PXI-board only returns perfect sine wave

Hi, everyone!
This is a strange one:
Im peforming synchronized sampling from two boards; one is a PCI-6224 in my computer and the other a PXI-6229 located in our PXI-system. Being a rookie when it comes to labview, I was quite proud of myself for managing this all by myself. However, when i looked closer at a 10 sec test-record I noticed something peculiar. Although none of the 32 (differential) channels had inputs during the recording, the PXI-board returned 16 perfect 1 Hz sine waves with exactly the same amplitude as the measurement range. Attaching a signal to the terminal block didn't alter this. The PCI-board returns only weak 50 Hz (power network) noise, as expected. What is going on ??
I'm using a PXI-1031 chassis together with a PXI-8184 controller connected to the PC with a network cable. I trigger the pxi-board by sending the PC-clock through a PFI-port and a physichal wire.
regards, Einar

As I said, I haven't used LabVIEW 8 all that much. It's a bit tricky: you'll have to make a new Project, add the PXI as a new Target, and the add the VI you're trying to run underneath the new target. The last time I was playing with this I also had to open some ports in the Windows XP firewall.
If this is all a bit much for you, you might have a PXI controller that is configured to dual-boot both LabVIEW RT and Windows XP. If you reboot the controller in Windows XP mode, you can then access the PXI-6229 in the same way you currently access the PCI-6224... provided you don't mind copying the VIs over and hooking up a mouse, monitor, and keyboard to the PXI.
Switching from LV RT to Windows XP is most easily done by selecting the appropriate option in the PXI's BIOS. Check your PXI controller's manual for details.

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Message Edited by awais.h on 03-30-2010 11:20 PM
Message Edited by awais.h on 03-30-2010 11:21 PM
Solved!
Go to Solution.

Hi
Thanks for the code but I'm afraid it won't work. Like you said the probability of choosing a value that is on both graphs may not happen. This is something that I would like the code to do automatically.
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Go to Solution.
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PXI-board only returns perfect sine wave

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