Rapidité d'execution PXI vs PXIe

Bonjour,
J'ai un souci de rapidité d'execution entre 2 type de chassis sur lesquels j'ai le même VI qui tourne!
Je réalise une acquisition de 2MS/s avec une architecture producteur consommateur. Je stocke directement dans une file d'attente mes échantillons IQ qui sont transmis à la boucle consommatrice pour réaliser les opérations de démodulation.
Mon problème est que ce VI tourne mieux sur le chassis PXI équipé d'un controleur avec processeur 2Ghz et RAM 1Go que sur mon chassis express équipé d'un controleur double coeur et d'une RAM de 3,37Go!!!
Le chassis express n'arrive pas à traiter mes échantillons en direct il est obligé de les stocker dans la RAM et donc ça augmente énormement le temps de traitement alors que le chassis standard réalise la démodulation en live sans remplir la RAM!!
Je presice que les OS sont, sur les 2 controlleurs, des windows XP SP2 et que les VI sont strictement identiques!!!
Je ne comprend pas
help please
cordialement

Bonjour,
Tout d'abord, étant donné que vous n'avez pas le même matériel (je parle des cartes connectées sur vos chassis), il est très probable que vos VIs ne soient pas exactement les mêmes.
Ensuite, avoir un processeur utilisé à 100% en permanence n'est pas une bonne chose. Ceci est donc un point à corriger dans votre (ou vos) Vi(s). Si sur votre chassis PXI, le processeur tourne à 100% c'est que vous utilisez votre système à plein régime. Selon vos besoins, vous devez adapter l'implémentation de votre code LabVIEW. Quoi qu'il en soit, cadencer votre boucle d'acquisition est fortement conseillé. Forcément, cela allongera un peu votre temps total mais votre matériel n'acquérira plus au maximum de sa capacité (et peut être de façon irrégulière si le temps de traitement des données varie au fil des itérations de votre boucle d'acquisition).
Vous devez en fait adapter votre implémentation en fonction de vos besoins, c'est à dire que si vous voulez acquérir des données de façons rapide avec un très faible intervalle de temps entre les acquisitions alors la fonction "Attendre un multiple de (ms)" correctement paramétrée devrait ralentir de façon minime votre temps d'exécution. Si toutefois acquérir 100 données par seconde par exemple est suffisant, vous pouvez diminuer la fréquence d'acquisition et donc économiser de la ressource processeur.
Il en est de même pour votre file d'attente. Si votre priorité est de récupérer toutes les données alors vider la file d'attente est important. Si toutefois, lors de l'arrêt de l'acqusition, votre priorité est d'arrêter l'exécution aussi rapidement que sur votre contrôleur PXI alors vous pouvez abandonner le traitement des données restantes dans la file d'attente.
Cordialement,
Jérémy C.
National Instruments France
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Travaux Pratiques d'initiation à LabVIEW et à la mesure
Du 2 au 23 octobre, partout en France

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Can i use PXIe-1073 with an embedded PXIe controller PXIe-8108

I have a PXI express chassis PXIe-1073 with an integrated controller MXI-Express controller PCIe-8361. I now want to use the chassis as a standalone system with an embedded controller.
(a)Can i use PXIe-1073 chassis with PXIe-8108 embedded controller
(b)Can i use a windows based laptop to control the PXIe-1073 via the PCIe-8361 integrated controller.

Hello kanad,
The PXIe-1073 is a MXI-integrate chassis. This means that the MXI card that would normally go into the controller slot (slot 1) is built into the chassis. The PCIe-8361 or Expresscard8360 are placed into the desktop or laptop, respectively, and connect to the chassis. The cards in the PXIe-1073 then appear as if they are part of the desktop of laptop.
Since the controller is built into the chassis, the PXIe-1073 does not have a slot 1. Controllers, such as the 8108 can only be plugged into slot 1. Therefore, the PXIe-1073 can only be controlled by the desktop or laptop MXI link. It cannot run standalone with an embedded controller.
Consider reading page 1-3 and 1-6 in the manual below:
NI PXIe-1073 User Manual and Specifications
Regards,
George T.
Applications Engineering Specialist
National Instruments UK and Ireland

Pushing the limits of continuous high-speed DAQ + processing, with PXI-6115 + PXI-8360

Hi all,
I'm trying to do continuous high-speed data acquisition + processing. I currently have:
Chassis: PXI-1042Q
AI card: PXI-6115 (x2)
Link: PXI-8360
PC CPU: Intel Xeon W3503 (dual-core, 2.40 GHz)
RAM: 4 GB
The idea is to continuously grab 8 channels' worth of analog inputs, scan for "events", and if found, log the events to disk.
My client would like to use the maximum sample rate of 10 MHz, but I found that above 5 MHz, DAQmx Read.vi can no longer keep up (e.g. at 6 MHz, it takes 110 ms to read 100 ms' worth of data).
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I'm not sure how big the data is. PXI-6115's ADC is 12-bit. Does that mean each datum transferred through the MXI cable is 1.5 bytes? Is the data padded? Or is it 8 bytes per datum, because Dbls are being transferred?
2) The CPU
In Resource Monitor, I notice that the CPU usage is 0% at 60 kHz, 8% at 61 kHz, and 50% at 70 kHz (meaning that one core is maxed out). I'm surprised that it keeps up all the way until 5 MHz though.
What causes this high CPU usage? Is it due to the conversion of the data into 1D array of waveforms?
3) Something else?
Have I missed something completely? Is what I'm describing even possible?
Thanks in advance for any advice!

Hello,
Each sample will take up 2 bytes, 12 bits data + 4 empty bits. so the PXI-PCI 8360 is only able to transfer a maximum of 50S/s in this case.
Also, because the PXI bus is shared among all of the cards, two PXI 6115 cards will be trying to transfer 80MS/s or 160MB/s.
Finally, since the PXI 6115 are DAQ family cards, their specifications aren't really written for continuous data acquisition at the upper end of their sample rate, but I'm interested to know if you can get up to 10MS/s with only one card operating at a time?
-Jim B
Applications Engineer, National Instruments
CLD, CTD

CTR works with PXI 8196,PXIe 8102, fails with PXIe 8100 - why?

My client has reported a problem.
For years he has used a PXI 8196 RT Controller with PXI 6602 Counter card and my software has given good results. They have 20+ of these systems and they have worked well.
Now they are moving to PXIe 810x controllers, for cost reasons.
WIth a PXIe 8102, the same code also works perfectly, measuring total counts over a period, as well as instantaneous frequency.
With a PXIe 8100 - the exact same code reports DIFFERENT answers. The reported frequency is always 1% HIGHER than actual (For example, a known 4500 Hz input is reported as 4500 Hz on 8102, but as 4545 Hz on 8100.
This happens on any channel, and swapping just the controller will make the problem come and go.
Here is the CONFIGURE code, where the channels are set up (again, this has worked for years).
Here is the SAMPLE code:
Basically the CONFIG code configures the thing to count edges. I do this because they need an accurate count over a 20-minute period, in addition to instantaneous frequency readings.
The AVG TIME is a user-settable number defining how long a period to average, when showing the "instantaneous" frequency.
So, I create a buffer for N samples, corresponding to that period.
At SAMPLE time, I read the counter. I replace the oldest value in the buffer with the newest, then subtract the newest - oldest to get the total counts in the sample period.
The PULSES PER COUNT item is a scaler, to account for a 60-tooth wheel, or something.
So, this same code has worked perfectly for years, until I plug an 8100 code in. Then the result changes by 1 %, and EXACTLY 1%?
The CPU burden on the bad controller is 31%.
Any ideas?
Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com
Blog for (mostly LabVIEW) programmers: Tips And Tricks

Well, the controllers are not in my own hands. I have an 8196 controller and on that, the CPU time is between 2 and 4%.
But the 8100 and 8102 controllers are in my client's hands.
I haven't gotten any hard timing numbers other than I saw the 31% figure reported on the video monitor.
It's hard to believe that it would be EXACTLY 1% if it was CPU overburden.
My software includes a calibration facility; here is a run from the good 8102:
Here is a run from the 8100:
This was with a reference digital freq generator. You can see the one case where everything is within 0.1 Hz.
the other case has everything EXACTLY 1% higher. My only explanation is that the scan engine is running 1% slower.
Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com
Blog for (mostly LabVIEW) programmers: Tips And Tricks

PXI-6115 & PXI-6143 on Same Computer, RDA's Future

Today I installed several PXI-6115 cards and realized that they are only
supported with traditional DAQ under version 7.2. This is OK for now
because I'm already limited to traditional DAQ to be able to use RDA.
However, I was considering adding the new inexpensive S board, the PXI-6143,
to my system. According to the list of supported boards this board is only
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1. How can these two S boards be used by the same system if programming with
LabVIEW?
2. Any guesstimate on if or when the PXI-6115 will be supported by DAQmx?
3. Any guesstimate on if or when RDA will be supported by DAQmx? RDA
(remote data acquisition) is an extremely valuable DAQ method and I hope it
will be supported by D
AQmx soon!

Hello,
You are correct about the support of both boards. The 6143 is only supported in DAQmx, and the 6115 is only supported in Traditional DAQ. Here is the best that I can do for the other questions.
1. You can program each card in a different driver. This is not a problem at all. The only conflict occurs when you try and program a card in both drivers at the same time. Such as trying to do analog output in Traditional DAQ and analog input in DAQmx.
2. This is internal information only. For further information I would contact your local sales representative, she/he might be able to assist you further.
3. Again, if and when is internal information. It is not currently supported. At the moment, you can use remote front panels, or create y
our own server/client VIs to control a remote DAQ board.
These are excellent pieces of feedback for our R&D department. I highly encourage anyone who reads this thread to submit product feedback using this link.
Best regards,
Justin T.
National Instruments

Bluetooth connectivity for PXIe-1071, PXIe-8133

Hi, There are about 24 numbers of NI PXIe-1071 chassis with PXIe-8133 controllers in our lab. I would like to interface a Bluetooth device (EEG and ECG monitors) with the DAQ. The DAQs are running Windows 7 and LabVIEW.
How would you suggest I connect the Bluetooth devices to the DAQs?
If I buy Bluetooth dongles that fit via the USB is that a good solution?
Thanks.
Philip

Hi PKP,
Since your controllers are running Windows 7, they function just as a normal computer would; therefore the USB ports would behave just as a desktop would. You could load the drivers onto the controller and collect data from the bluetooth device that way. Do you have software to read the EEG and ECG signals into LabVIEW?
Best,
tannerite
Tannerite
National Instruments

NI DAQ card not find PXI-4070/PXI-6602

In the course of daily use, I found the acquisition card is often missing, does this problem how to solve?

The Version of your NI-DAQmx Driver?
--> 9.1.5
Whichever Operation System are you using?
--> It wasn't working on Windows XP. I now installed Windows 7 (32 bit) and it is still not working.
Do you try to set the PXI-6122 in another slot of your Chassis? What happend then?
--> The problem is not related to the PXI-6122 card, but rather to PXI cards (and maybe HP computers) in general, as I found out in the meantime:
http://forums.ni.com/t5/Multifunction-DAQ/DAQ-cards-not-selectable-although-listed-in-MAX/td-p/12426...
When I put the card into another slot (there were only two free slots), the PC didn't boot anymore.

NiDMM IVI Error Converter Fails at launch after changing from PXI Chassis PXI-1042Q to PXI-1031. None of the congiguration setup parameters work so the VI won't work

I have changed a PXI system from the development system with a contoller PXI-1042Q to a PXI-1031 chasis using MMI-4 comunications with a XP based commputer. When I try to run my application none of the configutation files for niDMM load. the error I obtain is: "LabView Load error code 3 could not load front panel" Also niDMM IVI Error Converter.vi for Powerline Frequecny, auto zero, ADC calibration,Measurement Digits, offset comp Ohms, multi point, Meas complete dest, Meas complete slope, and fetch multipoint won't load.
Does anyone know what my problem is. I have made sure that the handles I am using in the software match the PXI chassis handles. When I search for the niDMM IVI Error Converter.vi I can't find it on either system.

Hi Foxy-
One thing to make sure is that the driver version on the new system is not older than the driver on the old system. Make sure you have at least the same versions between the two and all should load just fine.
I hope this helps. Let us know if you have any additional questions.
Gary P.
Applications Engineer
National Instruments
Visit ni.com/gettingstarted for step-by-step help in setting up your system.

I got Internal Software Error -223044 with my PXI-4472, PXI-1033 and NI expresscard-8360 DaqMx 8.8

When i running the self test of the board in MAX i got error -223044, anyone that has some ideas??
STALT

Hey Stalt,
This particular internal error begs me ask a few questions.
1) Has this 4472 ever been used with DAQmx?
2) How old is this 4472? When was it bought from NI? Can you give me the revision letter of the board? That is found by looking for a number printed on the board that usually begins with "ASSY", then there are several other numbers/letters, but the one letter I care about is the letter right before the "-" So it would look like ASSY11111111E-01 so the revision would be "E"
3) Do you have another PXI system (with DAQmx) that you can initialize this 4472 in?
Let me know
-gaving
Software Engineer
National Instruments

PXI-8630, PXIe-1078 non identifiés dans MAX

Bonjour,
J'ai un chassis PXI-1078 contenant des PXI (4110, 4130, 4132, 2532) et contrôler par un pc portable en utilisant PXI-8360.
Mon Problème est que sur le gestionnaire des periphériques le pont PCI vers PCI standard ne montre aucun problème mais, sur MAX quand je veux ajouter un chassis j'obtient dans la liste de "remote controller" : NI PXI 8310 au lieu de 8360. En plus de ça mon PC ne detecte pas les PXI existants dans le chassis comme des nouveaux periphériques dans le géstionnaire des periphériques.
Que puis-je faire pour résourdre ce problème.
sachant que j'ai effectué tous les mis à jours possible qui existent sur Ni support:
MAX --> 5.0
NI PXI Platform services --> 3.0.1
NI VISA --> 5.1.1
en plus des update des drivers pour le mois d'Aout
Merci d'avance
TheShadowx
Solved!
Go to Solution.

Hello,
And thank you for posting here.
What is your OS, your LabVIEW version and the model of your computer?
Did you respect the order of Installation for our products?
http://digital.ni.com/public.nsf/allkb/779E54A45478FA2C86256D0500774FCB?OpenDocument
Is your BIOS version not to old? It could fixes some PXI problems. If you BIOS is updated, you can try the NI MXI-Express BIOS Compatibility Software 1.4 which is still in Beta but which work fine. You can find it here :
http://digital.ni.com/betaprogram/mainbetacust.nsf/main.htm
Here two links to other posts where the problem is quite similar. There as useful links contained in those posts :
http://forums.ni.com/t5/PXI/Express-card-MXI-laptop-compatibility-1033-and-8360/m-p/697994?requireLo...
http://forums.ni.com/t5/NI-Applications-Engineers/PXIe-1073-via-MXIe-8360-not-visible-in-MAX/td-p/14...
Regards,
Jérémy C.
National Instruments France
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Travaux Pratiques d'initiation à LabVIEW et à la mesure
Du 2 au 23 octobre, partout en France

PXI 5600 + PXI 5124 + PXI 5112

HI,
Can I make RF Vector Signal analyzer by using NI-PXI 5600 RF downconverter with digitizer NI-PXI 5124 and NI-PXI 5112 digitizer?
thanks
TM

Hi TM -
Nick is right. Although the 5124 would technically work with the 5600 as a VSA, the programming would be excessively difficult. You wouldn't be able to use the NI-RFSA driver with that combination, which leaves you coding each device separately and getting them to cooperate manually. For an example of how complex this task is, download a copy of NI-5660 and open up any of the top-level VIs.
Moreover, because the 5421 doesn't have the Digital Downconversion (DDC) feature that the 5441 has, your sampling rate will be horrible. The 5600 brings RF down to a 15MHz center frequency. This means that your highest spectral component will be up to 25MHz, and you'll only be able to sample it at 4x. This will make your resultant waveform very ugly, and you won't be able to do any spectral measurements or I-Q decoding on it.
The 5114 falls prey to the same limitations as the 5421. Becuase of this, we add a DDC to the 5441 and use that as the digitizer for the VSA package.
David Staab, CLA
Staff Systems Engineer
National Instruments

Using PXI-5431and PXI-1411 to test MPEG-2 encoder/decoder

I am looking into a way to test an MPEG-2 encoder/decoder. I have found the PXI-5431, that can generate a NTSC signal which is what I need and the PXI-1411. So, I guess my question is: would this be a good set up to use the 5431 to generate a signal and the 1411 to acquire the signal and do some comparisons to the two. Has anyone done this type of testing? What type of comparisons could be done to the two video signals to verify signal quality(I know very little about video signals)? Or maybe acquire using the PXI-5122?
Thanks,
Brian

Hi BrianPack,
I have some questions. Please be much more detailed and specific in your next response. Try not to use pronouns. Instead, every time you want to use the word "it" or "card", instead use the proper names, such as the "PXI-5122".
What card are you referring to in your first sentence?
When you say (it) "can be configured to decode and encoded MPEG video", do you mean to say you are attempting to encode analog video?
With all the MPEG encoding and decoding, which cards are you referring to? Your two cards, or two NI modules?
When you generate into the encoder, are you wanting to generate from the NI 5431? If this is true, what video standard are you wanting to use?
The Frequency Response, Video Resolution, SNR, and composite signal amplitude measurements should be available with the NI 5122 and MicroLEX VideoMaster. I'm not sure about the NI 1411 because I only support NI's Modular Instruments, but here are the specification sheets for VideoMaster:
http://www.microlex.dk/products/video/videomaster-component.pdf
If you want more information on the NI 1411, it would be best to post a message on the IMAQ/Vision forum. For now, please respond with more specific information and I'll be happy to assist you!
Chad Erickson
Applications Engineer

PXI-8170 & PXI-1025

Hi,all,
Ihave some trouble to install the PXI-8170 in chasis 1025.
What I have done are:
1) Configure the switch S1 and S2 to surpot internal keyboard and mouse. Configure S3 to support 600x800 display.
2) Configure BIOS "LCD&CTR" as LCD (I have tried the others too).
3) Set the screen of the win98 as 800x600.
However, I still connot see anything in the LCD.
Why? How to solve it? Do I need to update the Flash BIOS? Where can I get it?
Tanks a lot.

You probably do not need to flash the BIOS.
In all liklihood, you just need to set up your video driver to support LCD. It will be slightly different for Windows 98 (sorry, I only have Windows 2000 at my disposal at the moment), but the basic procedure is as follows:
1) right-click on the desktop and select "Properties"
2) Go to the "Settings" tab and select "Advanced..."
3) Go to the CHIPS tab and make sure you have either "LCD" or "BOTH" (I recommend "BOTH", at least to get everything up and running) selected.
4) Select "OK" and you should be able to see an output on the LCD screen of your 1025
Trey Hamilton
National Instruments
Applications Engineer
http://www.ni.com/support

PXI-1025 & PXI-8170

Dose chasis PXI-1025 support controller PXI-8170?
Thanks

Yes, the 1025 MegaPAC does support the 8170 controller. I have included a link to our knowledge base that holds the documentation describing the procedure for configuring the 8170 and 1025 to work together.
http://digital.ni.com/public.nsf/3efedde4322fef19862567740067f3cc/37d5433f1a4160218625685d00815166?OpenDocument
Best Regards,
Amy Hindman
Applications Engineer
National Instruments

About PXI-6220 PXI-6221

We want to use PXI-6220 or PXI-6221 to design a system. And we will use the CVI or Labview, but we cannot find the PROGRAMMING MANUALS of PXI-6220 or PXI-6221.Where can I get them? Thanks!

Hi wenyan,
You can program both the PXI-6220 and the PXI-6221 using the NI-DAQmx driver. The following tutorial is a very helpful:
Learn 10 Functions in NI-DAQmx and Solve 80% of Data Acquisition Applications
Also, both LabVIEW and CVI come with various data acquisition shipping examples (Help >> Find Examples). I suggest using those as starting points.
If you've installed the DAQmx driver, you should be able to find DAQmx Help from (assuming you're using WindowsXP) Start>>Programs>>National Instruments>>NI-DAQ
More information on the DAQmx functions can be found:
NI-DAQmx Help (User Manual)
Hope this helps,
Lesley Y.

Rapidité d'execution PXI vs PXIe

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