Case structure and DAQmx not selecting correct input channel

[kashi13]

I'm trying to set up three modes with the case structure seen in the attatched file. Each mode has 1 set of differential analog input signals and then one NRSE analog input channel as well. For some reason I am unable to get all three modes to work as they should. In the end I want the user to be able to pick between the three pre-determined modes. Many times it gives me error number 200489 or will not update my graphs/charts at all. 

I am a new user to Labview so any pointers would be greatly appreciated!

[crossrulz · Accepted solution]

You do realize you are using multiple channels with that differential measurement, right?  You are setting up 2 (3 in the option 1) channels as differential.  The differential channel AI0 will use AI0 as the + and AI8 as the -.  If you read the manual on the DAQ card, it will become more evident.

But the cause of your error is in mode 1.  You are defining your differential channels AI0 THROUGH AI2.  So AI1 is already used.  There's your error.

[kashi13]

Thanks crossrulz for the help! That totally makes sense!

You wouldn't happen to know how to specifiy the file output type on the 'Export Waveforms to Spreadsheet File.vi' would you? For example when I run this .vi it saves as a generic file, when I would like it to be saved as a .csv or a .xls file. 

Or do you know how to display more elements of a 1D array in the interface? Like in a matrix rather than just the first row of elements?

Thanks in advance for the help!!

[crossrulz]

The Save Waveforms to File VI saves the data in a text file with whatever delimiter you tell it.  Therefore, you can make it a CSV .  XLS files are a little more interesting.

From what I can gather, what you really want is probably something like the attached.