PXI-6561 Synchronous Acquisition

[bmann2000]

I would like to sync the Digital Acquisition of 72 LVDS channels, I'm using 6 PXI-6561 cards, 12-channels per card, sampling at 2MHz.  I'm using LabVIEW 8.5.1, an 18-slot PXI-1045 chassis and PXI-8106 controller.  I figure DAQmx is now the easist option, never used it, but have the Data Acquisition and Signal Conditioning Course Manual.

Any pointers to example code, or tips on getting started much appreciated.

[Tom O]

Hi bmann2000!

To get you started on this application, there are a number of examples within LabVIEW that you should find useful:

Go to Help » Find Examples to open the example finder. Next, browse to Hardware Input and Output » DAQmx » Synchronisation. Within this folder are a number of examples that will show you how to synchronise multiple devices together, as well as different tasks on the same board. You may find Multi Device » Multi-Device_Synch-Analog Input-Cont Acquisition.vi to be of particular interest.

Have a look at those examples and post back if there's anything specific you'd like to ask, or if any of the examples don't make sense!

Hope that helps.

Best regards,

[bmann2000]

thanks for the quick reply, the examples was the first place I looked,  I was also searching the LabVIEW palette for daqmx.  I figure I'm using niHSDIO VIs with the 6561, which are a subset of DAQmx VIs ?.  I suspect I don't have the correct items installed to start development.  I opted for factory installation service, so assumed the correct components would be installed to match the 6561 cards (and 6123 cards).  Attached are screen dumps of the examples directory structure and of MAX software components.

Can you advise on the steps required to determine if I have the correct components installed ?

[bmann2000]

i've found the examples under "modular instruments", discovered the "limit search to hardware" tickbox. 

How do I check that LabVIEW has the all VIs installed for 6561 and 6123 cards ?

[Tom O]

Hi again,

Sorry, I misread your original post! Yes, you'll need to use HSDIO drivers with your cards, which are separate from DAQmx. All our instrument drivers, however, are pretty straightforward to use and not dissimilar to DAQmx.

You should have all the VIs you need for the examples as long as you have the NI-HSDIO drivers installed. You can download them here - it sounds like you already have them though!

Have a look through those examples instead. In fact, the DAQmx examples can still be useful to you in conceptual terms of what they're doing. You need to define a sample clock and export that from a "master" card to the other cards on the PXI trigger lines to synch them all together.

Have a look at these examples and post back if you need more help with setting up the application!

Best regards,

[bmann2000]

still struggling to find 6123 examples, search view attached

[Tom O]

Hi,

The added complication here is that the 6123 uses DAQmx and the 6561 uses HSDIO. Either way, your examples folder is looking a bit empty, so give this a try:

• Go to Control Panel » Add/Remove Programs
• Select National Instruments software and click Change/Remove
• Find DAQmx and HSDIO in the resulting list.

At this point, you have a couple of options:

• Click "Modify" and check the installed components. Find your version of LabVIEW and make sure that examples are installed (see below)
  
  
  
  
• Click "Repair" to replace the driver files
• Un-install and re-install both the drivers (making sure that examples are included!)
  

Hopefully you should be able to see the examples at this point. Failing this, I can post some on the forum for you - it would be better for you to have a full library though!

Good luck!


Message Edited by Tom O on 07-03-2008 10:55 AM

[bmann2000]

any idea what location I point to?  I put the 'Device Driver Reference CD' (501648B-01) in a USB CD drive, also tried the LabVIEW 8.5.1 CD (501327E-01), am I using the correct CD, do I need to point to a particular file, or call the CD E: or something ?

[bmann2000]

another day, inserted the Device Driver CD again, and today it works, examples now populated 🙂

i was using a USB yesterday, so perhaps windows got confused between the CD and USB drives due to all the in-and-out of the usb stick, probably me not ejecting the USB properly.

[Tom O]

Hi,

That's great news! I hope the examples are useful for you!

Regards,