User event or event structure time-out

Hi,
I have two VIs one is a producer, one consumer.
The consumer VI is called programatically (i.e. not wired) when the producer VI is run
Both have user interfaces using an event structure.
I have a control on the producer that i wish to use to trigger an event in/pass a value to the consumer VI. I have implemented this in two ways, but am not sure which is the 'preffered solution'.
Solution 1:
Detect control activation in the producer VI using event structure, load new value in to a global variable.
Use the time out event case in the consumer VI to load the value from the global variable.
Solution 2:
Set up a user event in the producer VI, load the Event Registration Refnum in to a global variable, use the event structure to create a new event when the control value is changed by the user.
Use Event Registration Refnum global variable in the consumer VI to trigger the event structure (loaded once, when the VI is first loaded).
Solution two means the time-out event case does not need to be active, meaning the consumer VI will be doing nothing except waiting for either the user event, or direct user interaction. It will also not have the potential time delay of up to 1 x the time-out value of the event structure. It does require a sequenced start of each VI for the Event Registration Refnum to be loaded in to the global variable before the global variable is read by the consumer VI.
My end application will be utilising a number of consumer VIs and will require user interaction information from the producer to be passed to them. Which proposed structure would be the generally accepted better practice?
...or if i've missed the best solution, where should i be looking?
Thanks,
Blue
(xp, LV 8.6)

Example of Queue based function Globals.To store the events and data.
http://forums.ni.com/ni/board/message?board.id=170&message.id=240328#M240328
Balaji PK (CLA)
Ever tried. Ever failed. No matter. Try again. Fail again. Fail better
Don't forget Kudos for Good Answers, and Mark a solution if your problem is solved.
Attachments:
AI Queue.vi ‏30 KB
DAQmx AI.vi ‏59 KB

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Nickerbocker wrote:
If an error is generated on the first itteration, then the loop is terminated with that error line. Right?
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In article <[email protected]>,
new_user wrote:
> Hi,
>
> Yes I will gladly post my VI.There are (2) block diagrams. The
> 'setpoint' ring controls should invoke the upper block diagram in the
> event of a selection.
> The lower block diagram should be invoked when the 'Initialize
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I am using many events structures in my application,but i am getting caught in my problems ,can any body tell me abt events programming on time out

i have extensive gui application ,i am using events ,but i am caught,i want to konw abt events ,there pros and cons,time out ,how to program in time out

It is unclear as to exactly what you are asking. The event structure is very handy for monitoring front panel activity and performing tasks accordingly. The default event in the event structure is the timeout. In order to set the timeout you just wire the amount of time before timeout (in ms) to the timeout terminal of the structure. You may have tasks that you want to perform at timeout or you may just have an empty case. I strongly suggest using a timeout and putting the case structure in a while loop in order to keep monitoring the events until the loop exit condition has been met.

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I am a new user for LabVIEW. And I met a problem which really frastre me!!! Hope someone can help me out. Thanks in advance!
I simply want to use event structure under timed loop, which is extrmely important in my design.
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Since it looks like you are new to the whole RT and machine control, I recommend giving this a good read: NI LabVIEW for CompactRIO Developer's Guide
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Yes they can coexist, but not how you did it.
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Message Edited by TonP on 09-26-2008 07:34 AM
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User interfaces and event structures

I am just learning to use event structures to improve operation of front panels. At the moment, I am working on a tab strucrture we use to montinor/set program paramters. VArious parametera are displayed on each tab as controls (not indicators) and are constanly updated sice they can be modified elsewhere by other pieces of code. We controls are normally disabled via a property node so they behave more like indicators and the values are updated by writing to a local variable (I know this is evil but it works in this case). There is a boolean on each tab that toggles between "monitoring" and "changing" modes (or states). When toggles to "changing" (or setting) parameters the monitoring activities are suspended and the control are enabbled. After making the desired changes the controls are either read and the changes implimented or get rest based on some other boolean controls, the parameters controls are then disables and monitoring resumes. The issue is that many users fing the need to toggle between "monitorsing" and "changing" modes to be confusing. I want to replace this switch with an event. If the user clicks on any of the parameters controls in a tab, I want to go into changing mode rather than using the "monitoring"/"changing" boolean control. All other asspects are handled as before. My problem is than if I use a mousedown event to go into "changing" mode and the user clicks on several parameters to shift the keyboard focus to edit more than one parameter, these subsequent mose clciks get processed as new events when change mode is exited. This means that as soon as it returns to "monitoring" mode it jumps immeadiately back to "changing" mode. How should I structure the events to avoid this problem?
Thanks,
--Lee

Lee,
Instead of using a "mouse down" event, use a "value change" event for each
of the controls. Then your program can switch to the "changing" mode
whenever the value of the control is actually changed.
TJW
"Lee Robertson" <[email protected]> wrote in message
news:[email protected]...
>I am just learning to use event structures to improve operation of front
>panels.  At the moment, I am working on a tab strucrture we use to
>montinor/set program paramters.  VArious parametera are displayed on
>each tab as controls (not indicators) and are constanly updated sice they
>can be modified elsewhere by other pieces of code.  We controls are
>normally disabled via a property node so they behave more like indicators
>and the values are updated by writing to a local variable (I know this is
>evil but it works in this case).  There is a boolean on each tab that
>toggles between "monitoring" and "changing" modes (or states).  When
>toggles to "changing" (or setting) parameters the monitoring activities are
>suspended and the control are enabbled.  After making the desired
>changes the controls are either read and the changes implimented or get
>rest based on some other boolean controls, the parameters controls are then
>disables and monitoring resumes.  The issue is that many users fing
>the need to toggle between "monitorsing" and "changing" modes to be
>confusing.  I want to replace this switch with an event.  If the
>user clicks on any of the parameters controls in a tab, I want to go into
>changing mode rather than using the "monitoring"/"changing" boolean
>control.  All other asspects are handled as before.  My problem
>is than if I use a mousedown event to go into "changing" mode and the user
>clicks on several parameters to shift the keyboard focus to edit more than
>one parameter, these subsequent mose clciks get processed as new events
>when change mode is exited.  This means that as soon as it returns to
>"monitoring" mode it jumps immeadiately back to "changing" mode.  How
>should I structure the events to avoid this problem?
>  
> Thanks,
>  
> --Lee

User event or event structure time-out

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