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Re: purchased educational version but only get option to download trial version...

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I agree that that dialog can be a bit confusing, but both links will most likely bring you to the same download. It does not matter what you click here, but the answer is probably used for statistical tracking and determines what kind of detailed instructions you receive in the next screen.

 

All version are the same download, and if you don't activate you can try it for 7 days (this time can even be extended).

 

So the question is if you received an activation code. Did you? That's the only thing that matters. Once you activate, the trial version will turn into whatever version your license allows.


Re: Multiple netstream clients in a reentrant VI

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confra82 wrote:

Many thanks Bob_Schor for your suggestion,

By the way, never attempt to open two network stream toward the same address.

The behaviour of the VI deceived me.


Oops.  In my LabVIEW RT project, I have 4 (> 2) Network Streams connected to the same address.  Two form a bi-directional Message Channel, and the other two stream sampled Analog Data (synchronous, known data rate) and "Event" Data (asynchronous, "when-it-occurs") from the Remote to the Host.  Of course, all of the Streams have unique names ...

 

Bob Schor

Re: Set the Pane Origin

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I will take no credit for this VI but NormK uses the attached VIs in the TLB' architecture which has some additional functionality (it also works by just putting it on the BD like yours). Hopefully that saves you writing additional functionality yourself.

 

Also, if I remember correctly, there is no need to close panel references as they inherit from GObject and will be a non-op.

Re: Unable to use I2C on Arduino Nano in LabVIEW

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I fixed the issue. Everything randomly started working once I uninstalled and reinstalled the FTDI USB drivers for Arduino Nano. 

Re: How to compose an arbitrary waveform for DAQmx?

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That isn't a medical issue, it's very simple, first of all I write faster than i think. Second I am from Spain, and its very very hard to know talk and write in 3 language (English, Catalan and Spanish), and for being more complicate, technician language is more harder. Sorry if talk like 3 years old kid.

GerdW thanks to open a new thread, I really appreciate it. In the darknes of ignorance you are a beacon of light. Thanks!

Re: Critique my loop to send a text file, line by line or en masse?

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¡Hola! and thank you both for your suggestions.

 

Yes, the shift register in place of Line Counter local really cleans things up. For some odd reason I was confusing a shift register with an auto-indexing something-or-other, and I didn't realize I could control the incrementing with the Case. It looks slightly cleaner now:

 

SendFileSnippet2.png

(the False cases are both empty, except for a straight-through wiring of the shift register)

 

I could try to get rid of the remaining local variables and perhaps one of the buttons by using a latch (which would also get rid of the outer sequence), but I did want to retain the existing behavior, which enables:

  • Sending one line at a time, and/or
  • Sending the file all at once, either from the beginning or from a pause, and/or
  • Pausing in the middle of a mass-send.

If I get rid of Send and just pause or not-pause, I won't have fine control over sending one line at a time. But I'm all ears if you have a suggestion in this regard!

 

Could I use a classic For loop with an event-driven pause? That would eliminate the Line Counter and just auto-index through the string array, wouldn't it? I actually started out with a For loop, but couldn't figure out how to pause/resume it, which is why I switched to a While/Case structure. 

Re: Kithara: Error in Process Attach

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Kithara is a third party real-time software for Windows, and I'm not sure why that error would occasionally pop up when you open up your LabVIEW application. Just taking a cursory look at the website, it should be compatible with a Windows 10 64-bit OS. I wasn't able to find much information about this error internally since it's third party specific, so unfortunately I can't offer a lot of insight. It might be more helpful to contact their support to see if they have seen this error before.

Re: Unable to configure Xilinx IP block

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Do you have the Xilinx IP Datasheet? 

Are you using the Xilinx IP Node? Which function from the Xilinx IP palette are you using?

If so, what kind of configurations are you doing to this Xilinx IP?


Running Average of DAQ Assistant that Automatically Records Data At Specified Time Intervals

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I wrote a program that reads data from a DAQ Assistant, calculates the moving average, and then writes the data to an Excel file for 5 minutes every hour. The problem is that the sample rate in the written data is far less than the requested sample rate in the DAQ Assistant (1 Hz recorded vs. 100 Hz requested). This issue is related to the 'for' loop that calculates the running average because the program doesn't have this issue when the running average calculation is removed. Why does the 'for' loop take 1 s to output a value?

 

Is there a more efficient way of calculating this moving average? I cannot use mean ptbypt because I only have the base version of LabVIEW.

 

Thank you very much for your help.

Re: Projectile motion

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This has nothing to do with LabVIEW, BUT...

 

If you shoot a projectile with a launch angle of 90deg (straight up in the air), it should come down on your head. Your result shows it landing quite a long distance away. So, I think your equation is wrong in the Matlab Script.

 

script.JPG

 

Got this equation from Wikipedia

 

equation.PNG

 

Rearranging the terms to match your MathScript code, I get the following for "R":

 

R = d.*[sin(a)+A]

It's different than what you have. Try it and see if the results are more realistic.

Re: Capturing STOUT/STDERR from C DLLs

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This actually appears to work with my test case.  If I just make a call into the dll to setup the redirect, then it appears as though the rest of the calls into the dll will have their stdout routed to the pipe I'm reading. 

 

This I believe resolves my issue. 

 

Thank you again.

 

 

Re: Running Average of DAQ Assistant that Automatically Records Data At Specified Time Intervals

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Hi Sean,

 

This issue is related to the 'for' loop that calculates the running average because the program doesn't have this issue when the running average calculation is removed.

Well, it's more related to your use of ExpressVi and DDT wires…

By converting a DDT wire to an array of samples you lose the timing information. When converting back to DDT the default timing of 1Hz is applied!

 

Recommendation: get rid of ExpressVIs. Or apply the correct timing information…

 

On your VI: why do you convert the DDT to an 1D array while processing just the first sample with your FOR loop?

Re: Critique my loop to send a text file, line by line or en masse?

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Whoops! Minor error on that snippet. The While control should be Stop, not Run. I must have inadvertently clicked it while I was trying to align everything nicely. Corrected version, here:

 

SendFileSnippet2.png

 

 

Re: Critique my loop to send a text file, line by line or en masse?

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Here are some suggestions:

  • You don't need the Shift Register/Counter line at all -- use the "i" Index variable of the While Loop (which starts at 0 and increments by 1 each time through the loop).
  • If you rename/rethink the "Pause" button and make it a "Single/All" button (True if you want to send All the values, False if you want a Single value), then both controls will initialize (by default) to False, so you don't need to initialize them using Local Variables (unless you run the program, then re-run it without re-setting the Booleans).
  • I'd rename the Send button to "Run" (meaning "When I push this, Run the code").  Note that if you are doing one-at-a-time, you'll need some logic to latch (via a Shift Register) a Boolean so you only do the loop once until you either turn Run off or change Single to All.
  • With the above changes, you can delete all of the Sequence Frames, and let Data Flow do the sequencing for you.
  • The Stop button should end up being wired to the Stop (not the Continue) indicator.
  • Code like this seems (to me) to beg for a Queued State Machine, with the Queue being driven by an Event Loop that handles the three buttons (oh, yes, I forgot -- I named the "stop" button "Abort", as you use it to end the program, "aborting" it, before it finishes).  This would allow you to eliminate the "busy-wait" 1 ms delay in your loop.

Bob Schor

Re: How to compose an arbitrary waveform for DAQmx?

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Hello! Again!!

The first problem that I have is that TDK lambda power supply hasn't isolated analog I/O to control them with a NI device. I was wondering if the USB DAQ of the 60xx family has some device with isolated analog I/O or if there are any way to solve the problem of conecting the USB DAQ 6008 to an non-isolated analog I/O, like making an electronic circuit as an interface betwen them with any special configuration... I was searching a bit for NI device and it's hard to find something economic.

Thanks!


Re: DLL access violation - unless caller's FP is open.

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rolfk, I was hoping you'd take a look; thanks for the reply/appraisel.

The "external" vendor seems clueless regarding software design.  They actually supplied several unique DLLs - one for each unique board ID.

That said...

A single copy of the current DLL functions "rock-solid" (at least it's hard "crap") and I need to make the two-copy system work.  I'm not 100%sure the DLL is doing anything wrong!  Perhaps an errant process, elsewhere in the app, is attempting to "stomp" on the DLL's memory...  

Re: Excel to Labview

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Yes, that sounds right to me ...  Thanks.

Re: Critique my loop to send a text file, line by line or en masse?

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But doesn't the While loop run continuously, regardless of the buttons' states? That would cause my index/line counter to increment even when I'm not sending. Or is there a way to control that, as well?

Array selection start selection end

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How is this context menu used on an Array (right click on an array, not the array-item, in a runtime LabVIEW). A blue line or box appears when Select All but not sure what to do with the "Selection Start" or "Selection End" on the Array context menu while the VI is running.

 

Can I select array item(s) and get them out of a property or on the clip board etc.....

Brainstorming and looking for ideas

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Hello,

 

On our manufacturing floor we have many consoles that contain Keithley Switch/DMM's. We use three different models of these instruments the 2700, 2750, and 3706A. The 2700 can contain up to three plugin switch modules, the 2750 can contain up to five plugin moduels, the 3706A can contain up to six plugin modules. 

 

Keithley provides a means to access the switch closure counts for each switch on each plugin module. This helps with preventive maintenance we can see if a card or relay is coming near its life expectancy. Currently we have two utilities one for the 2700/50 and one for the 3706A. Our technicians periodically go out and check each console that contain one of these instruments and notes the highest count returned for each plugin module in that switch mainframe.

 

I am looking to reduce the effort that is currently necessary to perform this activity on our floor. 

 

I would like to create an application that would reside on the PC in each of these consoles. This application would periodically query the switch mainfraim for the switch counts for each plugin module in that mainframe. This application would then report the max count from each module up to a server application that would package the information from all of the reporting consoles into a format that would allow the person looking at the data to easily discern which module in which console might be getting near it's end of life. The server application may also be able to send out an email to specified personel when a module max count crosses a defined threshold.

 

Any ideas are appreciated. If you have already created a system like this even more so.

 

Thank you in advance and have a great day! 

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