LabView and 3rd party USB

[Mubi]

Hello

can you please tell me that how can i input a floating point number at the input of the divider (as you did in example reply 35) and if at the output i get a value suppose 4.4 how can i draw sinwave from that output in LabView. (because i tried to plot that voltage but it gave me a straight line at 4.4 rahter i need a sin wave) 

[smercurio_fc]

You are not listening. The Call Library Function Node has to be inside the loop. How else are you going to continuously get data?

To change the representation, right-click on the constant and select the Representation menu, as detailed in the Help.

Your questions are very basic LabVIEW programming. Have you gone through the tutorials. To learn more about LabVIEW it is recommended that you go through the tutorial(s) and look over the material in the NI Developer Zone's Learning Center which provides links to other materials and other tutorials. You can also take the online courses for free.

[Mubi]

Hello,

I am giving the Input voltage (6 Volts) to my measurement board and I am trying to read the input voltage of the board from the LabView through the "Call Library Function Node" .

Problem:

If I change the input voltage and read it from Labview it always return me the same data in two bytes, even if there is a large variation in the input voltage,

Question:

Why I always get the same data bytes (2 bytes data) even I change the input voltage from 5 to 8 volts? I am attaching a picture please have a look.

Best Regards,

[Dennis_Knutson]

This whole thread has gotten very confusing. You've talked about a dll and also .net. Do you really know the type of dll that you have? Since you have not provided any documentation on the dll or hardware, I don't know how you can expect anyone to help. There may be a different function you need to call or perhaps you are calling this function incorrectly. Have you requested help from the vendor? They would be the best ones to ask.

[smercurio_fc]

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Mubi wrote: Problem:

If I change the input voltage and read it from Labview it always return me the same data in two bytes, even if there is a large variation in the input voltage,

Question:

Why I always get the same data bytes (2 bytes data) even I change the input voltage from 5 to 8 volts? I am attaching a picture please have a look.

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I can't do anything with that picture. I had indicated that in order for you to see a change (if one happens), you need to be calling the function continously. This means it has to be inside the loop. In your last program you still had it outside the while loop. If you still have it outside the loop, then I can't help you because you're not listening. If you have it inside the loop, then as Dennis suggested you need to contact the vendor because we don't have the DLL, or the documentation, nor can we even use it because we don't have the hardware. 

[Mubi]

Hello smercurio_fc:

when my program was not in the loop that was the reply "41", I definetlly improved my VI after, as you sugested that mean I am listening to you.

and Dennis suggested me may be I am calling the wrong function but as I read the output voltage then it works ok but when it comes to reading input voltage then I always get the same bytes as I mentioned in the last messege. So I was wondering if the problem is in the "call library node "in LabView or the problem is in the boar. and I always appreciate your help.

Thanks.

[Dennis_Knutson]

The 'reading the output voltage' and 'reading the input voltage' is meaningless to everyone. You still have not provided any real information about the hardware or software. It could be anything.

[Mubi]

Hello ,

Actually I have the evaluation board that is "3ECMM" and there is a DC-DC converter mounted on it. I got the user Interface for that evaluation board. But I want to control that board throug LabView. In order to do that I called the .dll file which was the C/C++ DLL, from the labView by using the call library function this was the breif introduction what I m doing. I am using the Zilker Labs PMBus Interface.

and what I want to do is  to Monitor and Controll the DC-DC converter's output aswell as check what is the input voltage ,Device temperature etc of that device, I am giving the voltage from the fixed voltage supplier to the board and trying to read that voltage from the LabView. as I am communicating/controlling the PMBus through LabView by using the Zilker Labs PMBus command set. I am suppose to get the voltage or temperature of the board in two bytes in LabView. So I am trying to monitor the output/input voltages of the board through LabView.

As I described my problem in message 43 before. I just wanted to have some idea what can be the possible problem in my case. and as you said 

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Dennis Knutson said

The 'reading the output voltage' and 'reading the input voltage' is meaningless to everyone. You still have not provided any real information about the hardware or software. It could be anything. 

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As the question about the hardware and soft ware, I can tell that I am using a 3E Evaluation board and a POL (Point Of Load, DC-DC Converter) is mounted on that board and I want to communicate to that board through PMBus using LabView. I made a VI to do this task which can read the parameters of the PMBus in LabView. so when I read the output voltage its working and when it comes to input voltage i always get the same values on the required bytes. Please let me know specifically if you want anyother information or document.

[Dennis_Knutson]

And do you expect the people here to do the research on 3ECMM and PMBus? Can't you attach some actual documention or at the very least, provide some links to the documentation of this hardware and software?

Even with proper documentation, I'm still not sure you can get much help from anyone here. It would seem to be more appropriate to ask the vendor about problems with the dll since we do not have the hardware.