How to use property nodes?

Similar Questions

• How to use the node to call a library function to convert C++ source codes

  Hi all

  There are two dll name 'QMSL_WLAN_Transport.dll' and 'QCAMSL_MSVC10R.dll' and some codes c ++ to connect to the DUT. The two DLLs work together for communicaite with the DUT.

  I am confused as how to use the node to call a library function to load the 'QCAMSL_MSVC10R.dll' function as

  g_hResourceContext = QLIB_ConnectServer_UserDefinedTransport((HANDLE) USER_HANDLE,
  UserDefinedSend,
  UserDefinedReceive,
  UserDefinedFlushTxRx,
  true,
  true);
  

  It seems that 'UserDefinedReceive, UserDefinedSend, UserDefinedFlushTxRx' Processaddress?  And "UserDefinedReceive, UserDefinedSend, UserDefinedFlushTxRx"'s functions in 'QMSL_WLAN_Transport.dll '.

  UserDefinedReceive = (_UserDefinedReceive)GetProcAddress(hUDT,"UserDefinedReceive");
  UserDefinedSend = (_UserDefinedSend)GetProcAddress(hUDT,"UserDefinedSend");
  UserDefinedFlushTxRx = (_UserDefinedFlushTxRx)GetProcAddress(hUDT,"UserDefinedFlushTxRx");
  

  Attached DLLs and C++ code snippets.

  Need help.

  Thank you.

  These parameters are reminders - pointers to functions that are called by the DLL - and there is no way to duplicate this purely in LabVIEW. Search this forum for the word "recall" and you will find similar questions (for other DLLs). You will need to write your own DLL (in C, C++, etc.) that implements these functions and provides a way to transfer data to LabVIEW.

• How to use the node function call library for a function in the dll with the data SUB type

  Hi all

  I would ask for your kind help

  I am facing a problem with the call library node.

  I have a C++ (stdcall) function, which has Sub as data type

  XXXX error code (hwnd, lid, getValue, * Sub data1, * Sub data2)

  data1 and data2 types are constantly changing based on the value of 'getValue '.

  Mainly I can use the call library node several times and adapt each node according to the types of data data1, data2 and extract the values and use in the code. Here is no question. Real question is:

  My question:

  How can I use a node of library time call and make a case according to the 'getvalue', who will control the data1, data2 data type. Here I really seeking solutions.

  My tests:

  I used varaints as entry to the libray call node of the data1, data2 and selected parameters in the call libraby node as "Adapt to type. Here labview just crashed.

  I appreciate your suggestions to feedbackand.

  Thank you

  Karine

  You must allocate enough space for data1 and data2, and then pass a pointer to this space. An easy way to do this is the function to initialize table. Set the U8 type and size for the number of bytes required. Pass this array to the function as a pointer of table data.

  After the function call returns, you need to extract the data in the table. You can do it manually, but a simple approach is to use the array of bytes to a string. Then, in a housing structure, use Unflatten chain to convert the string to the correct data type. This method also converts the "endianness" which will be probably necessary; Be sure to only set all entries for unflatten correctly.

• distinguish between the indicator and controls using property nodes

  How can I distinguish between controls and indicators property nodes?

  I find that the controls and lights on the Panel before all come from the same class... a digital control and a digital indicator share the same properties... I am trying to find a way to distinguish between the two.  I would like to be able to analyse a reference VI pull only the references to the "controls" or "indicators" on the front panel... but when I try this, I shoot all...

  Although I found this case a knot of property ' control value: get all ' referral of VI, I can choose between only indicator or only the values of the controls... it's close to what I want, but instead, I like to shoot only the references to the Group of the "indicators" or only the references to the groups 'controls '.

  does anyone know if there is a simple way to do this?

  Thank you very much!

  

  Suprisigly to search for flags search controls

• Programmatic property node

  I'm running into a bit of a problem with Labview which until now we were able to kind of work around, but it is more a problem, we are working on our application.  I'm using Labview as a user interface to control and retrieve the information of a Zigbee wireless network.  Part of our application requires using a large number of Boolean flags on the front panel, each representing a wireless device.  From now on, we from our application with a number of hidden indicators and making them visible one by one like devices introduce yourself on our network; This is a workaround for the fact that he doesn't seem to be a way to programmatically create indicators.  If I want to change the position of a subset of these indicators properties using property nodes, is it possible to programmatically reference an indicator?  For example, that our indicators are named Tag1, Tag2, Tag3, etc..  It would be easier to have a loop that writes the positions to a generic property node that can be referenced to specific indicators, perhaps the entry is a string for the indicator label that can easily be incremented according to the current iteration of the loop for.  Is this possible or is at - it another way to do this?  Thank you.

  Dan

  DanRW wrote:

  .. .it does not seem to be a way to programmatically create indicators...

  This is true; We cannot add new items since she would need to recompile the code running. Your method of masking/display of objects is quite valid, however, and I've seen it used in many GUI.

  ' This code snippet is similar to Jeff, and yet allows you to enter a name of a control (IE LED indicators are considered as controls in the VI server references) and move it by pressing the change Position of "boolean lock.

  

• How to change the value of the array element by using the property node

  Hello all :)

  IM using a table in the drop-down list box. the size of the array is not fixed.

  I want property strings [] from the drop-down list box to enter text in selection, but since I placed it inside the table im unable to use this property.

  I used 'arrayelem' reference property and property node connected to it but got no strings [] in the selection.

  so is it possible that I can use property strings]

  
  

• How to change the value of string clustered, to implement using the node value of property instead of writing directly on the flow of data or using the variable

  new to labview :-) and I have a problem when I want to change the value of a string in bunches, and I want to implement this using the node value of property instead of writing directly to the stream or by using the variable, enclosed is the picture.   No matter, I have change in cluster (control) or value of Popery out (indicator) cluster, the value (sensor 7) dataflow keeps unchanged even I gave the new value by value of property node. Thank you to give me some advice about this.

  

  Hi GerdW

  Thanks a lot for your answer. The reason I'm stubbornly tring to break the flow of DATA is: we have a test system that have about 100 screws, they have a few connected flow, some of them will be unbundling a cluster dataflow chain to check the value in order to make the different cases.  Now I want to insert user event by changing the control and influential cases during run time.

  As I initially uses a global variable (to control cases) instead of unbundle string data flow, it works well.  But then, I found there are a lot of screws that are using the string unbundle.  One of the 'lazy' means, I tried is to change the value via the property node (because that way, I did not need to find all the places where using the unbundle string and replace them with the global variable), then I noticed a problem with "dataflow", the value in the stream of cluster in fact will not be changed by changing the value of the property node.

  I did a test with VI simple (like the picture in last post), and after reading your advice, I tell myself that I need to understand the concept of "DATAFLOW" in labview, it seems that my "lazy" way can not work in this scenario.

  I have attached the criterion VI here, have you furthur suggestions on what I can do in this case?

  Mant thanks!

  Minyi

• Bytes to Port property node. When to use and when not?

  Hi all

  Ive frequently used bytes to port property node performing bed series and have not experienced any problems.  I've heard mixed on this subject reviews and I would like to know when to use and when not to use it.

  Thanks for any input.

  I will start by when it should not be used.

  When there are (as readable) ASCII data to come through and it is separated by a termination character.  Select the stop character and read more bytes than you ever expect a given message.

  When there are binary data, but a protocol where you know clearly how the message package is put in place.  In this case, you want to disable the stop character because any octet can be given legitimate and be interpreted as the stop character.  With these protocols, if you know the message is always X bytes, read X bytes.  If the message is of variable length, but the Protocol is set to tell you low for a long time the message is, and then make partial readings.  So if each message starts with 2 bytes that says follow X bytes.  Then read 2 bytes, which converted to a number, then read this number of bytes.

  When to use:

  The only time will really use bytes to the port is if you use a terminal of the installation type.  Just enter and display on-screen what never happens happened at the port since the last time it was read.  When you don't care where are message breaks.

  If you use bytes to the port and care message breaks, then you're obligated to all your new message concatenated to a string, you store in a shift register and each reading analysis through data to determine if you have a complete message and valid.  If you do not, do nothing and go back and read more.  In fact, you will need to run through the chain of data several times in a row before coming back to reread in the case where the message ever resulted in a single reading packets.

  The vast majority of applications falls into one of the above situations.  The last situation is not as common, and if you use bytes to the port with a system of e-mail that has defined a defined protocol or packages, you do a job more in programming to maintain a software buffer of data as well as the hardware buffer to the serial port.

• used in a Subvi LabVIEW property node

  I have a group of Boolean control front, I want to minipulate the visibility and color (4) in a Subvi.  I created a Boolean refnum cluster and spent by them in VI.  In VI, I created a group of CTLRefnum that I used as entrance pole.  In the Subvi, I am able to control the visibility through the time property node, but the Color property node (4) does not appear as a selection in the Sub - VI.  Any ideas on how I could control the colors in a Subvi.

  Hello HEJ@WR,

  Looks like you may have thrown your refnums Boolean to more generic control refnums - as the Color property is specific to Boolean values, you will need to ensure that you are now the reference type.  Visibility is a property more generic that applies to all types of controls. Refer to this article for more information on casting refnums:

  LabVIEW Help: For more specific class function

  http://zone.NI.com/reference/en-XX/help/371361H-01/Glang/to_more_specific_class/

  LabVIEWWiki also has a very good discussion of types refnum and properties specific to the class here:

  LabVIEWWiki: Control references

  http://labviewwiki.org/Control_References

  Also - if you set the example code showing what you're trying to do is much easier for other users of the forum help!

  Kind regards

• How to set the property node maximum xscale for several scale XY Chart

  Hello

  I use a graph XY with three X axis and three scales of axis Y to draw the three sets of data. This works well.

  What I do now is to set the Xscale.Maximum property node for one of the x-axis (the other two autoscale). If I click right in the (Create Blockdiagram; Node property; X scale; Maximum) I can not choose what x-axis I want to put the Maximum for.

  So my question: how to select a specific axis allows you to set the XScale.Maximum property node when having several axes?

  Thank you for your help, any suggestions are appreciated!

  Hello

  After some more research and experimentation, I found that using the scale property X Active I can determine/set for which the XScale.Maximum Xscale is used.

  This solved my problem.

  I hope someone else can save themselves a few hours with this thread!

  Thank you

• How can I resize the window of my table using the node of furniture? Thank you

  Hello

  I want to first the size of the window of my table using its property node but I can't put it to "write".

  If anyone knows if this is possible?

  Thank you

  User

  Hello

  Some properties are 'read only' and there is not that you can do about it.

  However, to set the size of your chart, you can use the "conspiracy area.size" (I don't know how it was translated into french) can be found here:

  

  Hope this helps

• Is it allowed to use property value nodes?

  To remove the problems of spaghetti, I need to delete rows.

  Previously, I used local variables, but the values written to local variables could not be found in time.

  So I started using nodes of property value instead.

  Are safe as substitutes to the lines?

  CITA wrote:

  To remove the problems of spaghetti, I need to delete rows.

  LabVIEW includes wires, no lines. What do you mean by "need". WO is you force?

  The program work correctly?

  So you have beautiful, clean and narrow (son) 1 d elements and that you want to replace by larger elements 2D (local variables, the property value nodes) across face significantly more chart area?

  Because you now also remove the dependencies of hard data, you probably need to add sequence structures, to keep racing in failure conditions. This will clutter the diagram even more! Why do you think that is the solution to your problems?

  Basically, you replace spaghetti with something worse still, for example, the content of the dumpsters behind an Italian restaurant after a night occupied.

  CITA wrote:

  Previously, I used local variables, but the values written to local variables could not be found in time.

  What is your definition of "appropriate"? The use of knots of property and local variables does NOT accelerate your code. In fact it will make it slower. As mentioned, race conditions can indeed retrieve outdated values before they have been updated to the current values elsewhere, so "timely" could easily turn into "too early."

  If you have performance problems, you don't want to chop the code and become even more fragmented.

  CITA wrote:

  So I started using nodes of property value instead.

  They have exactly the same problem as local variable, but are more demanding on resources. What was your thought process, perhaps?

  CITA wrote:

  Are safe as substitutes to the lines?

  Yet once, LabVIEW didn't 'lines', except in the range of decoration. Local variables and property nodes make code significantly less safe, because they make them much more difficult to find and avoid race conditions. They also make debugging almost impossible.

  You can start from scratch with a design template set and a code well structured and hierarchical.

  If you still think there are too many wires, consider using clusters and berries. Dozens of scalar son can replace a single cluster thread. A multidimensional array can carry millions of data points in a single thread. You get the point!

  It is difficult to give advice more targeted without actually seeing some of your code. Feel free to join so we can give more specific comments. There are many examples here in the forum where we were able to copy the HTML code to 10% of the original size while making it faster and cleaner at the same time still to add additional features. All this without the need for local variables and property nodes.

• How to create a specific property node w / script of VI

  I am writing a VI script to work with multi column list boxes.  I need to create a property node that gets a reference to the REF field.  I see that I can create a property via the method invoke Create.Property node node node, but how to get the REF field specifically I have so far can't understand.  Can anyone help?

  To be clear, I write code that looks like this:

  

  .. .and when I run the script, I want to produce this:

  

  At the time current it produced as planned MCL, via the node of the new VI object... but I don't know how to get the Ref created automatcially.  I thought that it would be in the table PropItems, but so far without success.

  Thank you

  "PropItems []" exit will be a table in a single element.  This element of the index and the reference to a node to invoke the wire.  Select the mode "SetProperty".

• Use the node property to get the value of control

  Hi all

  I know that you should keep the use of local variables to a minimum in order to avoid race conditions. Is this the same problem if you using the eg property node. a digital control?

  The reason why I want to do is to keep the son of the intersection when I need to use a control on one side of the diagram across the diagram...

  Basically to make the scheme simple and enjoyable to watch.

  I hope that makes sense!

  Good day!

  Kind regards

  Tommy

  Tombech84 wrote:

  [...] Is this the same problem if you using the eg property node. a digital control? [...]

  Exactly. Perhaps, he creates the race conditions and should not be used. Using wires to connect the terminals is the approach only "Save".

  In addition, performance decreases in the following order:

  -Terminal (+)

  -variable (0)

  -property to value node set (-)

  Norbert

• How can I control the elements in the graphic palette (profile line) via the property node?

  Hello everyone,

  Is it possible to control the elements (graphic palette in the profile of the line) via the property node?

  Greetings zapfle

  In general, you must balance only Min/max property, then you can "zoom and Pan" by program:

  

  Andrey.