Read specific channels of PCI 6014

[Cindy1]

Hello, I have a PCI 6014 board which could have 16 Analog Inputs. Two of my signals are connected to ai3 and ai7, repectively. I am using DAQmx in Visual C++ (NO Measurement Studio). I create a task, create two analog input channels (for ai3 and ai7), start the task, and do acquisition from both channels. However, sometimes, I need to acquire the signal from ai7 only. How can I acquire the signal from ai7 only instead of acquiring all the channels I have created?. I checked the help but still did not know to do it.

Thanks.

Cindy

[Brooks_C]

Hello Cindy,

Once you've started a task the only way to actually remove a channel is to stop the task and recreate the task with fewer channels.  This would cause a delay between acquiring both channels and then starting to acquire only the one you want.  That being said, you could easily add a case statement to just ignore the data you receive from the channel you want to "remove."  You would still be acquiring samples from the other channels in hardware, but you would just remove the extra data in software.  If this isn't a satisfactory solution it would be helpful if you can provide a more specific description of what you want to do and why you want to remove these channels.

I hope this helps!

Cheers,

[Cindy1]

Brooks_C,

Thanks for the response. As you said, I will just discard the useless data from another channel.

Cindy