Normally the way I acquire sample from more than one channel on a cDAQ system is like this:
1, I create virtual channels for my AIs in MAX
2, in LabVIEW I use channel constants and merging them using comma as a separator (eg. with the concatenate string node).
3, the I configure the sample clock using the comma separted channels as an input
4, start the task
5, acquire samples
6, stop and clear the task
This worked just fine so far as I acquired samples from my cDAQ modules with the same speed and all of them were simple analog inputs. But I have to implement a strain gage measurement (NI 9237) now and I'd like to use the bridge offset nulling calibration VI to get rid of the offset I have. That complicates my structure.
It seems the VI I have created runs just fine but I am wondering if this is a legit solution as I used the sample clock twice. (the VI uses simulated channels for now)
Attached the VI (LV2012) and its block diagram image as well.
I have failed to realize that the offset nulling VI has another input called "skip unsupported channels". This is false by default, but setting it true resolves the problem without changing my structure at all.