I have a Ham radio which I would like to communicate with through the computer.  It is as Plain Jane as you can get:

• 4800 Baud
• 1 Start Bit
• 8 Data Bits
• 2 Stop Bits
• No Parity
• No Flow Control

The radio expects 5 bytes - the first four are parameters either in BCD or Hex and a fifth Command code in Hex.  Any of the four Parameter bytes not needed are padded to provide 5 bytes, which the radio expects.

There are two commands I would like to send - one requires only the Hex command (and padded Parameter bytes); the other BCD Parameters.  Walk before I run...

1) The easiest is transferring the VFO contents from VFO-A to VFO-B.  The Command is 85 (Hex) with the four Parameter bytes padded (I tried zeros).  I had a friend create a simple routine in C++ and QT which does this nicely - so the radio works.  While I cannot see inside his exe, I presume the 5 bytes are 00 00 00 00 85.  

2) The other command is to change VFO-A to the frequency 14.250.00 MHz.  The parameters contained the frequency in BCD Packed Decimal) and the Command 0A (Hex) to complete the five bytes.  The five bytes are formatted as such:

Byte 1:  00

Byte 2:  50

Byte 3: 42

Byte 4:  01

Byte 5:  0A

Per the radio manufacturer, sent in this order will change the frequency.  But no matter what I try, I cannot even perform the simple task of copying VFO-A to B.  I have tried arrays writing within a loop, sending a string, typecasting, flattening - all examples I found online.  I don't know how LabVIEW handles data through VISA Write.  Worse, the radio manufacturer gives a BASIC example of command 2 (changing frequency) as:

Print #2

CHR$(&H00);CHR$H50);CHR$(&H42);CHR$(&H01);CHR$(&HA)

I recognize this BASIC syntax as converting Hex into String and sending them off to the Port, but cannot convert this in LabVIEW.

Yes, I use VISA Configure Port matching what the radio expects.  I think my problem is what I am feed VISA Write - I am hopelessly lost here.  I am not even sure 85H is 85 when sent as a string.  Are the 5 bytes converted to an array and sent as one string or sent in 5 iterations (if the latter, do I convert a single U8 from a byte array to a string?  If there is a conversion, what is it?

Thanks for helping the dinosaur.

John

/command1/command2/<variable>/command3-related-to-variable

one example where this occurs is with network devices port or VLAN ids  (eg:   <url>/port/3/speed    )

Obviously if it is my REST api,  I could just do /port/speed and have a variable passed for the port number  (eg:   /port/speed?port=3 ) -- but I don't get to define everyone's API... 

In my case, I am trying to emulate such behavior, so I need to setup a web resource that (ideally) would behave identically to the API,  hence  /port/3/speed  etc   is desired.  But I see no obvious way to do so in LV (2024 SP3)

I used to work with oil&gas industry which use OPC or modbus, then I work with agriculture vehicle which use CAN. I don't really know what they use to communicate between systems, instrument in bio automation manufacture or lab environment. Could you please share some information with me?

Thank you in advance!

The idea is to provide a toolkit that uses LabVIEW webservices to serve an interactive HTML5 representation of any application's front panel(s) as an easy way to monitor and control the application (over the internet) without the need for heavy applications or runtime engines. Just a browser. And because not everyone is a also web-developer, the work required to create that website should be done entirely by the toolkit. In my solution it's as easy as dropping a single vi on the block diagram, that registers the VI with the FrontPanelManager which takes care of all the data exchange between the website and the front panel.

Here's a screenshot of an example front panel showing all supported elements and its HTML version on chrome:

Obviously, there are some cosmetic differences that can be fixed later.

Controls on both LabVIEW front panel and HTML site act as controls and are synchronised across the two. By default, the website queries the front panel every 250ms for new data. The refresh rate can be changed with the cog button in the bottom right corner.

To run it

• open the project
• start the WebService
  
• Get the URL of Main.html and point your browser to it
  
• start "To Publish/Main.vi" and watch the data appear in the browser

As I said this is a proof on concept and it's a long away from being a toolkit. I'm working on functions that appear in the Tools menu to automatically add and configure the webservice and dependencies and many other things.

[2014]FPPublisher.zip

I have a development PC with labview community edition installed. On that PC an arduino uno is plugged with some sensors.

I'm trying to get some data from a sensor attached to a raspberry pi. I saw a guy on the web that connected the pi to the PC using mobile hotspot on windows and loading the makerhub firmware and getting the IP that way.
I managed to connect the pi to labVIEW and get it deploy any VI or control the GPIOs (i.e Untitled 2.vi).

The thing is that I need to run a more broad VI from my main development PC (let's say Untitled 4.vi). Now I want not only to initialize a connection to the arduino uno, but also to the pi remotely. 
I've been trying to initialize the pi with the LINX (makerhub) open module and from the drop down menu choosing the remote I/O-TCP, but coudn't get it to work.

Do I need to make any configuration to the raspberry pi from the properties meny on the Web-Server  or the VI-Server tab? Or run a server from the raspberry itself?

Which port to enter?

I dont even know if what I'm trying to achieve is possible, can anyone help me out?

Thank you.

I wonder if anyone can share some advice for me. I am working on a new project that is the pretty standard cRIO + Windows PC combination. The network topology is not super complicated and I have tried to diagram it.

The use case I am trying to solve is this: How can I connect to the cRIO and the Windows PC from my dev PC which is connected via the internet and a mobile phone network? Phrased another way, how do I assign static, internet facing IP addresses to the cRIO and Windows PC?

In my diagram all the IP addresses are totally made up, but are just to prove a point. If the cRIO is on 192.168.1.100 and the Windows PC is 192.168.1.200. As I understand I have to somehow get a static IP address from my mobile phone vendor (say the 136.154.2.75) and then modify the port forwarding on the Mobile Router so that traffic goes to the right place. What if I had two cRIOs, how would I address them independently?

Sorry, these are probably quite basic networking questions. Given the proliferation of IoT and remote monitoring devices I would assume these kinds of things are commonly solved.

Does anyone have any advice or info?

I ask for this, because in my project, communication has to remain active for several months and it has to reconnect itself to maintain the service.

delta2.vi

If anyone else would like to comment on this, please see https://github.com/ni/grpc-labview/issues/208

I have LabVIEW application as an OPC UA client connecting to OPC UA server on an ethernet port subnet which has no internet connected (128.x.x.x)

Every time I try to connect to another network (with internet) be it WiFi or another ethernet adapter, LabVIEW OPC disconnects and will not connect. While LabVIEW OPC does not connect I can confirm it can still ping the OPC server and connect using other third party clients such as UA expert.

As soon as I disconnect the non-OPC network it reconnects successfully.

I have tried changing the metric on the network adapters, changed routing tables to force the correct adapter, made the network private to no avail.

So something specific to LabVIEW is causing it to select the incorrect network interface card (NIC).

Any help would be greatly appreciated

I'm using the MQTT client by @Francois Normandin (https://github.com/LabVIEW-Open-Source/MQTT-Client) with a non-LabVIEW broker that requires credentials.

I can't find how to set username/password. Is this supported?

Cheers

What I am looking for is something that I can run on the remote PC when I am connected , such that I need to click a button every pre-determined amount of time , say 30 minutes , if I don't it can reset at least two, AC receptacles (120v,20A each). It needs to be USB or serial as I cannot , per corporate policy have a second ethernet port on the PC , there is no way around this.

I prefer an out of box solution and not a home brew device. If needed (not preferred) I can always fire a contactor with the output of the watchdog device.

Suggestions ?

Dan

I should also note that in the race instances that the certificate still appears in the Ni Application Web Server configuration (via the Internet Explorer interface) any attempt to invoke a connection using TLS is rejected immediately. A trace using Wireshark shows the connection is accepted and the Client Hello message is received from the client then the connection is immediately closed with a TCP-RST by the server. All of this had worked properly in the past. The only difference is that I am installing a new certificate since the old one expired. This certificate is valid since it works with the NI Web Server as well as a Linux based Apache server.

Processor on PC that transmits the data: Intel(R) Xeon(R) CPU E3-1515M v5 @ 2.80GHz, 2808 Mhz, 4 Core(s), 8 Logical Processor(s)   

Here is another non-free competitor.

Webpager

Here's my task.  A central HQ computer will have a GUI that monitors five machine stations, each of which has its own computer.  Every approx 10 ms (negotiable), each station gives a report consisting of two arrays, the larger being 2048 data points, the other much smaller.  Whenever HQ feels like it, HQ can tell a station to start or stop (its computer stays on).  A local IP connection is used, with a router at each end.  There is also a Raspberry Pi with its own IP address at each station's router, that can send camera frames to HQ.  The station-computers use Python and C++ to do their work, not counting whatever needs to be added to communicate with HQ.

Your advice please?  Should I use Labview?  On both ends or just the HQ?  And which if any of these helpful add-ons suggested by Hooovahh should I use?

Modbus Read 01.pdf So far 01.vi

If you want to get the host name of your machine in LabVIEW, there is a function for that:

If you want to get the host name using .NET, then you can call the method System.Net.DNS.GetHostName using an invoke node:

https://msdn.microsoft.com/en-us/library/system.net.dns.gethostname(v=vs.100).aspx

Now the fun part:

If you call each of these functions on a Window7 OS they execute fairly quickly:

LabVIEW Method: 0.000289767 seconds consistently.

.NET Method: 0.182981 first call, 0.000417647 seconds subsequent calls  (must be a cache)

Next, try the same thing on a Windows Server 2012R2 OS:

LabVIEW Method: 4.53384 seconds (WTF LabVIEW???)

.NET Method: 0.187395 first call, 0.000350523 seconds subsequent calls  (again, must be a cache)

So, let's say you are using the machine name at a unique identifier to manage a networked messaging architecture.  And as a result, you are often getting the machine name to tag a message you are sending with the sender's 'name'.  And you decide to run you system on Windows Server 2012R2 OS.  It will *work* but your performace will be down the tubes...

Any ideas on what could possibly be causing this?  I know I could come up with my own cache of the host name in my code and then access it via FGV or something simular, but that is no excuse for this dismal performance.

FWIW, there is yet another way to do this:

https://msdn.microsoft.com/en-us/library/system.environment.machinename.aspx

execution time: 7.91631E-5 seconds on Both OSes.

This leads me to the fact that a lot of the advice out there on this topic may need updating.

http://digital.ni.com/public.nsf/allkb/4B3877DB13370AA586257542003945A9

https://decibel.ni.com/content/docs/DOC-3917

http://forums.ni.com/t5/LabVIEW/Get-Computer-Name/td-p/101433

-John

but silverliight work only IE . 

how can i do work chrom app

Channel and value.vi

I am new to using LabVIEW, but have started working with the http REST client, and was curious on how I could send data to a webpage using these tools? 

Any help is appreciated. 

LabVIEW is running on 192.168.2.10 and another application(not written using LabVIEW) is running on 192.168.2.4. Application on 192.168.2.4 is configured to send the data to 192.168.2.10. So first three UPD open and last UDP open is working and labview is able to open the port on the same ip labview application resides which in this case is 192.168.2.10.

It returns error 54 when UDP open tires to open port at 192.168.2.4?

As the error stated to ping, the ping snapshot is when done from 192.168.2.10 pc.

Does anyone know why would Labview UDP open work for only localhost (198.168.2.10 same pc where labview is running) and not able to open UDP connection for 192.168.2.4?

TIA.

I have a strange problem with "Import Web Service" function in LabView 8.5. When I try call WSDL file from WS written in .NET then everything is ok. I skip the autentication, push Next and I can create Project Library. But when I want call WSDL file from WS written in JAVA I get error message "Validation Failed". I checked both WS in "StrikeIron Web Service Analizer" and in this application both WS work well.

Mayby I do something wrong. Or mayby LabView don't like WS from JAVA.

I need a hint certainly.

Thanks.

I am start working on a project require to communicate with a web service (written by another team). I have to use POST HTTP function to request access token with provide username, password and tenant name in JSON format. I use Flatten to JSON to convert a cluster to JSON string for buffer. I have connect URL as it suppose to be. I event use string constant to pass in the JSON directly, but when I ran, it returned header:

HTTP/1.1 401 UNAUTHORIZED
Date: Tue, 15 Dec 2020 04:05:22 GMT
Content-Type: application/json
Content-Length: 44
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: Werkzeug/0.14.1 Python/3.7.2

body:

{"message":"Error in Database connnection"}

The another team told me to test with Postman and it run fine with the same input URL and JSON data. It returns the correct access token.

I am not sure what the different between my labVIEW code and the Postman structure. 

I don't have much experience with HTTP and Web service through so I ask for your inputs.

Thank you very much in advance.

EtherNet_IP_PCCC

Use these set of VIs to communicate with MicroLogix Series PLCs Via EtherNet.

These VIs use simple TCP/IP Communication.

Communication : Ethernet, TCP/IP

Protocol : EtherNet/IP

Service :CIP (For Connection Management), CIP Service for PCCC

Command : PCCC

Tested with : MicroLogix 1100, MicroLogix 1500,1200(with NET-ENI)

No OPC Server Required

No Automation Server Required

No NI-DSC Module Required.

Note: These VIs access N7 Integer File. To access other Files in the PLCs, just replace the "Fileno" Constant(0x07) with a Control and make it as a parameter to the SubVI.

EtherNet_IP_CIP

Use these set of VIs to communicate with CompactLogix, Control Logix Series PLCs, Any Device that supports CIP(EtherNet/IP)

These VIs uses simple TCP/IP Communication.

Communication : Ethernet, TCP/IP

Protocol : EtherNet/IP

Service :CIP (For Connection Management, Read, Write)

Command : CIP Commands

Tested with : Compact Logix Series PLCs

No OPC Server Required

No Automation Server Required

No NI-DSC Module Required.

Visit : ODVA Website for EtherNet/IP Protocol Specification

I am trying to send a simple message to an Azure IoT hub. I am pretty new to all this, but have followed a few tutorials and Pluralsight courses and can successfully send a message from VS Code to my hub.

What I have not been able to do yet is send a message using LabVIEW. I have tried several different MQTT libraries, without any success. Has anyone done this kind of thing before and can offer guidance on which toolkit they used?

I am using VSCode to generate the SAS token and using that as the password.

Edit: I have been able to send some messages using simple C# code, this code works fine.

Thanks

Hopefully someone here can shed light on the why authention with the LabVIEW HTTP Client VIs isn't working.

I've heard that you need to register the SSL? Does anyone know more on this?

Thanks a bunch.

first of all: I'm new to web server in general (non only labview web server)! Starting from the official examples now I managed to realize very simple web server with two methods and SSL communication enabled; it' only a small test that I'm using to understand the basic, than I will create the fully featured one and implement it in my main application.

I'm stuck with the authentication aspect of the web server. I was able to create a group and a permission, set a specific method to accept communication with this permission (auth with username/pw); but my understanding is that, choosing this type of authentication, only request from Internet Explorer (the only browser that's still supporting Silverlight) or from a LabVIEW client will work. In the final application the request to the LabVIEW Web Server will be performed from a client coded in python.

Now I'm trying to configure a LabVIEW Web Server with API-based authentication. Unfortunately, even a simple LabVIEW client cannot successfully communicate with the server. Here you can find some screenshot of the LabVIEW WS settings, the web-based Configuration and Monitoring, the block diagram of the client and its front panel with the reply from the web server.

The LabVIEW client works fine with the same GET string when the server has no authentication or the username/pw. When I try to use the API key solution the response to the client from the server is 403 - Forbidden.

Any help?

Thank you very much!

Marco.

Web server - security of the method getDynamicData. "Require API key" selected.

Web server. URL Mapping of the method "getDynamicData"

Web-based Configuration and Monitoring. Web services API key

Block diagram of the LabVIEW client

Front panel of the LabVIEW client

This all is to say I keep coming back to the concept of using MQTT locally as well as remotely and bridge the brokers, much of the logic is in place or could expand to fit the local requirements. The local communication would handle commands and tags/current values between systems and the brokers would package a subset of that to be sent remotely. This blog post from 2017 gave me some inspiration.

Has anyone gone down this road and has any feedback or suggestions pro/con?

I have here a LabVIEW 2014 project which was compiled into a .NET Interop Assembly.

Now I try to activate the LabVIEW Remote Panel Server for the assembly.
Apparently it seems to be active.
But for every VI i get the message that it is not in memory.

But I am sure that these are in memory.
When I compile the project to an executable, everything runs fine.

Does anyone have a hint what I am doing wrong?

the content of the ini file (InteropAssembly.ini):

[InteropAssembly]
server.app.propertiesEnabled=True
server.ole.enabled=True
server.tcp.acl="290000000A000000010000001D00000003000000010000002A10000000030000000000010000000000"
server.tcp.enabled=True
server.tcp.port=3361
server.tcp.paranoid=True
server.tcp.serviceName=""
server.vi.access="+*"
server.vi.callsEnabled=True
server.vi.propertiesEnabled=True
WebServer.Enabled=True
WebServer.TcpAccess="c+*"
WebServer.ViAccess="+*"
DebugServerEnabled=True
DebugServerWaitOnLaunch=False

All you need do is put a TCP/IP listerner in your diagram and return this handshake as described in the wikipedia article on WebSockets. Once the connection is made, you can stream bidirectional data between your LabVIEW application and any bleeding edge browser (Firefox 4, Chrome 9, Safari, IE9?). You can use the DOM to set the transform attributes of SVG elements using the streamed info (rotate, scale, set heigh, width, line points, etc.).

Now that we can all design our own GUI objects using Inkscape (free), I suggest a concerted effor to develop a standard SVG format, streaming protocol (based on WebSockets) and open-source script library. The very best thing about this is that it is all FREE, and runs on any platform that has an HTML5/SVG/WebSockets supporting browser (I'm keeping my fingers crossed for the next firmware revision of the Nintendo DSi), and requires NO PLUGINS. So all you folks with iOS and Android who feel left out by the WebUI Builder, or those of us who are infurated by it's $1500/yr price tag (after spending $ on LabVIEW RT/FPGA), Cheer Up!

Here are some screenshots of my efforts. The files are opened in the OS, but will also work when served by the old-fashioned "non-webservices" LV web server (you gotta add an SVG mime type to the mime-types file).

You can also use RGraph Library and the HTML <canvas> tag if you want to implement a non-SVG browser solution. The library is free for non-commercial use.

I suggest a community effort the create the standard SVG formats for UI elements, and a free, open-source ecmascript library for handling the messaging and DOM animation tasks. If there is interest, I will upload my script as a starting point, but I must warn that there is much improvement needed.

sm

I don't see any discussion of zeromq on lavag, has anyone got experience of using the labview version - http://sourceforge.net/p/labview-zmq/wiki/Home/ ? It would be comforting to know it had proved to be reliable and scaled ok before spending any more time on it. I'm encouraged by some prototypes i've written for fault tolerance.

Would welcome any experience with 0mq and other suggestions for simple networking without going completely back to basics.

Cheers bob, uk

I have just started to play around with the Web Module in NXG 4.0. There are quite a few tutorials around, but (unless I have missed something) all of them seem to gloss over the task of getting a trivially simple web VI actually running locally. After a bit of head scratching I did manage to get something up and running eventually, but have a question which is hopefully simple for anyone who has used the Web Module.

When running the web VI inside the NXG IDE, is there anything actually hosting it? In other words can I visit some address from my web browse to see it running while I am developing it? Or do I have to build (i.e. turn into html and JS) and then copy the files manually to my NI Web Server directory?

The use case is an operator wanting to trigger an action that is approved by a supervisor on a mobile device. Offline authentication would be very helpful too.

I use shared variables on several projects on different nodes. On some of them, after rebooting the OS, the variables restore their value (as it should be), on others this does not happen. I use Windows 10 and approximately the same setting. Does anyone know where I can search in the OS settings or LabVIEW to get predicted DSC behavior after rebooting the OS.

Sincerely, Vitaly.

I wonder why my CAN Arb. ID is different when I'm using NI MAX Bus monitor (1700E701) and ncReadNetMult.vi (3700E701). The system is working with extended ID. 

I'm supposedly retired, but then decided to go over to the Dark Side and become a contractor.  We'll see how long that lasts...

Current issue:

A C developer and I are sending data via a MS loopback adapter between a C app and a LV app on the same machine (Windows 10).  Past iterations have worked great (after that little bug in LV11 was fixed).  The new system, however, needs a much higher continuous data thruput -- somewhere in the neighborhood of 900 MB/s.  The loopback adapter is topping out somewhere around 500MB/s. 

If we switch from internal TCP to connecting two 10G NICs in the same box, the data gets passed with no problem.  So it's not the code, and we know how to configure hardware NICs for large data thruput.

We've tried everything the web seems to offer, including a lot of things that have been supposedly deprecated.  We've tried using localhost, 127.0.0.1, a 192.68 address, and various other IP addy options. If you google "how to speed up a loopback adapter" or any variant of that, we've probably tried it.

Does anyone have experience with tweaking a loopback adapter and have any suggestions of things to try?  If it matters, the computer is a screaming fast dual Xeon with 128 GB of memory.

Cat

This is my first post on this forum as I just learned about it and am fairly new to LabVIEW as well as the whole NI environment. I was at NI Week 2019 and was very impressed by the size and the quality of this community.

I am currently working on building a test rig where we'll be doing HIL testing as well as dynamic load control. Basically, our first target (PXI-based) will be running VeriStand and dedicated to doing data acquisition and HIL. Our second target (still PXI-based) will be running LabVIEW RT 2018 and dedicated to performing load control. The first target will be equipped with a reflective memory module to share data with a third-party test infrastructure and a host-PC where the data logging will take place. I need to send over some data from the 2nd target (LV, load control) to the 1st target (VS, data acquisition and logging) as that data needs to be populated to the RM and logged. We're talking about 32 floats, double-precision, that I need to send at a rate of 200 hz.

1st option: buy a RM module for my second target and populate data directly from that target.

2nd option: send the data to the 1st target through Ethernet using "some" protocol.

The first option seems straight forward, but definitely more expensive.

The Questions:

1) Regarding the second option, I'm not sure how to implement that. To share data from a LV target to a VS target, would that be done through UDP, TCP, network-published shared variables, or another protocol?

2) As a side question, can I connect my two (2) targets + my two (2) host PCs (1 host for data logging, 1 host for load control) through an Ethernet switch? Then, use my data logging host to communicate (GUI) with my 1st target and my load control host to communicate (GUI) with my 2nd target?

I am looking for a way to find controls on an executable LV program. 
I need this function because I want to automate a series of tests (user mouse clicks for example) on an executable LV program.

The normal tools who does it with windows objects are not able to recognize LV controls individually.

My idea is to find a way to recognize LV controls so I can interact with them individually.

If anyone knows any third party programs to do automation tests for a LV exe that would also be highly appreciated.

Best Regards,
Vlad

Error 363507 - LabVIEW could not verify the authenticity of the server

Shown below, this code demonstrates the issue. The 'workaround'? Set the 'verify server' flag to false.

Shown at the bottom is a simple HTTPS connection to Google works no prob -- could this indicate a misconfiguration on my web service?

Any ideas? Thanks!

Info on ARP from Wireshark.

Has anyone gone down the road of evaluating or has experience implementing the OPC UA architecture? There are a couple of toolkits out there so thankfully there is no real need to tackle the OPC .NET API. At this point I'm trying to fetter the tech side of it. What were the unexpected roadblocks you ran into?

If anyone can share their experiences it would be appreciated.

Thanks!

Password protection of VIs has been removed.

https://github.com/NISystemsEngineering/LabVIEW-Modbus-API

I am trying to send email in LabVIEW with Asian character.

No matter what I try, only the standard character are sent.

Is anyone succeed in this?

Thanks

Benoit

I have remote application (i.e. telnet server) using command prompt I use telnet client for example telnet 127.0.0.1 9001 and sending command to the application. And it works fine but I want to use labview based telnet client using TCP to send command to the remote application.  

By using command prompt (telnet client) i can send command directly to the application, but I have tried with TCP and it can't give me proper output please find below code snapshot and please reply.

Thanks

Pravin

I am looking for a functional MQTT server client implementation for Labview. I have been doing some search, and found something, but they all seem to be unsupported. Does anyone have any pointers to a fully functional one? Is NI developing any stuff on this?

Thanks

Edited for correct content

I have a project that I am working on. It is running on an old machine using Windows XP, and LabVIEW 8.6.1. Our customer has requested that we add the capability to make a call to a web service that they have written. They do not want to upgrade the OS or LV version, so I am trying to find a way to do this in 8.6.1. They have given my the wsdl file to review and it is specifying using the SOAP protocol in a request/response format. The request message, requires 5 pieces of string data from the LabVIEW application. I have never done any web service calls before in any language so I am trying to learn that as I go as well. I have tried searching on the forums on how to do this, but I have not found anything. So I would like to know if there are any VIs in 8.6.1 to support this kind of request. If there are, can someone please tell me which VIs/pallet to use and some guidance on how to use them?

Web Server.zip

First off, I'm very new to LabVIEW and programming in general, so let me apologize in advance for my knowledge deficiencies. I'm working with a device that I can talk to with serial communications or via telnet. I developed a set of VIs that allow me to specify which method I'd like to use for communications (serial or telnet) and then open, read, write, or close the connection using either the VISA VIs or the TCP VIs respectively. I ran into an issue in that I didn't know the amount of bytes to read for the TCP Read VI because the device I'm talking to has a very large list of possible commands (and the response length may change at the whim of a developer), but I found a neat solution here. This last detail becomes important later.

Anyway, everything seemingly worked great within the LabVIEW development environment. Then I had to rip an executable for an end-user. From the executable telnet doesn't work at all. Worst of all, I don't seem to get any sort of error out. In trying to resolve this issue I did some Googling and found the following post suggesting that the issue might be that the VI that opens the telnet session needs to keep running. I also found this post and I think rolfk's answer gets at the root of my problem ("Just be aware that LabVIEW garbage collects all its refnums as soon as the hierarchy that opened that refnum goes idle"). As far as I can understand, my issue is that as soon as my subVI that opens a telnet session finishes the refnum it returns in the form of a TCP connection ID (to be used by the write, read, and close VIs) gets trashed. So I try creating a little test VI where I use the TCP VIs all within a single block diagram and it seems to work fine as an executable. This gives me a potential solution, except that, as I indicated above, I don't know the number of bytes to read for the response to any given command and have been using the TCP Get Raw Net Object VI as part of the solution to that problem.

I guess my question is, how can I keep the VI that opened the telnet session running (and not just in memory)? I'm content to move the TCP Open VI out to an upper-level VI (and have all read, writes, and the closing of the session handled in a subVI), but the calling VI seems to suspend as soon as a subVI starts executing. I've tried digging around in the execution settings within the VI properties, but nothing there seems to be what I'm looking for.

Alternatively, I've considered using the VISA VIs to handle the telnet session. The only issue I have with this is that I still need to know the number of bytes to read. I think I could use my current solution provided that I can typecast from a VISA resource to a TCP connection ID (as the TCP Get Raw New Object VI expects). I've done some reading that indicates this is possible, but I haven't been able to figure out how to do it.

I greatly appreciate any help anyone can provide with this issue.

I have downloaded LabbitMQ, but I'm assuming that won't work with Apache Qpid?  I was hoping that the whole open standard thing meant that different implementations of AMQP should be able to talk with each other, but the following link regarding interoperability between the two seems to say that this often isn't the case.

There is a Native AMQP client for LabVIEW  on GitHub, but it is missing all the vis (at least from what I can tell), so isn't much help.  I posted an "Issue" to the Repository, but don't know when/if I'll ever get a response.

Any thoughts/comments/suggestions? 

Cat

I see this error every now and then on various computers. LabVIEW hangs in the task bar and I have to for quit and then I have to restart the NI PSP service and everything is OK. I have a service ticket open but we're sort of running out of ideas for how to reproduce the problem or on what data we can gather when I see this error.

I'm trying to use AMQP protocol to send data from a CRIO.

I've tried using LabbitMQ and zeroMQ libraries, and when I test it from my computer (windows), it works with no problems.

But when I try to put the code on CRIO, there's a lot of errors caused by broken wires. It looks like a .dll or .NET incompatibility.

Is there any compatible library for CRIO or some clues about how to make it works?

• Autoapprove the exception as part of installation
• Is there a way to keep prompting them until they approve the exception or close the app
• Maybe a command line I can send them if they say they are seeing error 56?

Thanks.

After years of managing to avoid LabView and the Interwebs, somebody got the great idea of running some of my code via a web browser. Sure! I say, LabVIEW's got stuff to do that!  Three hours later and it just ain't working right. I've read all sorts of things like:

http://zone.ni.com/reference/en-XX/help/371361M-01/lvconcepts/ws_distributing/

http://zone.ni.com/reference/en-XX/help/371361L-01/lvhowto/enabling_the_web_server_in/

http://zone.ni.com/reference/en-XX/help/371361M-01/lvconcepts/ws_web_server/

http://zone.ni.com/reference/en-XX/help/371361M-01/lvhowto/build_web_service/

etc., etc.

They just don't seem to be fully addressing my situation. Unfortunately there doesn't seem to be document that goes thru it all from start to finish.

Here's my setup:

Computer A: Running a LabVIEW application -- call it TestWeb.exe

Computer B: Running Explorer/Chrome/Firefox. No software can be loaded or installed on this computer, including any NI software.

Is there something I can do to be able to view/control TestWeb.exe, via a web browser, from Computer B?

I've gotten it to work wonderfully -- using source code, but even tho I think I'm doing what the various docs say, it isn't working with an executable. Are there more complete directions somewhere someone can point me to?

Cat

There is / are bug(s) in my implementation and I may need help to get to the core issue.

This is the VI hat I am running as seen from the remote unit (PC / tablet):

In the above image, the controls of interest are Selected Room, Calibrate, Microphone, and the year (duration) selector.  The indicators of interest are Serial Number, Mfg Sensitivity, Calibration Data, Measured Sensitivity, the graph and the other items on the right..

What works..  Well, when I click on Calibrate, it seems to activate it on the running VI.  But it does not update the display.

Thank you.

with these files, I want to be able to also upload the correct metadata.

all of the metadata will already be loaded in the program, i just need to upload it.

don't know if there is any topic about that on the forum already, haven't found it yet.

Thanks a lot for reading this post and being able to help.

I would like to know what is the most recent release of modbus library for Labview. Which version?

1.1.5.39 of this link http://forums.ni.com/t5/NI-Labs-Toolkits/LabVIEW-Modbus-API/ta-p/3524019

or

1.2.1 of this link http://www.ni.com/example/29756/en/ ?

Thanks a lot!

Client closed connection (normal disconnect)

Some one pulled the cable (can blame user)

Client thread crashes (can blame client developer)

I am also surprised that there is no "button" in the controls selection.  Do we need to use a shape and assign it as a button?

Is there something better than the Data Dashboard?  I am unimpressed with it.  NI really didn't seem to get this one right (at all).  The software crashes whenever I switch from the Data Dashboard to another app and return to it.

I need to create a small application that will allow the user to start a process remotely.  It should be really simple, but the Data Dashboard is not cooperating. 

Using:

Samsung Tab S2 (latest version) Model: SM-T817W

Kernel Version:  3.10.9-8493064

Android Version: 6.0.1

Is there other info that is needed?  I can't share code because, well there isn't any.  The only screen capture I could show at this time would be a blank white page.

Thanks,

RayR

I'm particularly interested in Kademlia/S/Kademlia and Chord so would appreciate any input specifically about those, but any other DHTs that have been played with would be great for discussion.

Firstly I am very new to labview so i apologise in advance if i ask some stupid questions.

i am running a vi on my rio ( simple analog in/out express vi s) and another vi on my PC. i am communicating between them through shared variable and it works perfectly, only thing is i have to manually run both vi s.

my question is, is there a simple way to start the vi on myrio from the vi on my PC? 

PS:- i tried to work with vi server but i failed because of my limited knowledge. 

any help will be much aprreciated.

Thanks & Regards,

Parth

I build a Vi to perform serial comm to test the visa info.

First, I test this vi at virtual ports ,comm1 for serial program, comm 2 for this vi,one for transmission and one for receiving. OK!

but when I use it at single Comm3 (Prolific USB serial port,MAX's view is OK) and loopback ,I got

I Don't figure out what's the problem, Could Give me some advice? Thanks!

serialnew.vi

I am trying to create a VI that will create an event and will sync it with my google calendar.
I have looked online a lot and found nothing about this topic!

I found some examples that would allow me to send e-mails to my gmail account, but I couldn't figure out how to create a calendar event.

Any help/guidance will be highly appreciated!

Thanks in advance,
Vlad 

Currently here is what I am doing:

• On first call, open the application reference and then open the VI reference.  Cache both of these.  Use the VI reference to call the remote VI.
• On subsequent calls, test the cached references to verify they are still valid and then call the remote VI.

What appears to be happening is the references still appear to be valid in the caller but the connection is broken so the remote call fails.  Then I detect this and reopen the app and VI refs and can again call the remote VI.

The issues are:

• The failing remote call takes a long time to timeout and I do not see how to control this timeout.
• The test of the refs does not actually test to see of the network connection is still good.

The result is it takes a long time to recover and this is upsetting the user since it appears the system is locked up.

What I need is a way to control the timeout of the 'call by reference' node or a way to quickly test the references to verify the network connection is still good before I attempt the remote call.

Any ideas?

thanks,

-John

I am currently developing a scope that displays live data from a test rig. The scope is accessible via remote panels. Tests normally run for many hours at a time, when monitoring the scope after several hours of running I notice that the data on the chart displayed via the remote panel is not in sync with what can be seen on the actual 'server' vi. The delay also seems to be getting bigger as time goes on. I also display the current data points in an indicator; however these seem to be in sync and 'current'.

The scope is part of a built application and I am using labVIEW 2012 f3 to develop it.

I know that there is an issue with synchronizing front panel appearances when using remote panels in built applications but I think I have got around that by re-applying panel changes when a new client connects. Also on every execution of the VI, I defer panel updates make all my updates to controls including the chart in question, force draw the chart and then re-enable panel updates.

I would really appreciate if anyone that has experienced this sort of issue could share a possible solution/work around.

Thanks in advance.

First is the system:

Now I shows my steps

And this is the disappointed result

I am doing the thesis with this. so I need your help urgently :'( 

Thank you in advance

The problem comes in when I try to open a connection to the remote machine by name using the Open Application Instance function.  It will try to resolve the name to an IP internally and then connect.  But if the DNS give it the local (home) IP first then it will fail to connect since that IP is not part of the office network.  If it give it the VPN IP first then it will work.  The problem is I have no control over which IP it will see.  And apparently it does not try all of them, only the first one.

Does anyone know if there is a way to control this?  I need to have it give me the local (LAN) IP if there is no VPN connection and the VPN IP if there are two IPs.  And I need it to be deterministic, not random.

thanks for any ideas,

-John

I am perceiving some strange behavior in my UDP connections. Every time I re-start my cRIO 9063, the UDP Write block outputs ERROR 66 (LabVIEW:  The network connection was closed by the peer. If you are using the Open VI Reference function on a remote VI Server connection, verify that the machine is allowed access by selecting Tools>>Options>>VI Server on the server side.) and it does not transmit. 

The most bizarre thing is that if I simply stop the execution and re-launch it again (given that I am executing the code of the cRIO in Debug mode from a Windows laptop), the UDP connection behaves perfectly well. The only time it fails is the first time I launch the program after I reset the cRIO. For me, it looks like some service is not properly initialized when the cRIO is started.

I attach a picture with the UDP connections of my LabVIEW RT program. The 'Comms RX' VI simply calls the 'UDP Read' function, and the 'Comms TX' calls the 'UDP Write'. The 'Open UDP Conn' also simply calls 'UDP Open'. 

Can anyone help me?

Has anybody used the OPC UA client that is part of the DSC toolkit? I am trying to use it to connect to a PLC and am getting error -336653 "The status of the OPC UA server is uncertain"

I am able to create a local OPC UA server in LabVIEW and connect to this with no issues from the LabVIEW OPC UA client, and can connect to the PLC just fine using a different client.

After speaking with NI it looks like this may be a permission issue, but I have tried all the obvious things in the OPC UA client (like client and server certificates), with the same result.

Any tips?

Crossposted 

http://forums.ni.com/t5/LabVIEW/OPC-UA-client-cannot-connect-to-PLC/td-p/3195246

I already readed this:
http://muree.psut.edu.jo/Documents/DEV4.2-Services%20Adaptation%20to%20Connect%20Remote%20Labs%20to%20VLE-Securing%20WS%20in%20LabVIEW.pdf

http://www.ni.com/white-paper/7749/en/

How i must encrypt my body through java? What happened with data when they go to Encrypt Vi?

Thx for ur help

I have one devie which is used for monitoring the water leaking in my project. But the data of this device is only monitored in web browser, which is not compatible with our software frame of labview. The vendor of this device only provides the MIB file of SNMP protocol. If I want to integrate DAQ system of this device in our software frame of labview, are there good ways? Or who sends me the free SNMP Toolkit of labview?

My E-mail is zyh7148@yahoo.com.cn

Thank you!

- Be as close as possible to the functionality, operation and semantics of the built in LabVIEW library

- Support IPv6 operation

- Support SSL encryption

- Support ping operation right in LabVIEW (through use of raw sockets)

- and of course be better than the built in functions

The included library does most of these things already but will need some more work over the next few months to fully have all these features. As such it is clearly in a preliminary state and not yet ready for released software. Please be adviced that this library will cease to operate after end of June because I expect to have new releases out there before that time.

In spite of the preliminary state it does work and does do already quite a few things and it even implements the LabVIEW TCP read modes exactly as the native functions.

I have included an OpenG package of the library. To install it you best use the VIPM application from JKI Software as it will take care to place everything where it should be.

Due to some features I'm using it will be necessary to restart LabVIEW after installation of this library in order for the library to work properly.

When installed you should see a new ESI-CIT logo in the main function palette and in there a network icon. In that network palette are all the new and exciting functions. The functions have for a large part already some online help information inside, which you can see by opening the floating help and hovering over the icons or front panel control elements.

I'm working on an online help file to install along with the library but it is not yet finished. This help will also outline some of the more low level operations which at the moment may appear a bit obscure.

This release is only for Windows 32 Bit systems. Sorry to the Linux and Macintosh users but porting such a library is a true pain in the a** and especially for the Macintosh I'm not yet sure how to go about it, as there are several ways to skin that cat

The library will work in LabVIEW 7.1 and newer versions.

readme.txt

citlib_lvNetCon-0.9-1.ogp

Can anybody shed some light on some strange behaviour I am seeing when deploying an executable with Web Services and Public Content.

I have an HTML page that gets served up as part of my application. My LabVIEW application interacts with a browser via Web Services.

Everything runs (mostly) fine, I can browse to localhost/ws/index.html and I get my web page.

However, I would have expected that HTML (and JavaScript etc) would remain on disk in source form so I could edit it after the LabVIEW application has been built, but this does not appear to be the case. Changes I make to the source do not get reflected until I rebuild my LabVIEW application.

Does the Public Content in the Web Service get packaged into either the .exe or the .lvws up as part of the build process?

I am really perplexed by this. I have tried all the obvious things like clearing browser caches etc. I even tried using a brand spanking new browser that had never been installed on my PC and I got the same symptoms.

I am making a basic programme for fall detection for the elderly. Right now, face detection is employed to identify a face, and should it fall below a certain level which can be adjusted, a warning light triggers. Using the smtp email example in labview, i have gotten the thing to send an email.

However, what i want is an automated sending of email when the warning light triggers and when it has been lighted up for say a min or something like that. Here is how my programme looks like so far:

The specific section of the email part in question:

Any ideas?

First, a little background on the application:

In my system, there are N servers running on the network.  Each of these is running on it's own VM with a static IP and unique machine name.

There are also N clients.  These are running on physical machines, VMs and a Windows RDS (Remote Desktop Server).

The messages are all abstract class objects.  Both client and server have a copy of the abstract classes so they can send/receive any of the messages.

My current solution is to use VI Server to push messages from one application to the other.  There is no polling.

Clients and servers can go offline at anytime without warning and the application at the other end of the connection must deal with the disconnect gracefully.

In normal operation, the client will establish connection to a group of servers (controlled by the user).  The client provides it's machine name and VI Server port.  Each server then connects back to the client.  All messages then pass via these connections.

Therefore, a client is uniquely identified to the server by its network machine name.

Now the problem.  A Windows RDS session does not have a unique machine name.  Instead it uses the machine name of the RDS.  So, if two users run the client application in two separate RDS sessions at the same time, when they connect to the servers, they will look like the same machine.  There is no way to uniquely identify them and route messages to the correct one.

So, I have started looking at network streams as a possible solution.  They looked interesting because you could add a unique identifier to the URL so you could have more than one endpoint on a single machine.  This looked like it would solve my problem because I could combine the machine name and user name to make my client endpoint unique.  But here is the process I would need to follow:

• Server creates an endpoint to listen for client connections.
• Client gets the list of server names (from a central DB) and then tries to connect to each server's endpoint.
• If successful, the client creates a unique reader endpoint for that server and then passes the server the information about how to connect to this endpoint.
• When the server connects to this endpoint, it also creates a unique reader for the client and sends that info.
• The client connects to the server using this unique endpoint and we now have two unique network streams setup between client and server, one in each direction.
• The client then disconnects from the first server endpoint since it now has its own unique connection.
• Both ends will need to have some sort of loop that waits for messages (flattened class objects) and then puts them into the proper local queue for execution within their application.
• Both will also need to be able to send a shutdown message to each of these loops when exiting to close the connection.

My concerns are how to have the server listen for connections with its generic endpoint to multiple clients at once.  There is no guarantee that only one client will try to connect at a time.  And once the client is fully connected and releases the generic connection, will the server be able to listen for more connections or will that endpoint be broken?  How do I reinitialize it?

This is all so much easier with VI Server that I might have to just give up on the RDS solution altogether.  But I want to give this my best shot before I do that.

Thanks for any tips or ideas or pointing out any pitfalls I missed.

-John

Cat

Hope to hear you guys soon. Thank you.

I can authenticate, but my Salesforce IT guy tells me that Salesforce uses a concept called "upsert". It's update and insert combined; but I need to use the PATCH Method instead of a PUT or POST method.

I can't seem to find any reference to the PATCH method.

I believe the LabVIEW library uses curl under the hood.

Anyone have any ideas?

HEADER:

BODY:

[{"errorCode":"METHOD_NOT_ALLOWED","message":"HTTP Method 'POST' not allowed. Allowed are GET,HEAD,PATCH,DELETE"}]

• Compile code into the web server. This option is more difficult to reuse, as you're making a plugin for a particular server, but some servers can use plugins for other servers.
  
  • Apache has modules, for example mod_perl which is basically a dll which runs perl.
    
  • IIS can run all sorts of .net code and scripts
    
  • I *think* this is what LabVIEW has done for its web service, but can't confirm.
    
  
  
• Use a protocol between the front-end web server and the back-end application.
  
  • The simplest version is CGI -- the web server runs an exe, passes any post data as standard in, and waits for data on standard out or standard error. This is slooooow as it runs an exe every time.
    
  • This was improved with FastCGI where the web server launches N copies of the exe on boot and then leaves them running. These EXEs are sent packets which correspond to the CGI standard in data and respond with standard out and/or standard error packets. These packets can be sent through standard I/O (which is tough with lv) or through TCP (which is easy).
    
  • Some people use a simpler HTTP server running in their program as the back-end. It can be simpler and less robust than, say, apache because in theory you're only getting well-formed packets from the front-end http server.
    
    • Compared to FastCGI this can be even faster because the HTTP request doesn't have to be re-packaged into an FCGI request, but HTTP is single-threaded (for lack of a better term -- requests must be responded to in the order they were received). The other advantage is you can use a web browser or other http client to talk directly to the simple http server, which you can't do with FCGI (for debugging purposes). This is essentially a https://en.wikipedia.org/wiki/Reverse_proxy
      
    
    
  • There are some custom protocols used like WSGI which seems to be python-only, or things like java applets.
    
  
  

Any ideas how to get either browser to work for remote panels?  I'm at the end of my rope with this one. 

Also - I have tried from 2 different computers on the network with the same results so I assume it is a problem with my real time web server configuration?

like this

The first release of our website www.wezarp.com is now online !!! Wezarp for NI LabVIEW is available... Don't hesitate to download and try the 30-day free trial version !

Here is a video demonstration on how to use Wezarp with NI LabVIEW

I tried to use some old  examples using .net (google API) but not run.

I think that google change API version and the examples not run.

Tanks

I couldn't find the folder where I could do these things in the file structure of the 9068. Has anyone had any experience regarding this?

I have a problem with http VI’s and external web services (RESTful) and I’m using LabVIEW 2013.

In NetBeans I create a project with a GET web service from a table in MySQL, so I use http VI’s for accessing the service (blog diagram .png), receiving the information in JSON (front panel.png) and took the information I needed (in this case the “slActualValue†value).

I have a program that inserts new values in the database and in chrome the service works fine but if a want to do the Vi in a while loop to update or receive new values, the the next JSON data form the web service is the same as the first call, but if I go to the NetBeans project and do the deploy again the JSON data changes.

I ask about this problem from the experts in web services (RESTful) and they say that is the cookies in the LabVIEW program, so I create add a cookie file .txt but im not confident about the format of the file(the example is in this post) or if there something amiss in the LabVIEW VI’s

Cookie.txt file

# Netscape HTTP Cookie File

# http://curl.haxx.se/rfc/cookie_spec.html

# This file was generated by libcurl! Edit at your own risk.

UNKNOWN        FALSE    10.18.9.32:8080/arto      FALSE    0             ID           0