How to sync and/or trigger NI-DAQmx devices in LabView

Question

I am using LabView 2009 with a cDAQ-9174 chassis that includes a NI 9263 analog out device and a NI 9222 analog input device. I've learned from the examples that I can sync the devices to the same sample rate. But I am looking to sync the devices such that the exact moment I start acquiring input data on a 9222 channel, the 9263 starts generating an output. Secondly, I am interested to know when using just this equipment, is there a way to very accurately trigger one device off the other with some delay. So in summary I am interested in two behaviors:
1) Synchronize a 9263 output channel to a 9222 input channel, such that the start of a 9222 analog input measurement triggers a 9263 analog waveform output. and,
2) Have the 9263's analog output start for example EXACTLY 100 samples (provided sample rates are synced) after the 9222 starts collecting data. In other words, a delayed trigger.
I imagine this is preferably done in hardware such that no software delays occur. Is this possible using these devices? Or do I need some external clocking mechanism?
Thank you!
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Answer 1

Hi tzoom84,
Going back to your original questions,
To do 1) and 2), I don't think you need to use counters.
The shipping example LabVIEW 2010\examples\DAQmx\Synchronization\Multi-Function.llb\Multi-Function-Synch AI-AO.vi is probably a good starting point for 1). (Possible problem: if you're using multiple AI timing engines at the same time, this example's assumption that the AI task has "ai/StartTrigger" is not valid. If this turns out to be an issue, you may need to replace Get Terminal Name With Device Prefix.vi with the DAQmx Trigger >> Start.Term property and add a call to reserve the task.)
For 2), add the DAQmx Trigger >> Start.Delay and DAQmx Trigger >> Start.DelayUnits properties to the AO task:
If you really do need to use counters, you can do so without the NI 9401 by using cDAQ1/_ctr0 through cDAQ1/_ctr3, which are internal channels: How do I Access Internal Channels on any DAQmx Device?
Brad
Brad Keryan
NI R&D