Synchronous sampling of PXI-4300 and PXI-4353

[MattFu]

I have two cards (PXI-4300, PXI-4353) installed at PXIe-1071. PXI-4300 is used to measure voltage, which sampling rate is 2000. PXI-4353 is used to measure temperature, which sampling rate is 10. I use a while circulation with a cycle time of 2.5 s. I don't how to make sure that the two cards start sampling at the same time in each cycle.(Because it spends more time to measure temperature, so when PXI-4300 is done, but PXI-4353 is still sampling.)

[Bob_Schor]

We don't know what you tried because you failed to attach the VIs you used.  Don't bother attaching pictures -- attach the VIs, themselves, please.

Are you using the PXI as a LabVIEW RT device, or are you running Windows inside its Controller?  What version(s) of Windows/PharLap/LabVIEW are you running?

Bob Schor

[MattFu]

Hi, Schor

      Thanks for your response. I installed a controller(PXIe-8840 QUAD CORE, WINDOWS 10 64-BIT) to the chassis(PXIe-1071). I used LabVIEW 2015 to measure temperature and voltage. But I don't know how to achieve the process I mentioned before.

      Now I use a Flat Sequence Structure to make sure the two cards start sampling at the same time, but it's not precise. 

      How to calibrate one card's clock by another one? How to get the clock of the card?

      Thank you !

[Bob_Schor]

Pictures of small sections of code are useless to me.  Imagine if I sent you a picture of 20 lines from somewhere in a 500-line C++ (or Matlab, or Python) routine and asked why my program didn't work ...

Does your PXI box have a Timing I/O board installed?

Bob Schor

[MattFu]

Em.. Actually I haven't finished the LabVIEW code now, I just don't know how to make the two cards start sampling at the same time, the others are details.

I think my PXI board has a Timing I/O, but I am not sure, since I never used it before. The fig.1 and fig.2 are selected from the manual, could you please check whether it has or not?

Thank you! 

Matt Fu

[Bob_Schor]

A PXI system typically has the following three components:

1. A "Chassis" (what I call the "Pixie-Box").
2. A "Controller", which typically plugs into the PXI in Slot 1.
3. One or more plug-in boards.  Many Chassis (mine is one of them) have a "Timer I/O" board plugged into Slot 2, providing a common fast, accurate clock and other timing signals to the remaining plug-in boards.

Can you provide a full description of your PXI system?  What Chassis do you have?  What Controller?  What boards are plugged into which PXI slots?  [In addition to providing the words to answer these questions, you could also include a photo showing your PXI box ...

MyPXI

Here's a picture of one of my old boxes.  The Controller is in Slot 1, the Timing I/O board in Slot 2, and a Multi-function board (A/D, D/A) in Slot 8.

Bob Schor

[MattFu]

My Chassis is PXIe-1071, Controller is PXIe-8840, two boards are PXIe-4300 and PXIe-4353.

Here is the picture of my PXI box.

my PXI box

Matt Fu