Selected physical channels to array

I would like that after select several channels of differents devices (with DAQmx Physical Channel component), this selected channels will be put in the array.
I look for forum but I didn't find anything.
If somebody already tried to do this, please send me suggestion.
Thx for all
Look in the attached picture.
Leonardo de S. Cavadas
Maintenance Engineer and Inspection - Bureau Veritas do Brasil
Engineer Metallurgist with emphasis in Advanced Materials
Technologist in Computer Science
Attachments:
physicalchannel.JPG ‏39 KB

Chris,
Now you will understand what I want. I didn't expressed well. Look for attached VI
Leonardo de S. Cavadas
Maintenance Engineer and Inspection - Bureau Veritas do Brasil
Engineer Metallurgist with emphasis in Advanced Materials
Technologist in Computer Science
Attachments:
physicaltoarray.vi ‏11 KB

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I figured it out from 372251a.PDF
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Thank you for your feedback.
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Thanks for your reply Dennis, I see what you mean, unfortunately that doesn't solve my problem so I'm missing something else. I've attached my VIs. I expected that the output from the unflattenstring block would be an array of either the channel references or the names I had given them, and that therefore the "array size" in the 4th pane would be "9" (equal to the number of channels). Instead the output is a an "unnamed task#(some number)" when I look at it with a probe. Perhaps I'm misunderstanding how the task naming works?
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Analog SW Trigger_v3.vi ‏33 KB
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Physical channel

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Attachments:
b.vi ‏25 KB

If you have configured everything correctly in Measurment and Automation Explorer you should be able to right click and create constant on the AI Config. This will then give you an array of I/O constants which you will be able to select the configured information form MAX for each channel. Hope this helps.
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Maybe I'm trying to pound a square peg into a round hole, so please let me know if I'm abusing LV, but ...
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Hi Keith,
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Message Edited by MikeS81 on 07-25-2008 06:46 AM
Attachments:
Unbenannt1.PNG ‏6 KB

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Can anybody tell me that if a DAQmx Control gets value from a configuration file( .ini file ) and the value is invalid (does not exist in the available physical channels list) than how I can be programatically intimated. I couldn't find any property node of DAQmx Physical channel Control which tells about that the current value feeded to the control is invalid.

Thanks Alan, I have got a better soloution from you in another thread launched by me with title "How to get "Browse list of any DAQmx control in array form". In which u suggested of using DAQmx 8.0, which I have downloaded and used the property node DAQmx-Device>>DO.Lines to get an array of all Physical channels(DO category) of all devices. The value taken from that configuration file is searched in Physical channels array and if no match found than the value is invalid.

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Hello all,
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I know that by right-clicking on the physical channels control, I can filter it but I can't manage to figure it out how to filter by specifiying a device. Maybe by using property nodes...I don't know.
If somebody has a solution, that would be much appreciated.
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You can configure IO Name Filtering by choosing the following option in the context menu:
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Insert element in selected column of 2d array

Hello
How to insert value in selected column of an array
In my program i am reading the CAN data from channels using
CAN read Channel API, the recent data read from the CAN channels
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i attached my VI
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Attachments:
err2.zip ‏89 KB

For 2D arrays, you must insert entire rows or columns at one time. You cannot insert just one element. Why? Lets say for example you have a 2 x 3 array (2 rows with 3 columns). If you insert an element in row 3 (a new row) column 1, what goes into columns 2 and 3? You just messed up the integrity of the array, and Labview doesn't allow that. What you need to do is gather data for all columns in the new row and insert the entire row. The Insert Into Array function is used with the row number wired to Row Index and nothing wired to column index. You can gather all your data, build a 1D array and insert that array into a new row in the 2D array.
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Extract device from physical channel

As always I want to do something absolutely trivial and am running into all sorts of issues
I define (through a control) a physical channel that I want to take data on. I want to be able to programmatically reset the device the channel is on. i.e. i don't want someone to have to open up the code and change the device on the reset vi if necessary. Even if there is only one device physically connected, you can’t guarantee the device will be Dev1, because Labview keeps a history of devices that have been plugged in. The obvious solution – extract the device name from the physical channel control which contains the channel(s) you have selcted. Can I find a trivial way to do it, NO! There is a property node called device but it does not (despite its name) return the device you have selected along with the physical channel. There are convoluted ways of doing this, but i'm hoping there is some easy way. Suggestions
Solved!
Go to Solution.

I think this might be the "trivial" way you're looking for: some string pattern matching and a simple
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Hi,
I am new to Labview but I managed to create a new analogue voltage input task in Measurement and Automation Explorer. I am using DAQmx create virtual channel VI but I am getting an error message saying that "required input physical channel is not wired". Any idea why I am getting this error message. Also what is the difference between using DAQmx Assistant and using VI's like DAQmx create virtual channel, DAQmx timing etc.Any help is appreciated.
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Attachments:
error2.JPG ‏171 KB

The first VI 'Create Virtual Cannel' has an input called physical channel. This needs an input. Right click on the terminal and select Create>Constant. Then you can select the channel (something like Dev1/ai0).
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Hi people,
I need to associate an input channel to a certain output channel. Of course, that led me to the idea of a hash table and as Labview doesn;t have such a structure defined, I thought of using a case structure.
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Labview seems to index them according to the order they are introduced in the Physical channel, so one can manipulate them by extracting from the complex signal the array indexed 0, indexed 1, ...respectively.
My purpose in the end , though, is to associate Dev1/ai0, Dev1/ai1(and not the channel's index)... with some certain numbers into a somewhat hastable.
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Hi Mike,
Thank you very much for the solution. Yes, this is the right way.
I'd come up with another complication.
What if the name of the channel is not available-can I first extract it from the index of the individual signal that I extracted from the complex one?
I made some comments in the picture , it's part of my actual application. Could I have your opinion on that? I placed an icon if the DAQmx channel propery - is this an answer to the question I posed? I cannot link some things in my reasoning, maybe you can help.
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Attachments:
channel name.JPG ‏153 KB

PXI has no physical channels!!! Please help!!!

Hello.
While using DAQ Assistant, when the window of selecting a physical channel appears, no physical channels appear. I try to use NI-5122 and I think everything is well configured in MAX (PXI-1002, External PC, MXI-3).
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Is PXI-5122 supported by NI-DAQmx???
I also have installed a PCI-5102, but as it works with Traditional NI-DAQ it shouldn't appear, should it??

Hi Shawnyap, I have no clue what version of LabVIEW you have, so I'll send my 7.1 example.
However, if your examples are corrupted, I'm going to highly recommend you upgrading to the latest driver at the link below and using the examples that come there. If those are corrupted, there's a good chance something else is broken too.
http://digital.ni.com/softlib.nsf/webcategories/85256410006C055586256BE600709528?opendocument&node=1...
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niScope EX Configured Acquisition.vi ‏208 KB

Selected physical channels to array

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