Brick Wall Problem: Array of Clusters, Size of array from reference

Good Morning Forums,
I have hit a brick wall with my application and I am hoping somebody can help!
I have an array of clusters of indeterminate size (the cluster is generic, data contained not relevant.).
Inputs to the VI are: a reference to the array, and a variant containing the data.
My problem is I need to determine the array size from these two inputs and I cannot find a way to do it!
If the array contained a standard data type I can use the class name property to determine data type, and the size of the array returned from "select size" property to determine dimension size. With this information i can cast the variant into the correct data type and use this to determine the size of the array. If the data is a cluster the class name simply returns "cluster" so I cannot cast the variant and therefore am unable to determine the size.
I am not worried about casting the data (once i determine the size this bit is no issue), I just need to determine the size (and preferably number of dimensions) of the array. Can this be done?
Cheers for any help
J
John.P | Certified LabVIEW Architect | NI Alliance Member
Solved!
Go to Solution.

John.P wrote:
Good Morning Forums,
I am not worried about casting the data (once i determine the size this bit is no issue), I just need to determine the size (and preferably number of dimensions) of the array. Can this be done?
Cheers for any help
J
There seem to be a couple of potential solutions.:
#1 if the varient is created within LabVIEW you can wite size(s) to a varient attribute. This would be pretty straightforward and easy to implement- I imagine you would have thought of that so you may not have access to the code writing cluster to varient and it gets a bit trickier.
#2 cast the varient to string and return string length- this should give you a measure of total size and you would need to know the size per element of cluster (just cast one instance of cluster array to varient and then to string with size and size++) but this only returns the total size of the array since nDim arrays are actually stored sequentially.
Hope this helped
Jeff

Similar Messages

Reference to Array of Clusters with an array element

Hi,
I have an array of clusters CONTROL (calling it as "top level cluster array") with one of the cluster elements being a cluster array (please see attached).
I plan to pass "Reference" of this top level cluster to different VIs (like add element VI, insert element VI, delete element VI etc) and access (add/modify delete) the elements in this array.
In my code, how do I typecast the Array Element (cluster) to the inner cluster (as shown in the figure) ?
I am using LV RT on PXI.
Solved!
Go to Solution.

You cannot use references in the same way that you use pointers around in C. LabVIEW does not manage memory in the same way that C does. This is actually a good thing, though C programmers find it "cumbersome" or "restrictive". I have also programmed in C, and frankly I prefer LabVIEW's memory management any day of the week.
You had not initially mentioned that this was going to be done in multiple places at (potentially) the same time. Given that, my recommendation is to look into using Action Engines. They provide a means of basically providing a one-location acccess for your data. By using a single VI to access/modify your data you preclude the generation of race conditions. You may also want to join this with the concept of using variants to provide a means to quickly find your data rather than looping to find the element you're interested in. This technique has been around for a while and it has been discussed before. There are examples floating around. Will need to check to find one.
As for your question regarding using the reference method which you tried to employ in your initial approach, that's simply not going to gain you anything. You will still be creating buffers when you try to access the cluster elements. But you already have this information in the array inside the outer for loop, so you're just creating unnecessary extra programming for yourself.

Trying to clear an array of clusters with image info from memory - overflowing!

I am using a cluster with IMAQ interface name, session info, image array, and individual image and creating an array of that cluster. I try to clear the cluster by deleting the array elements, read an array of images, save them, and repeat the loop. Over time, though the arrays are tearing through all available RAM. I tried removing local variables (which I understand would save a copy of the entire array to memory every loop iteration) and had no luck - actually the code hangs now on the write function, where it thinks there is no image data. I didn't think I changed anything other than to direct wire where there had been local vars to pass information from one part of the sequence to the next. Help! (screenshots of code attached).
Attachments:
framegrab sequence 1.jpg ‏8 KB
framegrab sequence 1a.jpg ‏47 KB
framegrab sequence 2 - grab and save.jpg ‏149 KB

Hi, Nasgul,
Not sure where you have resources leak - from your screenshots its not clear.
But one is clear - you may not understand that IMAQ Images in LabVIEW passed by references. So, if you want to create array of images, then for each element IMAQ Create should be called with different name, otherwise all elements referred to the same image. For example, if IMAQ Dispose will be called for the first elementh of the array, then other 9 images will be automatically invalid.
Compare two code snippets below:
Common recipe for solving troubles with resources - reduce your application step by step by isolating parts of the code with case structures until application will be stable. Then you will found part of code which caused memory leak.
best regards,
Andrey.

Change properties of a cluster element withing an array of clusters

Hello all,
I have an array of cluster that is shaped as a line with different display elements.
A list or a tree wouldn't have made it, so I had to use a cluster and make a table.
The problem is that I want to change not only the text but also the text color.
Individually.
I found this :
http://www.ni.com/example/30904/en/
But it change the property in all the clusters in the array, not just the one I need.
Some people have the same problem :
http://forums.ni.com/t5/LabVIEW/Reference-to-Array-of-Clusters-with-an-array-element/td-p/1006427
http://forums.ni.com/t5/LabVIEW/Different-set-of-values-for-two-rings-in-an-array-of-clusters/m-p/10...
http://forums.ni.com/t5/LabVIEW/array-of-clusters-get-references-to-all-the-clusters/td-p/1079456
http://forums.ni.com/t5/LabVIEW/How-can-I-reference-the-properties-of-a-control-in-a-cluster-in/m-p/...
http://forums.ni.com/t5/LabVIEW/Writing-only-to-certain-cluster-elements-in-an-array-by/m-p/2200728
http://forums.ni.com/t5/LabVIEW/Update-Properties-Of-One-Control-In-An-Array/m-p/3015501
http://forums.ni.com/t5/LabVIEW/Array-of-clusters-and-in-the-cluster-is-a-bar-meter-how-can-I/m-p/15...
http://forums.ni.com/t5/LabVIEW/Property-node-of-a-control-inside-of-cluster-inside-an-array/m-p/946...
Obviously, while in a list/table or tree you can change the property of an individual
cell (font, color) you cannot do it within an array of cluster, by some sort of magic,
the property of a cluster element (font, color) are all linked together, hence rendering
the use of an array worthless.
A possible hack is proprosed by using control masking, setting one visible and the
other invisble, swapping their position, whatever. It's a hack you have to perform,
hence add another code to maintain.
Is that still the case or is there now a more official way to handle individual cluster
properties, not just its data ? After all that's a common real-life example that should
be handled by Labview. In my opinion.
David Koch
Solved!
Go to Solution.

altenbach wrote:
One of the elements could be a 2D picture indicator of about the same size. You can write text in any color using picture functions.
Here's what I had in mind. Seems to work just fine (I would fine-tune the font, picture border, etc. but this should get you started).
LabVIEW Champion . Do more with less code and in less time .
Attachments:
ColorText.png ‏13 KB
ColorText.vi ‏9 KB

Array of Clusters with Graph - Y Scale Change Event

Hello everyone
I have a Array of Clusters with a Graph inside each cluster. I need to trigger a event when the user type a new value on the graphs' Y scale and hit "Enter" to apply the change. Any ideas how to trigger that?
I am not considering the "mouse enter" event because I have other events linked with that already.
Thanks
Dan07
Solved!
Go to Solution.

dan07 wrote:
I think that I was not clear. Sorry. Lets thing about two arrays of clusters with graphs: Array of clusters 1 and Array of clusters 2. Both of them have their own graphs insides the clusters.
I want to do the same thing that you told me to do, but with two arrays of clusters instead of one. Changing the scale range of any graph of array of cluster 1 will trigger case A of event structure (just an example), and changing the scale range of any graph of array of clusters 2 will trigger case B of event structure (just an example again).
Then try the following. Dynamic Event Registration nodes are expandable:
a.lia-user-name-link[href="/t5/user/viewprofilepage/user-id/88938"] {color: black;} a.lia-user-name-link[href="/t5/user/viewprofilepage/user-id/88938"]:after {content: '';} .jrd-sig {height: 80px; overflow: visible;} .jrd-sig-deploy {float:left; opacity:0.2;} .jrd-sig-img {float:right; opacity:0.2;} .jrd-sig-img:hover {opacity:0.8;} .jrd-sig-deploy:hover {opacity:0.8;}

How do i send an array of clusters with variable size over TCP/IP?

Hi,
I'm trying to send an array of clusters with varible size over TCP/IP,. But I'm facing the following problems:
1) I need to accept the size of array data from the user and increase the size dynamically.
I'm doing this using the property node but how do I convey the new size to my TCP read?
2) I need to wire an input to my 'bytes to read' of the TCP read.
But the number of bytes to read changes dynamically
How do I ensure the correct number of bytes are read and reflected on the client side?
3) Is there anyway I can use global varibles over a network such that their values are updated just as if they would on one computer?
Will be a great help if someone posts a solution!
Thank you...

twilightfan wrote:
Altenbach,
... xml string. ...number of columns that I'm varying using property node s... I solved these problems by using a local variable as the type input ...o TCP read is creating a problem.... second TCP read gets truncated data because
its no longer just the first four bytes that specify the length of the data, it could be more as my array of cluster can be pretty huge.
Instead of writing long and complicated sentences that make little sense, why don't you simply show us your code?
What does any of this have to do with xml strings???? I don't see how using a local variable as type input changes anything. The user cannot interact with "property nodes", just with controls. Please clarify. Once the array of clusters is flattened to a string you only have one size that describes the size of the data, no matter how huge it is (as long as it is within the limits of I32). Similarly, you read the string of that same defined length and form the array of clusters from it. How big are the strings? What is your definition of "huge"?
Here's is my earlier code, but now dealing with an array of clusters. Not much of a change. Since you have columns, you want 2D. Add as many diensions you want, but make sure that the control, diagram constant, and indicator all match.
The snipped shows for a 1D array, while the attached VI shows the same for a 2D array. Same difference.
Message Edited by altenbach on 01-31-2010 01:13 AM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
FlattenArrayOfClusters.vi ‏12 KB
ioclusters3MOD.png ‏25 KB

Problem updating an array of clusters that contain guages

Hello,
I'm having problems when I write to an array of clusters that contain guages.
I wrote an example program to illustrate the problem.
I create an array of cluster of [numeric, numeric].
I populate 4 elements of the array with data.
If I pull out each element with an Index Array function and write the data to 4 indicator clusters independently, I have no problems.
If I wire the 4 element array to an array of clusters, the needles on the guages won't redraw properly.
However, simply moving the mouse over the array element causes the display to redraw just that element.
I've played around with Synchronous Display and Defer Panel Updates but they don't seem to affect this behaviour.
Any thoughts?
A picture of the problem and the VI are attached.
Solved!
Go to Solution.
Attachments:
guage.JPG ‏56 KB
DisplayUpdateTest.vi ‏56 KB

johnsold wrote:
Interestingly one element of the array (but not always the same element) seems to update properly while the others do not. Note Index 1 in the image. I saw it do this with Index 2 earlier. This also shows in the OPs image.
Lynn
I too witnessed this same behavior, but it was intermittent.
Reese, (former CLAD, future CLD)
Some people call me the Space Cowboy!
Some call me the gangster of love.
Some people call me MoReese!
...I'm right here baby, right here, right here, right here at home

Convert array of clusters to cluster of arrays without for loop

Hi!
Here's a problem: I've got an array of clusters (array of messages). Each cluster consists of elements of different data types: double (time), cluster (parameters), char (station id), byte (message code). I know one cluster size and the array size. I need to draw a time graph. How can I convert the array of clusters to a cluster of arrays (array of time values, array of parameters clusters, arrays of chars and bytes).
I post this question because in my real array of clusters each cluster consists of 162 elements and some of them are clusters themselves, so I realy dont want to wire "for" loops as was advised in other topics.
Hope to get fresh ideas. Memory management? Type Cast? FlatternStrings and variants? Anything!
Thank you.

Idea wrote:
Hi, everybody! Glad you read the post!
There is the cluster in the attachment. The application I make is a TCP client. The cluster is a message. Actually I get a string, find edges ("DIAG" - begin, "GAID" - end) and then I use "unflattern to string" for making the cluster. I cann't make another structure of the message - I didn't make the server. My client has a buffer of recieved messages. I need to plot graphs of different cluster elements for all messages in my buffer (for example the Time 1 element). If I use the for loop it would be too slow. The idea was to convert all buffer to a 2D array of U8 and then use type cast to get the cluster of arrays. Then it would be easy to take ane cluster element and send it to graph.
I didn't sucseed yet.
Idea.
What is your question about?
A) convert the string you get from I don't know where to the giant cluster, the red part in your message, or
B) making a graph out of some element from that giant cluster, who now is in an array, the blue part in your message.
The code you showed us looks a solution for question A but no loop is needed for this. So why bother about a loop that would be too slow here?
Also your code start from an array of U8, so where's the string?
If you could provide a string that needs conversion, we could try another way ... ...
Question B can easily be solved with a for loop and "unbundle by name". Don't know where you get the idea that a loop would be too slow
Open G library has a lot of VI's to retrieve specific elements from clusters, maybe one of those could help solve the problem.

Using Event Structures with Array of Clusters

Using LabVIEW 8.5
Hi all,
I'm trying to convert an existing application to one that can be used
through a touch screen. I updated the UI and added an event structure
to listen for mouse ups on controls that require a HMI keyboard or
numpad to show up. Although I've been programming for a while, I'm new
to LabVIEW and am struggling with a problem:
Is there any way to have an event case listen to an event within
arrays? I've seen a few examples on the forums, but they all start with
breaking up the arrays into individual variables. Using the variables,
they build arrays. This seems pretty tedious, and I'm pretty sure I
can't apply it to one of my arrays. Essentially, I just want to know
which cluster in which array the user has clicked on, so I can open the
HMI keyboard or numpad and send the text to that cluster. In my watered down app (Array of Clusters.vi), I've put 3 arrays of clusters and a few stand-alone controls to give you guys an idea of what I'm taking about.
BTW, I'm using the HMI Keyboard and Numpad built by the Beta Community (http://decibel.ni.com/content/docs/DOC-1062) and modified it to add a "Clear" button to the keyboard and numpad. Please let me know if I implemented this in the best way.
Thanks for the help,
Kunal
Message Edited by bhatiak on 08-04-2008 03:55 PM
Attachments:
Array of Clusters4.llb ‏274 KB

My old tic tac toe example shows how to determine which square of a 2D array has been clicked.
http://forums.ni.com/ni/board/message?board.id=170&view=by_date_ascending&message.id=247044#M247044
You probably can adapt some of it for the arrays on the right. If the array can be scrolled, you also need to account for the "indexvals" offset.
The Layers controls is easiest, because you only show one element. Just read the "index vals" property to get the array element and parse the coordinates to get the cluster element.
btw: the small while loop on the right serves no purpose at all and acts just as a CPU burner. You can delete it without any change in functionality. Is there anything else to it?
LabVIEW Champion . Do more with less code and in less time .

How can i segregate an array of clusters with channels id in the cluster

Hi All
i am using a keithley 2010 DMM for power measurements,
i am using the 2010 scan read VI which gives the reading output as an array of clusters, these clusters contain the measurement,units,channel.
i have 6 channels for measuring voltage across and i want to make 5 readings per second on each channel which makes upto 30 readings per second.
i want to segregate these clusters from the array according to the channel id and take the results,
please tell me if we have function for this or you have any possible solution for the same.
i would be very happy to hear from you and get this solved
please help
Thanks in advance
Sandeep K Shyam

yeah this looks great...thanks for your response,
i have modified accordingly and attaching the VI, can you please look into this once
also one more problem i have with this VI is whenever i am trying to run the VI, the sub VI (Scan config.vi) gets popped up and waits for user response (next) cntrl+right arrow, how can i get rid of this and run the VI in continues mode?
i am attaching my VI along with the kei2010 lib,
please check this
Thanks again
sandeep K shyam
Attachments:
sandeep-FinalKeithley20101.vi ‏822 KB
kei2010.llb ‏901 KB

Variable size 2D arrays

Good afternoon everyone.
I need to allocate array of buffers (arrays). Each buffer would be different size. When implementing this in C/C++ it would look like an array of pointers where each pointer would point to a specific array. Each array could be NULL terminated to know exactly where it ends.
How can I implement this in LabVIEW? Two dimentional arrays are an option, but would waste a lot of memory since the second dimmention would have to be the dimmention of the largest buffer.
Please help.
Thank you in advance,
BorisMoto

Well, you can use an array of clusters, where each cluster holds a 1D array. I think this would take less memory but it would definitly be more complex becuase you're adding the cluster operations. To do this, create a 1D array, drag it into a cluster and drag that cluster into another array. It's possible that this isn't any better. You can measure the performance difference by using VI profiling (Tools>>Advanced) and by using timing (the time the VI stopped minus the time it started).
Try to take over the world!

Array of Clusters Counters / Shift registers

Hello All,
In my Array of Clusters, I'm having trouble controlling my MISS PACKET indicator. Each time a packet is missed , the MISS PACKET indicator increments by 1. My problems is, that the same number of miss packets is showing up in the MISS PACKET indicator in each array index if a packet is missed. Ex. So if index[0] has missed 30 packets, whenever index[1] misses a packet it will display 31 and not 1. I'm using a shift register to keep a count of the number of missed packets. I believe the shift register is the issue because the previous value is store whenever a packet is missed.
Any help would be appreciate !
Thanks
Attachments:
Final-Demo - 3.vi ‏52 KB

The first time i tried using a shift register I had the initalization done outside of the while loop and still got the same results
Attachments:
Final-Demo - 3.vi ‏47 KB

Array of clusters TAB next element

I have an array of clusters and I want with the TAB key, when I am at the last element of the cluster i, move to the first element of the cluster i+1.
Jean-Marc
Jean-Marc
LV2009 and LV2013
Free PDF Report with iTextSharp
Attachments:
Array of clusters.jpg ‏132 KB

Thanks for they answers.
My problem is the triple TAB (TAB -TAB -TAB) to change the array line i to i+1.
Click on an element in the array and move with the TAB key. When you are at the element "VOC":
- the first TAB (event "<VOC>:Key Down?" ) generate CTRL +UP (return to tabbing among front panel controls -return to CLUSTER at line i);
- the second TAB (event "<Cluster>:Key Down?" - sequence through the array- move to the array line i to line i+1)
- the third TAB (event "<Cluster>:Key Down?" )generate CTRL + DOWN ( move the key focus inside the array or cluster -move inside the cluster at the line 1+1);
I try to reduce the number of TAB.
Jean-Marc
"Complete the following steps to
use the <Tab> key to move through elements within a single array
or cluster when you run a VI.
Display the front panel. While the VI is running, press the <Tab> key until the array or cluster is highlighted.
Press the <Ctrl> key and the down arrow key to move the key focus inside the array or cluster. (Mac OS) Press the <Command> key. (Linux) Press the <Alt> key.
Press the <Tab> key to sequence through the array or cluster elements and the array indexes.
To return to tabbing among front panel controls, press the <Ctrl> key and the up arrow key. (Mac OS) Press the <Command> key. (Linux) Press the <Alt> key."
Jean-Marc
LV2009 and LV2013
Free PDF Report with iTextSharp
Attachments:
Tab Array Clusters LV8_0.vi ‏94 KB

Call library function node with array of clusters using array data pointer

Hello all.
I am writing a LabVIEW wrapper for an existing DLL function.
The function has, as one of its parameters, an array of structs. The struct is very simple, containing two integers. I am using the call library function node to access it.
In Labview I created an array of clusters, where the cluster has two 32-bit integers as its members. So far, so good.
Now I have to pass this in to the Call Library Function Node. Here I am running into trouble.
I have used The topic in LAVA and The topic in the knowledge base as my primary sources of information, though I have read a bunch of forum topics on the subject too.
I do understand that I could write a new function which takes as a parameter a struct with the size as the first member and an array as the second, and I might just do this and have it call the regular function, but I was hoping to do it more simply.
According to the C file which LabVIEW generates for me from the CLFN when I choose "Adapt to Type" and "Array Data Pointer", the prototype it is expecting is:
int32_t myFunc(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, void data[], int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex);
And the prototype of the function in my DLL is
int borland_dll myFunc(DWORD handle, usint channel,
int FIFOnumber, struct mStruct *data, int numWords, int *actualLoaded, int *actualStartIndex);
This looks like a match to me, but it doesn't work (I get garbage in data). From the topic in LAVA referenced above, I understood that it would work. It does not.
If I cast data to the pointer-to-pointer I get when I generate c code by wiring my struct to a CIN and generating, then I seem to get what I expect. But this seems to work when I choose "pointers to handles" too, and I would expect array data pointer to give a different result.
Is there any way to get this to work directly, or will I have to create a wrapper? (I am currently using LabVIEW 2011, but we have customers using 2009 and 2012, if not other versions as well).
Thank you.
Batya
Solved!
Go to Solution.

OK, here is more detailed information.
I have attached the VI.
This is the code from the "C" file created by right-clicking the CLN and creating a "C" file.
When the parameter in the CLN is set to "array data pointer":
/* Call Library source file */
#include "extcode.h"
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, void data[], int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex);
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, void data[], int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex)
/* Insert code here */
When the parameter is "pointers to handles":
/* Call Library source file */
#include "extcode.h"
/* lv_prolog.h and lv_epilog.h set up the correct alignment for LabVIEW data. */
#include "lv_prolog.h"
/* Typedefs */
typedef struct {
int32_t control;
int32_t data;
} TD2;
typedef struct {
int32_t dimSize;
TD2 data[1];
} TD1;
typedef TD1 **TD1Hdl;
#include "lv_epilog.h"
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex);
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex)
/* Insert code here */
When the parameter is set to "handles by value":
/* Call Library source file */
#include "extcode.h"
/* lv_prolog.h and lv_epilog.h set up the correct alignment for LabVIEW data. */
#include "lv_prolog.h"
/* Typedefs */
typedef struct {
int32_t control;
int32_t data;
} TD2;
typedef struct {
int32_t dimSize;
TD2 data[1];
} TD1;
typedef TD1 **TD1Hdl;
#include "lv_epilog.h"
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex);
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex)
/* Insert code here */
As to the DLL function, it is a bit more complicated than I explained above, in the current case. My VI calls the function by this name in one DLL, and that DLL loads a DLL and calls a function (with the same name) in the second DLL, which does the work. (Thanks Rolfk, for helping me with that one some time back!)
Here is the code in the first ("dispatcher") DLL:
int borland_dll Load_Transmit_FIFO_RTx(DWORD handle, usint channel, int FIFOnumber, struct FIFO_DATA_CONTROL *data, int numWords, int *actualLoaded, int *actualStartIndex)
t_DispatchTable *pDispatchTable = (t_DispatchTable *) handle;
int retStat = 0;
retStat = mCheckDispatchTable(pDispatchTable);
if (retStat < 0)
return retStat;
if (pDispatchTable->pLoad_Transmit_FIFO_RTx == NULL)
return edispatchercantfindfunction;
return pDispatchTable->pLoad_Transmit_FIFO_RTx(pDispatchTable->handlertx, channel, FIFOnumber, data, numWords, actualLoaded, actualStartIndex);
borland_dll is just "__declspec(dllexport)"
The current code in the DLL that does the work is:
// TEMP
typedef struct {
int control;
int data;
} TD2;
typedef struct {
int dimSize;
TD2 data[1];
} TD1;
typedef TD1 **TD1Hdl;
// END TEMP
int borland_dll Load_Transmit_FIFO_RTx(int handlertx, usint channel, int FIFOnumber, struct FIFO_DATA_CONTROL *data, int numWords, int *actualLoaded, int *actualStartIndex){
struct TRANSMIT_FIFO *ptxFIFO; //pointer to transmit FIFO structure
usint *pFIFOlist; //pointer to array of FIFO pointers to FIFO structures
int FIFOentry, numLoaded;
usint *lclData;
usint nextEntryToTransmit;
// TEMP
FILE *pFile;
int i;
TD1** ppTD = (TD1**) data;
TD1 *pTD = *ppTD;
pFile = fopen("LoadFIFOLog.txt", "w");
fprintf(pFile, "Starting Load FIFO with %d data words, data pointer 0x%x, with the following data&colon; \n", numWords, data);
for (i = 0; i < numWords; i++) {
fprintf(pFile, "%d: control--0x%x, data--0x%x \n", i, data[i].control, data[i].data);
fflush(pFile);
fprintf(pFile, "OK, using CIN generated structures: dimSize %d, with the following data&colon; \n", pTD->dimSize);
for (i = 0; i < numWords; i++) {
fprintf(pFile, "%d: control--0x%x, data--0x%x \n", i, pTD->data[i].control, pTD->data[i].data);
fflush(pFile);
// END TEMP
if ((handlertx) <0 || (handlertx >= NUMCARDS)) return ebadhandle;
if (cardrtx[handlertx].allocated != 1) return ebadhandle;
pFIFOlist = (usint *) (cardrtx[handlertx].segaddr + cardrtx[handlertx].glob->dpchn[channel].tr_stk_ptr);
pFIFOlist += FIFOnumber;
ptxFIFO = (struct TRANSMIT_FIFO *)(cardrtx[handlertx].segaddr + *pFIFOlist);
//use local copy of ptxFIFO->nextEntryToTransmit to simplify algorithm
nextEntryToTransmit = ptxFIFO->nextEntryToTransmit;
//on entering this routine nextEntryToLoad is set to the entry following the last entry loaded
//this is what we need to load now unless it's at the end of the FIFO in which case we need to wrap around
if ( ptxFIFO->nextEntryToLoad >= ptxFIFO->numEntries)
*actualStartIndex = 0;
else
*actualStartIndex = ptxFIFO->nextEntryToLoad;
//if nextEntryToLoad points to the last entry in the FIFO and nextEntryToTransmit points to the first, the FIFO is full
//also if nextEntryToLoad == nextEntryToTransmit the FIFO is full and we exit without loading anything
if (( (( ptxFIFO->nextEntryToLoad >= ptxFIFO->numEntries) && (nextEntryToTransmit == 0)) ||
( ptxFIFO->nextEntryToLoad == nextEntryToTransmit)) && (ptxFIFO->nextEntryToLoad != INITIAL_ENTRY)){
*actualLoaded = 0; //FIFO is full already, we can't add anything
return 0; //this is not a failure, we just have nothing to do, this is indicated in actualLoaded
numLoaded = 0;
lclData = (usint *)data; //must use 16 bit writes to the module
//conditions are dealt with inside the for loop rather than in the for statement itself
for (FIFOentry = *actualStartIndex; ; FIFOentry++) {
//if we reached the end of the FIFO
//if the module is about to transmit the first element of the FIFO, the FIFO is full and we're done
//OR if the module is about to transmit the element we're about to fill in, we're done - the
//exception is if this is the first element we're filling in which means the FIFO is empty
if ((( FIFOentry >= ptxFIFO->numEntries) && (nextEntryToTransmit == 0)) ||
((FIFOentry == nextEntryToTransmit) && (FIFOentry != *actualStartIndex) )){
*actualLoaded = numLoaded;
//set nextEntryToLoad to the end of the FIFO, we'll set it to the beginning next time
//this allows us to distinguish between full and empty: nextEntryToLoad == nextEntryToTransmit means empty
ptxFIFO->nextEntryToLoad = FIFOentry;
return 0;
//we reached the end but can continue loading from the top of the FIFO
if ( FIFOentry >= ptxFIFO->numEntries)
FIFOentry = 0;
//load the control word
ptxFIFO->FifoData[FIFOentry * 3] = *lclData++;
//skip the high of the control word, the module only has a 16 bit field for control
lclData++;
//now put in the data
ptxFIFO->FifoData[(FIFOentry * 3) + 2] = *lclData++;
ptxFIFO->FifoData[(FIFOentry * 3) + 1] = *lclData++;
numLoaded++;
//we're done because we loaded everything the user asked for
if (numLoaded >= numWords) {
*actualLoaded = numLoaded;
ptxFIFO->nextEntryToLoad = FIFOentry+1;
return 0;
//if we reached here, we're done because the FIFO is full
*actualLoaded = numLoaded;
ptxFIFO->nextEntryToLoad = FIFOentry;
fclose (pFile);
return 0;
As you can see, I added a temporary diagnostic with the structures that were created in the "Handles by value" case, and print out the data. I see what is expected, whichever of the options I pick in the CLN!
I understood (from the information in the two links I mentioned in my original post, and from the name of the option itself) that "array data pointer" should pass the array of data itself, without the dimSize field. But that does not seem to be what is happening.
Batya
Attachments:
ExcM4k Load Transmit FIFO.vi ‏15 KB

Initializing data in an Array of Clusters

First, thanks in advance for reading this request.
Second, the situation:
I am using an array of clusters for process control.
The cluster contains a boolean, a typedef ring control, and two numeric controls (doubles).
Depending upon the user-requested operation I need anywhere from four to 20 cluster elements in the array.
Raw data for the two numeric controls are contained as elements in three different input clusters.
Each numeric control in each array cluster can use from none to four elements from the input clusters with various additions and subtractions (no mults or divs).
The boolean and ring can be set as constants for each element based on the user request.
Third, the request:
Is there a simple way to initialize the values in the cluster (and hence the array) without having to run wires everywhere?
I have been writing embedded code and PC applications for many years and am only recently tackling LabView.
In C, I would create a structure of the four elements and then create and array of structures.
The initialization would require a few lines of code.
I have tried using formula nodes (perhaps incorrectly). All they do is remove the Numeric blocks (like + and -), but they don't create the cluster.
I am sure that there is an easier way of accomplishing what I need to do, I am just too inexperienced to know what it is.
Any help or suggestions is welcome.
Thanks in advance.

Create a cluster with the desired default values as diagram constant, wire it to "initialize array" and wire the desired array size.
The output will be the desired construct that you could write to e.g. a local variable of the target.
I hope I understood you correctly. If not, attach a small VI containing your array.
LabVIEW Champion . Do more with less code and in less time .

Brick Wall Problem: Array of Clusters, Size of array from reference

Similar Messages

Maybe you are looking for