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General question about iterations

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I think the "Region of Interest" is one of the propety node and it been used in the camera block. A lot of other stuff did the same.

 

BTW, where the error wires you think should start at?

 

Thanks

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Okay, the "Region of Interest" is connected to a property node, but it's well nigh impossible to figure out what that is a property of with what I've got on my screen.

 

As for the error wires, they are usually used to (1) enforce the order of consecutive actions (which you are also doing with frame sequences) and (2) show the writer what and where errors occur when running the program. Even if you don't need them for (1), when your program has problems, then the error indicator can be indispensable. For example, in your "Sweep Conditional" case (to the right in the BD), you have four separate error wires which start at VISA writes and then just stop. If there is an error with any of these, you'll never know it, because you don't have them wired to an indicator. Usually, you start with one "error in" control at the beginning of your program and end with an "error out" indicator (or the "error handler" subVI you have somewhere on the right), and everything which can take an error wire is connected in some way in between.

 

Some additional unrequested advice: Modularize your program, so different functionalities are packaged in separate subVIs. Then you can test each one individually and then sequentially as you build the program. It also makes things a lot smaller to draw (easier to read), and you can avoid your 3-4 screen length wires. Throw out the sequence frames, so you don't have to figure out whether you're going left or right within a sequence (use state diagrams and shift registers when needed as Mark suggested, they're much more accommodating to changes in the data flow). And don't wire into the right side of an indicator or the left side of a control - it just makes things that much more difficult to read quickly.

 

Cameron

 

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