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Dynamically Dispatching for User Input; best practices?

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Hi all,

 

Using LabVIEW 2013 (32 bit). Taking my first foray into LVOOP and I'm currently designing our user input. This User Input VI is dynamically dispatched. The goal is to allow to user to "mix and match" different pieces of the application as much as possible. The application is for a controller of a biological system. In particular, we have the notion of a "Controller", a "Model", and a "Patient". Patients all carry the same characteristics, but controllers and models only share an external interface. Some controllers may control to a set point, some to a range, some to a set of ranges depending on the time and current state of the Patient. As such, I'd like to have some sort of dynamic dispatching going on during the user input phase. The way I thought to do this was via subpanels, with a tab control to allow the user to jump between different parts of the setup process.

 

Here's a mockup of the User Input front panel:

 

http://i.imgur.com/sMZ7xFD.png

 

So if you have a certain controller, that controllers UI panel would show up in a subpanel, via some sort of dynamic dispatch. This would allow you to seamlessly switch between controllers and still have a consistent User Experience, eg controller 1 may have you choose a range to control to (two digital numerics), whereas controller 2 may have a set point to control to (just one numeric), like so:

 

http://i.imgur.com/6QpKXco.png

 

http://i.imgur.com/u2mla8N.png

 

You can assume that we have access to the instances of the Controller class, the Patient class, and the Model class at this stage for dynamic dispatching.

 

When I tried to implement this, I ran into problems:

 

http://i.imgur.com/2ZZqdka.png

 

The error that occured is: "Call by Reference: refers to a dynamic member VI; The connector pane of the strictly typed VI reference input includes a dynamically dispatched terminal, which means it is part of a method of a LabVIEW class. Dynamic member VIs are not supported by the Call by Reference node in this version of LabVIEW."

 

I understand the problem, maybe this is too much overhead for LabVIEW to handle cleanly, but is there a way for me to maintain the "niceness" of dynamic dispatch in this particular instance?

 


DAQmx Base maximum AO write rate

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Hi,

 

we are running LabVIEW 2015 on OpenSUSE, which means that we have acces only to DAQmx Base. We want to generate a waveform and write it using the DAQ card NI-6289.

 

However, it seems that the DAQmx Base is limited to write rates of about 8000 samples/s. When trying to write faster, an error occurs stating that DAQms Base does not use buffer and so it can not write faster. Is there a workaround around this to generate samples much faster?

 

If you want to replicate this error, use any of the DAQmx Base AO examples and set the number of samples few hundred higher than 8000 per second.

 

Best Regards

 

Petr

File Dialog Wrapper.dll (64-bit)

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I'm currently using LabVIEW 2015 (64-bit) and am encountering a Call Library Function error because my dll is a 32-bit version. Does anyone have or knnow how to create a "File Dialog Wrapper.dll" 64-bit version that I could try? I'm completely unaware of how to do anything to create or modify a dll. Any help will be appreciated.

Thanks, JoshFile Dialog Wrapper dll.PNG

How to get India date and time from any website

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Hello,

I have to get India time and date in my labview program. This is to compare this standard time with the real time clock of my device and show difference. How do I fetch the current time and date. Should I use a webservice ? How to do this ?

Thanks ..

Activate Switch

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Hi,

 

         I have a signal being read, I should activate another process if there is no difference in the value from the  last 100 measurements from the signal (say around 1% deviation). Can anyone help.

 

Best Regards

Hari krishna

Read from tab delimitted text file and write to csv

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Is there a way to read a tab delimitted text file and then write that same data to a csv?

I need to do this, but I don't know how to pass from one type of format to the other.

Can someone please help me?

Thanks.

DataSocket and datadasocket Firewalls

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Hi,

I am planning to build and application that distributes and collects data fro multiple clients via internet conection. I am quite fond of the datasockest server approach due to its simplicity.

I do not have much experience with datasocket and have two major concerns:

 

1. Though I have full control on the server side PC running the datasocket server and the server-side VI. (i.e. I can Disable firewall, define static IP , and most importantly -port forwarding). I do not have any control on the client PC that is running on the client application.

I have read article http://www.ni.com/white-paper/12402/en/. But still do not understand what has to be done on client side. I know for a fact that when the client will install Labview runtime and when he will run my application (exe program) he will be prompted by the windows OS to "allow access to labview program" (or somthing like that...)

Is this the only step my clients should do to configure there firewall. I am afraid I can not ask them to do any action beyond approval my application access during installation.  Should I be concerned from other issue, related to security form the client side? (clients are pribably regular domestic clients, with avarege routers).

2. Please have look at the diagrams. is this an acceptable approach fro multiple client connection? (i do not plan more than 10 clients, so scalability is not a big issue.) the diagram ilustrates application runing on each clients PC. And VI running on server PC colecting data from 4 clients.

 

Thanks!Client.JPG

 

Client.JPG

sbRio-9637 Scan Engine

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Hello there,

 

I´m using a sbRio-9637 to measure analog voltages. I was wondering why there is no option to put the chassis in Scan Interface programming mode? How am I supposed to use the I/O without the Labview FPGA module? Will there be an update or is a Bitstream for the FPGA avaiable?

 

Thank you in advance.

Best regards,

Gert


Unregister for Events leaves Callback-VIs loaded

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I'm usinge the C# Class NotifyIcon to get my application into the system tray bar of windows. Since I use this function, most classes get locked after running the application.

 

I found, that all loaded callback vis remain locked after running the application, therefore some typedefs are locked, therefore some classes are locked, therefore allmost all classes are locked.

I found the same problem with this example: https://decibel.ni.com/content/docs/DOC-9161

 

In LV 2010 SPI1 it works fine, but in LV 2014 SPI1 the VI CallbackVI.vi remains locked after running and stoping HandlingEventsInLabVIEW.vi. Also if you close HandlingEventsInLabVIEW.vi first and then CallbackVI.vi (both without any project) the 'GettingStarted' Window wil not appear and you need to kill Labview.

 

Since the problem appears in LV 2014, not in 2010 (I don't have other versions) I assume a problem with LV 2014 itself.

Any suggestions?

fpga servo motor+ultrasonic

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hello everyone, i'm working on a project for robot obstacle avoidance, i'm using fpga on myrio to control the position of the servo motor which sweeps a certain area defined by theta min and theta max with a step theta, an ultrasonic sensor is mounted on the servo and should take a distance reading at each step angle. the current position angle and its corresponding distance reading should be synchronised and corresponding to each other. then i will take this data to a host vi which is not a problem.

i was able to operate and control the servo motor as i want and i was able to get the readings from the ultrasonic sensor (i have hc sr04 and ping) on the fpga separately, however, when i try to make them both work at the same time, i have no luck doing so.... i have tried many things and searched all over.... can anyone please guide me what to do?.... i have attached the last fpga code that i came up with, i dont know what is wrong with it.... thanks)))

how to switching arduino thermistor with visa temperature read ?

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hello, i am working on my final project to controling temperature,

 

at first i use a thermistor, and now i want to change it to a thermocouple. i was made the Vi program for it, but i still dont know how to connecting it.

 

i attached the file down there, and i wanna ask is it posible to swtching number 1 with number 2 as attached in "subs.png" down there

 

i hope someone can help me

thanks.

 

 

running multiple user interface events

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I created a LabView VI using the "User Interface Event Handler" template.

 

While one command (event) is executing, I would like to be able to process and execute additional user events.

 

For example, button 1 executes a power interrupt by sending a power off command to the remote device, waits 10 seconds, then sends a power on command.

 

While I am waiting 10 seconds to execute the ''power on' command, I'd like to be able to run 'button 2' and so on.

 

Thanks for your help...

Oscilloscope Not Mapping to Waveform

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I'm trying to get the oscilloscope reading from channel 3 and put it into the waveform V_RECT, but it isn't working for whatever reason. Can anyone help?

Capture4.PNG

Configure Oscilloscope to read channel 3 with specific boundaries.

Capture3.PNG

Reading the source of the waveform graph.

Capture2.PNG

The while loop that transfers the oscilloscope reading to the waveform.

labVIEW 2011 executable won't run on windows 10 computer

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A colleague of mine created an executable with LabVIEW 2011 that uploads measurements to a database. It runs on a laptop with Windows 7 but it won't run on a Windows 10 laptop. I can edit the original VIs in LabVIEW 2015, but creating a new executable in LabVIEW 2015 does not solve the problem. It will run in Windows 7 Compatability Mode on the Windows 10 laptop, but I would like to not have to select that option every time I install the executable on a new laptop. Any suggestions? 

LabVIEW Crashes in External Testing App

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Hi,

 

I am accessing LabVIEW from a third party test sequencing application (which uses TestStand for sequencing).  Occasionally while running our test, LabVIEW crashes and provides the attached lvlog report.   Help interpreting this report would be appreciated.  Also, if there is more useful information I could provide, let me know about that too.


Thanks,

Billy


PCAP Offline Data Read.

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Dear all,

 

 

I want read PCAP file which is captured from WIRESHARK. can any one help me how to capture oflline PCAP File using labview..?if   any code is der  capture please get back to me..

 

Thanks & Regards,

Muniraju M

CLAD

Image Reconstruction Issue

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Hello,

 

As a test set up I have created a BMP image, which I then decompose and then want to reconstruct.

 

Decomposition:

Into 1D array, 30pixels at a time, row by row (180 pixel wide image = 6 iterations) as can be seen in the first while loop of the image.

Hence first 30 elements of the 1D array will be pixels 0,0 - 0,29, next thirty will be 1,0-1,29 etc.

 

I then attempt to reconstruct the image, and it looks like it works except for the last row of 30 pixels where the image does WEIRD stuff, it looks skewed...

 

I have attached both my labview code, and picture of the reconstructed image.

 

The decomposition is a little confusing and if necessary I can provide a picture description.

 

Thank you.

Modify Front Panel Layout and Waveforms

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Hello,

 

I have some questions about LV configuration:

1. Is it possible to modify appearance of waveforms? Colour, 3D effect, font...

2. How can i join 8 graphs into a single block. I explain, i have 8 sepparate graphs but i want to graph them into a same block but in different lines.

3. Is it possible to delete the background grid?

 

Regards

programmatically populating or showing/ hiding options in enum or ring control

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Hey guys,

So my problem is that I have a list of known selections that I would like in something like an enum or ring control, the user will have to click on one option and something will happen unique to each selection. the program will have many pages where the enum/ring will be present and on each page the options available will be a relatively unique grouping of the known values.

 

basically options 1 - 6 are already known to exist.

on page 1 the drop down shows options 1, 2, 3

on page 2 the drop down shows options 2, 4, 5,  6

....

 

every page will have some combination of the options.

 

also this isnt random, im pulling the page and the list of items for the list from a database.

 

Im trying to think of a good way to do this, my guess is my options are rings or enums but if theres something else I could use to generate lists like this at run time I have no problem looking into it. I was looking into using the strings property node to take the strings of options from the database and populating the ring control but how do I keep the value of the ring always associated with the proper string? I could use the value and string property and just pre associate the database strings with the proper numeric value.

 

I'm just wondering if there's a better way to go about this.

 

Thanks for any help

Read daqmx unit property from a task

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Looking for a way to read the units of channels in a task. Right now the only way that I know of doing that is to actually read data then query the data. In this instance I do not want to do it that way I'm looking to read the units from the task. I do have custom scales applied so I know that complicates things.

 

Thanks

 

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