How do I synchronize data collection on two DT3001 boards?

[Kacie]

I am very new to Labview, and I am trying to find an easy way to synchronize my data collection on two DT3001 boards.  I have tried modifying the AI Continuous Scan example.  This works because I am using all 16 channels on each of my boards.  Unfortunately, I cannot find a way to make both boards collect data beginning at the same time.  Is there an easy way to synchronize both boards to collect data at the same time?  Thank you for your help!

[Travis G.]

Hello Kacie,

I'm not sure how your DT 3001 device and it's drivers LabVIEW functions work, but for synchronizing acquisition on two National Instruments DAQ cards, you need to share a start trigger and sample clock between the two cards by connecting the Real-Time System Integration (RTSI) buses of the cards using a RTSI cable.  This provides dedicated lines for sharing the same sample clock and start trigger, and provides highly accurate hardware-timed synchronization.  Any synchronized starting you program in software in LabVIEW will be software timed.  You can use the sequence structure within LabVIEW to group together different portions of code so that all the configuration is performed for both cards first, and then they are started at the same time.  I know this probably isn't too much help, but I would need to know more about how your DT 3001 device and the AI Continuous Scan example works.  You might be able to find better help on this at Data Translation's website.

Travis G.
Applications Engineering
National Instruments
www.ni.com/support