Hi Thomas,
I'll describe and show you a great article about how to do this. Also, there are some great examples of synchronization that ship with DAQmx located in C:\Documents and Settings\All Users\Documents\National Instruments\NI-DAQ\Examples\DAQmx ANSI C\
Basically you'll have two tasks: analog input and output. You'll set up a trigger in your AI task who's source will be ai/StartTrigger. Then, you'll just make sure that you start the AI task before the AO task. So the AI task will be armed and waiting for the ao start. You can ensure this by using a sequence structure around the start vis or using the error lines to ensure that one will start before the other. Look at the link before for some great information.
Learn 10 Functions in NI-DAQmx and Handle 80 Percent of Your Data Acquisition Applications: DAQmx Tr...
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