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Writing with VISA while reading.

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Hi, I am working with some ADAM-4000 series module and I am trying to write some commands while I am reading the values on one of the modules. I think the solution can be simple, but I don't have very much experience in LV and maybe I am missing it.

I am using VISA read and write for this operation and everything works well. The value that I am reading constantly will be a temperature sensor for the final purposes of this project. This temperature will be displayed on a graph and maybe saved to a file also. My problem is that if I want to send another command to control something else (on the same COM port but different module) I can't read the temperature while the command is sent and executed. This is creating a portion of the graph(possible 0's in the file) that I don't want. Is there a way, to save the last value before the 0 and faking the read in the graph while the extra command is sent? Or maybe is something that can use delays or time loops that may work?

 

In the attachment, the main command is #051 that will be sent continues and from the dial, I am creating a string with the next command. When the "OK" button is pressed, the case structure will switch from the initial command to the one created by the dial.  

 

I am sure that is something small that can be changed or a different approach regarding how the extra commands may be sent while still reading from the module.

 

Thank you in advance and feel free to ask anything that is not clear from my description.


Fgen multitone VS RFSG multitone

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Dears,

 

There are two examples (FGen & RFSG) deal with generating multitone in the NI examples. I usually use the RFSG example but I don't know what are the differences between them? any idea? Thanks in advance

 

 

XY graph Cursor list - get/set column headers

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Hello,

 

For translation purposes, I need to read/write headers on cursor lists displayed on graphs.

I can not find valid property, maybe someone has an idea where to read it??

 

translation.png

 

Worst case scenario I can hide it but that is no real solution...

 

Stop DAQmx after movement & variable delay

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Hi all,

 

I am very new to LV and am having a tough time with what seems like it should be a simple problem.

 

I am designing an experiment where I want to detect when people perform a thumb movement (over a threshold movement size criterion), then play a sound, then wait somewhere between 1-2 seconds and stop reading/ writing the output to tdms file.

 

 

It was working when I initialised the program (because 'change time' was initialised to 0)

Therefore, when my threshold was reached, this set 'change time' to the current loop time from 0 --> comparison time became less than change time (by the amount of my variable interval) --> it sent a stop signal

 

But I want to run multiple trials and I can't work out how to get the 'change time' to start at 0 again for each while loop...

 

VI is attached (sorry about all the indicators, was using them to try help work out the problem)

 

Any help would be greatly appreciated - I am going to have a problem with my boss if I can't get something working soon!!

 

Thank you,

 

Harriet

Not getting data through RS-232 cable in LABVIEW through VISA serial

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Hello,

Actually, we are working on Data Acquisition system using 89C51 micro-controller. We have been interfacing analog sensor to 89C51 through ADC0808 and after getting the digital data on a port, it is programmed so that it converts the digital data of (0 - 5 V) in 0-255 number format(as the ADC is 8-bit wide) and then transmitting the data from micro-controller through serial communication via RS-232 port(MALE).

 

But we do not have direct Rs-232 port on our laptop, so we are using USB to serial DB9 connector and female to female DB9 connector(as our port is MALE one) for their respective connections(please find the attached photo).

 

In labview our aim is to indicate data coming from RS232 port(which is in the form of number) we are using VISA serial function palette and reading the data from VISA read.

We have NI VISA 17.0 installed, is there any additional requirement ??

And we are facing the problem of not getting the data in LABVIEW.

 

Actually we don't know where we are wrong, whether we should use VISA serial or VISA usb ??

So kindly help as soon as possible.

 

We are attaching the required files(images).

Thank you !!

Best Method to analyze a VI

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Hi all,

i'm trying to study a VI with more than 20 SubVIs and DLLs so it's confusing sometimes .

so any suggestions or steps to make it more easier 

Thanks 

How to build safety login system?

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Hello,

 

I'm building a simple user login system. like following

01. Build a database(SQLite)

02. Insert the login information( Username and password)

03. Login Interface, the vi will search the match User.

 

But i think it is too risky, because anyone can access the database via kind of tools.

Can you share the experience to us about the safety login system?

Inspect Image for Defects

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Hello 

I have images for car parts and need to check each part for fractions Just like the images attached 

I tried to use the golden template but it will not work if the image moved even a bit.

then i tried the  map defect but may some part be thinner or thicker 

so 

any ideas please Smiley Happy

 


60秒毎にプログラムを実行するにはどうしたらよろしいでしょうか。

Programatically get the label of a connector

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Hi,

 

I want to compare the output of a VI to a value read from a file. The file is written in with multiple key-value pairs. I want to programmatically make sure that the key matches the Label of the VI so if my VI has "Channel" and "Status" as outputs, I want to compare the output of "Status" from the VI with the value paired with the "Status" key. Is there a way for me to get the label of a VI's connector as a string so I can do a string compare to make sure the VI's connector label is the same as the key? 

 

Thanks 

 

EDIT: I'm using Labiew 2010.

How to convert a vi from windows 7 to windows XP ??

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HI:

 Thank you for help.

(1) I have development PC run windows 7 with labview 2013.

(2) I need make a change for one vi to transfer to a PC run Windows XP with labview 10.

(3) I made a change in development PC and save it as labview 10 version.

but when I copy it to a PC with windows XP, it has below error.

====

Possible reason(s):

 

LabVIEW:  VI is not loadable.

 

In a built application, this error might occur because the VI being loaded was last compiled for a different OS, in which case you must save the VI on the current platform. This error also might occur if the VI is a polymorphic VI, which cannot be loaded in the LabVIEW Run-Time Engine. You must load an instance of the polymorphic VI instead of the polymorphic VI itself.

===

 

Thanks

 

 

 

How to convert a vi from windows 7 to windows XP ??

labview 2016 + windows 10 slow down

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Hello:

 

I have designed an application I use in my classes: two projects, each of them with just one .vi, that share information via shared variables using the DSC module; the values of one of the variables are read from an Arduino using the Arduino blocks provided by LabVIEW and Lifa BASE.

 

On previous years the application worked on Windows 7 and LabVIEW 2009 and 2015. This year we have new computers and we have updated our software to LabVIEW 2016 and Windows 10. The result is that the applications has slowed down so much that it becomes useless. It takes several minutes to before the .vi runs after launching them, and it takes much more time (15-20 minutes) if you try to stop them.

 

Is there anything I could do to solve this issue? Thanks a lot in advance for your help.

 

Kind regards,

Ana+

Labview 2017 Comunication with StellatNet Blue Wave

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Hi,

I use Labview 2017, 64 bits.

1 - The "StellarNet Set Parameters.vi" send an error (show in the imagen), so I look for the file "Swdll.dll" and put it but the error continues, what can I do to solve it? 

2 - I have not been able to find information related to the way to make the connection between blocks, the order they carry, etc., in addition in the labview palette where you are these blocks there is no description about its use, neither in the StellarWave page there is information that Contribution to know how to use these tools. Someone who has a .vi that can serve as an example of how to connect the blocks?

Thanks.

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Hola,

Uso Labview 2017, 64 bits.

1 - El "StellarNet Set Parameters.vi" envía un error (se muestra en la imagen), entonces busco el archivo "Swdll.dll" y lo pongo pero el error continúa, ¿qué puedo hacer para solucionarlo?

2 - No he podido encontrar información relacionada a la manera de hacer la conexión entre bloques, el orden que llevan, etc., además en la paleta de labview donde estás estos bloques no hay descripción sobre su uso, tampoco en la página del StellarWave hay información que aporte a conocer como usar estas herramientas. Alguien que tenga un .vi que pueda servirme como ejemplo de como conectar los bloques? 

Gracias.

Using 2 different TCP/IP addresses to talk to 2 different remote servers

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Hi all,


I have an application which needs to communicate to 2 different external servers with 2 different IP addresses which are on 2 totally different subnets. So the PC on which my application resides also has 2 network cards/ports.

 

 

My question is how can I pick the separate IP addresses of my PC in my LabVIEW code to open separate TCP connections to the two external servers at the same time. (I do need to have the two connections open at the same time).

 

 

Thanks for your help!


Windows 10 and LabVIEW sys admin issue

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My users are getting the -1950679035 error when they are trying to run their application.  The Shared Variable Library is not being deployed.  The Shared Variable Library is hosted on the PC and is only used on the local PC.  All the binding properties seem to be correct.

All Windows Firewalls are turned off and the users CANNOT run LabVIEW as sys admin. 

They cannot run NI Distributed System Manager from LabVIEW.  They can from the Windows Start menu but even then it seems to have a hard time running properly.  Always spends some time in "Not Responding" mode before starting.

The OPC Server is not running and we are not using DSC.

I am not the system administrator so I can't configure Windows 10 in any way.  How can the I insure the Shared Variable Library always deploys when my users run the application?  We are using LabVIEW 2016.

 

USB-8473s compatible with SAE J1939/21?

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Hi I am using US-8473s USB can driver for one my application. i just want to know whether the this driver is compatible for SAE J1939 CAN bus protocol?

 

Can you please reply me as soon as possible

 

Thanks

Rajvel M

 

Sound wave sampling frequency problem

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Hi guys, 

I am trying to use a couple of bandpass filters on a few wav files, but I am having problems.

It works for frequencies below 4000, but anything above that I have problems. I assume it is because the total number of samples is 8000 per channel. Is there a way I can increase that to 40000?

Here the vi with the problem.

Multisim with LabVIEW

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Hi'

I am running LabVIEW 2017 and Multisim 14.1

I have followed two different tutorials regarding how LabVIEW and Multisim can work together. However, I cannot find the Multisim functions in my LabVIEW block diagram.

The Multisim icon is missing from “Control & Simulation” > “Simulation” > “External Models”. It is also missing from “Connectivity”. However, I have been able to prepare a file (.ms14) with LabVIEW-terminals, so Multisim seems to work just fine.

I assume that I am missing some LabVIEW plugin, but I do not know which one. Anyone?

Thanks in advance
Mathias

How LabVIEW Stores Variant Data in Memory ?

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Hello,

The documentation page http://zone.ni.com/reference/en-XX/help/371361P-01/lvconcepts/how_labview_stores_data_in_memory/ write to variant only: LabVIEW stores variants as handles to a LabVIEW internal data structure. Variant data is made up of 4 bytes.

I have binary data from an array of waveform, flattend as string and have to read it outside of Labview (C#, C++) . With the refered documentation I can read: ArrayDimension, t0, dt, data array.

But than come the attributes as variant.

Where can I find the documentation of the variant memory layout?

Peter

 

 

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