Daq with multiple modules

[jbladh]

I have an NI-9209 for thermocouple readings, a NI-9214 for voltage readings, and two cDAQ-9171 ports for interfacing with my computer via two USB cables. I can take readings from the 9209 or the 9214 individually using DAQ Assistant. But when I set up the DAQ assistant with channels from both devices I get error-201483. I am new to all this but the error makes it sound like I am not using the right equipment to take readings from two different devises in one VI, but I don't know. Is there a way for me to get temperature and voltage readings from both devices at the same time in the same VI?

Perhaps I could use DAQmx to make it so the VI read one devise at a time? But I don't know enough about DAQmx to write that code. 

Preview attachment Daq with multiple modules 2.PNG

Preview attachment Daq with multiple modules 1.PNG

Daq with multiple modules 1.PNG

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Daq with multiple modules 2.PNG

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[RavensFan]

You've got issues with your links or attachments.  They are pointing to a G-mail account.

You need to use the Browse button to upload your attachments.  Don't point to images with URL's that we can't access.

A cDAQ-9171 is a single module device.  Are you saying you have a 9209 module in one 9171, and a 9214 in another 9171?

Of course you can't put both modules in the same task when they belong to two different devices.

Just create two different tasks!  Run them in parallel in the same while loop.

[jbladh]

Yes, I have two cDAQ-9171 devises. They are both plugged into my computer via two USB cables, and one has the 9209 while the other has the 9214. 

What do you mean when you say "in the same task"? Are you referring to the DAQ Assistant? 

And, what do you mean when you say "just create two different tasks"? do you mean to create two different DAQ assistants? One for the 9209 and the other for the 9214?

See the attached, I think I fixed the problem with my images. 

[GerdW]

Hi jbladh,

learn those DAQmx basics!

[RavensFan]

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@jbladh wrote:

Yes, I have two cDAQ-9171 devises. They are both plugged into my computer via two USB cables, and one has the 9209 while the other has the 9214. 

What do you mean when you say "in the same task"? Are you referring to the DAQ Assistant? 

And, what do you mean when you say "just create two different tasks"? do you mean to create two different DAQ assistants? One for the 9209 and the other for the 9214?

See the attached, I think I fixed the problem with my images. 

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Yes of course.  A  DAQ Assistant is one task.  So create 2 DAQ Assistants.  Or better yet, follow Gerd's advice and learn to use real DAQmx functions.

[jbladh]

Thanks. Creating 2 Daq assistants worked. I tried that before and it didn't work. But I realized this time that the two Daq assistants were taking samples at different rates. I adjusted the rate so they were both taking samples at the fastest rate of the slowest devise and that did the trick.