Time in LabVIEW DAQ Assistant and Write LabVIEW file
I would be extremely grateful for your assistance in helping me understand the timing in LabVIEW.
Here are the details of the system. The data acquisition is done using a simple LabVIEW 8.2 based program consisting of a DAQ Assistant VI and a Write to Measurement File VI, which writes data in TDM format (binary with XML header).
The hardware consists of a 1042Q chassis that contains 2 PXI-6133 cards. 16 transducers are connected to these 8 channel cards. The chassis is connected to a PC by means of MXI-4 fiber optic cable and a PCI-8336 card.
I would like to sample all 16 channels simultaneously at 500 kS/s for 2 secs. or 1MS/s for 0.5 secs.
When the signals were sampled at 500kS/s x 2secs., the time column looks like this when opened on DIAdem.
Serial# Time Time(in secs. when displayed in number format with 8 decimals)
1 07/10/2007 00:09:42.1406 63351158982.14060800
14 07/10/2007 00:09:42.1407 63351158982.14069760
64 07/10/2007 00:09:42.1408 63351158982.14080000
109 07/10/2007 00:09:42.1409 63351158982.14090240
The time does not change from serial 1 to 13, and only at the 14th row does it change, after which it remai...Driver paths in Labview no DAQ Assist
Hello, I am new to LabView and I recently installed the student edittion of Labview 8.5. For some unknown, crazy reason i did not install this to the default drive path, ie C:program files\ etc but to another drive on the computer, ie E:.Now the problem is that i need to use the DAQ Assistant for my USB-6008 board. I have installed the the NI drivers which came with it and the board works fine in MAX, recognises it and i can get temp readings from the circuit i built. When I try to use Labview I cannot find the DAQ Assist in the Input section on the palette.Could some please help me. My mate gave me a file he did on his Labview but when i try to load it starts looking for DABmx Control Task and a whole host of other files.Much appreaciated for any help in this matter.Lee
Its cool to install things into different places on your drive - sometimes its essential. there is also an easy solution to your problem. What you have at the moment is different drivers and programs spread around your computer with no links to each other so they are unable to reference each other. To create these links yopu will need to mass compile.
Within LabVIEW go to the tools menu and then select Advanced>>Mass compile. This will bring up a window that will allow you to select a directory. Select the directory that you have saved all your DAQmx drivers and then select mass compile.
This should allow you to see all the VIs in the correct menus within labVIEW.
I hope this is of some ...struggling how to set up 2 daq assist on labview in the same VI
hope someone can help me out
I am currently using the scxi 2345 with some SCC FT01 feed through modules, these are just to record some voltages from some transducers.
What I am struggling with is setting up 2 daq assist on a single VI, it is coming back with a error stating specified resouce is reserved and then a window saying learn more about automatic handling. How would I also have these 2 values logged on the same graph or chart?
Anyone any ideas how to set these up.
I ideally want to have 3 daq assist in the same Vi but not sure if this is ...What are my options for deploying DAQ assistant with a built LabView application.
I am currently working on a LabView application which I intend to build with LabView Application Builder and deploy on a couple of computers within the company. The application's end-users will need to create and edit DAQmx scales and virtual channels using the DAQ assistant once the application is deployed. It looks like we (or anybody else) is only licensed use use the DAQ assistant to create scales and virtual channels if there is also a valid license for LabView, LabWindows, or Measurement Studio also installed on the computer.
(See <a href="http://digital.ni.com/public.nsf/allkb/402D2EB45062FBC486256DD600634695" target="_blank">http://digital.ni.com/public.nsf/allkb/402D2EB45062FBC486256DD600634695</a> for the licensing restrictions message that pops up if you create a scale without having LabView, LabWindows, or Measurement Studio installed.)
Is there an option to buy/obtain a deployment license which would allow my end-users to use the DAQ assistant without purchasing a LabView, LabWindows, or Measurement Studio development system license which they would not otherwise need or use?
That link does not apply at all. The link was referring to using the DAQ Assistant with an evaluation (unlicensed) version of LabVIEW. As a matter of fact, you cannot use the DAQ Assistant at all with a built application. The only way to start up the DAQ Assistant ...DAQ assistant with AT-MIO-16E-2 board LabVIEW 7.1
I'm just trying to get started with some simple data acquisition, to learn the basics about it and hopefully be able to do more advanced stuff later.
I'm running LabVIEW 7.1 on Windows 2000, with an AT-MIO-16E-2 board connected to a NI TBX-68 which currently only has one thermocouple connected on channel 0. When I open MAX, I can see the board and if i press on test panels, i'm able to see the channel and it reacts if I touch the thermocouple. Therefore that seems to be all right.
But then if I try to put in the DAQ assistant into a VI and try to set up a task, it always says that 'no supported device could be found'. Does anybody around here know how to go about solving this problem?
Thanks a bunch,
did you try to program this function by yourself with the DAQmx vi? Maybe this works.
thanks for your quick reply! I don't really know how to go about programming it in the DAQmx vi... can you give me some advice about how to do it?
here is a simple example. Maybe you can change it for your use.
Thanks Mike. Can you save files for older labview versions in labview 8? I'm running 7.1 so can't open it up. :S
sorry for that, here is a picture.
...Daq assistant express vi freeze error Labview 7.0 express
I'm using Labview 7.0 express software. I cannot use DAQ assistant because it freezes when I click on it and drag it to the labview page. I have not connected any device so there is no interference. While all other express vi's work DAQ assistant vi doesnot work. Could you please help me?
Thanks for this quick reply;
I checked it and DAQ-mx is already there but the freezing of the DAQ assistant still contiues. I can start the intrument assistant but the DAQ assistant vi does not work. It locks up LABView 7.0 when I try ...DAQ assistant!?
I can't seem to get my DAQ to work!? I have connected a DAQ-9172 (USB) with a NI 9265 module (4-20 mA output). I have installed it at it seems to be OK (it checks out ok in MAX)..... but when I try to use the DAQ assistant in Labview I get the following error? (see attachment) what do I do wrong?? I dont think there are a lot of things to chaneg in the DAQ assitant!?
You need to increase the buffer size for your AO operation. What you need to do is convert DAQ assistant to DAQmx code(Right click DAQ assistant->Generate DAQmx code). Then use "DAQmx Configure Output Buffer.vi" to override the automatic output buffer allocation.
Here is a KB-link that adresses this issue: <a href="http://digital.ni.com/public.nsf/websearch/34B9B5A331DE0E18862571F80072FAEA?OpenDocument" target="_blank">http://digital.ni.com/public.nsf/websearch/34B9B5A331DE0E18862571F80072FAEA?OpenDocument</a>
thanks for your answer! I'm a newbe in labview and I have a NI cDAQ-9172 (USB) and a current out module (NI9265)... Can someone direct me to a descriping "how to - step by step" manual on how to write data out! It not as simple as a thought :-)
I'm running LabVIEW 8.5. I'm trying to follow the NI example titled "Using the DAQ Assistant to Automatically Generate LabVIEW Code." My problem is the DAQ Assistant does not show up on the Express/Input palette.
I have something called the Instrument I/O Assistant, does the DAQ Assistant now fall under that?
The Daq assistant should show up in both the signal express category in the functions palette and the Daqmx palette. If you type "daq assistant" into the search on the functions palette you should find them.
Regards,Message Edited by mickeyw on 08-05-2008 03:18 PM
Unfortunately it doesn't show up. We have the full NI Developers Suite of software, do you know what disk that would be on?
Ok. Do any of the express VIs in the palette show up? If not it maybe that something wasn't installed directly, in which case re-installing may help. There should be a daqmx disk with the developers suite - the daq assistant should also show up in this sub-category of the functions palette.
Lots of express vi's show up on the Express palette. My understanding was that I'd find the DAQ Assistant under Express/Input palette, but its not there. I do have an installation CD called NI-DAQmx Base which I installed, but it did not fix the issue.
DAQmx base is not the same thing as DAQmx which is what you need for the DAQ Assistant. What OS are you using? If a non-windows, then installing DAQ...ni usb-6009 daq assistant not read as daq, but just as USB
I have some problems in configuring the NI usb-6009 device. the DAQ assistant of labview can't recognize it (we have downloaded the NI DAQmx 1.3). MAX sees the devices like usb and not as a DAQ. have you some suggestion for us?
...DAQ assistant to array
I'm trying to write voltage from the daq assistant into an array and then store this in a file. All I get in the file is the initialized array. I just want the voltage once per second to be read into the array and then after 20 seconds have an array to store in a file. I've tried to change the sampling rate and add in a wait until vi, but this doesn't work either. Can anyone tell me what I'm doing wrong. Thanks.
change the datatype of your array to "dbl", then you get the real values. See attached your modified vi.
...DAQ assistant #4
I am using LabView 8.2 and I was trying to find out the maximum sampling rate of my data-acquisition device. I have the signal conditioning module of SCXI 1102 which has a sampling rate of 333 kHz and a USB digitizer module of SCXI-1600 which has a sampling rate of 200 kHz. When I was experimenting with the various sampling rates, I got an error 50016- The specified window type is not valid or is inappropriate in the context of the current device configuration. But the error goes when I power off the chassis, then turns it on and try again. How can I avoid this?I need to write the acquired data into a file and it seems to me that this is where the problem lies- I cannot go beyond a particular sampling rate as the writing slows down the whole process.I found that the method of data acquisition in the LabView examples is faster as compared to the DAQ Assistant. Any suggestions?
In what file format are you writing, it is best to use a binary (binary or TDMS) file format (this is the quickest). If you are writing in a loop it is also best to use the basic (low level) write VI's and not the express write vi. With he basic write file VI you are able to put the open file vi and the close file vi outside your loop, this saves a lot of time.
Please note that the SCXI 1600 module is deciding your maximum sampling rate.
I hope this helps,
Thank you for your quick reply. I wanted a file...DAQ Assistant does not start
When I log as a regular user, I can't start DAQ Assistant. But when
I'm log as the administrator, I can start the DAQ Assistant no
problem. It most be a permission problem in the registry or
something... I was wondering if their was a fix or a patch. Or I
must run it with administrator privilege?
Thank you for your help
This problem is most likely caused by a lack of permissions. The DAQ
Assistant is built from Measurement & Automation Explorer (MAX), and
the user needs permission to access MAX's files.
Complete the following steps to set up permission for the MAX\Data
1) Browse to the C:\Program Files\National Instruments directory.
2) Right-click the MAX folder and select Properties.
3) Click the Security tab, and click the Add button. Type in the user
name and click OK.
4) Give the user Read & Execute, List Folder Contents, and Read
5) Click Apply and then OK.
If the problem persists, try adding permissions for other folders in
the MAX directory.
If you have several different users and want all users to use the DAQ
Assistant, repeat the above steps but type everyone for the user name.
The above steps are written for Windows XP. For previous Windows
versions, the procedure will be very similar but may not be exactly
This proved to be the solution to my question. I got my sys admin to
change me to admin rights, and the problem was solved.
...How to use the DAQ Assistant?
I config its Acquistion Mode as continuous. I thought that it will run continuously without loop. But it is not the fact.
It must be placed in a loop while sometimes the error take place.
N sample mode also must be placed in a loop.
In this way, is there any difference between them?
Althrough DAQ assistants do the job of continous acquisition ( Yes, you have to place it in a while loop. the 'first call?' conditional check in daq assistant will ensure that all other functions ecxept the DAQmx read are...Missing DAQ Assistant
Hello friends, I have to handle analog input and output data with NI USB 6221. I have installed the Labview 8.5 version followed by my device drivers. Being a beginner I want to make use of the DAQ Assistant. However I do not find the much helpful DAQ Assistant anywhere in my Measurement I/O or in the Express VI blocks. Is anything wrong with my installation ? My driver CD reads DAQmx 8.5. Please send in your advice ASAP.jayaprakash<img src="file:///C:/DOCUME%7E1/jayapr/LOCALS%7E1/Temp/moz-screenshot.jpg" alt=""><img src="file:///C:/DOCUME%7E1/jayapr/LOCALS%7E1/Temp/moz-screenshot-1.jpg" alt="">
Thanks a lot Mr. Easterling, for your timely and valuable reply
to this beginner's message. I followed your advice, installed 8.6.1 and
successfully got the much useful DAQ Assistant. Being a beginner, I
have just now started using the DAQ Asst for simple tasks.
The crisis I am ...daq assistant in while loop
I have a very simple LabVIEW block diagram (attached). I'm getting readings from an LCR meter and some load and strain data through DAQ assistant. Both applications are in a while loop. I need all the readings to be at a rate of 10 Hz, so I've got a wait function with 100ms in the loop. Now, I'm not sure if I should set the daq assistant to one sample or continuous samples with 10 Hz rate? and if the latter, then what should I enter for the buffer size?
I forgot to mention that when I set the daq assistant to continuous sampling at 10 Hz and a buffer size of 1, there is an error that says:
"This task currently has an error...."
But it seems to be working alright when I run it. Is that ok?
...DAQ assistant encoder
Hardware: DAQcard PCI-6250.
I'm trying to look at a signal from a vibration sensor and relate it to the angle of a rotating shaft measured with an optical encoder.
I've used two DAQ assistants inside a while loop. Both of them work OK independently, but the encoder part only takes one measurement at the start of each loop (vi attached).
Does anybody know how I can synchronise its measurements to the vibration sensor?
All suggestions gratefully accepted... Jack
Your program is reading continuously from the vibration sensor at 1KHz while you are reading one sample on demand (software-timed sample) from the optical encoder. Therefore, they are out of sync.
You should modify the timing settings to match each over. Double-click the DAQ Assistant and configure the task parameters. What kind of sampling frequency is appropriate for the vibration sensor and the optical encoder in your application?
...Two DAQ Assistants
Hello I've got the following problem:I have a .vi with two DAQ-Assitants. The first one is a DAQ-Input who is collecting the data from several sensors. The second one is a DAQ-Output who should controll a pump. Now, separately, both of them work fine. The pump works as long as it should and I get all the needed information from the sensors. But as soon as I've got both assistants in the same .vi, the input-one doesn't work... So the pump is still doing their job, while I'm receiving just the default-values from the sensors... It seems like their waiting for something to finish...Any ideas what the problem is and how I could solve it?!?If it helps: - LabVIEW 8.5- DAQ USB6210- .vi is attachedThanks in advance for any help! reepicheep
Oh, I forgot to add that I've got just an Evaluation Software... But I don't think this should make a difference....
The problem might be because both the DAQ assistants will be trying to access the DAQ simulataneoulsy, try using the same DAQ assistant for both the operations...
I also thought that it could be something like that. But is it possible to use one DAQ-Assistant simultaneously as an input and as an output? And if yes, how?
Althought DAQ Assistants VI's are good to begin with, they are not handy when you want to perform multi-function operations like simultaneous output and input
Unlike what 'lordsat...DAQ trigger for labview
I do not know how to exactly use the TTL trigger and DAQ to program my data acquisition. Mainly I am reading voltage using DAQ.
Please see the attachment detailing my problem. The
first is about what I want to do and the second is how can I generate
TTL signal for my motor (I know how to do this part).
Message Edited by Dushyant on 08-06-2007 08:04 PM
PCset position compare mode.doc:
http://forums.ni.com/attachments/ni/170/263765/2/PCset position compare mode.doc
However, yesterday I figured out that TTL signal generating was not supported on my
motor controller from Newport.com: ESP -300 and it was supported
on ESP -6000. It was only mentioned at the end of Newport's manual n so, I missed it first time. Now,
I have to adopt to slow data acquisition and I have to do it
using software and of course, there may be some latency in program
execution; but, I want to minimize that. i.e. I want to avoid using for
loop or while loop.
I am using DAQ card PCI-MIO-16E-4.
The main code is "Fly_scan_St_Line_different_version.vi" and the other important subcode is "Motion_Update_Final"
The main code seems working almost fine. I am including all the subvis
and I want someone to help me on the frame no 1 (of 0,1,2) of stacked
The subvi "motion and update.vi"...DAQ Assistant Crashing
Im currently using LabView 8 Student Edition with a NI-9215 compact DAQ. After configuring the DAQ assistant the first time, if any other changes are made to it, LabView will crash. Are they any updates for LabView that address this problem?
Can I ask what version of the DAQmx Drivers that you are using as I have not come across a problem with LV 8 student and the 9215 before. It sounds more like a configuration issue. If you tried downloading the latest version of DAQmx this may help.
<a href="http://joule.ni.com/nidu/cds/view/p/id/965/lang/en" target="_blank">http://joule.ni.com/nidu/cds/view/p/id/965/lang/en</a>
Hope this is of some use
I am also having the same problem using LabView 8 Student Edition, NI DAQmx (V8.6), and a USB-6008. Once I configure the DAQ Assistant when building the VI file, I cannot go back into it to change any settings without LabView crashing while attempting to rebuild. It's rather annoying to have to delete the original DAQ Assistant and go through the entire config. process anytime I want to make a change!
I am downloading the latest version of DAQmx and am hopeful it will fix the problem. Did you ever find a solution to this problem?
Can you detail more about what happens when your LabVIEW crashes? Do you get an error message or an error log when you ope...DAQ assistant #2
I am begining to acquire signals with Labview 8.5.
Well, I have created a DAQ assistant to see my signal in a Wavegraph. ( I am acquiring an output analog voltage signal with sinosoidal form) . I can see a great signal when I look in the " Connection Diagram " of the DAQ assistant panel. it is just what I�m looking for and it move in a perfect real time when I change the signal. The question is how can I get the similar signal in a Wavegraph in the Block Diagram?I have tried it changing the parameters like rate, amplitude... but I have only got changing straight lines and these are very diferent of the sinosoidal form of the connection diagram.
I�m not very good with Labview but anybody knows some trick to watch in the block diagram the good signals of the connection diagram?
Thank you very much!!
...Need labVIEW assistance
I need to create a labview program which will automate the cleaning process of an atmospheric chamber. I have no idea where to start. If some kind soul out there would be willing to give me his/her email address incase i come across some problems i would greatly appreciate it.After an experiment is completed an elevator lowers the chamber and evacuates the emissions tested, but the pressure inside the bag (chamber) must be constant at all times. If the pressure is too high then the bag will tear, and if the pressure is too low then the bag will deform. The cleaning process ionvolves lowereing the bag and keeping it at a constant pressure. When the bag is completely lowered, the cleaning process begins. This involves filtering the bag with purified air and then evacuating it and repeating the precess 5 more times.HELP!
It is highly unlikely that you will get folks to give you their email address, what with the prevalence of SPAM. You might, however, get a number of business cards from folks willing to do the work for you. :smileywink:With a situation such as this you should first model the system, and develop an overall operational diagram of the system. Write down what the input conditions are to the various components, how the components interact, and what causes a component to behave a certain way. What kind of requirements do you have? Which requirements are must-have, which are kind-of-nice to have, and which are gravy? A state machine will...DAQ assistant trouble
I have my DAQ assitant reading two channels simultaneously (both are voltage reading in the order of milivolts). When I plot the data from the assistant, both signal are clearly shown and when each channel is triggered I can see teh voltage go up. I set up a trigger so it starts a loop.
This trigger is connected directly to the DAQ assistant data but it only works for one of the channels. What going on?? Please help
Hey kruhun, Are you using a hardware trigger or a software trigger? Is the trigger starting the acquisition? It might be best if you just posted a simplified version of your VI that shows the issue.Regards,
...daq assistant #3
Hi, I recently installed Labview version 8.5. I installed the data acquisition cds aswell, but there is no daq assistant icon, instead there is a blank space where it should be. I would like to know how to access and to create the icon on the functions panel.Regards,Mark
I would suggest you reinstall the DAQmx drivers. You can get the most recent version from our website at: <a href="http://joule.ni.com/nidu/cds/fn/p/sn/n17:hardwareDriver,n23:3478/sb/navsRel/lang/en?q=DAQmx" target="_blank">http://joule.ni.com/nidu/cds/fn/p/sn/n17:hardwareDriver,n23:3478/sb/navsRel/lang/en?q=DAQmx</a>
I hope this helps,
hi, I tried re-installing the drivers but theres still no daq assistant on the palette
Acquisition palette relies upon two installations: the LabVIEW
installation and the DAQ driver installation. When the NI-DAQ drivers
are installed, the installer will automatically detect the versions of
LabVIEW present on the computer. Most often, the DAQ support for these
versions of LabVIEW are then installed. Unfortunately, this means that
if you upgrade to a newer version of LabVIEW you will need to add DAQ
support for your newer version of LabVIEW by modifying/reinstalling
your DAQ drivers.
Steps to ensure driver VIs appear in LabVIEW:
that all development environments being used (LabVIEW, CVI, etc.) have
been installed before the device driver. Installing LabVIEW after a
driver will not update the functions pale...Cannot find DAQ Assistant drivers..
I'm trying to run a program written (I believe) on 7.1 however when trying to run the program I have a series of missing VI prompts. I have been able to locate most of these on the old hard disk and have pointed to them, however I cannot find the Configure DAQmx Assistant.vi required for the VIs in the program even though I have installed NI-DAQmx 7.2. I don't believe the other program was written with anything other than these resources so I'm a little confused. Was a later NI-DAQmx driver possible installed?
If u have confidence that you have installed the necessites, please check out the following location in ur system,
C:\Program Files\National Instruments\LabVIEW 8.5\vi.lib\express\DAQmx\DAQAssistantConfig
There one llb file named configVIs.llb will be there within which the required Configure DAQmx Assistant.vi you have asked was resided.
Hope this helps,