I am having trouble with DAQ Assistants used for sending and receiving a Gaussian modulated sine pulse though piezoelectric actuators attached to an aluminum plate. I have two DAQ assistants, the first one generates a pulse and sends voltage to actuator 1. The second DAQ assistant measures the voltage given by vibrating actuator 2.
How do I ensure synchronization (in time) among the two DAQ assistant outputs? I get time vs voltage plots for both in excel (see attached). But the time for input DAQ seems to be later than time for the output DAQ. Ideally, I would like both DAQ assistants to "start at the same wall-clock time" - "do their job" - "stop after a few hundred micro-seconds" - "write sent/received data to a file".
I sought out to solve this by re-configuring my vi in the following way (See attachment below). However, now I am having trouble identifying what my trigger 'source' should be. Everything I am trying gives me an error.
Please help if you can. Any input is welcomed.
Thanks in advance
I have attached my VI below.
Thanks in advanced,
I am having trouble with DAQ Assistants
Yes. That's what they're best known for around here. Trouble when someone has a non-trivial DAQ need.
I'm not at a LV machine and don't have time to lay out a complete tutorial. Here are a few breadcrumbs for you to give you a little bit of a starting point:
Do a search for "Learn 10 Functions in NI-DAQmx ..." (the rest of the title is something like "and solve 80% of your DAQ problems"). Read the Article. Play with MAX. Resolve to banish the Dreaded DAQ Assistant (and its Evil Twin, the Dynamic Data Wire) far, far away.
Here is a good KB article that talks about how you can go about synchronizing analog outputs without using the DAQAssistant.
How to Synchronize Analog and Digital Output Tasks in NI-DAQmx With LabVIEW
https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000019PBVSA2 - This will give you example code on how to synchronize two analog output tasks using DAQmx
Learn 10 Functions in NI-DAQmx and Handle 80 Percent of Your Data Acquisition Applications
http://www.ni.com/product-documentation/2835/en/ - The article that Bob Schor mentioned, also an awesome resource that I always recommend to customers