throw an error if you try to collect beyond 3000 samples.
So no, setting our samples to finite and specifying the collection of 3000 samples isn't going to work, is it? Clearly not. That's 3 seconds' worth of data, all right, but it may not be the right 3 seconds' worth of data. Since you don't know when ai6 will be >2V, you need to continuously acquire samples.
Do you suppose we could do something with keeping track of time? Specifically, the time at which >2V was detected? Compared to the current time? And take action based on that? The logic for your case structure will become slightly more complex.
Do you know about shift registers? I'm not trying to be insulting, you said you were new and I'm not 100% sure of how new you are. :-)
You seriously do need to take your Write to File out of your DAQ loop...please look into producer-consumers, or you'll be right back on this forum asking us about buffer overflow errors. :-) Also, beware of the Write to Measurement File Express VI...you don't have a file path wired in the code you showed, so it's going to pop up a dialog box every time it's called, asking for a file path.
If you really want to learn LabVIEW, you will get rid of all Express VIs in your code. At the very least, you need to understand exactly what they do and how they work. Writing code that you don't understand is only going to cause problems later

How to update NIDAQmx driver in Labview RT?

Dear members,
I have a problem to make my NI PCI 6289 card working in Labview RT.
Namely when I run the self test appears an error number -88716.
The screenshot says that the NIDAQmx drivers on the host and on the target are different.
It suggests to update the driver to correct the error.
Now I have checked. On the host I have the NIDAQmx8.5.1f2 driver on the RT target the NIDAQmx8.5.1.
The question I want to ask is. How can I update the driver on the RT target to the other version?
Since I have installed the RT system just yesterday I can't imagine that I have done some updates on the host which are not done on the target.
Someone has an idea how to override the error?
Thanks
Principiant
Solved!
Go to Solution.

The NI support solved my problem here is the link with the solution.
http://digital.ni.com/public.nsf/allkb/A47734CC1E03922186257435004D0C49?OpenDocument
In the download page, just download the first link NIDAQmx 8.7.1 not the runtimes at the end of the page.
Thanks for the help .
Bye
Principiant

Counter as a digital Trigger

Hi,
I wrote a programm for a PCI 6289. It realises a triggered analog voltage in- and output with the internal counter. With this PCIcard I can use the trigger directly with the PFI12 pin and everything is fine.
Now, I transfered it to a PC with a PCI-MIO16E1 (6070E) card.With this card the Counter isn`t linked to PFI. My question is: What can I do to bring the card to use the counter correctly. I tried already with "connect terminals" but I`m not able to select the counter in that configuration. Has someone a good idea?
Greeting Daniela

Hi Daniela,
I think the easiest way ist to wire it directly from counter out to one PFI, isn't it?
Furthermore you can do it this way maybe:
Internally Routing Counter Signals in LabVIEW
http://digital.ni.com/public.nsf/allkb/8A85E97855EDADC98625730C00065F58?OpenDocument
regards
Tobias

Synchroniser mesure analogique, tachymètre et GPIB

Bonjour,
J'ai une carte PCI-6289 que je voudrais programmer avec Labview 8.2 / DAQMX.
Sur cette carte je voudrais faire une acquisition bufferisée de mesures analogiques et d'un signal TTL issu d'un tachymètre (mesure de vitesse) en même temps.
Est-il possible de réaliser cette fonction avec cette carte et si oui existe des exemples ?
En plus du mode cité ci-dessus j'ai un autre mode de mesure où il est question de mesurer de façon synchrone :
- Mesure analogique sur carte PCI-6289,
- Mesure tachymètre sur carte PCI-6289,
- Mesure GPIB issu d'un analyseur de puissance.
Ces mesures doivent se faire à 1 Hz
Le vendeur de l'analyseur de puissance m'a indiqué que l'appareil disposait d'une entrée Trigger.
Quel est le meilleur moyen pour synchroniser tous ces équipements ?
D'avance, merci pour votre aide.
CAPRA

Bonjour,
Merci pour votre réponse.
Le Tachymètre génére vraisemblablement une fréquence que je dois convertir en vitesse.
J'ai vérifié dans max en créant une tache DaqMX s'il m'étais possible de "Triger" la mesure (voir copie d'écran en PJ), et helas je ne trouve rien à ce sujet.
L'autre inconnue pour moi est de savoir si je dois utiliser une horloge externe à 1 Hz ramener à la carte PCI-6289 puis à l'appareil GPIB, pour synchroniser tout le monde (Analogique/Vitesse/GPIB) ou si je dois utiliser l'horloge interne pour déjà synchroniser Analogique/Vitesse et ensuite sortir cette même horloge si elle disponible sur le SCB68 pour qu'elle soit exploitable par l'appareil GPIB...
Merci.
CAPRA
Pièces jointes :
DaqMx_Freq_Task.JPG ‏46 KB

Acquisition bufferissée tachymetre et mesures analogiques

Bonjour,
Voici ma configuration Logicielle : LabView 8.2 - DAQ-MX - Windows XP SP3
Voici ma configuration matérielle : Carte PCI-6289 - Tachymètre relié sur Compteur 0 (PFI8) - Sondes températures relièes sur Voies 0,1,2 RSE
Le tachymètre génére 52 tops / TourMoteur et le moteur peut touner à 20000 tr/min soit 17 333.33 impulsion par seconde. Il n'y a pas de bit de sens de rotation.
Mon but : réaliser une acquisition bufferisée simultanée Tachymètre (convertie en tr/min) et 3 températures.
D'après vous, quelle est la meilleur méthode pour réaliser cette fonction ? Je ne trouve pas d'exemple labview permettant de réaliser cette fonction. Existe-t-il une note d'application ? Comment dois-je connecté mon tachymètre à ma carte.
D'avance, merci pour vos réponses.

Bonjour,
Attention à la notion de "simultanéité". Une carte de la série M ne peut pas faire d'acquisition analogique simultanée sur plusieurs voies car elle ne possède qu'un seul C A/N pour toutes les voies d'entrée analogique.
Ainsi, je pense que par "simultanée", vous vouliez en fait faire l'acquisition de température sur 3 voies dans un seul et même programme?
Dans ce cas là, vous pouvez le faire en utilisant par exemple l'Assistant DAQ dans lequel vous allez paramétrer vos 3 voies Analogiques avec la même fréquence d'échantiollonage et travaillant sur la même gamme.
Pour le tachymètre, effectivement le meilleur moyen sera d'utiliser le compteur et de faire du "comptage de front" directement.
Cordialement
David S.| Certified LabVIEW Associate Developer
National Instruments France
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"Ecrire un fichier de mesure" est limité à 10000 points ????

Bonjour,
Je souhaite enregistrer des données issues d'une acqusition (PCI 6289) et j'ai remarqué que le VI "ecrire un fichier de mesure" limitait l'enregistrement des données à 10000 points exactement. Est-ce normal ? y-a-t-il un moyen d'enregistrer plus de points dans un seul fichier ? (J'avais dans un premier temps utilisé le VI enregistrer dans un fichier tableaur, mais sous excel -avant la version 2007- on est limité à 65536 lignes. Ce qui ne suffit pas encore....).
Merci pour vos réponses !

Hello.
To get an answer on this part of forum, you should post in English.
The french part is here.
Could you tell us more? Which version of labview do you use / explain us what do you want to do?
Thanks.
Regards.
Romain D.
National Instruments France
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Changing filter cut off on M series cards

I want to sample 32 channels with the M series 628x series cards. But at the maximum sampling rate that would afford me a 15Khz sampling per channel. To avoid aliasing I need an analog filter at 5 KHz. The M series card only offers a 40 Khz filter. Is there anyway to change this filter's cutoff (-3db) to 5 Khz? Any suggestion is greatly appreciated, but I'd like to avoid building a 32 separate analog filters in front each channel.

Hi,
I'm really worry about this issue.
Our customer has a PCI 6289 and he bought it becuase on the catalogue it said: "Programmable lowpass filter"
http://sine.ni.com/nips/cds/view/p/lang/en/nid/14115
He wants to use the antialiasing filter option with a cutoff frequency of 1KHz.
The answer you wrote means that he cannot use any cutoff frequency, just 40kHz.
So , why it is written "Programmable lowpass filter"?
what is or are the ranges of the "Programmable lowpass filter"?
Why isnt documented on the M series specification?
Thanks
Dalia
Dalia Russek
Application Engineer Manager
National Instruments ISRAEL Ltd

Generer un signal arbitraire avec differents frequence

Bonjour,
je dispose d'une carte NI PCI 6289 Serie M,
je souhaiterai generer 2 signaux arbitraire mais qui ont des frequences differentes pour commander un chargeur de batterie.
Par exemple pour un signal : une rampe suivie d'une marche d'escalier.
J'ai tout essayer mais je n'y arrive pas, pouvez vous m'aidez ?
en vous remerciant d'avance,
F.

Ce que j'entends par duree modifiable, c'est que si je veux la duree d'une seconde mon signal ait cette duree. J'ai deja essaye de modifier mon vi mais pour le moment jen'arrive pas a arrive a mes fins. merci de votre aide
Pièces jointes :
frequence_modulee.vi ‏27 KB
tableau de modulation.vi ‏21 KB

Pci-6289 delay

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