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
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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

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Attachments:
tristate_test.vi ‏11 KB

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Attachments:
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Solved!
Go to Solution.

I had a very similar approach, so here's another example in case it helps. This example loops through all files in a specified directory, and if the file is a TDMS file, it loads the first channel in the file and calculates the maximum value.
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Solved!
Go to Solution.
Attachments:
multi_chan_errr.JPG ‏42 KB
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channel_name.JPG ‏69 KB

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Solved!
Go to Solution.

As far as I know you can treat it as a string. Just concatenate. (Note the forward slash)
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Error Code -50150 from DAQmx Create Channel (AI-Voltage-Basic).vi

I have an executable, built from Labview 7.1 VI's. All it is doing is reading 6 voltages back from a 6008 USB-DAQ, and reporting the results back. Occasionally, it is throwing an Error -50150 from DAQmx Create Channel (AI-Voltage-Basic).vi. The full error message is:
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DAQmx Create Channel (AI-Voltage-Basic).vi<append>
<B>Task Name: </B>_unnamedTask<0>
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Hi fellas,
I have a really similar problem to the one Neilelph had, but I can´t see how to solve it from your answers. I attached a picture of my main .VI.
It´s basically a photodiode measurment system working as follows:
1. First the moving stages for the system get ready (X-Y moving stages for the Photodiode and Z stage for the Laser). That´s the CONFIG subVI in the left.
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Maybe it would be useful to mention that, sometimes, there is no error and I have some DC Output Voltage value, for random Z potitions, but since the first error message, that barely happens. The output is almost always 0.
Sorry for my writting skills in English. I hope you can understand my situation.
Thank you in advance.
Kind regards,
frilance.
Attachments:
Diagram.JPG ‏83 KB

Editing channels in a task using DAQmx in Labview

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Pooja,
1.) The ability to create, what I assume is multiple global channels, all referencing the same physical channel, is not a bug.
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Extract single channel from DAQmx Task

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