How do I set the analog input channel?

[bradle95]

I am trying to read several analog inputs. No matter what number channel I assign to the vi, it reads the same voltage. I created a new analog input channel in MAX, but when I went back to the block diagram and tried to browse the channels there were none to choose from. How do I set analog input channels?

[Ram2003]

First step is to make sure that you read all analog channels in MAX correctly? Click test panels button in MAX to test individual channels. If channels are reading values properly, you can use DAQ assistant express VIs and select different channels.

[bradle95]

I did run the test panels, and they were working properly, is there a way that I can avoid using virtual channels, and just use the physical channels? I believe that I have already tried using the DAQ assistant and it did not work properly, so if there was a way that I could simply assign the physical channel to be read, I would be home free.

[Russell]

Hello,

Yes, you can just read the physical channel in your LabVIEW program. In fact, most of the shipping example programs are written this way. For example, you might look at "Cont Acq&Graph Voltage-Int Clk.vi" With DAQmx, you use the DAQmx Create Channel VI to configure a task for a physical channel. The terminology has changed somewhat though. In DAQmx, this is still called a virtual channel although called a "local virtual channel." Creating a virtual channel in MAX where it can be saved for later is called a "global virtual channel." When using the DAQ Assistant, you're actually creating the whole task which includes timing and/or triggering configuration as well.

I hope this helps.

-Russell
Applications Engineer
National Inst
ruments
http://www.ni.com/support