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Problem with DSC logged data viewing

Hi all,
I'm using LV 8.0.1 with DSC module. I'm not able to show historical data from a shared variable when the data type is Int32, while all is ok when the variable is a Double.
I tried with MAX Historical Data Viewer and also programmatically using the Historical Trend express vi from the DSC palette. No success.
On the contrary, if I export to text the trace view from MAX, the correct data are written to text. I noticed that the "Data type" property of the item is 15(Variant) for the Integer variable, 7(Analog) for the Double variable: I believed that an Int32 could be a valid data type itself. Maybe the variable is stored but not displayed correctly?

Paolo
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LV 7.1, 2011, 2017
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Got some progress. UInt32 will be graphed correctly, Data type is 11(BitArray) Smiley Surprised.
I can live with unsigned values but I wonder if some other surprises are behind the corner (I've been working with shared variables for 4 days only!).
Paolo
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LV 7.1, 2011, 2017
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Highlighted

Greetings Paola,

 

How is your progress? I am not aware of any other surprises with using unsigned integers or doubles. That’s great you are harnessing the power of shared variables! One of my favorite application notes on shared variables is:

 

http://zone.ni.com/devzone/cda/tut/p/id/4679

 

Have you read it? After you have a chance to push through this lengthy app note, I’m sure any uncertainties will clear up.

 

Thanks again for contacting National Instruments and if you have any further questions feel free to send us a post.

Jordan Randall
National Instruments Italy
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Thank you Jordan, for now I will keep on using unsigned values, this works well. I already knew the application note you mention: it helped me a lot.
On the other hand, the problem was more on the Citadel database archiving/viewing than on the shared variable side. In the meantime I read other documentation about the database management, increasing my skills on this subject.
Thank you again
Paolo
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LV 7.1, 2011, 2017
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I got the same problem with LabView 8.20. The exported file prints all data right, but the Trace View window in MAX keeps saying no data. No chart or graph is showing up.

This the exported data file.

NI (c) Historical Data Viewer v2.0                           
Created: 12/19/2006 3:32:42.806 PM Pacific Standard Time
Number of rows: 1928
Interpolation interval: 0 seconds

Row,Time,\\M2StripChart\ArrayTest\M2StripChart\ArrayTest\Ana_1_0
1,3:29:26.806 PM,0
2,3:29:27.336 PM,0
3,3:29:30.046 PM,0
4,3:29:30.046 PM,0.738053
5,3:29:30.147 PM,0.919008
6,3:29:30.246 PM,0.707745
7,3:29:30.346 PM,0.430689
8,3:29:30.447 PM,0.549774
9,3:29:30.546 PM,0.149324
10,3:29:30.647 PM,0.121594
11,3:29:30.746 PM,0.372856
12,3:29:30.846 PM,0.850488
13,3:29:30.947 PM,0.391185

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