synchronization between DAQmx and AWG

[labmaster]

I would like to get a concept of (starting and measuring) sync between DAQmx (AI and AO, typically 1MHz sampling rate) and AWG(PXI-5421, >10MHz).

I found a typical example in NI example finder but, I am very wondering if this is correct in my application.

In script mode, I want to give a soft trigger to change a generating waveform during the measurement.

My goal is to take data correctly for a definite time in each waveform.

If there must be delay in AWG in changing a waveform, I have to consider in DAQmx AI and AO. 

When I applied the trigger, conceptually, it is possible to be a delay between DAQmx and AWG.

(For your reference, I attached the delay, arrow in blue color, by adopting from NI tutorial.)

The tutorial present there should be a trigger within a cycle shematically. 

How can I get or give a real trigger signal when a frequency is changed?

labmaster. 

[mr_]

Hello labaster--

It sounds like you there might be a couple of options.  I'll link you to some documentation that should hopefully help you get started.  The first option is utilizing Marker Events.  In this case, there is a nice tutorial that explains its use. You may want to open LabVIEW and explore the different Marker properties.  There is also an example in the NI Example Finder called niFgen Arb Waveform Marker.vi.  The help file for markers is a good resource for this as well (snapshot attached).  You can specify delay as well with markers.

 

Your second option would be to export your start trigger from the Feign with the niFgen Export Signal.vi.  Every time you resequence your Fgen with a new frequency, you can reassert the start trigger with the niFgen Send Software Edge Trigger.vi, which can be used to trigger a DAQmx operation.

 

I hope this gets you started. Cheers!

Message Edited by Tyler C on 05-15-2009 12:08 PM