Stuck with making my event structure examine if two arrays are equal

Hi there, I'm new to labview. I'm trying to write an event structure; examining if one array equals another array. The program will carry on if they are equal, otherwise it will continue checking... Any help is appreciated.
My program is attached.. It is eventually going to be a memory game when I get it working..
Sequence 1, case structure 10 is were I'm stuck with the case structure.
Thank you in advance
Attachments:
attempt 2.vi ‏18 KB

Seems to me like you should implement a true State Machine. This way you can repeat states and/or jump states as needed.
State Machine
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines

Similar Messages

SubVI with while loop + event structure not working in multi tab VI

Hello Everyone,
I am developing an interface for the control of a prober using Labview 2012, and I am stuck with some issue.
To start with I provide you with a simplified version of my control interface VI, and with the sub-VI used to build and manage the wafer maps.
The VI consists of several tabs: Prober Initialization, Wafer Handling, Wafer Map, Status, Error.
The sub-VI can:
1/ initialize the grid to display the map (sub VI Init Grid not provided here)
2/ import XY coordinates from a txt file (sub VI Wafer Map Import)
3/ display the coordinates and index of the die below the cursor
4/ and when a die position is double clicked, and the boolean "Edit Wafer Map" is true, then the user can change the state (color) of the die between On-wafer die and Selected Die
My issue:
If I use the sub-VI by itself, it works fine. However when I use it as a sub-VI in the tab "Wafer Map", the map does not build up and I can no further use the embedded functionalities in the sub-VI.
I suspect the while loop + event structure of the sub-VI to be the bottleneck here.
However I don't know which way to go, that's why I'd be glad to have some advice and help here.
Thank you.
Florian
Solved!
Go to Solution.
Attachments:
Control Interface.zip ‏61 KB

Hi NitzZ,
Thank you for your reply.
I tried to save the VIs in LV10, please tell me if you can open them now.
Inside he event structure there is quite some code, and since I don't want to make the main vi too bulky, I would like to keep it as a sub-VI.
As you can see from the sub-VI, the event structure is used for extracting cursor position and tracking the double click action. These events are linked, through a property node, to the image "Wafer Map" which is passed to the main vi through connector pane.
All values are passed this way as well (through connector pane). Is there another way?
Maybe "refnum", but I don't really understand how to use them...
If I use the event structure in the main vi, the wafer map is still not working. I tried it earlier.
To implement the multi tab front panel, I used a tab control, and a for loop + case structure. For each element of the case structure, there is a corresponding action.
For the case where I put the code (element=2) for Wafer Map, I also control the execution of the code with a case structure activated by the button "REFRESH". Otherwise I end up with a freezing of the panel right after the start.
I hope these comments help you understand better.
Regards,
Florian
Attachments:
Control Interface.zip ‏104 KB

Event structure problem in updating array

Hi, i have a problem with my .vi...
i have an array of 10 boolean i want to modify by pressing SET TRUE or SET FALSE buttons, after selecting (with the ring selector) which is the elemente that should be changed...
there seems to be something strange in the behaviour... the array is not correctly updated... maybe there a big mistake i cannot find...
i hope you could help me
tks
Attachments:
array_modify.vi ‏18 KB

The problem is the the Ring control is read before the event structure, so it return "old" data when you click of either SET TRUE or SET FALSE.
You need to move it so that it is read inside the event structure after you click on one of the "SET" buttons.
Create a local of the Ring for one of the SET events and move the Ring terminal into the other.
Or create a blank event for the Ring control so that it will update the input tunnel going into the event structure.
Or create a single event to handle both SET TRUE and SET FALSE.
Omar
Attachments:
array_modify.vi ‏9 KB

How can I set up my Mac Pro so that my wife and I can use our separate iTunes accounts? I keep getting an error message that the computer is already associated with an Apple ID even though the two accounts are associated with separate log ins!

I'm getting very confused with setting up multiple user accounts on my Mac Pro for my wife and I. We each have a separate iTunes account, and we want to keep our music libraries seaprate. I've set up two user accounts on the Mac Pro and I have my iTunes authorised and logged into my user account on my user account. Under my wifes user account (i.e. a separate log in on the computer) I'm trying to set up her iTunes account, but I can't download or play anything from the cloud - it just says "This computer is already associated with another iTunes Account" and tells me that if I 'transfer' then I won't be able to use the other one for 90 days! This is really annoying as my wife can't access music she has purchased on her iTunes account on the home machine. We're not trying to do anything dodgy, just access our music on our own accounts on separate log ins on the same machine. Does anyone have any suggestions? Thanks!

Hi Allan, thanks for that. I've already set up a log in for my wife and that is all working fine. The problem is that when she logs in and opens iTunes and trys to associate her library with her iTunes account she gets the error message "This computer is already associated with another iTunes account". Whilst this is true, the computer is associated with my iTunes account under my separate log in, which should have nothing to do with hers. If she transfers the association to her account it will lock me out of my content on my log in for 90 days - I'm trying to work out how to associate each of the log in accounts with a separate iTunes account so we can access our music independently of one another without locking each other out. Hope that makes sense!

Successive run - Event Structure

Hello...
I have a simple question. Sometimes we want to use Event Structure and put only a piece of the code in each case. The problem is that a case might have only math code, without any control, indicator or array. Because of this, this case will not have any "thing" that can trigger its execution.
To avoid this and allow me to control in arbitrary form the execution of the cases, I created a simple code where I can specify which case will be runned after a especific case.
Attached there is a example just to show how it works.
My question, is there a better way to do this?. I mean, specify that after one specific case runs, another specific case will run.
Thanks in advance.
Dan07
Attachments:
Event Structure Run.vi ‏30 KB

There are various problems with trying to use the event structure itself to be the case selector for a state machine:
You can't guarantee that cases will execute in a particular order, because other registered events could fire during a sequence and interrupt the intended chain of events. For instance, if a user presses a button while the event structure is in a sequence where it triggers itself repeatedly.
It takes a lot of effort to create these hidden controls that only exist to fire value change events. And it makes the code confusing because they serve no real purpose. Yes, User Events are the preferred solution to this problem, even if they require more wiring and control, but they don't solve the first problem in the list.
A better solution might be something along the lines of a Queued State Machine architecture. It's a mix inside one loop of an event structure and an outer case structure. It's a little difficult to explain in words, but there's a good template free to download from JKISoftware that also has a tutorial video about it that you can learn more about here. I've recommended this before, but I promise I don't work for them or anything It's just good technology and a lot of thought has gone into it. JKI didn't invent the paradigm, but they've implemented it pretty it well.
It seems to solve a lot of the problems you have. It allows for user interaction through the event structure, and it allows you to trigger a sequence of cases not related to controls or indicators that have events registered for them. And it solves the two problems listed above. The architecture is inherintly self-documenting and clear, and it avoids the pitfall of allowing user interaction to unintendedly interrupt import sequences of events. The downside is that it's not the simplest of architectures, but it's also not the most complex. Check it out!
Jarrod S.
National Instruments

Event structure inside a case structure

Hi,
I've got a problem w/ my porgram, and managed to boil it down to this
simple example. The program basically hangs if you change the
Numeric value when the boolean is false. I don't understand
why. I suspect it has to do with the way event structures are
treated, but if someone cou please explain this I'd be greatful.
Also, now imagine I have 7 numeric controls, handled by 7 cases in that
event structure, and I actually want to do things in response to the
value change for each. Can someone suggest an elegant way to do
that? I thought what I had here was a good design, but apparently
not.
Bjorn
(I'm using labview 7.1)
Attachments:
EventInCase.vi ‏24 KB

It is generally a bad idea to place event structures into cases. Events structures need to be able to breathe.
Maybe you can redesign your program and place the case structure inside the event structure, for example? (Also have a look at the online help for the event structure, especially the link "caveats and recommendations for using events ".)
Detailed analysis:
Your event case for the numeric is set to "lock front panel until event completes". If you change the numeric while the case is false, the evet structure cannot execute, so the front panel locks forever. The observed behavior is as expected. All clear?
In addition, if the case is false, the main loop spins at nearly infinite rate, consuming all available CPU. Place a small wait to be more cosiderate to everything else running on your rig.
LabVIEW Champion . Do more with less code and in less time .

Event structure and waveform graph cursor

I am utilizing a waveform graph and I need to programatically manipulate multiple cursors based upon the movement of a primary cursor. I would like to use the event structure to avoid processor usesage.
My approach is to create an While Loop/event structure where it goes into a it when there is a "mouse down" on the waveform graph. Once in it, there is another While Loop/event structure that has two cases: Time Out (set to 25) and a "Mouse Up" on the waveform graph. In the Time Out case, the primary cursor is read and modifies the location of the secondary cursors. In the "Mouse Up" case, the primary cursor location is read, other cursors are manipulated, and the While Loop is exited.
When I code this up and perform a "mouse down" on the waveform graph, the index on the inner While Loop/Event Structure is advancing but there is no control (can't move it) of the primary cursor on the waveform graph. When I "Mouse Up", the inner While Loop exits.
Obviously, my approach is flawed here based on my lack of understanding of the characteristics of the waveform graph and cursor manipulation. Has somebody come up with a way to achieve what I am trying to do?

This is basically the method I typically used in LabVIEW 7.1 and below as described in this old post.
Of course you could upgrade to LabVIEW 8.0 and none of this is necessary! LabVIEW 8.0 has events for "Cursor Move".
Now you only need the "cursor move" and "stop" cases. Isn't that cool!
Message Edited by altenbach on 12-12-2005 07:05 AM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
LV8CursorMove.png ‏6 KB

No more than 2 event structure?

I don't anderstand how can I do my programm because I read that we must not use 2 events structures in one loop. But concerning my programms for instance I have to fill arrays only when I press each appropriate "Ok" button (for instance for 5 case I have to press 5 different OK button ) and so on (when I press OK number 6 the program write to excel program.. when I press OK number 7.. )
How can I do it? I need to create 7 events structures for 7 actions?
labview 7.0

When they say not to use two event structures in one loop they are refering to the number of actual "event structures" that are dropped on to the diagram, not the number of events that one structure can handle. You could have "an event" configured for each of your "ok" buttons, and then have those events, when triggered, select a different case of a case structure, possibly on the "timeout" event. If you built it like that, make sure to have a timeout value wired to the upper left corner, or it will default to -1 (never timeout).
Here is a very simple example of one way to implement it.
Putnam
Certified LabVIEW Developer
Senior Test Engineer
Currently using LV 6.1-LabVIEW 2012, RT8.5
LabVIEW Champion
Attachments:
simple event.vi ‏36 KB

Load defaults from file with event structure in vi

Hi All,
I've been trying to figure out how to do this but have not quite got there. Taken a look at lots of posts but can't quite find the answer to the question that i've got.
I've got a vi for controling 4 PCI cards making calls to some DLL's. I've got quite a number of controls on the FP and i use an event structure to update the values on calls to the DLL. On startup, one of the first calls that i make is initalise and that sets the cards up. I then want to load my own set of default values from a file to initalise the cards to my particular set up. While the software is running the user may change the values and wish to save a file with the new default values, or he may wish to load a different file of default values (depending on the test that he is running). I've got the Control Values:Get All [variant] and the Control Valueset [Variant] working to save all the controls values to a file and read that file in and set all the controls values. So far so good. Problem is i'm using an Event Stucture and it doesn't register that the values have changed. I could complish this by using Value(signaling) but the data from the Control Values:Get All is variant data and the Value(signaling) needs the same data type as the control. What do i do?
One thing i have thought about is to write all the values from the file to all the conrols and then have a read Value and a write Value (signaling) to trigger the events. Problem is i don't want to set this up for every control (it'll take me ages). Can i do it programitically? Is there a better way to do it?
Thanks,
Phil

You could create a boolean control/indicator and signal that value when you've updated the values on the FP.
Name it something like "update FP". The event case for that boolean will have the code to update the necessary parts of the FP.
André
Regards,
André
Using whatever version of LV the customer requires. (LV5.1-LV2012) (www.carya.nl)

How to use a event structure with a state machine

First, I would like to inform you that I only work on LabView part time, and have much to learn. Anything I do learn, I usually forget until I need it again, because I only work on it part time.
Using your StopWhileLoopMOD[1].vi, I am trying to put a state machine inside the event structure.
Related link: http://forums.ni.com/t5/LabVIEW/How-to-stop-while-loop-in-Event-case/td-p/465564/page/2
Here is my application: on the front panel, the user can select any combination of 7 different tests. I have created cases to perform each step of each test in the correct order, but if the user presses stop, the tests won't stop because some of the cases have a while loop inside the event structure (like you mentioned is a bad idea). The user should be able to stop the test, reselect tests to perform, and re-start the tests.
When the start button is pressed for the event structure, I need all the cases to run in the proper order, unless stop is pressed.
In the past I have indexed an array and used that to run the state machine, but it won't stop immediately.
I have sub VIs that are built in while loops because the outputs of the product needs time to stabilize.  The state machine stops and waits up to a certain number of iterations. If it passes the test, the while loop stops and the next state starts. If it takes too long, it exits and reports an error. Maybe I need to just use the state machine and not an event structure?
Is there a good example of an event structure?
metzler CLAD
Solved!
Go to Solution.

I'm not sure exactly what you are asking, but it sounds like you want to script a bunch of tests and if the user says stop, to immediately stop the current test and abandon the others? I'm going to assume that you know how to clear the array so that it will abandon the others, so I'm guessing that you are having trouble abandoning the current test? If this is indeed the case, then the problem is that you are not able to propagate the message from the main VI FP which is the GUI to the sub vi which is the test, where the test may or may not have a GUI (FP visible) of it's own. Threading was the first thing to come to mind, but this may not be necessary using events.
You can do this by passing a refnum of the stop button to the subVI, where you can then add that wait to the event case structure.
I've attached 2 VIs, mainvi.vi which is just a loop displays the count*2 (number of seconds passed since running) that will call subvi.vi and then check to see if the stop button is pressed. mainvi.vi is by no means a state engine, it is just a simple loop for demonstration purposes. subvi.vi just waits 2 seconds and leaves, it is a better structured state engine with an init state to start a poll case to wait for events and an exit state to clean up. You can modify this any way you wish to get it to do what you want. You will note that even if subvi.vi is being executed, it will terminate immediately when the stop button is pressed.
Hope this helps.
A
Attachments:
mainvi.vi ‏17 KB
subvi.vi ‏33 KB

Using Event Structures with Array of Clusters

Using LabVIEW 8.5
Hi all,
I'm trying to convert an existing application to one that can be used
through a touch screen. I updated the UI and added an event structure
to listen for mouse ups on controls that require a HMI keyboard or
numpad to show up. Although I've been programming for a while, I'm new
to LabVIEW and am struggling with a problem:
Is there any way to have an event case listen to an event within
arrays? I've seen a few examples on the forums, but they all start with
breaking up the arrays into individual variables. Using the variables,
they build arrays. This seems pretty tedious, and I'm pretty sure I
can't apply it to one of my arrays. Essentially, I just want to know
which cluster in which array the user has clicked on, so I can open the
HMI keyboard or numpad and send the text to that cluster. In my watered down app (Array of Clusters.vi), I've put 3 arrays of clusters and a few stand-alone controls to give you guys an idea of what I'm taking about.
BTW, I'm using the HMI Keyboard and Numpad built by the Beta Community (http://decibel.ni.com/content/docs/DOC-1062) and modified it to add a "Clear" button to the keyboard and numpad. Please let me know if I implemented this in the best way.
Thanks for the help,
Kunal
Message Edited by bhatiak on 08-04-2008 03:55 PM
Attachments:
Array of Clusters4.llb ‏274 KB

My old tic tac toe example shows how to determine which square of a 2D array has been clicked.
http://forums.ni.com/ni/board/message?board.id=170&view=by_date_ascending&message.id=247044#M247044
You probably can adapt some of it for the arrays on the right. If the array can be scrolled, you also need to account for the "indexvals" offset.
The Layers controls is easiest, because you only show one element. Just read the "index vals" property to get the array element and parse the coordinates to get the cluster element.
btw: the small while loop on the right serves no purpose at all and acts just as a CPU burner. You can delete it without any change in functionality. Is there anything else to it?
LabVIEW Champion . Do more with less code and in less time .

Can I have multiple event structures with the same event cases?

Hello,
I'm doing an application that reproduces the front panel of the HP6675A power supply. To achieve this, I have done a state machine with different states
(initialize, measures, voltage, current, ocp, ov, store, recall, etc). In each state, should have an event structure that catches the events of the buttons, like for example: if the current state is the Voltage mode and the user press the current button the next state will be the Current mode. For this in each state of the state machine should be the same event structure with the same events.
My problem is that the Vi doesn't work properly when I have multiple event structures with the same event cases. There are some possibily to do this, and how? Or is impossible to have multiple events? I have been reading some posts, but I don't find solutions.
Any help is appreciated.
Thank you very much.
Solved!
Go to Solution.

natasftw wrote:
Or as others mentioned, make two parallel loops. In one loop, have your state machine. In the other, have just the Event Handler. Pass the events from the handler to the state machine by way of queues.
A proper state machine will not need the second loop. The "Wait For Event" or "Idle" state (whatever you want to call it) is all you really need in order to catch the user button presses. The setup is almost there. Maybe add a shift register to keep track of which state to go to in the case of a timeout on the Event Structure.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines

How to stop While Loop in Event Structure with same button?

Hello,
I have a problem. I want to use one control to activate an event in a event structure, and the same control to terminate a while loop in that event.
It is possible to use 2 controls to do this, but I need it to be only one.
Thank you
Message Edited by Heinen on 02-19-2009 06:16 AM
Message Edited by Heinen on 02-19-2009 06:20 AM
The Enrichment Center is required to remind you that you will be baked, and then there will be cake.
Solved!
Go to Solution.

Hello,
I have a bit different problem.
I have a tab control, with several buttons on different pages.
In the current situation, we can talk about two pages, where one page ("Settings") in the Image, has a START and EXIT button, while second page ("Wait") has an EXIT button.
In a while loop, I have event structure, which handles events of the START and EXIT buttons of the Settings page. This is fine. But I also want to control the Exit button of the Wait page.
The control works like this:
When I click on Start in the Settings page, the front panel shows Wait page and attempts to connect to a datasocket server on the remote computer. If the user wants to stop this process, he can click on Exit on Wait page too. But, this doesn't give any immediate effect. On the even of Start button, the front panel is not locked, so the user can actually click the Exit button on the next page when it's visible. But it's of no immediate effect. Means, what the LabVIEW does is, finishes the execution of event in Start button's click, and while this executes, it doesn't consider the Exit button's refreshed value (shown in Red circle in the block diagram).
Simple question: Is there any way to check the updated (latest/live) value of a control during some event's execution? Or if I write an Event "Value Changed" for the Exit button and pass it to some variable. Is it the only solution?
Thanks ahead.
Vaibhav
Attachments:
terminate event_diagram.jpg ‏200 KB
terminate event_front_1.jpg ‏63 KB
terminate event_front_2.jpg ‏63 KB

I need help with event structure. I am trying to feed the index of the array, the index can vary from 0 to 7. Based on the logic ouput of a comparison, the index buffer should increment ?

I need help with event structure.
I am trying to feed the index of the array, the index number can vary from 0 to 7.
Based on the logic ouput of a comparison, the index buffer should increment
or decrement every time the output of comparsion changes(event change). I guess I need to use event structure?
(My event code doesn't execute when there is an event at its input /comparator changes its boolean state.
Anyone coded on similar lines? Any ideas appreciated.
Thanks in advance!

You don't need an Event Structure, a simple State Machine would be more appropriate.
There are many examples of State Machines within this forum.
RayR

Calling a VI in a subpanel with parameters inside an event structure and using an abort button

Hi all,
I have a control panel with a tab control and two tabs have a sub panel in them. At runtime I load the VIs I want in to the sub panels. In the control panel event structure I want to start each of the VIs and monitor the execution state so I can abort the VI while it is running. One method I use can run the VI and the abort event will work (see example). The second method I use does not and this is what I want to do! I have many inputs to the VI I want to pass so placing the VI in the event blocks everything else and it has to wait until the VI has completed, so I cannot monitor the execution state.
I have attached an example of what I want to do.
Any help appreciated.
Martin
Solved!
Go to Solution.
Attachments:
SubPanel.lvlib ‏2 KB

Hello,
You can do this with queues.
The main vi and subpanel vi's should be based on the producer/consumer (events) and you handle the front panel events accordingly in the respective vi's.
Name the queues in obtain queue , for example the Main being MainQ, subpanels SubPanel1Q, SubPanel2Q. When you start the application, initialise the main vi and also run both of the subpanels (just to make sure that the queues are first obtained by themselves). Then you can use obtain queues to do inter vi communication.
For example if you need to send data from main to subpanel1, use obtain queue and use the name SubPanel1Q, pass the required data & command and voila. Subpanel1 vi will receive your message. You can do this anyway you want. Hope this helps.
Beginner? Try LabVIEW Basics
Sharing bits of code? Try Snippets or LAVA Code Capture Tool
Have you tried Quick Drop?, Visit QD Community.

Stuck with making my event structure examine if two arrays are equal

Similar Messages

Maybe you are looking for