Get DAQmx tasks parameters

I've created in MAX 4.0 some DAQmx tasks to control diferent digital outputs bits (I attach a picture of it). I have to develop a TestStand step type with LabVIEW 7.1 in edit mode able to select any of this predefined tasks and show the bits correspondence (following the picture it would be for example "DigitaOut4 -> Dev1/por0/line2"). Is there some method to get all those parameters? Does somebody has a small example? Thanks in advance.
Mackemann
Attachments:
MAX DAQmx Tasks.JPG ‏62 KB

You can get all of this information from DAQmx property nodes. I wrote a quick example and there are probably more on either the LabVIEW or DAQ boards.
Message Edited by Dennis Knutson on 03-30-200602:56 PM
Attachments:
DAQmx Properties.JPG ‏30 KB

Similar Messages

Why can I not use the channel name, which is obtained from the function of DAQmx Task, as the input of the channel name for the function of Get Channel Information of DAQ?

Why can I not use the channel name, which is obtained from the function of DAQmx Task, as the input of the channel name for the function of Get Channel Information of DAQ?

Not a lot of details here, but my guess is this isn't working for you because you are wiring in the task to the Active Channels Property and not the actual Channel Name. I have attatched a screenshot of what I believe you are trying to do. The Task has 2 channels in it, so I need to index off one of the channels and wire it into the active channels input of the Channel Property node. Then I can read information about that channel
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channel_name.JPG ‏69 KB

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Solved!
Go to Solution.

Thanks Mike,
I attached the relevant code pieces. Generally, it is based on the example on NI-DAQ\Examples\DotNET4.0\Synchronization\Multi-Device\AIContAcquisition\cs.
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Regards,
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Attachments:
SynTask.zip ‏9 KB

Full information about DAQmx Task Name - How get?

Labview 7.1 (information required for solve problem)
I put in my application a DAQmx Task Name for fast configuration but i want put all information about task in a txt or spreadsheet file. But in Labview 7.1 haven't VIs like (http://zone.ni.com/devzone/cda/tut/p/id/3079):
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Maintenance Engineer and Inspection - Bureau Veritas do Brasil
Engineer Metallurgist with emphasis in Advanced Materials
Technologist in Computer Science

Sorry about that, I haven't checked if they were made only for LV 8 and later. Attached is a zip file with all the VIs converted to the version 7.1.
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Best Regards
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Attachments:
DAQmxTaskInfoQuery.zip ‏586 KB

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-Kevin P.
Attachments:
DI Action Engine.vi ‏75 KB

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Solved!
Go to Solution.
Attachments:
Freq Set Up.jpg ‏2993 KB

So I would select new in "Custom Scaling"
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-200428 - Modifying a channel in a predefined DAQmx task

I was pretty sure I had done this before, but maybe not. I have a predefined task setup in MAX spanning 3 different analog input modules on a cDAQ chasssis.
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Any clues?
Solved!
Go to Solution.

Hey Mike,
Can you please try it like illustrated in the attached jpg.
Christian
Attachments:
hint.jpg ‏36 KB

Examples for good programming practice with multiple DAQmx tasks

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Also, say I have a state machine that has a configure, idle, and logging states. I need to set the initial values of the encoders during configuration, and keep up with their changes while in the idle state so I have appropriate starting values when entering the logging state. Can anyone point to an example that shows how this might be accomplished?
Thanks

I'm very familiar with AE's/Functional Globals - but I have struggled in the past with handling multiple DAQmx tasks - particularly when you're using multiple devices and using different types of measurements which require seperate tasks/handling (e.g. such as thermocouples which require extra compensation).
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I think in hindsight (and without too much thought now) it looks like a good case for Object Oriented LabVIEW - with a base DAQmx class (initialise, configure, start, acquire, stop, close etc.) and then child classes for each type of measurement (with one task associated with each - and private data unique to that specific class). You then hold an array of objects (one for each task) and iterate through each one with dynamic despatch to get the data.
I don't know your particular experience level of using LabVIEW (and as such, OO may not be appropriate) - but as a wider discussion of 'best practice' it seems like an appropriate method I would use going forward.
Certified LabVIEW Architect, Certified TestStand Developer
NI Days (and A&DF): 2010, 2011, 2013, 2014
NI Week: 2012, 2014
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Extract single channel from DAQmx Task

Hello,
I have created a DAQmx output task, which contains two channels. Is it possible to extract individual virtual channels from the task to be processed by two parallel processes? I have tried bringing out the Channels Property using a Task Property Node, but I then get the error that the channel is not part of an active task (see attached snippet)
Could anyone advise on a better approach, or how to acheive this functionality - if it is possible?
Regards
Dave
Solved!
Go to Solution.
Attachments:
split out channels from DAQmx task.png ‏34 KB

Sorry, that VI does not make much sense. You have to use a single DAQmx Write for both channels and for 1 Sample mode, you simply have to build an array of the signals as shown below.
Attachments:
two channel write.png ‏12 KB

DAQmx tasks

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Hello RedRider. Thank you for contacting National Instruments. You cannot do more than one analog input task at a time. There aren't enough resources on the board to do this, you will have to do them one at a time. You can incorporate more than one analog input into a task, but this won't work with your situation. If you would like to make a product suggestion to do this in the future, click Product Suggestion. Hope this helps. Have a great day!
Marni S.
National Instruments

Display all DAQmx Task Names in Listbox

I have a DAQmx Task Name control on my VI that allows the user to select from a list of existing Tasks created in MAX.
I would prefer this list of "available tasks" to be displayed (and eventually have one task selected) using a listbox.
For the life of me I can't figure out how to get the DAQmx Tasks into a listbox.
Anyone have any advice?
Solved!
Go to Solution.

Where are you getting the vaiants from? It should be an array of tasks (a DAQmx task is a data type). Just wire that array straight into the ItemNames propty for your listbox.
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Attachments:
DAQmx Tasks to Listbox.png ‏13 KB

Storing DAQmx Task in a Functional Global variable

Happy New Year to everyone!
I got a nice little question hoping some of you might be able to help me....
After initializing an starting a DAQmx task (V7.5), I wanted to store the task out reference in a functional global variable, but it seems, it didn't work.
Everytime I tried to call a DAQmx VI with the opened reference, I get an error, the task would not be existing....
I already made a workaround, so everything works fine. I'm just curious what I made wrong....
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Oli
Programming languages don't create bad code, programmers create bad code....

Helo Oli,
Normally, you should not have a problem storing a task reference in a variable. However, the vi that created the task has to stay in memory for it to work. Closing the vi will result in the destruction of all created hadles -
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Regards
Ingo Schumacher
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Get DAQmx tasks parameters

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