Pass Boolean b/t parallel threads

Dear Labview Board,
I have two Labview processes that run in parallel. One performs data input and the other data output. They where originally designed to run independent of each other, but today I need them to perform some modest integration. Both processes are very complex, so I would like to avoid a costly rebuild. I'm looking for a quick and dirty solution.
I need process #1 (which is loop based) to temporarily hold execution based on a condition (Boolean indicator) in process #2. I am not familiar with parallel processing techniques in labview, and I'm wondering if I'm making this harder than it really is. Can I place a wait loop in one process that references an indicator in another process? What is the easiest way to pass Boolean data between parallel threads?
Thank you,
Zach
Solved!
Go to Solution.

F. Schubert wrote:
It is written in only one place [..] global variable?
Yes.
Felix
"But can't I get away with just using a penny instead of a fuse for now?"
For the current application and assuming
1) the code will never change and
2) if it does change you will be that person and
3) you will remeber you used a global and
4) also remeber that gloabls have the potential of a race condition.
I code by the hour and do so such that my customers can confidently twaek their app without getting me involved. If I have to be involved, then I failed in my goal (sorta like what I do here on the forums )
So if the question is "can I get away with it?" then yes.
"Would I allow one of my rookies to do it?" NO
Ben
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction

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How to use notification with parallel thread

Hi,
I am learning to use Notification to communicate between thread. I still don't know how to use it. In my current project I have a case to use this so I think I should implement this technique. My example is I have a main sequence in that I make a new thread. What I want is the new thread will do a task A when receive a notfication or to exit the thread when the main sequence stop.
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Solved!
Go to Solution.

Hello,
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.mrLeft{float:left} .mrInfo{border-left:solid 1px #989898;font-size:x-small;color:#989898}
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Parallel threads does not work with brtools 7.20(12)

hi,
I am trying to rebuild an index online with BRTOOLS 7.20(12) and trying to specify parallel threads more than 1 which does not seem to accept, is this a know issue .
BR0657I Input menu 356 - please enter/check input values
Options for rebuild of indexes: SAPSR3.VBOX~A (degree 1)
1 * Rebuild action (action) ................... [rebuild]
2 - Rebuild mode (mode) ....................... [online]
3 ~ New destination tablespace (newts) ........ []
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5 ~ Index parallel degree (degree) ............ []
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BR0662I Enter your choice:
BR0280I BRSPACE time stamp: 2011-08-16 17.27.17
BR0663I Your choice: '4'
BR0682I Enter integer value for "parallel" (1-1) [1]:
BR0280I BRSPACE time stamp: 2011-08-16 17.27.20
BR0684W Invalid value for "parallel": '4'
BR0682I Enter integer value for "parallel" (1-1) [1]:
BR0280I BRSPACE time stamp: 2011-08-16 17.27.41
BR0684W Invalid value for "parallel": '4'
BR0682I Enter integer value for "parallel" (1-1) [1]:
BR0280I BRSPACE time stamp: 2011-08-16 17.27.43
BR0684W Invalid value for "parallel": '2'
BR0682I Enter integer value for "parallel" (1-1) [1]:
BR0280I BRSPACE time stamp: 2011-08-16 17.27.47
BR0684W Invalid value for "parallel": '3'
BR0682I Enter integer value for "parallel" (1-1) [1]:
BR0280I BRSPACE time stamp: 2011-08-16 17.27.49
BR0683I New value for "parallel": '1'
thx Jonu

Hi,
you can check in option itself, range is 1-1
BR0682I Enter integer value for "parallel" (1-1).
try with Index parallel degree.
thanks
ashish

Passing boolean values to DLL

Hi,
Currently I am using VB .NET to pass a boolean to a DLL... i've tried this with Strings and did not have a problem... but when i want to pass booleans over, i got a 'System.EntryPointNotFoundException' error ...
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attached is a simple code... hope i did it correctly...
Best Regards,
JQ
LV 8.0 user...
Attachments:
display.zip ‏66 KB

JQ wrote:
thanks tst and dave... i think this may be the problem ...
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quoted from: http://zone.ni.com/devzone/cda/tut/p/id/3188#toc1
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Quick question on passing booleans

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Yup:
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Hi guys,
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Solved!
Go to Solution.

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Pass boolean parameter?

I need to pass a boolean (true/false) for load complete, so i can shrink down tons of codes.
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I don't know about passing arguments via listeners, but as far as conditionals go, "=" is not what you want to use... "==" is for comparison. And if you are testing boolean values you don't need to write out the comparison....
if(pass){
} else {
And as I said, I don't know about passing arguments via listener function designations, so if you've had success doing that before, then fine. I have been led to believe it is more complicated a matter to resolve. Without knowing how to do it otherwise, while it might involve more lines of code, I would use the conditional test to assign the listener rather than to decide which code to use in the loadComplete function. So I'd use one of two listeners and one of two complete functions thru them..

Passing booleans to LabView dll

I have created a Labview vi (7.1) that I have converted to a dll which uses a cluster of Booleans as a input. I set Test Stand (2.0) to pass a Structure (1 byte boundary) with Booleans as the data type (Test Stand also asks for a numeric type for some reason); is this the correct method? I get the message 'no type information in the dll' when loading the dll from Test Stand, is this normal for Structure/Cluster passing?

Hi Steve,
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http://digital.ni.com/public.nsf/websearch/DBCE27265FFB554986256C9400026FE8?OpenDocument
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Useful other threads below :
http://forums.ni.com/ni/board/message?board.id=170&message.id=122260&requireLogin=False
http://forums.ni.com/ni/board/message?board.id=330&message.id=6140&requireLogin=False
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// it takes almost no time to rate an answer

How to pass the caught exception in Thread.run back to the main program?

I have following three Java files (simplified from a real world application I am developing, see files at the end of this posting):
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One work-around:
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The problem is, where could you catch it anyway?
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A thread runs in a separate, er, thread, that the catch(SomeException) isn't running within. Get it?
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Passing boolean parameters to Oracle

Hello there everyone.
I have just started to work with Oracle stored procedures. I
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Hi Phil thanks for replying!
I continued searching Google and came up with the same
conclusion you mention. Here are a couple of links:
http://www.oracle.com/technology/tech/java/sqlj_jdbc/htdocs/jdbc_faq.htm#34_05
http://www.utexas.edu/its/unix/reference/oracledocs/v92/B10501_01/java.920/a96654/tips.htm #1005343
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I will change my boolean parameter to be something more SQL
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Barry

Pass Boolean b/t parallel threads

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