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How do I synchronize a DSA (4496) board with several S-series (6143) boards for PXI?

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I need to configure a data system that will require phase-locked measurement for accelerometers and dynamic strain signals.  How do I synchronize my PXI-4496 board with my PXI-6143s?
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With reference clock synhronization, master slave devices lock their ADC over the sample clock to the shared 10MHz reference on the PXI chasses backplane (PXI_CLK10). For detailed instructions on how to do this, reference the Synchronization section in NI Dynamic Signal Acquisition User Manual

 

Regards,

Glenn

Applications Engineer

National Instruments

 


Regards,
Glenn
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Thanks, but this information has not help me to determine how to program the synchronization in LabVIEW (version 8.6.1).  I tried using the built-in synchronization example, but none of the configurations match what I'm trying to do.  Has anyone else tried to synch DSA and S-series boards?

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What example did you use? I was able to find the following example in the Example Finder that should be good start to your application.

 

Hardware Input & Output>>DAQmx>>Synchronization>>Multi-Device>>Multi-Device Synch-Analog Input-Cont Acquisition.vi

 


Regards,

Glenn

Applications Engineer

National Instruments

 


Regards,
Glenn
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Glenn,

 

That is the example I tried.  There is no instance of that example that is compatible with both boards.  There are examples for multi-device "M" series (PXI and PCI; no S or DSA), "E" and "S" (no DSA), or DSA (no S).  I even tried mixing and matching properties, but can't find the right formula.

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What sample rate did you want to achieve? Keep in mind that since you are using a DSA device, its oversampling clock restricts its sampling clock to a fixed set of sampling rates, which can be found in the manual. That example we discussed using the case statement 3 (DSA Sharing Sample Clock) should do the trick if you are using the DSA as the Master. Can you elaborate on why this does not work for your application? Are coming across any errors, are the signals not syncronized?

 

Glenn


Regards,
Glenn
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I get error -200452 from the slave property node (the 6143s).  It says that SynchPulse.src is not supported by the device or not applicable to the task.

 

Sampling rates between the master and slaves are equal.  Currently, they are 20Ksamples/sec/channel, but may go as high as 80K.

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Solution
Accepted by topic author AEI_JR

I overlooked that some of the DSA properties doesn't directly translate to the S-series devices. I was able to find a KnowledgeBase article that addressed your specific issue.

 

Synchronizing Dynamic Signal Acquisition (DSA) Products with NI-DAQmx, this includes an example program Synchronizing a DSA Device and MIO Device to Sample at the Same Rate.


Regards,
Glenn
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Glenn,

 

It works!  Thanks for sticking with this.  Note to other users:  the example is in LabVIEW 7.1.  When using newer versions, you will have to manually browse to the location of one of the subVIs, being that it is in the example folder, not the VI.lib folder.

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