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Changng Inputs on existing VI where do I start?

Hey Guys,


First off, I have never programmed (ever) so am probably the worst possible person to be using labview, but I can grasp the basics I think! However the employee I am replacing wasn't such a novice and previously wrote a continuous data acquisition test that we currently use. Now this test works perfectly, and my current task is to set up an identical test to it.

The input is a simple 6 loadcells, wired to a USB-6211 Hub. The exe, that the previous guy made from the labview VI, then feeds back and records all the necessary data.


I could quite easily 'copy and paste' this test exe across onto another test machine and pc using a second usb hub, but I only have the one PC available to use. This PC is already running the first test exe. I am happy enough renaming and creating a new exe from the VI to run on this PC in addition the original.


My main problem is changing the VI so that it doesn’t try to use the existing inputs, but instead uses a second USB hubs (wired up to the new identical test) inputs. This shouldn’t be that difficult I know, but the VI looks to have been made using the queued Message Handler template and I have no idea where to start as my knowledge is pretty basic. The Test Needs to stay the same, it’s purely the inputs I need to alter.


If someone could point me in the right direction as to where I start it would be most welcome! The Block Diagram is attatched



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You did not attach a block diagram - you attached an image, and the USB-6211 is not a 'Hub'. The USB hub is what the DAQ device is attached to.


You will have to find where the connection to the 6211 is specified. It would be something like Dev1/ai0:7. It could be in the code or it could be in MAX defined as a task. Since you did not attach the code, it is impossible to say where this is being done. After you find it, then you also need to make changes to the shared variables so that both exe's do not use the same ones. Impossible to say why shared variables were even used.

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Message 2 of 4

You can either tell your manager to find a more experienced LabVIEW programmer to modify the code or buy another PC.

If I was the manager, I'd buy another PC and be done with it.



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Thanks, I did try not to sound too useless but clearly it didnt work!


I shall have a hunt round ( have been for a while now) for the connection, and attatch the actual code tomorrow. I may go with suggestion 2 though and all the hassle that entails (though it'll at least be hassle i understand).

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