FPGA event Structure

Hi,
Iam working on DC motor...... iam using NI 9505....... iam using example code of labview {(Position Control (closed loop)- under compact RIO}......
every thing is fine............ now i want to add control LEDs which has to control the speed of the motor......every led represents some values......there are 66 leds.... i thought i can use event structure so that when ever an event(boolean led ) occurs that event will suplly the value of posotion setpoint to motor.........
i have added event outsde, inside, with, without while loop...evry thing i tried.......but iam not getting......i wan to know where iam doing wrong..... to understand better i have attached two images front panel and block diagram......
please help me out of this problem...........
Attachments:
front panel.jpg ‏325 KB
block diagram1.jpg ‏269 KB
block diagram 2.jpg ‏233 KB

HI,
Here are the Complete Detials.........
1> position setpoint is not an indicator........ its a control
2> for one rotation of motor is 360 degree---- now i want to rotate motor for 360 degree in 66 times...... and i want to indicate the value....... so i divided 360 by 66 which is 5.45......
3> Now i calculated the motor ratio........ digitaly to rotate motor, it requires 1230.5 which is position set point..........
to rotate motor at 0 degree we need position set point at 0
to rotate motor at 360 degree we need position set point at 1230.5
4> i implemented this logic outside using 4 LEDs and its values is given( please go through 360 degree implement.vi)
5> i want to implement the same logic in this positon control (closed loop).vi
but its not taking the event strucutre.......
6> i have attached the vi....... there will broken wires since there is no fpga target..........
7> i have attached compelte source code for position control project........ here in this project i want to add 66 leds which will control the motor for one rotation with respect
above steps
Please let me know if u need any more info on this.......please go through above snap shots for inserting the LED structure....
Thank you
Attachments:
360 degree implement.vi ‏26 KB
Position Control.vi ‏205 KB
Position Control.zip ‏517 KB

Similar Messages

Event structure doesn't register local vars

I have a gif of a basic FPGA topology that I want to show some loopbacks in. As the user clicks on the booleans, vertical lines should appear, then disappear as they click them again, showing the current loopback topology.
To conserve resources, I opted to use an event structure. So far I have set it up for the RX_FAC and RX_TERMXCO4AU loopbacks that you see in the upper left of the picture.
Only one RX loopback and one TX loopback can be on at a time, so one of the first things that happens when the user clicks the boolean is that it sets the values of all the other booleans in that row to false, via the use of local variables.
The problem is - the event structure only executes when the user actually clicks the boolean true or false, but not if the boolean is set false via the use of a local var. In other words, let's say I have RX_TERMXCO4AU true, and RX_FAC false. If I click RX_FAC to set it true, then you'll notice RX_TERMXCO4AU goes dark/false, and RX_FAC lights up. So the value of RX_TERMXCO4AU changed, but the event structure associated with RX_TERMXCO4AU did not execute (which is why the vertical line between RX_TERMXCO4AU and TX_FACXCO4AU stays there).
This will make a lot more sense if you run the attached simple VI. Right now, events only exist for RX_FAC and RX_TERMXCO4AU, but it's sufficient to explain the problem I think.
Any help is appreciated.
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Attachments:
loopbacks.vi ‏55 KB

bmishoe wrote:
I learned something new today...
One more thing you can learn, When you are passing an array input to a For loop with 'Auto indexing' enabled, you need not wire anything to For loop's 'N' terminal.
In other words:
If you enable auto-indexing on an array wired to a For Loop, LabVIEW sets the count terminal so you do not need to wire the count terminal.
In your code, you can remove the 'Array Size' nodes.
I am not allergic to Kudos, in fact I love Kudos.
Make your LabVIEW experience more CONVENIENT.

VI containing Event Structure will not receive front panel events in LabVIEW Real-Time.

Hi again, I'm working in my first UI (attached VI).
It works when running directly from PC. It doesn't when running from cRIO, there's the message "VI containing Event Structure will not receive front panel events in LabVIEW Real-Time". I've been reading and I found that "Event structures on RT targets do not support events associated with user interface objects, such as VI panels or controls. For example, associating the Value Change event with a control does not work. RT targets support only user events".
Is that the problem? If it is, how can I create Mouse Up, Mouse Enter, Value Change (or other user interface events) user events?
If I run my VI in FPGA mode should it run?
Attachments:
HMI.vi ‏33 KB

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
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
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Event Structure in Timed Loop in real time cannot work

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.
However, this works very good in my computer (without connect to FPGA).
Once I connect it to FPGA, then I can run it still but there is no response!
My file is attached. Please somebody helps me!
Looking forward to your answers!
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Attachments:
Test for Timed Loop.vi ‏9 KB

The FPGA runs headless. Event structures are not going to work. What you need to do is have an application on your host where the user presses a button, changes a value, etc. That event should send a message via TCP/IP to the code running in the real time environment. Then the real time environment should set a control on the FPGA to the value you want.
In general, real time programming with FPGA has multiple layers.
1) Host code-> handles user interactions and communicates them to real time code via TCP,UDP, etc. Displays data to user sent from the RT controller.
2) Real time code->runs headlessly. Handles messages from Host code, processes FPGA data, communicates with FPGA much like the host code communicates with the real time code
3) FPGA -> does acquistion and passes it via FIFO to the RT
The first thing you need to do is understand the architecture and how all these pieces of the puzzle work together before throwing things down on a diagram.
CLA, LabVIEW Versions 2010-2013

Can you share FP Controls between different Event Structures

I'm creating a program that will either read real-time data from an VNA on the GPIB bus, or read a saved s2p (Agilent) file and analyze it. The FP consists of 5 graphs, and various controls which handle events like printing, changing filters, or exiting. on the BD I have a case structure controlled by an operator selection pop-up. I tried using the same FP controls in the event structures I have setup in each case, as only one event structure would ever be executing at any given time, but the program doesn't seem to like it ast run-time. I've worked around the issue by creating "duplicate" controls and using the property setting to make them visible/disabled, etc., but the is seriously congesting my BD.
Anyone know a way to share controls with seperate event structures?

It sounds like the root problem is the overall structure of your program. I highly recommend that you check out the Queued Message Handler project template in LabVIEW 2012, that will show you how to utilize a single event structure and pass events to a consumer loop. If you program is too large to consider an architecture change at this stage of the game, then there is a workaround for your problem.
What is most likely happening is that you have the event structures all set to lock the front panel until the event completes. However the case structure that you have wrapped around these event structures is causing all but one of these event structures to be unreachable thus preventing you from handling the event. Again, as I stated above, the "RIGHT WAY" to fix this is to select a better program structure but the "kluge work-around" fix is this: Dynamically register for the value change event on all of the controls you are trying to trap events for. Dynamic events can be deregistered and re-registered at run time. This will allow only the event structure in the active owning case structure to be registered for the events, thus no other event structures will get in your way.
Disclaimer: This advice is given based on very minimal information and a great deal of speculation and may not be correct. Please include your code if you need further assistance.
Charles Chickering
Architecture is art with rules.
...and the rules are more like guidelines

Daqmx "Done" event not triggering event structure

I would like the user to be able to abort my daqmx task by pressing a button.
I am attempting to use the method in this VI:
https://decibel.ni.com/content/docs/DOC-15815
It utilizes an event structure with the daqmx Control Task VI to abort.
The example VI above works for me, on my system with my USB-6356 device, as expected.
When I attempt to incorporate the same method into my VI it does not--despite having an identical arrangement, so far as I can tell.
I believe that my problem lies with the event structure, and the dynamic registration. I am unfamiliar with this and must be using it incorrectly.
I have attached my VI, though it is cumbersome. The code which I am struggling with is in the "Acquire" case. As far as I can tell, I am doing exactly the same this in this particular case as in the example mentioned. Yet in the example, the event structure completes, or aborts, whatever you want to call it, right after the "Wait Until Done" VI executes. In my own VI, the "Wait Until Done" and "Clear Task" VIs execute, but the event structure does not register it.
Here are my specific questions: is there anything extra or special that one must do in order for the Task to properly trigger a "Done" event and pass through the event structure? At what point is the daqmx task "Done"?
thanks,
Matt
Attachments:
BoomTubeMain.vi ‏175 KB

natasftw,
My event structure is identical to theirs; what you are seeing are the two different cases that exist in the event structure. In both the example and the VI, there is a <task out>: Done and a "Dynamic Event": Value Change. In the dynamic event case, I have my abort button and relevant code--this I believe is the code you were referring to, which you thought I was missing... Regarding my multiple event structures, they should operate completely independently as they respond to different events.

Stop execution of a loop in an event structure

I tried searching the forums to avoid posting a duplicate, but most I could not open most of the vi's as they were higher version.
I put in a dummy while loop in an event structire i intend to use. Once I start executing the while loop, I am not able to stop it using a control for some reason from the fornt panel control.
I am not able to change the vale of the Stop control at all. I tried creating a seperate event for STOP, and I still could not stop the program when the While loop was executing.
I imagine I am missing something really small. I would appreciate your feedback on this.
Thanks,
Nevil
Solved!
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Attachments:
FrontPanel.vi ‏34 KB

Right click on the event structure and choose "Edit Events" for the case that is giving you trouble.
Be sure the checkbox to lock the front panel is unchecked.
I suspect yours is checked, so your front panel is locked out until the event completes, thus you can never stop your loop.

Event structure in Sub VI

Hello ,
I have a developed a program which captures video and user can save images out of it. I have used .NET reference to handle the video part, and the VI is attached in this post. Now i have to make this VI as a sub VI and running this from Main VI. I tried creating event structure in Main VI which i used in sub VI , still i could not suceed. Kindly assist me in this regard
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Attachments:
Webcam-Control-Projekt-mit-Reference-Design-2013_original.zip ‏286 KB

Hello Michael,
I have attached a model in which Main VI calls the Sub VI using Event Structure. Two events can occur in Main VI and their corresponding event Structure is called in Sub VI using Register events. When i run this VI the out put is fine some times but other times i need to trigger event many times before i can see its effect in Sub VI, my doubt is that Register events are reliable, whenever (during the execution of LV) if event occurs will surely its code in the sub Vi gets executed?
also I have put a indictor(numeric) in the SUb VI which i connect back to Main VI, when i run, i can see the result only in the sub VI not in the main VI.how to see in Main VI?
I have used the this model (which is attached ) to implement my project(which i already mentioned) . one switch for starting the video and other for recording the image. The video is getting started with out any trouble, but imgae is recorded only few times when i press the button which is for image recording, most of the time second event fails to get executed. Also there are difference in output when i run with and without "Highlight execution", why this happens, is this because of Reg events?
any more info if required let me know, i will provide.
Attachments:
Main_sub_VI.zip ‏18 KB

How to make Vi file as input file in Event structure?

Hiii All..
i got problems when to construct a event structure. The file input (vi format) doesnt have source of wire connection to conect the wire (shift register) .For your information the vi that i create only contain simple mathematical equation.
I already study the New Event Handler Example. but the file input for that example (acquire data.vi) have a source of connection. anyone can help me?
thank you very much
[email protected]
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Attachments:
TOTAL.vi ‏18 KB

Well, in your subVI you do need to wire up some inputs and outputs to your connector panel. As I said, a basic LabVIEW skill that you will find in the tutorials.
You have a number of inputs to your subVI. More than you would want to attach to a connector panel. You should perhaps use a cluster to group them together.
To get you started, here are the steps to connect a control or indicator to the connector panel.
1. Open subVI.
2. Right click on icon at upper right. Show Connector.
3. Hover over a block you want to be a connector terminal, it will change to a spool of wire. Click.
4. Go to the control or indicator on the front panel that you want to associate it with. Click again.
5. Repeat as needed for other controls and indicators and save your subVI. Now the subVI instance in your main VI can have wires connected to it.
You should plan your connector panel so that controls are on the left side of the panel, and indicators on the right. This will allow data to "flow into" and "flow out of" the subVI in a normal looking left to right orientation.

Event Structure Freezes Vi After Capturing The First Event

My Event structure catches the first instance of my button press but then it freezes my Vi. The reason is because of the while loop but I need the while loop to constantly read from a serial port and send data to a serial port. The vi included is stripped down to be just a while loop that does nothing. I have also tryed putting the event structure in the while loop, but the same thing is happening.
Any ideas?
Thanks,
Cason Clagg
SwRI
LabView 7.1, Windows XP

Also, put the button inside the event structure where it is acted upon, from LV help (suggest you read the entire events section of help):
When you trigger an event on a Boolean control configured with a latching mechanical action, the Boolean control does not reset to its default value until the block diagram reads the terminal on the Boolean control. You must read the terminal inside the event case for the mechanical action to work correctly. As a reminder, a note appears in the Edit Events dialog box when you configure a Value Change event on a latched Boolean control.
Refer to the Handling a Latched Stop Boolean Control in an Event Structure caveat for information about how to handle a latched Boolean control.
When you trigger an event on a Boolean control configured with a latching mechanical action, the Boolean control does not reset to its default value until the block diagram reads the terminal on the Boolean control. You must read the terminal inside the event case for the mechanical action to work correctly. As a reminder, a note appears in the Edit Events dialog box when you configure a Value Change event on a latched Boolean control.
Refer to the Handling a Latched Stop Boolean Control in an Event Structure caveat for information about how to handle a latched Boolean control.
~~~~~~~~~~~~~~~~~~~~~~~~~~
"It’s the questions that drive us.”
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How can i use the same front panel graph in more than one events in an event structure?

i want to display the signals from my sensorDAQ in a graph.but i have more than one event in the event structure to acquire the signal and display it in the graph.the first event is to acquire the threshold signals and its displayed in the graph as a feedback.after the first event is executed, i will call the second event,where the further signals are acuired and compared with the threshold signals from the event 1.my question is how can i use the same front panel control in more than two events in the event structure?please answer me i'm stuck.
Solved!
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Hi,
I have attached here an example of doing the same using shift registers and local variables. Take a look. Shift register is always a better option than local variables.
Regards,
Nitzz
(Give kudos to good answers, Mark it as a solution if your problem is Solved)
Attachments:
Graph and shift registers.vi ‏12 KB
graph and local variables.vi ‏12 KB

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!
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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

How to use an Event Structure responding to an image control that belongs to a parent VI.

Hi
I am loading a subpanel vi by pressing a button located in the user interface of the main vi which also contains an image display. Subpanel vi opens up on the side and doesn't hide the image display of the main vi. Subpanel vi contains an event structure that needs to respond to user clicking on the image display of main vi.
Since the bug that occured while creating an image reference control isn't fixed, I am passing the main vi pane reference onto the subpanel vi. From that point I've tried to edit event structure and have it respond to the image control/pane that belongs to main vi but I don't know how.
Any help would be appreciated.
Thanks

Post a screenshot of your subVI code where you register the events.
André
Regards,
André
Using whatever version of LV the customer requires. (LV5.1-LV2012) (www.carya.nl)

Event structures used to monitor indicator change

I am new to the event structure.
Is it possible to monitor an indicator for a value change? I know this works with controls, but I'm not sure you can monitor and indicator in this way.
Thanks,
-Nathan

Yes, it's possible. However, in order to change the value so that an event will fire, you'll have to use the value(signalling) property of the indicator. It won't work if you simply wire a value to it.

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 .

FPGA event Structure

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