Help with continuous voltage accuisition.

[Punchy_Cupcakes]

I've written a program to measure 30,000 points of voltage data over a specified amount of time (Called "sweep time"). When the sweep time is set to <=8.33 seconds, the program works without any difficulty. However, when sweep time is set to >=8.34 seconds, only half of the required data, 15,000 points, is taken. This sweep time corresponds to about 300 pps, so I thought it might have something to do with my hardware, but when I rewrote the program with a virtual voltage channel the same thing is happened. What could possibly be causing this? The data is printed onto a spreadsheet whose default location is "C:\Users\localadmin\Desktop\test_print". This can be changed in frame 2 of the stacked sequence. This spreadsheet file can be opened with Excel, which is how I have been determining the number of data points being recorded. (When the problem occurs, you will see a 0 on the last 15,000 voltage data). I've attached the VI in question. Any help would be greatly appreciated.

[johnsold]

Your VI did not get attached. Please try again.

Lynn

[Punchy_Cupcakes]

Right. good catch. Here it is.

[Punchy_Cupcakes]

Well, since that is not working for some reason. Here is a link to i t in my drop box folder.
https://dl.dropboxusercontent.com/u/21370499/Taudaq6Virtual.vi

[johnsold]

It attached that time. Using the Review button above the toolbar on the Post Message page has been known to remove attachments. I never use it so I donot know whether they ever fixed that or not.

I do not see anything obvious.

What is your hardware? Some devices have minimum sample rates. The change from 8.33 to 8.43 causes the desired sample rate to go below 300 samples per second. The sample rate and number of samples are used to set buffer sizes, so it might have something to do with that. I would expect some kind of error or warning. You might change the type of dialog on the Error Handler.vi to include warnings.

Lynn

[RavensFan]

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