Synchronizing multiple PXI cards with Data Aquisition Toolbox

Hi

I am using the following National Instruments hardware: 3x PXI-6733 Analog output, 2x PXIe-6535 Digital output, inside an PXIe-1078 Chassis.

What I am trying to do is to generate synchronized output on all 5 boards. In LabView, using the DAQmx driver suite, this is simply done by telling all 4 of the 5 boards to use the on-board clock of the 5th board instead of their own. All clocks are available to all boards through the chassis anyway.

Now I am trying to do the same thing in Matlab, using the Data Aquisition toolbox. What I have found so far is the 'ClockSource' property, which can be set to 'ExternalScanCtrl'. One can then set the 'ExternalScanClockSource' property to any PFI or RTSI channel.

My problem with this is that I dont see any option to make any of the clocks available on an RTSI channel. The PFI channels would require external cabling, which doesnt make any sense, since the boards are hardware-connected inside the chassis already.

Basically, what seems to be missing in the Data Acquisition Toolbox is a simple way of using the sample clock routing possible in DAQmx. I assume other people must have run into the same problem, since synchronizing multiple input/output cards must be a common task.

I would greatly aprpeciate any suggestion how to solve this elegantly in Matlab.

Thank you Sebastian

Answer 1

[Stephan]

Can you post your LabView code for those cards? I have problems getting the exact same setup up and running. Somehow I'm unable to synchronize both digital output cards with a master card.