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liakofan

Unexpected Error from specific shared variable in RT PXI

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Hello everyone,

Basically i have 2 VIs, one running on a PXI, lets call it PXI.vi and one on the pc, GUI.vi

I started testing my application some days ago and after 3 hours of running i got the error in the picture.

Error -1073807339 occured at VISA Write in PXI.vi

Reason: Timeout expired before operation completed.

Then immediately also this error:

Unable to locate variable in the shared variable engine. Deployment of the variable may have failed.

I restarted the PXI and started the test and it happened again after 2 hours.

The third time even sooner.

It is always 2 variables that cause this problem.They are used to pass information about error happening on a instrument.

So actually they are not even used when giving the message.

I check them in a loop every second.

They are not buffered. I initialize them when the vi starts

I am using Labview 2011 and windows 7

Thank ou in advance for your time.

post-18391-0-88727500-1328864541_thumb.p

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Maybe someone else has the same or similar issue so i post what seems to be the solution.

I changed the address of the shared variable. It had the DNS name of the PXI and i changed it to the IP address.

I don't believe it should make a difference but it stopped giving an error.

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I wonder if your DNS server was unavailble momentarilty, and couldn't resolved the IP address?

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A lease time of 2-3 hours from your DHCP server could break this too, if the PXI got juggled to a different IP and the DNS simply hadn't propagated to the PC yet.

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you to start from the beginning to rectify the deployment problem.

-- their must be same version of labview on both (host and target), i.e, if you are using labiew 11 on host then it must be labview 11 on target(Pxi).

-- make a proper real time format code.

-- for real time, shared variable selection is more important (no. of sample, clock....etc)

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A lease time of 2-3 hours from your DHCP server could break this too, if the PXI got juggled to a different IP and the DNS simply hadn't propagated to the PC yet.

I guess this would also break the version where the IP address is used instead of the DNS name.

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