Tim_S

QUOTE(bayram_mercan @ Jan 24 2008, 05:57 PM)

i'm getting thermocouple data from a NI board. but also i want to get exact time like hh:mm:ss and also miliseconds. because i get 100 samples per second. how can i do that? also why my task gets last 100 data?

You're getting 100 samples back because that's how many you've configured the DAQ assistant to return. I suspect that 100 samples is the default and it wasn't changed.

I'm not sure what you're looking to do with getting the exact time. Are you looking to have a timestamp for every sample? For the start of the data? For the end of the data?

QUOTE(eoin @ Jan 24 2008, 01:37 PM)

Sorry for not being specific enough, The gateway is a comsoft FNL which i think uses an OPC server.

OPC shouldn't be hard. If you open up the NI Example Finder and search for OPC you'll find several examples, plus there's shared variables.

Tim

QUOTE(eoin @ Jan 23 2008, 07:42 AM)

I need help getting labview to communicate some digital and analogue I/O over ethernet to a gateway which then communicates with profibus.

How to go about getting the Values in my labview VI to communivate over ethernet?????

Ethernet is pretty vague as it's a hardware protocol. What software protocol does your gateway use to communicate? It could be EthernetIP or ModbusTCP or something in swahili. Does the gateway have an OPC server?

Tim

QUOTE(Raquel @ Jan 22 2008, 06:42 AM)

Hello everyone, I am trying to read temperatures from thermistors with labview. however I can not read the right temperatures since I know that the real tempertures are about 10ºC and 30ºC, and labview is reading negative tempertures! can anyone tell what can I be doing wrong?

Thanks

Raquel

You've not included anything about the hardware you're using nor any code, so it's not really possible to provide any useful advice.

Tim

QUOTE(dsch @ Jan 21 2008, 04:12 PM)

This will be part of a bigger system. I'm not sure the PCI DAQ cards are capable of supplying 12VDC. Do I use the analog output? That's only 10 volts max on the cards.

Here's one of the cards I was looking at.

http://sine.ni.com/nips/cds/view/p/lang/en/nid/201612

You'll have to use a separate +12VDC power supply. I wouldn't try powering anything from an analog output as I doubt it has sufficient current capacity nor does it go to your 12 volts. The card has the pieces you mentioned.

One thing you may want to make sure of is that the valve you're using has the proper electrical isolation to protect your DAQ card and PC. From what I've seen, most manufacturers are assuming their equipment will attach to a PC nowadays rather than something significantly more rugged.

QUOTE(YaSmEeN @ Jan 19 2008, 05:13 AM)

Hi every body...

I have a project and I want to run a machine (i.e. pump) and I have a table that contain two columns( the date and the quantity of water) in excel.

so how I can run the pump as the data in table...

would really appreciate if anyone can give me any help or point me to the right direction; because I urgently need to produce my work ..

Thanks

From the controls standpoint, you're missing hardware or information; once you have the values into your program, how do you control the pump to provide X units of water. I'm guessing that's not a concern and that getting the information into your program is. On that, I see two methods of doing so: 1) have LabVIEW open the Excel file using ActiveX, .NET, etc., and read the information in using that link, or 2) export the information from Excel into a text file then have LabVIEW read the text file.

QUOTE(dsch @ Jan 19 2008, 07:56 PM)

I have a solenoid valve with a 9 pin D connector. Power is 12VDC, another pin is digital (TTL), another is analog (0-5VDC). I would like to to use Labview to create a program to manipulate this valve.

Has anyone gone through this before? Can someone recommend a reasonable controller that labview has drivers for? Ideal scenario would be a pci card. My searches haven't been successful and this isn't yet my expertise.

-TIA

From what you describe, you're going to be soldering up a cable. Have you tried looking at National Instruments' website? They sell hardware as well as LabVIEW.

QUOTE(Natu @ Jan 20 2008, 05:39 AM)

Mross and Tim_S

First of all thanks for prompt response from your side. since i am going to make one operator training simulator (OTS) for power plant, based on the labview. To implement the logic for pump, valve etc. I need very much this set reset Flip-Flop. And I have already made one set reset Flip-Flop attached here. But problem is that I can used that saved set reset Flip-Flop only once. If I will use second time this same set reset Flip-Flop by copy and paste method then both will work together, but not independently. I have made same as a SubVI but problem still same I can not use more than one place. That's why I was asking a method by which I can use self made set reset Flip-Flop any number of time independently same way as we are using other function palette elements like AND, OR, NOT gates.

Mike... I'll remember that students use this board in the future.

Natu... If you open up the VI properties and go to the Execution category, I think you'll find what you need. By default, one copy of a LabVIEW VI exists no matter where it is placed in a program. This is desirable for most cases. However, there are cases such as what you're describing, where you want one copy of the VI to exist per use in your application. In LabVIEW this has been called "Reentrant execution".

QUOTE(Natu @ Jan 19 2008, 01:41 PM)

I want to make RS flip flop and then i want to use that flip flop same as we are using Logic Gates from Function Palette. Please give the Idea.

Creating a flip-flop involves a clock and logic gates. The information on these is redily available. For an RS flip-flop, a good gate diagram is at http://www.play-hookey.com/digital/rs_nand_flip-flop.html

I've attached an implementation of an RS flip-flop based on the site. You'll still need a clocking source. Note that the flip-flop has to see both edges of the clock before it fully changes state with this implementation. Also attached a second (simpler?) implementation that clocks on the falling edge of the CLK signal.

QUOTE(TobyD @ Jan 17 2008, 02:59 PM)

OK, I figured out what I was doing wrong. Forgot to wire the image depth into my image data cluster :headbang: . Sorry for the ugly code, I threw it together quickly while enjoying a cheese sandwich .

Set image depth to 24 for best results.

http://lavag.org/old_files/post-8758-1200599970.vi'>Download File:post-8758-1200599970.vi

Ah! I was using an image depth of 32 and that was messing things up for me. Thanks for the assistance!

Tim

QUOTE(TobyD @ Jan 17 2008, 01:41 PM)

I couldn't make it work, but perhaps you can. It sounds like you have figured out the first part of this VI already. It also includes a scripting method that returns an image from the system clipboard (different than the LabVIEW clipboard). I was able to get an image that was somewhat recognizable, but everything was yellow and magnified. You can play around with it.

http://lavag.org/old_files/post-8758-1200595015.vi'>Download File:post-8758-1200595015.vi

Yes, the first part looks recognizable. I don't see a "Get Image" under the clipboard, so I assume there's a flag I've not set in the LabVIEW ini file. Taking the data into a Draw Flattened Pixmap produces an interesting image, but not a correct image. The results remind me of interlaced image files.

Before I forget again, thanks to everyone who is helping!

Have a look at the Code Capture Tool.More info is in the wiki Code_Capture_ToolThis provides a User Tool in the 'Tools' menu and an API for programmatic access.Ton

In 10 minutes of playing about with SnagIt, I'm impressed with the user interface and the apparent ease of use. However, it doesn't appear to have a programmic interface, which is what I need (lousy customer specs!). There is an registration for ActiveX for SnagIt (nothing in .net), but the property and method nodes were empty.

I'm looking to perform a screen capture and am having some difficulty finding how to do this. By screen capture I don't mean a single VI's front panel, but the entire display.

I found an example that simulates using the print screen button to capture the display to the clipboard. This worked when I pasted into paintbrush, however reading the clipboard in LabVIEW returned a zero length string. Searching resources hasn't produced any other information on how a screen capture of the display can be done. Ideas I've had appear to have run into walls.

I'm using LabVIEW 8.5 on Windows XP.

Anyone have ideas? (Dare I hope for sample code?)

QUOTE(Tomi Maila @ Jan 16 2008, 01:48 PM)

I'm using a reference that is opened with open application reference. However it's opened outside the scope of my code.

You assume wrong. The part of the code I'm working on only knows the application reference and doesn't know how it has been opened previously.

I'm using LabVIEW 8.5 or newer.

From a bit of poking about, it appears that all of the information you're looking for is blocked from any remote access. I think the sugestions of the local application publishing the information in some manner (TCP, UDP, front panel, shared variable, etc.) to be your best solution.

I'm assuming you're using the open application reference, though I've noticed that you could be using the TCP communication or similar as well.

Looking at the Open Application Reference, you have to know the machine name and can optionally add the port number when making the connection from A to B, so I assume you know both of those at A. You'd still need to get that information to C, though if you all ready know this information at A to where you can make the connection in the first place, then why don't you know it at C?

What version of LabVIEW are you using? You may be able to use shared variables to have B publish the needed information to where A and C can access it.

Tim

QUOTE(Tomi Maila @ Jan 16 2008, 07:30 AM)

Hi,

Assuming I've a network of multiple computers, say A, B and C. On one computer A I've a LabVIEW application App_A running. In that application I've a valid reference to a remote LabVIEW application App_B running on a second computer B. Is it possible to find out the ip address and the port number of that application App_B from the valid reference in App_A. I need to be able to open a reference to the same application App_B on B from computer C. I need to somehow pass App_C on computer C sufficient information to connect to App_B on computer B and the only thing I've is the reference to App_B valid in App_A only.

Tomi

I've used both methods and which I've used depends on what the dynamic VI is doing. If it's something that I'm going to run once, I set the front panel control values and then run the VI. If it's something that's going to loop in the background, I may pass some initial values (configuration files path, for example) and then pass information to it using events, queues, and LV2 globals. The method I used depended on the application's structure and the nature of data to send. For example, error handling routines get their information from a queue so all the errors can be handled at once while a value that can be set from or used in multiple points in the application goes to a LV2 global.

This what you're looking for?

QUOTE(thevoiceover @ Oct 3 2007, 02:18 PM)

I am curious on if anyone has anything that could convert HSL to RGB for me that I could run in some LabVIEW code.. I could have sworn I had a .dll way back that did this, but I can't find it... I couldn't find anything in LV that did this either... I am running 7.1.1