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Name: Circular Buffer Submitter: hooovahh Submitted: 24 Sep 2014 Category: XNodes LabVIEW Version: 2011License Type: BSD (Most common) Description This package contains functions for maintaining a circular buffer. Create the Circular Buffer using the Initialize Circular Buffer function. This makes a DVR, and the data type of the DVR changes based on the data type specified for the circular buffer. The data type can be any type as long as it is not an array. It must be a scalar. The size of the buffer is specified on initialization but can be changed using the Change Circular Buffer Size function. Add data to the circular buffer using the Write Circular Buffer function. Scalar values can be added, or a 1D array of data can be added. The data type of the values to be written is the data type defined in the initialize function. Read the data back out of the circular buffer using the Read Circular Buffer function. The data type of the read values will be the data type defined in the initialize function. Cleanup the program by destroying the DVR on exit. An example VI Circular Buffer Demo shows how a Circular Buffer can be used. XNode Disclaimer The Initialize, Read, Write, Get Status, and Change Size functions are implemented as XNodes. NI does not provide support XNode development. For an introduction to XNodes read Adam Rofer's "XNodes - A Crash Course" presentation (http://lavag.org/files/file/56-xnodes-a-crash-course-powerpoint). Dependencies LAVA Palette-1.0.0.1 How It Works The source is all open and the template VIs for each XNode is what is executed when the XNode is generated. This means you are welcome to try to further optimize these XNodes by editing the templates. A new instance of the XNode will need to be placed which will force the new code to be used. If anyone finds performance improvements for these functions please feel free to post in the support topic. Because the size of the buffer is practically unbounded, I wanted to avoid unnecessary data copies, which is why it is designed around DVRs. There exists 3 things in the DVR, the buffer size, a pointer to the current write location in that buffer, and the array of scalar values, whos data type is defined during the initialization. Click here to download this file

I don't agree , LabVIEW's OO is almost perfect, if we just had native interface, it would be perfect.

Man you must have a lot of idle time. As far as documentation goes for the binary VI format, all I know is that it basically follows the Macintosh resource format from the good old Mac OS Classic times. That knowledge allows to identify and access the various resources in a VI but of course is just the container format not the understanding of the individual formats of each resource type. While some of them used to be fairly similar to classic Mac OS formats, others and that is the majority of the VI resources, are very LabVIEW specific and the LabVIEW developers more or less threw together whatever they felt was necessary into a C structure and then flatten that to the resource stream. Without access to the LabVIEW C++ source code it is basically impossible to decode these resources in a meaningful way and even more difficult to modify them and write them back into the binary VI structure. VI Explorer really doesn't seem possible to do without access to the actual LabVIEW source code, which would have to be gained either illegally or caused by a preachment of at least some non-disclosure agreement. Also many of the bigger resources are currently ZLIB compressed which adds an extra complication layer into this all. Personally I think your best (and almost only) bet to get at these informations is to apply as LabVIEW developer within NI, but expect them to require you do sign some NDAs before you start, and they will do a good screening and some of your posts in the past may be a bit of an obstacle for that.