Quantcast
Channel: All LabVIEW posts
Viewing all 202367 articles
Browse latest View live
↧

Re: Waveform+Chart+Array Average

March 27, 2018, 7:00 am
$
0
0

Sir, 

I misspoke earlier sorry. So we need to find the average of the data points that shows on the graph.
So, after we hit stop to button on the while loop, the loop should stop running and then we need to take the average of the data that were converted to Celsius and plotted on the graph. I think we need to create an array at the output and show all the points that were converted using a indicator and then take the average of it. i tried few different ways and keep getting broken wires. I really appreciate your help. Thank you again 

↧
Search

Re: Creating channels for typed-in user input in DAQMX

March 27, 2018, 7:01 am
$
0
0

Hello meierdh

 

I saw your VI, do you mind walking me through it a little bit. I assume that the first section is you creating all of the channels and the while loop is the one responsible for acquiring the data. I also saw that you created all of the channels in the same task, is there a reason for you to do that?

 

Regards

Sebastián

↧
↧

Re: Waveform+Chart+Array Average

March 27, 2018, 7:03 am
$
0
0

Also, i only want to display the temperature in Celsius on the graph. The solution that you have provided earlier plots the temperature in Fahrenheit since you connected the array constant (in F) directly to the array builder. Please let me know if i am wrong.

↧

Re: Updating a reference stored in a SubVI

March 27, 2018, 7:06 am
$
0
0
wrote:

The thing with parentheses is that you should be able to completely remove them and retain the original general meaning (and correct grammar) of the sentence in which case "make the reference control a type def" is relatively clear.

 

I think of all people, Ben is aware of the power of images over text.

 

My other question is how did Ben manage to post that without a certain word being bleeped out of the text?  NI's filtering for uncouth words is normally so over-zealous.... Smiley IndifferentWhat's your secret Ben, tell us please?

Computers are smarter than t you think. The filter monitors what you are thinking you type and not what you actually typed. In the example above I was thinking "pass" so the filter was not triggered.

 

Not that complicated after all.

 

While seeds and plants do care if you plant them upside down, they never object to syntax errors. I can only dream of a day when my spelling and typing are no longer a factor.

 

 

Smiley Wink

 

Ben

↧

Weight management

March 27, 2018, 7:12 am
$
0
0

Good day everyone,

I am fairly new to LabVIEW interface and this problem might not even a "problem" to pros.

So my task is to create a system that calculates remaining weight. First, the user will enter the maximum weight available. Then, as we enter a weight value, the available weight will be decreased. The process will need 4-5 weights to be entered. I really need your recommendations on how to do this.

Thanks in advance!

↧
↧

Re: Analog input-output FPGA

March 27, 2018, 7:17 am
$
0
0

The data you retrieve with your DMA transfer is un-scaled raw data. The format is signed-integer 16 bit so has a range of +/-32768. This is the raw data of your A/D converter.

 

As you can see in the Host VI from the original example, the AI Vertical Range is given as 2.03 Vpp (to the left of the while loops). It means that 2.03 V corresponds to your ADC range of 65535, thus 0.5 V corresponds to approx 0.5 / 2.03 * 65536 = 16142 and that is pretty close to what you see on your graph.

 

To convert your data to 'volt' use the Scale Acquired Data sub-VI from the example host VI (inserted between DMA Read and the graph.

 

The periodic distortion in your signal may be present on your generator, can you try to check the waveform with an oscilloscope while still connected to you adaptor module.

 

The waveform jump on your graph is likely due to either buffer overflow (you should receive an error on your host side) or that you have not emptied your buffer before re-launching your VI so you get 'old' data from a previous run.

↧

Rif.: Convert build script in LabVIEW not 2014

March 27, 2018, 7:20 am
$
0
0

It's been removed. Probably they where fed up with it after 8 new versions of LabVIEW...

 

They did not remove it from the help, and that is a bug.

 

It's not just the menu that is missing. It used to be in "National Instruments\LabVIEW 2013\resource\Framework\Providers\Builds\AppBuilder\ConvertBuildScript", and there is nothing like that in 2017...

 

Guess you have either read in in Notepad (not sure how that will work) and convert it manually, or find a <2015 version (not sure how that will work either). For a lot of applications simply starting over will be the shortest path.

↧

Rif.: Convert build script in LabVIEW not 2014

March 27, 2018, 7:27 am
$
0
0

Yes, I use LabVIEW 2014 to create a project starting from the build script and then this project can be opened in every later version of LabVIEW. I was just curious to understand if it is a hidden feature or removed.

Now I know that it was removed.

Thanks

↧
Search

Re: Waveform+Chart+Array Average

March 27, 2018, 7:30 am
$
0
0

Hi Alyssa,

 

Please let me know if i am wrong.

You are right.

 

When you have problems with your VI (like "broken wires") you should attach that VI to get help on it!

↧
↧

Re: Can I embed web publish tool product to another Web technology like Nodejs, Asp.net

March 27, 2018, 7:31 am
$
0
0
wrote:

I have project that use web publish tool with monitor mode.
I now that its mechanism is send an image from server to client every 1 second.
And some question bellow:
- Can I embed web publish tool product to another Web technology like Nodejs, Asp.net 
- Can I modify its frequency under 1 second.

- Is there any authorization mechanism here
Thanks for take a look at this

How should we know what a web publish tool can do without even knowing what web publish tool it is?

 

Where does LabVIEW come in?

↧

Re: Analog input-output FPGA

March 27, 2018, 7:35 am
$
0
0

Thank your very much for all this help !!

 

I fixed the probléme with the graph by using the Scale Acquired Data and it works now ( i have the real value in the scale).

 

For the waveform deformation: I linked the generator with the oscilloscope directly and I have a clean signal, so the generator works perfectly.

For the The waveform jump , I do not understand your explanation ( buffer overflow )..

 

↧

Re: Weight management

March 27, 2018, 7:36 am
$
0
0

Hi Qii,

 

First, the user will enter the maximum weight available. Then, as we enter a weight value, the available weight will be decreased. The process will need 4-5 weights to be entered.

- So you want to get the difference of two values? Use a subtract function!

- you want to repeat a certain task several times? Use a loop!

- you want to keep a value for the next loop iteration? Use a shift register!

 

General hint: Before starting to code you should create an algorithm. Draw that algorithm on a sheet of paper. (Yes, paper and pen…)

↧

Re: Wanted: Data historian recommendation (i.e. DSC replacement)

March 27, 2018, 7:37 am
$
0
0

Citadel maybe? I know it's part of DSC, so probably not what you want. But it should be able to stand on it's own. Not sure if you can (or have to)  purchase it...

 

I'd guess that any OPC Historian (google) would try to tick those requirements. Not sure how successful they are, you're list is quite long...

↧
↧

Re: How to implement callback function when DLL file is called

March 27, 2018, 7:40 am
$
0
0

Thanks for your answer, but I still don't understand it. Is there a similar example?

↧

Re: Melleable Vi Application builder Errors

March 27, 2018, 7:46 am
$
0
0

I have the same problem building PLLS.  when i added "number to enum.vim" i started getting error 13s when building.

 

i removed the help path in the vi properties as somebody else stated and the problem is gone.

 

should this have been fixed in version 17.0f2 (32-bit)

 

↧
Search

Re: Network-Published Shared Variable connect with TIA Portal

March 27, 2018, 7:49 am
$
0
0

For questions about the TIA, I would contact Siemens support or post in their forums.

 

That said, NI provides a free tool to monitor NPSVs called the  NI Distributed System Manager that is likely already on your computer (though you'll need version 2015 or order to be compatible with the NI-FieldPoint driver and cFP hardware). You can use it to monitor system resources including NPSVs. Visit the DSM Help pages to learn more.

 

Additionally, our cFP hardware has reached end-of-life and support will become increasingly limited. Consider transitioning to our CompactRIO platform for long-term project success and for access to updated support resources and examples.

↧

Re: Melleable Vi Application builder Errors

March 27, 2018, 7:49 am
$
0
0

the official solution doesnt solve the problem for PPLs!  you have to use the other solution presented in this thread which is to open the vim you used and remove the help path from the vi properties.

↧
↧

Re: Analog input-output FPGA

March 27, 2018, 7:57 am
$
0
0

Did you check the generator with your scope while the 5783 was still loading as well? The 5783 has a 50 ohm input impedance so I wanted to make sure your generator can drive a 50 ohm load.

 

I cannot look at your actual project right now...

When you start your acquisition the FPGA will immediately stream data to its relatively small FIFO. If you are not able to retrieve this data (DMA to Host) fast enough, the small FIFO will overwrite itself and that could explain a waveform like the one you see. There are error flags you can use to check for any overflow (both on the FPGA - a Boolean on your FIFO node - and on the host side). Make sure to monitor these to catch eventual timing issues.

 

Also if you pause or stop your host VI, you may still have data stored in the different FIFOs. If you don't clean (empty) your FIFOs when you re-launch your host VI, you may retrieve old data first. Another possible explanation for your jumping waveform. In any cases, correct error handling should help you identifying possible issues.

↧

Re: Waveform+Chart+Array Average

March 27, 2018, 9:57 am
$
0
0

2.PNG

 

I have used sequence structure so that the mean is calculated after the loop is stopped. Also i know that i converted the temperature twice by introducing expression node on the second sequence. i will fix that. regradless of that i get a broken wire Smiley Sad

↧

Re: Waveform+Chart+Array Average

March 27, 2018, 10:02 am
$
0
0

Hi Alyssa,

 

What's the point of the sequence structure here? Dataflow is already ensured by the loop border...

 

Right now you output a scalar value out of the loop: what's the point of calculating a mean from a single value??? (Did you read the error explanation for this broken wire in the context help?)

 

Did you already take the beginner courses?

↧
Viewing all 202367 articles
Browse latest View live
Search
<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>