Quantcast
Channel: LabVIEW topics
Viewing all 66786 articles
Browse latest View live
↧

Shared Variable Engine - as an OPC Server - U64 datatype issue

November 3, 2017, 4:53 pm
$
0
0

I am testing out utilizing the SVE as an OPC Server for some third party visualization software.  Using the SVE for the tags will be very nice, but I am having a bit of an issue with U64 Shared Variables showing up under the National Instruments.Variable Engine.1 Sever when I browse for Tags under the server and inside my Variable Library.

 

When I reconfigure the Tags as U32 type - they all show up and I can connect with no problem and see the values changing as my simulator code updates the U32 tags via LabVIEW 2016 and using the Shared Variable programmatic API to update the SV/Tags.

 

QWord (U64) appears to be supported by the NI Quick Client - yet when I browse for the tags they don't show.  I don't really NEED to use U64 for these counters as the process could never physically produce that many counts in a day of processing, but I find this really strange.

 

Note: I get the same results when I use the DataSocket Select URL.vi and search for OPC items (Option 4) on the Options input.  U64 Shared Variables do not show, U32 variables show up. 

↧
Search

Report generation toolkit not working with LV runtime engine after upgrading to MS Office 2016

November 3, 2017, 7:16 pm
$
0
0

Hello all,

 

I have a project inside which some functions of report generation toolkit are called to access EXCEL spreahsheet. For it to run on a target computer I build an exe with application builder and have LV runtime engine installed on the target computer. On the development computer there is LV 2015 installed. On the target computer there is LV runtime engine 2015 installed. Everything was OK even after we upgraded MS Office from version 2013 to 2016 on the target computer.

But that is the end of the good story.

In order to add new features to the project I have to recompile it and build the exe again. The new exe after that does not work on the target computer anymore. Running a remote debugging helps me to narrow down the error to the following subVI of report generation toolkit,

New report.vi

The same exe works well on the development computer though.

Both computers run on MS Windows 7 64 bit but the LV development is with 32 bit version.

I tried the Registration table trick that on mentioned on this link

https://forums.ni.com/t5/LabVIEW/LabVIEW-2014-report-generation-toolkit-excel-2016-and-office-365/m-p/3260088#M950902

But that does not help after I deleted the whole folder of "19.0" that corresponds to the installation of EXCEL 2016.

 

I hope someone in this forum could help me to figure out the root cause of this and find the solution.

 

Thanks,

Tao

↧
↧

Input error causes strange enqueue/dequeue behavior

November 3, 2017, 10:23 pm
$
0
0

I've attached a minimum working example that demonstrates that when the "error in" input is true for the enqueue function, an empty string element is enqueued.

 

Can anyone explain this behavior? I couldn't find anything in the documentation that explains that the error state has any effect on the enqueue function behavior.

↧

LabVIEW host failed to download abcd.vi to RT Target

November 4, 2017, 4:05 am
$
0
0

Hi,

     I am having a code which takes an Enum Typedef Input and selects the appropriate Module Class Object (and Child). There is a VI Reference Selector.vi (Dynamic Dispatch VI) for all the Module and Child Class Objects. Then there is methods called Launch.vi which will dynamically call the VI using Start Asynchronous Call Method.

 

The code works fine in Windows environment. There are no broken VI's for any of the Class VIs.

I tried to deploy the same in my PXIe 8840 RT controller. I get deployment error for the Launch.vi where I launch the modules. I tired mass compiling, creating a duplicate VI.

I tried clearing the compile cache etc. I'm currently stuck now with the current implementation.

I would like to know how to fix the issue.

 

If anyone has worked on Dynamic calling of VIs and LVOOPs in LabVIEW RT please suggest.

↧

2D HISTOGRAM OF A 2D ARRAY

November 4, 2017, 4:17 am
$
0
0

HELLO TO ALL!!

 

I ve got a 2 d array of random number and i want to cerate the 2d histogram of it by using the  

Advanced Plotting Toolkit , 

2d hist example,

however in this example i see only 2 entrances  of 1d arrays of X , Y bins ... i cannot understand how i could connect my 2d array ..

 

any ideas  please??

1.JPG2.JPG3.JPG

 

 

 

 

↧
↧

CLD-R Exam 1, Question 22

November 5, 2017, 12:46 am
$
0
0

I am sitting the LabVIEW CLD-R exam in a few days & attempting some of the sample questions.

Question 22 has me stumped, I just don't get it.

I tried it in LV 2015, and can't seem to get the correct answer.

 

Can anyone explain to me whats happening here, (I generally don't use recursion, which is why I don't get it I suppose).

I will attach my attempt (that does not work..)

 

Thanks in advance for anyone's help

↧

Language support

November 5, 2017, 1:08 am
$
0
0

I have created a application in English.

1) I want my labels to be displayed in Chinese 

2) My application generate some report , i want that complete report to be translated in Chinese language.

↧

Still confused about medain filter.vi

November 5, 2017, 1:55 am
$
0
0

Hi all!

 

I'm trying to use median fitler. But I'm not quite sure about how to configure it.

1. Does left rank and left rank mean the number of elements counting from the value at the center? For example, if i have five data points, and if I set the left rank=2 and right rank=2, does median filter.vi give me the 3rd data point(by 3rd data point I mean counting from the smallest value)?

2. The description of median filter.vi says the output, filtered array is the same as the input array. But how does this work? Isn't the point of having a median filter is to drop the undesired data points? Like if I have 5 data points, and I use the medain filter.vi, how can I just get the 3rd biggest value?

3. If I have 100 data points, how will medain filter.vi filter them? From the description, I think it will make the data into group of, let's say, 5, and get the 3rd biggest value from each of these groups, and return these 3rd biggest value, maybe??? Cause if this is the case then the output will only have 20 data points and it's not the same size as the input array

 

↧
Search

Arduino Mega Encoder VISA synchronization in Real Time

November 5, 2017, 4:56 am
$
0
0

Hello
I'm using arduino mega and i need to create some control system in Labview in real time.
I'm using a control and simulation loop and VISA to get a signal from arduino. My code in arduino:


volatile unsigned int counter = 0;  

void setup() {
  Serial.begin (9600);
 
  pinMode(2, INPUT);           
  pinMode(3, INPUT);           
  
  digitalWrite(2, HIGH);      
  digitalWrite(3, HIGH);       
 
 
  
  attachInterrupt(0, ai0, RISING);

  attachInterrupt(1, ai1, RISING);
}

void loop() {
  // Send the value of counter
  Serial.println (counter);
  delay(10);
}

void ai0() {
  // ai0 is activated if DigitalPin nr 2 is going from LOW to HIGH
  // Check pin 3 to determine the direction
  if(digitalRead(3)==LOW) {
    counter++;
  }else{
    counter--;
  }
}

void ai1() {
  // ai0 is activated if DigitalPin nr 3 is going from LOW to HIGH
  // Check with pin 2 to determine the direction
  if(digitalRead(2)==LOW) {
    counter--;
  }else{
    counter++;
  }
}


Then i made a sketch. But i can't understand how to get visa read signal and control simulation synchronously. I'm trying to vary delay() in arduino code but the precision is not good. Maybe someone have ideas about this?

↧
↧

Read from NI Distributed System Manager

November 5, 2017, 7:50 am
$
0
0

Hello all

 I need help in how to read data from  NI Distributed System Manager to LABVIEW (real time)

Think you

 

 

 

↧

Video Playback with Simple State Machine

November 5, 2017, 8:17 am
$
0
0

I'm not sure wether it's possible to realize a Video Playback with the Simple State Machine Template. For example I have are two Buttons: Play and Pause. Furthermore the states Initialize, Wait for Event, User State Play and User State Pause.

When I press play, it plays one frame and goes back into Wait for Event. I want it to stay in User State Play as long as no other button is being pressed. But there can only be user input in the state Wait for Event. Is it possible to realize a Video Playback with the Simple State Machine?

 

Version: Labview 2017

There are some pictures of the Block diagram attached.

↧

PXI_Clk10 for Timed Loop DAQmx Timing Source

November 5, 2017, 10:38 am
$
0
0

I'm trying to set a timed loop that uses a DAQmx counter channel as the timing source. I'm able to set up the timed loop and everything works as expected but the problem is after the timed loop starts I'm attempting to start a analog input task and it errors out for reference clock in use. I'm aware of why this problem is occurring (which is explained here: Why Do I Get a Resource Error -89137 When Using a Reference Clock with NI-DAQmx Devices?) but how can I specify which reference clock the timing source uses? The timing source property node doesn't seem to have anything to specify that. Any ideas? 

Timed_Loop_Problem.png

↧

LabVIEW crashes every time a certain LVOOP project tries to close

November 5, 2017, 12:49 pm
$
0
0

I have a project in LV2015 that uses LVOOP. Every time I try to close the project, LabVIEW crashes hard. Are there any known issues around symptoms like this? Perhaps any project xml clean-up utilities that might help?

Thanks,

    DaveT

↧
↧

LabVIEW integrated with Vectrino (ADV)

November 6, 2017, 1:01 am
$
0
0

Dear All,

I want  to get the water velocity data from the Vectrino measuring in the open channel flow of flume. The data  will be generated by using LabVIEW  after connecting the Vectrino to PC.

I am in obstacle of integrating between LabVIEW  and Vectrino. How can we integrate this vectrino (ADV ) with LabView software ? and I  wondered that if this integration is possible ., so  it would be integrated by using cable directly or via coding?

Anyone  helps me , I will be so appropriated .

The Best Regards,

↧

Create multiple plots in XY-graph in word using report generation toolkit

November 6, 2017, 2:01 am
$
0
0

Hello,

How to create the XY graph in word using report generation toolkit?

Please find the below snippet and csv files.

xy graph.png

Kindly help me to continue the documentation part.

 

Regards,

S Nagaraju.

↧
Search

How get the execution control back without waiting for child to complete its execution?

November 6, 2017, 2:33 am
$
0
0

Hi,

 

In my application I want to continue the execution in the caller VI without waiting for class method to complete its execution. Please refer the attached screenshot of a simple example, the caller vi calls UI.vi method which will continue execution until a user presses stop button, this halts the For loop in the first iteration. How can I avoid this and make For loop to continue execution ?

 

thank you

Adarsh

↧

Automation Refnum -invoke node- WinSpec32 Problems

November 6, 2017, 4:00 am
$
0
0

Hello, I am running the winSpec.exe as administrator , but when i try to call the .exe through the automation refnum , the vi is not executing. I have attached the snips of the errors.

↧
↧

a basic questions about enum and Waveform Chart

November 6, 2017, 5:20 am
$
0
0

Hi everyone, 
I almoust finished my measurment program.
But I have some problems with basic things.

1. When I start the program I want that every enum control in my GUI is set to "/" and not "wait" or "8" as its now. I tried to reorder my typedef but it didnt help. How should I do it?

2. On my Waveform Chart on the x-Axis is the absolute time, but i would like to have a relative time that starts from 00:00 when I start the program, and ends when the program comes to the end. I tried to do it, but somehow it didnt work.. I couldnt correct the starting point to 00:00.. do you have any ideas how to do it?

Thanks in Advance,
Vlado!

↧

Write on DMA FIFO sbRIO 9606

November 6, 2017, 5:58 am
$
0
0

I have 2 FIFOs, both set up like this

large.png

 

One target to host and the another one host to target. My work consist in encrypt files using the target, both that isnt the problem. When I write(in host) and read the proccesed information of 10,000 bytes works fine, but when i try to encrypt files of ~25 Mb i got an error. I have observed that modifing my time loop period (i have 10 uSec) (in target vi), i can process larger files (~40k elemnts). So i have some doubts.

 

1) Why if my file is bigger than 2047 elemnts, works fine? and Why if my file have ~25mb doesnt work? 

2) How the loop period intervenes on my cycle?

↧

Create a new menu from custom action

November 6, 2017, 6:56 am
$
0
0

I want to create a textbox with autocomplete, showing up as a menu with matches, where the user can select which word to select.

Like the picture below but the matching words showing up instead of the current right click alternatives I used to show what I wanted to achieve.

It is possible to create a custom menu that I can show when and where I want and how would I do that?

↧
Viewing all 66786 articles
Browse latest View live
Search
<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>