Michael Aivaliotis

Hi

Well i am a newbie at LABVIEW and i am using LABVIEW v5 as well as 7

I am a dummy on building LV applications. Can any one please guide me

for the starting steps to build an application.

Further more i need the link to download the free APPLICATOIN BUILDER software for LV.

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First things first...

Application builder is NOT free. You must purchase it from National Instruments for the version of LV that you are using. After you do this, read the documentation that comes with it and if you have problems or questions come back here so we can help you out.

Do you have any specific Application Builder questions that you want answered before you purchase it?

I added 7.1.1 to the list of LV versions you can select in your personal profile configuration.

... It says in the manual that hitting the stop button on top (next to the run button) doesn't really stop the program.  It seems like it doesn't stop any loops that are active.  This is conjecture on my part though, I've only been using it for about a month.  Some of the crashing might also be due to me running Windows 98....

... I've been enclosing everything in While Loops, and placing a stop button within that loop.  Is this the safest way to run things continuously?

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K, pressing the stop button on the toolbar next to the RUN button is a no, no . This is used only as a last resort to break your program if you've made a programming error and you are stuck in an infinite loop or something. You should always create a programmatic stop to your program. The method you use by enclosing code in a while loop is the best... you're on the right track. :thumbup:

AFIK the super duper secret INI file settings only cause that the vi-scripting properties/methods are visibile in the properties/methods right-click-menu ...

there is no difference if you copy the nodes from an other vi or create them by right-clicking ...

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Yes, there is no difference, however to copy the nodes from an other vi assumes that you already have another vi to copy from.

We need to get some of these things into a bunch of subVIs, put them into a pallete with the Merge option on the menu and make up our own LAVA/OpenG Scripting pallete/toolset.

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This is a good idea. I know there are many out there that have done this already. Perhaps we can release an OpenG package with this stuff.

I simply want to change the assigned Device for a already specified channel - You apparently can treat DAQ tasks/channels as strings and use string parsing to replace/update the channel content

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This is interesting. Shouldn't there be a property node or something that you can use to re-assign a device? The reason why I say this is that I once had to swap a DAQ card out for another one. When I went into MAX, I saw my new card there and my old one was there listed with a red X thru it. When I deleted the old card from the list, MAX automatically prompted me and asked me If I wanted to swap all my tasks and global channels over to the new device.

I was very surprised and pleased about this. There may be a way to tap into this feature programmatically.

A DDS would be illegal.

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Really?

Currently laws in many countries do not explicitly outlaw DDoS attacks but many nations are re-drafting computer use laws to make them specific offences.

So is it illegal?

You can download the screensaver from here.

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Jim, the site "http://makelovenotspam.com/" seems to be overloaded because I can't get in. Do you have the file you can upload here so me and others can get it?

The vi I have created to do the sorting via an algorithm I made up works a little better, but is still not 100% correct.

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Care to share?

It's something I just whipped up, so there may be a bug or two in there.

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I think it does. 12.txt shows up at the top of the list but it should come after 10.2.txt. Also 10.txt should come before 10.1.txt

I think you mean to say window or panel instead of Page. See here:

Creating Pop Up Panels

(btw, install openG- really useful! www.openg.org! Jim Kring rules!)

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I suggest you attend the upcomming OpenG webcast. Some exciting stuff is brewing...

Do you mean the files are not included in LV7.1, only (I suppose) somewhere on a NI-server?

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Well I guess it exists on some computer somewhere. Assuming the file exists, then I would suppose that NI would have access to it. If this all sounds very vague then it was intended to be that way.

Hrmm, thats fine for file names with set lengths, but if the directory has more complex names it again proves difficult.

Well hey, you never said "universal" I was assuming that the AB[space] was constant and the only thing changing would be the number.

AB 1

AB 10

AB 10.1

AB 10.2

AB 10.10 

XYZ 1.3

XYZ 123.4

XYZ 10.2

Really Long File Name 10.3.4

Really Long File Name 10.3.1

Really Long File Name 1.3.4

Converting each individual character from an array element it to ASCII, add up each array element's ASCII values to work out which order each element should go in, and reinsert into the array back in string format.

How feasible is this? I might give it a try :S

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You could do that but does that guarantee sorting? Don't know.

One way that will work for sure is to use a defined separator between your number and the text name. For example a dash (-) or underscore (_).

Ex: Really Long File Name-1.3.4

This way you can use my method and replace the Scan From String function with a match pattern function and just extract the number portion that way.

Here you go:

Side Notes:  All other programs that do not require the Plv.dll library work fine and the code still works on the old computer.

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Well, why not copy over the code from the other PC again?

I have no idea what Plv.dll is, do you? Is it the driver for the daq card? If so, then you need to copy or install the driver given to you from the manufacturer.

Ya, the scripting help for the methods and properties is already written however it requires some actual files that need to be installed on your computer (*.chm files etc.). The help of course is not embedded in the executable.

Those of you who were fortunate to attend this past NIWeek in August 2004 might remember a sneak peak at the new version of LabVIEW 8. Various functionality was demonstrated at a keynote.

As you can see, the development environment has been totally revamped. It looks a lot like some other text based language development environment (we won't mention names). LabVIEW 7 Express was targeted towards the newbie developer. LabVIEW 8 is targeted more to the experienced developer and the person working on larger projects. Some nice features include the ability to define various hardware environments so you can simulate attached hardware :thumbup:.

As with all previous releases of LabVIEW, NI will initiate (or has initiated) a beta program for the next release. You can line up and hope to be accepted in this beta program here:

LabVIEW Beta Program

If you really want to influence how things work in future releases of LabVIEW then I suggest you try to get on the beta program.

Sow it turns out I got involved in creating an HMI interface with LabVIEW that interfaces to a PLC. Oh joy! :thumbdown:

I started off by using datasocket and OPC to read and write values to the PLC. It turns out that this method becomes unusable for anything larger than 100 variables. The data transfer is painfully slow. This has been confirmed by NI support.

So then I convinced the customer to go with the LabVIEW DSC module. I started adding tags in the DSC engine and everything started to go well. Now I have about 320 tags setup in the engine and it is again painfully slow to transfer data back and forth. How slow? It takes over 5 seconds to get a variable change to show up in the PLC. Unbelievable!

Ok, so now I'm looking at the hardware interface to the Allen Bradly PLC. It is a serial connection at 19200 baud. Yes, I agree, this could be the bottle-neck. However does anyone out there have any experience with the DSC engine? Before I go shelling out cash for new hardware (ethernet connection). How can I make sure that this is not an inherent problem with the DSC engine and nothing to do with the hardware?

Labview is a POS.  It's hung my computer twice.  You'd think NI would get it right after 7 tries.

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What is the point of your post besides for the only purpose of bashing NI? You don't provide any information to allow anyone on this list to help you.

How do you simulate simple control on data types like integers.  I have figured out how to increment and decrement by using a feed back on a addition or subtraction function.  But how do I change the value of a variable (i.e. i = 0;)  I want to be able to reset the value of a variable to control a repeatable sequence.  This seems so basic, yet so elusive.

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It seems like you're new to LabVIEW so I hope you're not insulted by me stating the obvious. Can't you just use a numeric constant on the digram with a value of 0?

The write loop is a loop with a case statement inside. This case statement reflects different states. One state is a "user listen" state which waits for a user to hit a button on the FP. Once the event structure captures a particular button press, it goes on to unbundle a bundle of possible messages in order to select the right message to send. Once it finds the correct message to send, it creates the packet, wrapping a sync word and a checksum before and after it, respectively. Then it shoots it out to the port.

Is the unbundling taking a lot of time? I would include images of my VIs except I really have no idea what is causing this lag in writing to the serial port.  :headbang:

Thanks.

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Can you post a screenshot of the frame\case that does the message sending. Something sounds fishy. You are mixing the terms case and state. Are you using a state machine architecture or a plain event structure in a loop?

I don't mean to be G worshiper, but can't you just create what you want in pure LV without ActiveX? What features in the ActiveX status bar are you keen on? I bet I can do the same in LV.

I guess what you need to do is find out what IP address the client sees. I don't really have a good solution but I know that you can ping external resources and they will give you back your IP. One example is getting the HTML for the website: http://whatismyip.net/cgi-bin/your_ip_is.cgi

You can then parse the html and find out what your external IP is.

Damn this 7.1, since upgrading I have all of these new problems with my old working vi's.

Has anyone else noticed this problem.  My latest issue is with a while loop and stop button.

I don't think the problem has anything to do with your stop button or the loop itself. It is probably related to what happens in your code after the loop stops. What code runs after it.

I have my code inside a while loop with a "stop" button controlling the the while loop.  In 7.0  this allowed me to stop my program at will, but now it says:

Error 13 occurred at an unidentified location

Possible reason(s):

LabVIEW:  Resource file not found.

I don't really understand the resource applications of labview and was playing around with the tools->options->path menu tring to get it to work....but with no success.

Any suggestions

Azazel

Yes, well I don't think there will be anything in the options that will help you here.