Combine 4 stops for 4 case structure

Hello everyone!!
I meet a problem in my project, I knwo it's not difficult but we are all beginners for labview.
We need to control 4 batteries, each battery needs a life cycle calculator. I try to connect 4 life cycle calculator(case structure) in my while loop, but there are 4 stops for 4 case structure and 1 stop button for the whole while loop....I don't know how to handle with these four extra case structure stop buttons....
As the battery charging and discharging, the life cycle part keep working so actually it's no need for stop button for each case structure , can we just get rid off the stop button for each case structure?? Is there any problem with the life cycle calculator if we do not use the stop button???
Really Thank you for help !!!!
here I attach our vi, you can configure it directly !!
Attachments:
PR2.vi ‏78 KB

The main problem is code architecture. Once you fix this, your current problem will vanish automatically.
You seem to be spending way too much time rewriting basically the same code over and over. You need to modularize the code and make it scalable. You have four instances of basically the same code. Are you planning to later scale this up for a few hiundred batteries? Would you then simply make it a diagram that is millions of pixels hight? Once you combine all the functionality for one battery into scalable code, you can scale it up for an arbitrary number of instances.
Same for the front panel. Make the controls for one battery into a cluster and then make a 2D array of such cluster (2x2 in your case). Suddenly, the entire code will be the size of a postage stamp and easy to maintain. If you currently want to change an error in the algorithm, you need to make identical changes in four different places. If you forget one place, bugs will be very had to find.
LabVIEW Champion . Do more with less code and in less time .

Similar Messages

Multiple booleans controlling one boolean input for a case structure

Hello,
I have four boolean buttons and a case structure with a boolean input. I would like to write the program so that whenever any one of the four boolean button changes value, the case structure reads true for one loop interation, and then returns to false.
I have tried all sorts of things and can't seem to figure it out.
Ultimately, the ideal function of the program is so that whenever you push any one of the four boolean voltage controllers, that voltage case is chosen in the case structure, the time in seconds is written to a file, and the elapsed time timer is reset.
I have attached my program. Let me know if you have suggestions. Thanks.
Attachments:
Volt_Control_And_Time_Counter.vi ‏71 KB

Zappow wrote:
However, with this setup, the time counter still doesn't work.
The event structure for all four buttons has a true boolean constant connected to my file-saving case structure. If I connect this to my elapsed time express VI reset button, the timer doesn't count.
The timer does not count because you have not wired a timeout to the lower event structure. The default timeout is -1, so the lower loop never spins via timeout
It is useless to have a wait in a loop that also has a timeout case. Just wire an approriate timeout value to the timeout terminal and remove all waits. It is also not necessary to have a 1ms ttimeout if your timeout values only displays to 100ms resolution. Can you explain why you think you need two loops and all that extra code?
Attached is a quick rewrite that solves some of the problem. Since I don't have any hardware, I replace the voltage out with a meter.
You have way too many FP controls and indicators. Use arrays!
Let me know if yo have any questions. Modify as needed.
LabVIEW Champion . Do more with less code and in less time .
Attachments:
Volt_Control_And_Time_CounterMOD.vi ‏63 KB

Can I put a READ function in a TRUE/FALSE case structure?

Hi,
I have a vi that operates as controller for a mechanical system of motors. There are several sensors of various types, that provide input to the vi, including encoders, whose period is being measured. The attached vi is the encoder period measuring part. It measures 15 periods and tells me the average of the 15 with each loop iteration.
In my application, the encoder period measurement is not needed unless the vi knows that ALL THE OTHER sensors in the hardware configuration are measuring values within the desired range. For example, Sensors A, B and C should all measure between 5-10. If they are all showing values between 5-10, then, we want the encoder value to read and display. If only one of the sensors, say A, is measuring 12, then, we don't want the period value to READ or be subsequently processed. So, it is easy to set up the sensors A, B, C, to give a TRUE or FALSE based on whether they are within range or not, and if all 3 are TRUE, then, that value can easily be passed to the case structure that holds my READ function for the period. Is this a good way to do this? The goal is to eliminate unnecessary execution time that the period READ function would consume, as well as all subsequent calculations that are performed on the period value collected. The period data is of no use if any one of the other sensors is not in the correct range.
If any one of the other sensors is out of range, we want to skip the encoder READ step altogether. So, it is easy to structure a BOOLEAN in my vi as shown in the attachment. If I do it this way, will it throw an error, or just skip the READ until the BOOLEAN is true again? Is there a better way to prevent the READ from happening if one of my other sensor values is not within the correct range?
Thanks,
Dave
Solved!
Go to Solution.
Attachments:
forum JUly 18.vi ‏26 KB

Sure, you can put a Read inside a case structure. For your application, just check that your sensors are all within range (Comparisons palette), then AND the T/F's and use the result of that for your case structure. (If you are already doing the in-range check, I can't see it here because you have 5 subVIs that I cannot open here.
Cameron
To err is human, but to really foul it up requires a computer.
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Cases programmatically from xml in case structure

I want the cases in my case structure to be updated programmatically from an xml file. Is this possible?

You can, but don't forget what Felix wrote - a VI can't programmatically change itself. You'll need a separate VI to modify the Case Structure you're working with.
This example gets a reference to the target VI, traverses for all Case Structures, selects the target by its label, adds a frame and gives it a Selector Label. You'll need to modify the last three VI Server nodes to accommodate your particular application.
Good luck.
<edit> take a look at my CaseSelect JKI RCF Plugin, it contains a bunch of Case Structure manipulation code.</edit>
Jim
You're entirely bonkers. But I'll tell you a secret. All the best people are. ~ Alice
Attachments:
contains case structure.vi ‏9 KB
controls case structure.vi ‏12 KB

Programatically get the states of case structure

Dear all,
Is there a way we can programatically get all the states of a case structure in my VI.
I know that there is no property node for case structure, but I am sure there must be some way that labview ppl must have thought about it.
Awaiting....
cheers
Sree
Solved!
Go to Solution.

With scripting, there is a property node for the case structure and you can query the names of the cases. You will need LabVIEW 8.6 or greater for scripting. Get started here. Note that scripting is unsupported, except through the scripting message board.
This account is no longer active. Contact ShadesOfGray for current posts and information.

Before the selector value reach a Case structure I need to stop it until a push button is pressed. How to do?

Before the selector value reach a Case structure I need to stop it until a push button is pressed. How to do?

altenbach wrote:
UliB wrote:
simply wire your selector value through a while loop. Stop the loop with your button. After the loop stops, the value will go on to the case structure.
Hmmmm.....
Hello altenbach,
roflol .
Thank you for the link to 'A Field Guide To LabVIEW Objects - Selfish Loop'. I'll keep that in mind, when answering other questions with while loops.
Uli

How to implement Case Structure for multiple inputs to Pic Ring?

So I have a reasonably simple program which I am almost completeed with. Basically the data of an array is read and then is indexed and a new array is created from the indexed data. And then I use Match Pattern to see if elements in the new array match certain words. And if they do then a number value is allocated to a Pic Ring at the end. And depending on the final number value the Pic Ring changes from one pic to another.
However, I have the problem that I will be using multiple Match Pattern functions to compare elements in the final array, but I can't attach multiple Match Patterns and their subsequent logic statements to a single Pic Ring, only one. I've been trying to work this out by implementing a Case Structure or Event Structure. But the Event Structure isn't working and with the Case Structure, it is very messy with multiple True/False Case Structures inside of each other. Anyway, hopefully this all makes some sense. I'm attaching the VI program to this post. Thanks.
Attachments:
ArrayTest2.vi ‏495 KB
ArrayTest2.vi ‏495 KB

Obviously, you can only display one picture. So then the question becomes which picture to show. Therefore, you will have to create some sort of preference of one pattern over another.
I would use a FOR loop so that you can loop through your available patters and their possible results. Use the Conditional Terminal on the FOR loop so that you can stop the loop on the first match. Then you just wire up the selected value for the ring outside of the loop.
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Case Structure Nested in a For Loop

I have two pumps. I want one pump to be running and the other pump to be off. Then as soon as the first pump stops I want the other pump to start. I'd like this process to repeat as many times as I want. The code I have now uses a case structure inside a for loop. When the iteration is odd it is false and even is true this determines what case is carried out. Right now I have a code that can turn on one pump, stop it, and immediately start the second. However, after the second pump stops the first one does not start again. I've changed the number of iterations and I can't seem to get the process to continue. The program keeps running but the pumps stop doing anything. Attached is a file of my code as well as two image files (one showing true case and other showing false) of the same code.
Attachments:
Test Code 1.vi ‏31 KB
Case if True.png ‏37 KB
Case if False.png ‏35 KB

Your code has an inner while loop that checks for the status of the pump. Since you set up a target volume before the while loops start, I assume that it is what the status checks to determine when to stop the while loop.
When the the second iteration ends, has the volume for the first pump changed at all? If it is still the same, then the status is still at the target which means it will immediately stop after starting. You may also want to put some small wait statements inside the inner while loops so that the status isn't checked as fast as the CPU will allow it to run eating up CPU cycles.

Case structure for comparing values

Hi,
i just wanted to know if there is a special way to use comparison in case structures.
I only kow how to create cases for things like if x=0 then ... if x=1 then ...
Now I want to make it if x<0 then ... if x=0 then ... if x>0 then ...
The only solution I found so far is creating a case structure inside a case structure.
Is there a way to keep it all in just one case structure?
Thanks and have a nice weekend,
Bernie

Case Structures are pretty flexible in how you can specify what triggers a particular case. You can specify ranges or various values per case.
In your situation, if you specify three cases with the following values, you'll get what you want.
'..-1' = x<0
'0' = 0
'1..' = x>0
The two periods before or after a number indicate that the case should run if the value is anything less than or greater than the specified number, depending on which side of the number you place it. You can also use this to specify a range of number. '1..10' would trigger the case for any value 1 through 10. Using a comma between numbers lets you specify different non-sequencial numbers. '1,5,10' would run the case only those specified numbers.
The same basic rules a
lso work with text based Case Structures.
Attached image shows the three cases you need.
Ed
Ed Dickens - Certified LabVIEW Architect - DISTek Integration, Inc. - NI Certified Alliance Partner
Using the Abort button to stop your VI is like using a tree to stop your car. It works, but there may be consequences.
Attachments:
Case_Range_Values.gif ‏21 KB

Wiring inputs n outputs for case structure

Hi everyone...
I have a simple basic question...How to wired the correct tunnel for output in case structure.Because when I try to wire the build array to the case structure, It shown as white terminal....How how to make solid color terminal for output tunnel...Actually I forgot how to wire it correctly..so...I hope u guys can remind me again...thank u very much...
Attachments:
Cepat21.vi ‏43 KB

Hi Altenbach...
Thank u very much for ur
help.I'm always make a careless mistake.thanks to u guys.Now,I'm be able to display my
data into table something like attachment below.Actually I'm using IIOA
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V = 238.25 I = 23.82 P = 5676.12
V = 237.79 I = 23.78 P = 5654.28
V = 237.35 I = 23.74 P = 5633.54
V = 236.94 I = 23.69 P = 5614.09
V = 236.56 I = 23.66 P = 5596.12
V = 236.22 I = 23.62 P = 5579.80
V = 235.91 I = 23.59 P = 5565.29
V = 235.64 I = 23.56 P = 5552.72
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V = 235.11 I = 23.51 P = 5527.78
V = 235.03 I = 23.50 P = 5523.98
V = 235.00 I = 23.50 P = 5522.52
V = 235.02 I = 23.50 P = 5523.40
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V = 235.21 I = 23.52 P = 5532.16
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V = 235.84 I = 23.58 P = 5561.99
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merge it with signal.So, it looks like complicated like u imagine.
Now,I have one other question.refer to my vi, I have used elapsed time
so that it will run from the start time until target time.But its only
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time for day.I mean this prog will start on Monday for example n stop
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Attachments:
build table1.PNG ‏36 KB
Cepat2122.vi ‏165 KB

Pass the value of the current case in a case structure to a global variable for use in VIs.

I have built a large queued state machine (>100 cases). In each state, I run a VI that I have created. These VIs are usually not very different from one another. In many cases, I could simply use the same VI over and over again. There is only one problem with that. None of these VIs know which case to send the program to next. I have to change the value of the "NEXT_CASE" constants in the VI and save it under a new name to be inserted into each new case. Now my program consists of hundreds of VIs whose only difference is the value of their "NEXT_CASE" constants. This causes all kind of headaches when I have to insert new cases into the state machine, and it is just too much for me to deal with.
I need to be able to use a global variable to keep track of the current case within my VIs. I could change it from a string to a number and add or subtract from it to determine which case the program should go to next. Since I'm usually only skipping from one case to the next (or the previous) I could use the exact same VI in most cases. Can anyone tell me how to create a global variable that contains the value of the case in my case structure that I could use within my VIs to keep track of the current case? Let me know if you have any questions.

Instead of defining the next state inside the subvi, why not do it in the main vi inside each state case? An output from the subvi could be used with a case structure to determine the next state. Sort of like, if the subvi returns 0 then next state is State3, else if the subvi returns 1 then next state is State4.
Message Edited by tbob on 08-19-2005 03:15 PM
- tbob
Inventor of the WORM Global
Attachments:
NextState.PNG ‏5 KB

How to implement index array inside case structure for searching a 3D array?

Well I have a 3D array and I want to index certain elements from that array. And I have thought of one way of doing this is to have multiple index array functions on the block diagram to search the array simultaneously, but that would be messy. Or I could setup some kind of case structure and place each index array function into individual cases. I've tried the latter, but when I connect the 3D array to the case structure at the"?" it doesn't give me permission because it says I'm hooking up two different types of data. Case Structure is for T or F and 3D array is not a boolean.
So how can I setup the Case Structure to work for a 3D array?

A case structure's selection tunnel cannot accept an array. What exactly are your search criteria? It sounds like a few FOR loops will be needed.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines

I have a case structure writing a digital out and I need it to express this case for 1 min......how?

basically I just need to know how to make my case structure express a certain case for a specified amount of time. thanks...

Two ways
Use a Functions palette>>Time and dialog>>'wait' function and set a 1 minute delay( 60000 m sec) delay
If using a state machine, do a state transition only after the specified time has elapsed, as shown in attached vi
Hope this helps
Regards,
Dev
Attachments:
n sec wait.vi ‏29 KB

Shortcuts for case structure manipulation?

Hello all. I'm curious if there are keyboard shortcuts for duplicating cases or deleting cases in a case structure. I'm also interested if any of you have any tips or secrets to working with large case structures - LabVIEW mods that enable a storyboard-style case structure reorganizer, for example.
Thanks!

JLS wrote:
Another useful feature of case structures is that if you use an enumerated type for the selector, you have the option to "Add Case for Every Value.
Yes that is handy for enums with a handful of values.
The other feature I like about enumerated cases is the ability to NOT have a default case.
When this is the situation, LV will remind me that I have not coded up all of the cases in the event I missed one.
This is very handy in applications where you have a bunch ( 100 or more) of enum values.
If at a later date I decide that I need to add enum value #101 then I edit the typedef and then LV reminds of all the places I have to go and fix.
Just a different approach for a different challenge.
Ben
That reminds of a related trick I have not heard anyone mention lately.
Bonus Q:
Given a list of all of the enum states (array of strings), what is the easiest way to create an enum with all of those values?
Correct answers are worth 5-stars!
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction

Property node for case structure

Is there any way to programatically pull out the list of cases (strings) from a case structure at run time?

Thank you tbob and tst. I do use the enum "trick" in other places (I once saw it used in an example somewhere) and I am nervous about the Selector Strings property available through scripting after reading about it on the LAVA forums site (I am a novice LabView user and I mostly didn't know what they were talking about).
I have a VI that processes "tags" embedded in various text fields that many of my collegues use. As an example we have a custom front end to the LabView simple error handler that processes our custom error codes and handles timed popups, writing to the device error log, etc. The default behavior can be modified by inserting tags (<popup 60> for a dialog box with a 60 second timeout or <no device log> to supress writing an entry to our device error log) into the "source" string of a standard error cluster -- just like the <append> tag used by the Simple Error Handler.
In most instances there are only a few tags so I just use a case structure in the "tag processing VI" to select the desired action indicated by each tag. When people are parsing their strings for tags, they like to have a qick and easy way to test if a string is a vaild tag. I provide a separate "validator VI" to do this. I frequently add and remove tags from the case structure as things evolve, but I often forget to update the list of valid tags used by the validator VI or some one runs into an older version on another machine. I wanted to have the vaildator VI access the case structure on the tag processing VI to get the current list of vaild tags.

Combine 4 stops for 4 case structure

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