Capture AO with AI and synchronise to TDMS

[polpetta05]

How do I save the output that I write to a AO channel, along with some input from a different AI channel, to the same TDMS file so that they are syncronised? 

Summary of what I want to do:

- I have some signal that I want to write to a AO channel. Call it x.

- I have some signal I want to capture from a AI channel. Call it y.

- I want to save x and y to a TDMS file so that x and y are syncronised.

The way I have been doing it in the past is to feed the output from x back into a new AI input and then capture that. This wastes an AI channel, and I'm sure there's a better way to do it. 

[Sean_N]

For your analog input virtual channel, you can select your AO channel vs ground as and AI channel.  You will have to right click your physical channel control/constant and click I/O Name Filtering... Then make sure you select internal channels.  Then you can just use channel expansion to select both your AI channel and the ao0_vs_gnd channel.  You will still need to use a setup similar to the Multi-function Synch AI-AO example to physically synchronize the AI and AO, but this way you won't waste a channel.  Just to verify, I created an AI task and selected all physical channels, as well as ao0_vs_gnd and I didn't get a reserved error.  You will obviously need to change your DAQmx Read to read multiple channels and then just write to the TDMS from the the Read VI.

Thanks,

Sean