NI-MyRIO Analog Inputs

[trouinky]

Greetings,

I'm just getting the myRIO up and running, and I'm sort of disappointed that the +/- analog inputs are differential only. Is there any low level way to use these channels differently, or at least each as single-ended? Pseudo-differential, perhaps? I'm going to have to resort to using the line-level audio inputs to measure single ended inputs and make sure the input level is lower than whatever the max voltage is for that (1.7 volts or something).

Any users out there care to comment?

I know the other inputs are single ended, but only 0-5V. Bummer.

Thanks in advance.

TR

[nikale]

Hi,

The Analog Input/Output can be wired single-ended for the myRIO-1950 with AGND as the reference. I've attached two links below.

http://www.ni.com/pdf/manuals/376099a.pdf

http://www.ni.com/white-paper/3344/en/

I'm not quite sure if this is what you meant, but I'm not aware of any low level way to manipulate the myRIO. I hope this helps!

Kale W.
Applications Engineer
National Instruments

[trouinky]

I grounded the 0- and 1- inputs of the two differential channels and had no problem measuring  single ended voltages going into 0+ and 1+. I was just expecting to be able to configure the four inputs to be four single-ended inputs like I normally can do on all other NI DAQ analog hardware. The project I'm working on needs four measurments (all +/- voltages), so I was hoping the two +/- 10 channels were reconfigurable to four, like I'm used to. I'm just going to have to be creative and use the audio inputs as well.

[charlesy]

Be aware that the audio inputs are passively AC-coupled, so you may want to buffer your signals to avoid output impedance-related frequency roll off.

[trouinky]

Didn't even consider this. Thanks for the tip.