Array of string to a shared variable

Similar Questions

• OR shared Variable engine usage example

  Hi guys,.

  using OR shared Variable engine and we try to use it with java. As we understand it, NOR shared Variables are available on the network.  So it is possible to communicate with the use of Sockets. Is there a protocol that I have to use? Any of you got an example on how to write a string to the shared variable?

  Hope this is the right forum.

  Thanks in advance.

  Greetings

  Tuney

  According to this link: http://www.ni.com/white-paper/4679/en/

  "In addition, with the network library Variable introducted in NI LabWindows/CVI 8.1 and NEITHER measure Studio 8.1, you can read and write variables shared in ANSI C, Visual Basic .NET, or Visual c#."

  There is also more information available on the following links:

  http://www.NI.com/white-paper/5484/en/

  http://StackOverflow.com/a/4597966

• How to make a shared variable, which is an update on the host channel?

  Hi all

  I'm relatively new to LabVIEW, so I apologize in advance.  I'm working on a vision for research application and I'm trying to convey an image of the smart camera target to the host.  I flattened the IMAQ image to a string and pass the string to a shared variable.  On the end of the host, I unflatten image and try to post to see if I don't really get the image data on the host.  However, it only displays the first image and after that the image is not updated.  In addition, the shared variable itself is not up-to-date.  I have a loop timed on the target and a loop of simulation on the host.  Help or direction would be appreciated.

  Thank you very much.

  I thought about it and will post here just in case it might help someone else.  For some reason, the IMAQ flatten channel gives a format that did not like the unflatten of the chain.  When I have no flat chain, it didn't recognize it as an image.  Instead, I just used the generic flatten the string on the target and then block when I have not flattened image on the host computer, I had to only give the guy I got to report the allocation of memory IMAQ.  Maybe I'm just slow, but if this helps someone else, fine.  Thanks again.

  mkillpack

• Passing an array via one RT FIFO network shared Variable, Code error-1950679034

  This should be simple.  I'm just passing through a table via a single RT FIFO network shared Variable element.  And yet I get nothing.  How could - not working?  What is this error?

  

  Well... it must have been some sort of thing calendar because adding an expectation of 100 ms fixed it straight up.

  Now don't feel ridiculous

  

• shared variable

  Hi all

  There is problem of variable shared with twine, there is table if the variable sharing chain and an array of string is not updated

  National salvation...

  Please give us more information. Can you show the problem with an example vi?

  Mike

• An array of strings as function parameter in loop fails

  Hallo,

  I have a weird problem here and I hope someone can help me find the cause.

  I have a function where I said an array of strings (string_list). I pass the array to a function that does modifactions to the table. I am addressing Walker the array of strings to an index of all the values are stored correctly. When I loop through the array by incrementing the index automatically only the last index value are saved in all positions.

  Why is this? Or what I am doing wrong?

  It is the passage to another function, an array of strings
  
  int calling_function
  
  {
  
        char * string_list [MAX_PATHNAME_LEN];  //< store="" strings="" in="">
  
        function_called (string_list);  passing a pointer to an array of string
  
        return 0;
  
  }
  
  This is the function receives a reference to an array of strings to store data
  
  int function_called (char * output_list [])
  
  {
     int i = 0;  counter variable
  
     / * This works and good values are stored in output_list * /.
  
      output_list [0] = '02 ";
  
      output_list [1] = '12 ';
  
      output_list [2] = "22";
  
      output_list [3] = "32";
  
      output_list [4] = '42 ';
  
      output_list [5] = "52";
  
      output_list [6] = '622 ';
  
      output_list [7] = "72".
  / * This does not work and will store '31' in all places of the matrix * /.
  
      < 32="">
  
      {
  
          < %d »,="" i) ;="" incrémenter="" la="" valeur="">< br="">
          output_list [i] = sample;  < br="">
          i = i ++ ;                   < br="">
      < br="" >="">

  output_list [0] = '02 "; < br=""> output_list [1] = '12 ';< br="" >="">

  Thanks!

  Hi,.

  When you do

  output_list [i] = sample;

  all of the members of the array have the same value: sample-a char pointer. You are modifying the afterwards glad of sample purpose the previous values still point to sample.

  If you assign values to each array member like:

  you assign different values: a pointer to a string containing "02", pointing to a string contaning "12",...
  If you want to assign values in a loop you need to allocate memory for each string (output_list [i]) and copy the content of sample in them.
  Does this make sense to you?
  Constantin

• Passage of an object by a shared variable

  Hi all

  I don't know if the title is entirely appropriate, but it describes exactly what I'm trying to do.  I have an application that runs on a machine RT which I'm trying to pass an object of the application on the machine of the RT to a host.  The problem is that when I turn the object to a variant and then insert the object in the shared variable (the size of the object is about 450 b), I get no response on the coast host, indicating that the variable has updated.  Probing the error on the shared variable where I write (on the machine of the CR), it turns out I get the error code - 2147467259, an unspecified error.  Has anyone seen this error before?  Does anyone have any ideas as to why what is happening?  All other variables are responds ok.

  Thanks, Matt

  

  OK, so the solution found.  For some reason, I can't pass the object as a Variant.  However, as when I use the STM library, I can flatten the string object and then pass the data through the variable shared by using a string of SV.  This isn't an unreasonable solution, it seems I just do something very similar when I pass the data via a SV Variant.  You have any ideas as to why I can't pass it by using a Variant?  Looking forward, it is going to be any support to pass objects directly through SVs?

  Cheers, Matt

• Are published network shared variable write &amp; read Atomic actions

  Hello

  I have a very basic question about shered (published network) variable.

  I think I know the answer already, but since I couldn't find in my documentation, I thought that it is more prudent to request...

  Are reading and writing on a shared variable of stocks Atomic?

  To be more precise: on my target real time I create an array with data (each element being the configuration item or a cluster containing name, value, and type) and when the table is finished I am this store in a published network shared variable.

  On my host (Windows), I'm voting (in a loop) until the table contains at least 1 item, when this is true I'm parsing all the elements in the table.

  Is there a chance that, reading of the shared variable, the table contains a subset of the original painting on RT target (i.e. the action of reading takes place while writing is still ongoing).

  Or is the action of reading delayed until the write is completed? (i.e. both write and read actions are atomic even over the network)

  I think the latter is true but not could find no evidence in the documentation.

  Kind regards

  SoC

  Hello Rob,

  Yes, you can access the entire value, data type - you use both. For the table data type, the integer value is actually the full picture. So, Yes, you can see reading and writing as Atomic actions.

  But, on the other hand, you can lose data if the RT system rewrites the variable before the host had the time to read. To avoid this, you can enable buffering for the variable. See the following links for more information:

  http://www.NI.com/white-paper/4679/en

  http://zone.NI.com/reference/en-XX/help/371361H-01/lvconcepts/buffering_data/

  Finally, you can also activate a FIFO RT on your target RT if you need to send data through the variable in a deterministic section of the RT. See also, more information:

  http://zone.NI.com/reference/en-XX/help/370622H-01/lvrtconcepts/rt_projectvariable/

• Shared Variable (published network) communication

  Hi all

  All day I was hitting my head with variable communication shared between RT host and the host computer:

  I basically tried to pass an array of the host of the CR to the host computer. For this I used a published shared variable of network type Array U64. I used this link to help me understand usign shared variable communication

  http://www.ni.com/white-paper/4679/en ...

  I also activated RT FIFO. Now in the city that link the information given on the use of FIFO of the single element or Multi element FIFO

  "By enabling real-time FIFO, you can choose between two types of compatible FIFO slightly different variables: the only element and the buffer insurance program. A distinction between these two types of buffers, it's that the only element FIFO reports no warnings on positive or negative overflow conditions. A second distinction is the value returned by LabVIEW when several readers read an empty buffer. Several readers the only element FIFO receive the same value, and the only element FIFO returns the same value until a writer writes back to this variable. Several readers of a FIFO empty array each get the last value that they read from the buffer or the default value for the data type of the variable, if they have not read before variable. "

  I had read the content above a 100 times, but still I'm not able to get a clear picture of the difference and when to use which option. So I decided to take the text and tried to try something for me.

  I had a loop in the reception of RT who writes arrays of 3 different elements in the 'network published variable shared'. Now when I use the option of multi element with "number of berries as - 2" I am able to read tables separates one by one in the host computer (as you can read a queue in general).

  Now when I used the option of single element for the RT FIFO with 1 UN editable table option, only the last table written in the 'shared variable published network' is read in the host computer.

  This seems absolutely ridiculous as if this is the case, then what is the purpose of creating the "buffer". For testing purposes, I had put the buffer in 5 tables.

  In fact, I have only a single author (written in loop in the reception of RT) and a reader (new looping in the host computer). So I don't know even if I need option of the RT FIFO for the published network shared variable.

  I'm sorry for the long message but I've reached the limits of going around in circles waiting to type somewhere

  I know I made a mistake stupid somewher or it miss me probably a clear simple trick but don't know what it is...

  I request some clarification... In fact I posted a little while earlier today so ... bind - http://forums.ni.com/t5/LabVIEW/RT-Host-to-Host-computer-communication/td-p/2348130 )

  any help would be appreciated

  See you soon

  me

  Hello

  I think that the difference between these two types is clearer by using LabVIEW:

  "

  Activation of the FIFO in real-time

  You can activate the FIFO in real-time to a shared variable since the page FIFO in real-time of the properties of the shared Variable dialog box. Check the box Enable the FIFO in real-time in a deterministic way share data using the one element or several elements FIFO.

  Single element FIFO

  One FIFO shares the most recent value of the data. The shared variable overrides the value of data when it receives a new data value. Use this option when you need only the most recent value. Configure the size of the elements of the array or the size of the waveform for the FIFO buffer, if you select a table or a waveform data type.

  Several elements FIFO

  A FIFO multi-elements implements buffer the values shared by the shared variable. You can configure the size and elements of the buffer FIFO to match the parameters of buffering to use of the Variable page, or you can configure a custom size for the FIFO and FIFO elements.

  Note  For single item both multi-elements FIFOs, if the variable contains data table or a waveform, you must configure the size of the elements FIFO equals the size of the data to share. If the network buffer both the RT FIFO are enabled, the network buffer should be at least as big as one of the elements of FIFO. Sharing data smaller or larger that the specified length results in a memory allocation which affects determinism.

  Note  Waveforms contain variant of varying size that are not compatible with real-time FIFO. Therefore, if you enable the FIFO in real-time on a shared variable that contains the waveform data, the item variant waveform data does not transfer.

  "

  http://zone.NI.com/reference/en-XX/help/370622K-01/lvrtconcepts/rt_projectvariable/#Single_Element_F...

  ' Hope this helps

  Aurélie

• network Publish shared variable

  I'm hosting the OAS of a sbRIO engine, developing with LV10.  I share an array of Boolean values on the sbRIO and I need to be modified by (1) the sbRIO by programming the control array, and (2) a LV GUI running on PC graphically (i.e. option boxes).  I share the table and PC HMI can connect and view the States of the button as established by the sbRIO, but when I try to click on one of the radio buttons, the sbRIO seems to outweigh demand and turn the reverse button (I know demand is through, I see a very rapid change in the State of button/table on a temporary HMI connected through the sbRIO project).

  Do I need a separate shared table for applications for PC/HMI that I must then analyze via w/Combinatorial logic and find the changes then send updates until the sbRIO to write in the "master" control programmatically array?  Or is it a type of feature for arbitration to a shared Variable NP?

  THX

  Hey Atlas,

  This looks like a problem that arises from the conditions of competition, access to shared variables. You always read or write variables in a loop on each application? If the Boolean values are poised to the HMI, you must use a "send" or the "write" button that writes to the shared variable. If the HMI application is constantly reading and writing to the shared variable, you can overwhelm network variable motor and see problems like these. If you still have problems, feel free to post your screws or block diagram screenshots so that we can see what you're doing.

• How to divide a string into an array of strings in separate tables

  Greetings,

  I have an array of strings which displays strings in a text file. I read each line of the text file and put it in an element of the matrix of the chain.

  Now, I'm trying to divide each string for each part of the chain, then put in a separate table. Each element in the chain is separated by a comma. I hit a brick wall at this point and would like to help please?

  The purpose of this is so that I have 4 tables that will be ready their item values and set variables based on these values until I went through all the elements in each array.

  Attached example.

  Also my VI is attached.

  Thanks in advance for your help.

  Then just use Index Array on 2D array provided.

  

• SQL and shared Variable communication failure when you run an .exe application

  Salvation OR engineers,

  I'm faced with a problem. I have already tried almost everything under my bottom to solve, but I just couldn't get over it.

  I have a VI on my PC accessing a SQL database via the connection string and some share of variables in a server. Both shared variables and the SQL database are on the same server. There is a firewall between this server and my PC and the server is located in a DMZ environment.

  Design Labview environment, everything works fine. Even when I run the .exe on this computer file, everything works fine. But, when I created an application and install it on another computer, it just doesn't work.

  I'm using Labview 2013.

  Someone of you can help me with this bug?

  Thanks in advance!

  Hello world

  Back to share with you the solution:

  The problem was with the "SQL Native Client". Windows 7 doesn't have it as a default installation, if the application could not find the OLE DB provider for ODBC drivers. After installation, the connection has been established.

  As the server was within a demilitarized zone, I had to open some specific ports as follows:

  UDP/1434

  TCP / / 2343,49163

  59110-59115

  In fact, I have not experienced problems with the OAS. The error was generated when you try to connect to the database and sent to the rest of the code through the cluster of the error.

  Thanks for the support!

  Best regards to everyone.

  Luiz

• Shared variable data type: can I choose a picture of a typedef custom, without making the table itself a typedef?

  Hi all

  I would like to pass a table to a cluster on my network. My group is typedef'ed, but I would avoid to pollute my project with an another redundant typedef.

  Is it possible to use the option "From Custom Control... ' of the shared variable with an array without saving the table as a new .ctl file?

  Oh, I didn't know you were using shared variables. I thought that you were just considered another option with TCP/IP or UDP or something like that. In this case, you will need to create a second custom control. This control would be a table with the cluster of typedef in there. Not need to make this new control itself a typedef however. Sorry, I know you were hoping for a different answer. I doubt a single file will really be "clutter" your project well

• Can I send value cluster through the shared variable?

  Hi every1,

  I want to send a cluster through the shared variable. While creating a shared variable, there are options to choose the type of data, but there is no option to Cluster.

  But there is an option of "custom control". How to use it?

  Hi, Germain,.

  Create your control and save it as a file on your disk *.ctl. If you use the "custom control" option, and then select your control. If this does not work for your control, you can use the function 'flatten in string' to send a string.

  Mike

• How to turn RT FIFO on a shared variable for custom control

  I try to get my shared variables behave: update when I tell them of and only update once. It's the sort of 2 separate problems. Update only once should be fixed by activating RT FIFO on the shared variable. However, if you create a shared variable by using a custom control (because your data type is not available on the menu drop-down), allowing RT FIFO is not available. Why is this? Will there be an another GUARANTEED way to do this?

  Description of my goal: after having many problems with a large scale of my real-time program version, I started from scratch. My program is that the bases in order to send a signal to my goal of running on a few D/A channels, then return the data that I read A/D channels to ensure that the waveform has the same appearance. In addition, the program should be able to repeat this process without having to reboot.

  -Host is a state machine with: initialize - reset variable, check that the UI events - start target, target stop and end program, send data - to create 2 waveforms and send it to the target using the variable "data entry" (table 2D-double), data Get shared - read the entire waveform on the different channels after it ran using the shared variable "all data output" (table 2D-double) , Write to the file - (does nothing), stop - program ends.

  -Target is a loop with 2 States inside: false - target does nothing as he waits to be the host to say 'Start', True - target Gets the shared variable input data, runs on 2 D/A channels and reads the equivalent A/D channels to make sure the waveform actually ran as expected. This happens in a deterministic loop with a non-deterministic loop waiting for the command "Stop" on the host. After the written entry, the D/A signals stop and playback of signals/a. are placed in a 2D array and sent to the host via a variable shared, "all the output data".

  -J' tried to put "all the data output" in a while loop which must reiterate if he does not obtain data in the specified time-out period. I also removed the while loop but kept the specified time-out period. In both cases, data are collected twice!

  -Without specifying a time-out, the host never gets data updates "all output data" before he goes into another State.

  Summary: I need update they once when I asked to a my shared variables. I think that my program is about as simple as you can get, so I'm surprised to see why he is currently not completely reliable.

  (I have attached the vi host, target the vi and variable)

  Hi FireIce,

  To answer your questions:

  1 RT FIFOs are supported data types can be pre-allocated space. This is to keep the determinism on the RT system.

  2. reading of the variable in the loop and have the chart outside the while loop will only show the last value of the shared variable, showing actually only a single reading. Then if it works for you, it will give the same result.

  Looks like you have network buffering enabled on your shared variables. Is this true? Shared variables must always have a value, and so it will continue to contain old data to the new data is written to it. If you have buffering enabled network, new data can be added after the former, which actually look like you read the old data twice before getting the new.