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Please help me understand what is happening in this piece of code

I am working on some code we got from France and I am not understanding what is actually going on in this.  We are taking the Max DAQmx tasks and changing it to programmatically create them due to some issues we are having.  I just don't understand what is happening here and how I can programmatically do this.   I have never experienced using the DAQmx Flatten Channel String.vi  What is it doing in this situation?  How do I create this programmatically?  TIA

 

 

French code.png 

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Message 1 of 6
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DAQmx flatten string is just a fancy way to convert the array into comma separated string.

Santhosh
Soliton Technologies

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Hi Sam,

 


@801Sam wrote:

I have never experienced using the DAQmx Flatten Channel String.vi  What is it doing in this situation?  How do I create this programmatically?


It flattens te given list/array of channels into a string containing all channels in expected formatting - as described in the help for this function!

The context help says:

Converts an array of physical or virtual channel names to a comma-delimited list of names. You can use this VI to convert an array of channel names to a single string prior to using the DAQmx Create Virtual Channel  VI or the DAQmx Create Task VI.

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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Yes, Thank you.  I read the help.  Does doing this combine the two channels?  I need to figure out how to do this through programming.  I tried creating the two channels then flattening them.  I got this error.  Why I am not trying to use the MAX Tasks is the pc I have this code running on has only the executable and for some reason tasks are not working on it.  So, I found online where it said some MAX tasks have issues.  

 

Possible reason(s):

Specified virtual channel or task is invalid.
If you are attempting to add channels to a task, create a virtual channel using the DAQ Assistant or DAQmx Create Virtual Channel, and then add the virtual channel to the task.
If you are attempting to reference a LabVIEW NXG project task from a LabVIEW NXG VI, any of the following may resolve the error:
1. Ensure the task name is correct.
2. Use a DAQmx Task constant to reference the task from the VI's diagram.
3. Configure the task's owning Application or Library to export or always include the task.

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Message 4 of 6
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Hi Sam,

 


@801Sam wrote:

Does doing this combine the two channels?  I need to figure out how to do this through programming.  I tried creating the two channels then flattening them. 


When you want to add two channels to a DAQmx task you can call CreateVirtualChannel twice one after the other and wire the DAQmx task from first to second…

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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Message 5 of 6
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Ok, I got it.  The problem I was having was I forgot to change channel name for the second create.  Thank you for your help

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