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Buffered Variable Table (BVT)

Hi Ricardo,
 
Thanks for your reply. I looked at the RTT. A fair amount of stuff in there that could come very handy - eventually - but it seems a bit overkill for what I want to do. Initially, I thought and still think that an implementation of the CIE based on BVT without going into TCP communication etc... would be good. Pretty much similar to the CIE-CVT one. Giving the option to choose the buffer size in the BVT would also be a good feature, right now it seems it is either 1000 (buffered selected) or 1 (buffered unselected). Choosing a buffer size, and running the BVT as a circular buffer would be good.
 
So, what I want to do is relatively simple: I want to acquire with a scan engine rate of say 10ms, but only make available to the rest of the application data that are averaged over say 100 points, which would provide an averaged data point every 1 sec. However, I want to be able to write data, as soon as the scan engine cycle and not wait 100 iterations. So instead of fiddling with the latest TCE and its non-alignment with BVT, I'd rather slightly modify the core of the CIE Scan.vi to average the data at each iteration (the average is weighed, so the CVT always contains a usable value). Now with this, when the iteration reached the "virtual buffer size" value, that I got my averaged data over the desired # samples. Obviously this is only for DBL type and cannot be directly applied to BOOL, ENUM, STR...
 
CVT_VirtualBuffer.jpg
 
One thing I wonder is the performance toll of doing a read followed by a write from the CVT (instead of a single write). But after initial tests it doesn't look bad. I think it is still better to do it this way than to carry additional queues for computing the average at the end (in this case we would have a real buffer, not virtual).
 
Laurent.
Blue System Integration
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Hello,

 

BVT provides timestamped storage for values and this is what I was looking for. Unfortunately,Tag Configuration Editor does not work with labVIEW 2018 Is there any update for this component?

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