Question about shared variables and report generator

I have a project with about 200-250 shared variables and at every 12 hours i want to make a report containing information about some boolean and double front panel variables linked to the shared variables... Now, i've tried with both the "Write Trace to SpreadSheet File" function from DSC->History and with different functions from NI Report Generation Toolkit. My problem is this: i would like to get my xls file to contain just the timestamps when my shared variable changed value. As it is, the number of rows in the file depends, obviously, on the sampling interval given as input. As an example, in 12 hours, my shared variable would change value maybe 5-6 times. Thus i would like my xls file to contain just 5-6 rows with those 5-6 changes. If i set the sampling interval to say, a matter of seconds, that would mean too much unneeded information in my xls file. Instead, if i set it to let's say 15 minutes, i would probably lose the moment the shared variable changed value. Is there a way for me to achieve my desired functionality with functions from DSC or Report Generation Toolkit? Thanks in advance, Sabin

Hi Mike and thanks for the reply. Actually, my first idea was exactly this: in an event case structure, whenever my variable changed value, i would retain the relevant data in an array and then at the 12 hour period write all of it in a report. However, my boss deeemed it memory unefficient and compelled me to use only one function. Thus my predicament... If you have more advice on this new info, i would be grateful... Cheers, sabin

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I have a Vacuum System That includes signals from - Pumps failure, Valves status, Vacuum gauge, start Pump ...
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Amitai Abramson,
Hello and thanks for using the NI Forums.
I'm glad that you've read the Using the LabVIEW Shared Variable Tutorial on our website. Check out these other resources:
Network Variable Technical Overview
Troubleshooting Network-Published Shared Variables
Why Do I See Unexpected Value Change Events for Shared Variables Using LabVIEW DSC?
All You Need to Know About Shared Variables
Creating a Value Change Event for Shared Variables
Alternative Method for Using Shared Variables Between Systems in LabVIEW 8.x
What Is The Difference Between Using Shared Variables And DataSocket VIs To Access OPC Tags?
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Using a Local, Global, or Shared Variable in Parallel Loops Can Cause Race Conditions
Using Local and Global Variables Carefully
Tutorial: Local Variable, Global Variable, and Race Conditions
Locking a Shared Resource or Variable in LabVIEW Using Semaphores
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Message Edited by Ben S on 10-01-2009 06:05 PM
Ben Sisney
FlexRIO V&V Engineer
National Instruments

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Attachments:
Race condition.PNG ‏57 KB

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"... after all, He's not a tame lion..."
Be thinking ahead and mark your dance card for NI Week 2015 now: TS 6139 - Object Oriented First Steps

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Message was edited by: Maggie

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Message was edited by: AfoUare for typos

Question about shared variables and report generator

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