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DAQmx synchronisation AO+AI+CI (Digital Frequency)

June 1, 2017, 2:38 am
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HI there,

 

I am using NI 9263 for AO, NI9225 for AI (two channels) and NI9401 for counter frequency measurements. All these tasks should be synchronised. I've seen a lot of different examples how to perform this process, but i could not get my head how to implement a frequency measurement part. 

 

I was using the code "Multi-Function-Synch AI-AO" and was trying to add a frequency code.The issue is that I can't even start the code, since my digital trigger for the frequency code does not work. I was trying different options, but without any success. AO and AI are synchronising without any complications by using this trigger, but the CI code. Is anybody able to help me with this question? Thank you in advance.

 

DAQ_synch.PNG

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ShortCut

June 1, 2017, 2:43 am
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Hello,

I just finalized my VI however I would like to incorporate a shortcut to NI MAX to facilitate the modification of the tasks.

 Regards, Jérémie DUBOIS

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Adding delay to continuous audio record and playback

June 1, 2017, 2:46 am
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Hello,

 

I'm working on a small project where we are using the Line-in of our desktop to record audio (For our test setup just a sine wave) we are then playing this back using the sound output write.vi.

 

What we want to be able to do is to add a controllable delay between the continuous record and playback. With the way that the example .vi we are using we are unclear on how to approach this. 

 

Do we need to have a form of FIFO buffer? or does labview support a vi that could achieve something like this?

 

If anyone could point us in the direction of any examples that function in a similar way or if you have build a .vi like this before any help would be greatly appreciated.

p.s We are using Labview 2010

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Acquisition tension AC

June 1, 2017, 2:49 am
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Bonjour à tous,

Je suis un stagiaire qui débute sur labview et me voilà confronté à un problème, je souhaite acquérir une tension à l'aide d'une carte NI9219. Mais avec mon programme, je constate sur mon graphe que ça fonctionne en continu, mais lorsque j'essaye avec une tension alternative (50 Hz), j'ai plus rien.

Pourriez vous me dire pourquoi, est ce un problème de réglage ? Je suis également à votre écoute pour avoir des conseils pour optimiser le graphe déroulant (par exemple qu'il soit assez rapide mais prend en compte toute variation brusque).

Je vous joins mon VI.

Je vous remercie pour votre aide.

 

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Interpolating Intensity Graph - detect shape

June 1, 2017, 4:01 am
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Hi I'm looking for help in this post. 

 

i have a sensor sheet 16X16. i connected it with jumper wires into Arduino and from Arduino through serial USB into LabVIEW. 

 

I'm using serial Read to read the analogue data streaming from this sheet and display it over intensity graph. 

 

i used an NI-Gmath/ bilinear to smooth the pixels a bit. however, i can't detect the shape of the object that i'm placing it over the sheet. 

 

for example the picture attached is my finger placed on the sheet. 

 

 

my question is, how i can interpolate the intensity graph to make it able to detect the shape of the object above those sensors ?

 

i attached my 2016 VI 

 

 

looking for help and thanks in advance 

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What is Editor Responsiveness

June 1, 2017, 5:43 am
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Hello,

 

I was  looking for improving labview vi performance as well as improving execution speed of vi. 

I found link regarding compiler setting for editor  responsiveness and execution speed

http://zone.ni.com/reference/en-XX/help/371361J-01/lvhowto/compiler_limiting_optimizations/

 

Kindly guide me what is Editor responsiveness.

I am developing application For multiple UUT  Testing.

I am using labview 2014 with NI USB 6353 x series daq card.

My main vi compiled code complexity is 3.9 .

All subvi contain compiled code complexity <1

what should  I set  compiler setting to get better execution speed.

 

Regards,

Nisarg Shah

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Any way to control whether chart plots are visible with a boolean switch?

June 1, 2017, 5:52 am
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I'm graphing a waveform chart w/ a cluster and 10 doubles, that will auto update with new data when my program loops (it should output 10 separate plots onto the same chart). 

I want to be able to choose which plots are visible. I'm sure you can do this on the front panel by going through chart properties, but I want to be able to hit a button on the front panel that causes the data to become visible. Does anyone have any ideas on how to accomplish this? Is it relatively easy/feasible (it seems like it would be)?

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Labview Holding Temperature Help

June 1, 2017, 5:53 am
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Hello,

 

I have a program that uses a PID with a square function to fluctuate the flow of heat into a system in order to keep it between the specific temperature limits. Once this target temperature range is reached I need the program to hold that temperature and sit there for a specific period of time. If someone has an idea of the logic behind this it would be greatly appreciated.

 

A couple more parameters I need implemented:

1. If the temperature ventures outside of the range I need, is there a way to pause the time until it stabilizes?

2. Another function that would be nice would be if the user inputted value for the "specific time" is zero, I would want it to skip this step entirely and move on to the next phase.

 

Thank you 

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Data card with BNC inputs

June 1, 2017, 6:10 am
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Dear NI community, 

 

I am seeking to connect a signal conditioner with 3 channels inputs type BNC to a data card NI. Do you know if it exists a data card with BNC inputs (with 3 or more inputs) ? 

 

Thanks for your help

 

Regards

 

Fanny S

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Is there a Simple Way to Detect Mouse Down event Anywhere but a Specific Control

June 1, 2017, 6:22 am
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So I need to detect a mouse down event, anywhere but a specific control.  I'm planning on doing this by obtaining references to all front panel objects which support that event (panes, controls, etc) and then registering a dynamic event so I don't have to manually add all the events to a case.

 

I'm wondering if there is a simpler way to do this, some mouse down event that I don't know about that is triggered anytime there is a mouse click, not just on a specific control?

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How to change dates of file to the windows format

June 1, 2017, 6:44 am
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I am importing data from a CSV file into an array and then getting the date. I cannot change the date format of the CSV file but when in Labview, how can i change the date format from an example of 06/01/2017 into the windows format of 6/1/2017 in Labview. The indicator being use to get the dates is Log Date.

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TDS 3014 - Ethernet - Labview : work only in debug mode

June 1, 2017, 6:46 am
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Dear all,

 

I want to control an oscilloscope from Tektronix, TDS 3014B, connected through ethernet cable, with a labview software. I thought it was an easy task as I have downloaded special VIs for this intrument here:

 

http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=163

 

I did my own code using the VI provided and I attach here my VI.

 

The problem is that the output array is always wrong! But when I go to debug mode to see what's happening wrong, the software starts working properly and measuring correctly. I give as input a 5Vdc to the oscilloscope probe, and the 5V are measured correctly in debug mode but in normal mode I measure -10V.

Anyone had the same problem? 

 

Thanks for assistance

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Oscilloscope TDS 3014 - Ethernet - Labview : work only in debug mode

June 1, 2017, 7:09 am
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Dear all,

 

I want to control an oscilloscope from Tektronix, TDS 3014B, connected through ethernet cable, with a labview software. I thought it was an easy task as I have downloaded special VIs for this intrument here:

 

http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=163

 

I did my own code using the VI provided and I attach here my VI.

 

The problem is that the output array is always wrong! But when I go to debug mode to see what's happening wrong, the software starts working properly and measuring correctly. I give as input a 5Vdc to the oscilloscope probe, and the 5V are measured correctly in debug mode but in normal mode I measure -10V.

Anyone had the same problem? 

 

Thanks for assistance

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Data transfer from one while loop to another

June 1, 2017, 6:49 am
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Hi

I am working on a project of sand plant in which image is acquired from the plant and is matched to the one in the computer using vision in labview.

I am not able to transfer the data from one while loop to other. I have attached the image below in which i want to transfer the data from "Data read 1" block to "vi to display" block in other while loop . How can i do that?

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Recount time in using function 'Elapsed Time'

June 1, 2017, 7:47 am
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Hello everyone,

 

Now I have a problem in using function 'Elapsed Time'. Here is my vi. 

In my program, when I click boolean4, elapsed time begins to count time and the boolean light is on, when it pass 3 seconds, the boolean light will be off. What I want is that when the boolean light is off, the function Elapsed Time can stop counting time and reset to 0 without aborting all the program. After then, when I reclick the Boolean 4,it starts to count time and repeats what I said.

 

Thanks a lot!

 

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Load generic vi from path without running it?

June 1, 2017, 7:50 am
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Is there a way to load vi from path without running it and without using the Call By Reference or Start Asynchronous Call functions? I am parsing folders for VIs  then feeding an absolute path to the Open VI Reference instruction. However I can't find a way to just load the VI without running it.  There is a Run VI method in the Invoke Node but I don't see a "Load VI" method only the "Run VI" method. I cannot use a Call By Reference node because I do not know the VI's interface in advance. The help for the Open VI Reference function says "If you want to use the vi reference output of this function with the Call By Reference node or the Start Asynchronous Call node, you must wire a strictly typed VI reference to this input."

 

If I can load it, how do I then unload it when I am finished with it?

 

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Error 97 in save report to file excel activex

June 1, 2017, 9:13 am
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Hi,

   So I am using both excel activex and the report generation toolbox for excel to format a document. Everytime I try to save the document I get error 97. I can seem to find why and how to fix it. The error means it's a null reference which following my code isn't true. Even when I use the save as activex method I still get the same error. 

 

Please take a look and see if you can help me figure this out.

 

Thanks

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DAQ-mx Sweep Through Frequency and Voltage

June 1, 2017, 9:50 am
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Hi,

I need to obtain peak to peak voltage level measurements for multiple voltages and frequencies. I want to sweep through all voltage levels at EACH frequency step. Any ideas how to do this? I currently am able to sweep through all voltages for one frequency point however, I cannot figure out how to sweep through all frequencies. I obtain one Vpp measurement for each setting.

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TBX-68T Pinout Ctr0/1

June 1, 2017, 9:59 am
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Hi Guys,

 

I have a TBX-68T breakout module, I configured it on the my DAQ card and used the digital i/o to flip the bits on the J12 using the test panel in NI MAX, works fine. I then selected the counter option and configured a periodic pulse using ctr0. The GUI provides all the options, but doesn't mention any of the pins on the board. I don't seem to be able to find the ctr0out pin, or any documentation that explains where I might find it. The Datasheet doesn't mention the counters, although it does mention the PFI mappings, but the PFI mappings aren't declared in the pinout either...

 

Do I need to setup a routing in the Labview tool to allow a ctr0 output from the TBX-68T?  Can the TBX output a counter waveform? Do I need to use a CB-68LP or equivalent to get access to the signal? the TBX is very much what I have available right now, I'm aware it's a fairly specialised analogue in device, but the pinout details seem rather scant...

 

Anyone help?

 

Rob

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Is there a way to Share Data Between Custom Probes

June 1, 2017, 10:34 am
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I'm trying to create a set of custom probes which allow me to time sections of code without having to add code by setting an entry point probe and an exit point probe but to do that, the start time obtained by the entry point probe needs to be accessible by the exit point probe and ideally without doing something slow like writing to a file.  But perhaps this isn't possible due to how probes are executed in LabVIEW?

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