Output Separate Waveforms on PXI-4110

[John Lipor]

I am using a pxi-8186 controller with 2 pxi-4110 power supplies and need to be able to set each channel (6 in total) separately of the two supplies to output either a dc voltage or a sine wave with some noise.  I can get any one channel to do this at a time, but when I try to put 3 (or even 2) together I have problems.  I'm really not sure how to go about this because it doesn't seem like there's any good way.  I've attached an llb with my files in it.  The lowest level vi (sine wave with noise) makes the sine wave with noise, then next one up (one channel power) lets you choose either a sine wave or a dc voltage and output it.  The one that I'm having trouble with is the One Slot Power.vi, where I'm trying to configure all 3 channels.  What happens when I run this is the first channel outputs fine, but the other two do nothing.  When I stop Ch. 0, Ch. 1 will output.  The same thing happens for Ch. 2 when I stop Ch. 1.  Any advice on how I can run all 3 of these sub-vi's in parallel (if this is even possible) would be greatly appreciated.  Thanks in advance.

John Lipor

[Mark_E · Accepted solution]

Hi John,

I didn’t dig into your code very far, but I noticed that the calls to the three channels are done sequentially instead of in parallel. That’s probably why the outputs are happening sequentially.

I took the time to modify an example program to generate voltage on two output channels in parallel. This is merely an example of how you would create parallel tasks, but should give you a good idea of the structure needed to output voltages in parallel. You would expand it to the third channel and add your noise, etc.

You may need the NI-DCPower 1.2 driver to run this.

I hope this helps!

[John Lipor]

This helped a ton, I didn't have that driver which I think was part of the issue as well.  Thanks for your help.

John