cDAQ-9174 Max Number of Modules bug?

[mcduff]

This error occurs in NI MAX, version 16, and LabVIEW 2015.

I have four c-modules plugged into the cDAQ-9171, all of the modules are analog voltage in, for example, the 9223, 9234, 9239, and 9244 modules.

Here are the steps to recreate the error:

1. I open MAX and see all of the modules.
2. I click on the first module and select Test Panel and Continuous acquisition.
3. I click on the second module and select Test Panel and Continuous acquisition.
4. I click on the third module and select Test Panel and Continuous acquisition.
5. When I click on the fourth module and select Test Panel and Continuous acquisition, I get Error -200022, resource requested by this task reserved by a different task.

It does not matter what order I click on the modules, whenever I get to the fourth one I get this error.

So does the cDAQ-9171 only allow 3 analog input modules? I really do not understand this error. I have tried unplugging modules, using different modules, etc. What am I missing?

Cheers,

mcduff

[Alexander_Sobolev · Accepted solution]

Yes, according to datasheet you have 3 timing engines = 3 tasks with different frequency.

You can join 2 tasks for 2 modules into 1 task and sample at the same frequency.

[mcduff]

Thanks for clearing that up. One last question, where on the data sheet does it state this?

cheers,

mcduff

EDIT: I found it, I was looking in the manual before, not the data sheet.

Thanks again.

[Alexander_Sobolev]

It is not in 9174 specifications (http://www.ni.com/pdf/manuals/374045a.pdf)! 

It is in 917x overview, page 1:

http://www.ni.com/datasheet/pdf/en/ds-178

and in 9174 manual, page 27 Analog input

http://www.ni.com/pdf/manuals/372838e.pdf

[mcduff]

Thanks again. I need to look in the right spot next time.

Cheers,

mcduff