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Can the USB 6225 counters be set to100% or 0% duty cycle?

April 3, 2015, 1:38 pm
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Hi,

 

I have an application with a USB 6225 and I want the customer to be able to use a slider to set the duty cycle. I'd like it if they can set the slider to 0 or 100% generating a continously on or off output. When I set the duty to 0 or 100% I get an error like this:

 

Error -200077 occurred at Property Node DAQmx Channel (arg 3) in DAQmx Create Channel (CO-Pulse Generation-Frequency).vi:4680001->Counter - Continuous Output.vi

 

Possible reason(s):

Requested value is not a supported value for this property. The property value may be invalid because it conflicts with another property.

Property: CO.Pulse.DutyCyc
Requested Value:  0.0
Possible Values:  119.209297e-9 to  999.999881e-3
Channel Name: Dev1/ctr0

 

Will setting the output to 119E-9 generate 0 output or very small pulses? If this is not possible, is there a similar peice of hardware that can go all the way to 0 and 100%?

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color sensor

April 3, 2015, 2:31 pm
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I am using an Sen 10904 color sensor and I am facing problems with it, the sensor light ON when connected but the voltages of the corresponding colors still in zero and don't change when a color is near the sensor.Please help.

 

 

afah.png

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Printing from OSX

April 3, 2015, 2:33 pm
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Is there a way to print the FP of a vi programmatically in Macintosh OSX?

 

I also want to capture a simplified image of a graph to an eps file, which seems not to be available on the Mac.

 

Thanks,

 

David

 

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Different On/Off Times for Individual LEDs

April 3, 2015, 4:46 pm
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Hey,

 

I've slowly been learning LV but I'm stumped on how to change the blinking rates for LED's.

 

I know that you can change the global blinking rate but I would like to apply different rates for individual LED's (which can be switched on/off) independent of one another.

 

For example:

 

If turned on, LED 1 will be on for 3 seconds, then off for 2 seconds, on for 3 seconds, off for 2, etc, (until I choose to stop this specific LED).

Simultaniously, if turned on, LED 2 will be on for 4 seconds, then off for 4 seconds, etc., (until I choose to this specific LED).

 

 

Any help would be greatly appreciated, thanks in advance.

 

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save 10 png images in one minute

April 3, 2015, 5:00 pm
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Hi,

 

I have basic knowlegde of how to use labview and I like labview very much. therefore, I am desperate to know how to save several (at least 10) png images (using wrtite to PNG vi) in a directory in a minute. any help would be greatly appreciated.

 

Thanks

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book for mobile robot instrumentation and measurement system

April 3, 2015, 10:15 pm
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Hello guys i seek for an instrumentation book in which foucos on mobile robot test design and measurment systems.

i will be pleasant for any offer ?

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Plotting 4D data using 3d picture control

April 3, 2015, 11:42 pm
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Hi,

 

I am using 3d picture control in my vi to view the data plotted at different locations.The 3d picture contains axis as I generated it using Create 3D axis vi But I am not able to get the gridlines on the axis to be shown on it with marker spacing(like on a 2d graph).How can I get the grids ?

I am attaching the vi in which only axis is there with data points plotted on it.

 

 

Regards

Vijayab

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code for electrode switching network

April 4, 2015, 7:07 am
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For my project, I have  16  electrodes in a circle. The electrode current switching is developed using Multiplexers. The multiplexers used in
this system are CD4067B  analogue multiplexers. Two 1:16 multiplexers (MUX1 and MUX2) are used to develop an
automatic switching system for current to inject into the adjacent pair of electrodes and take the voltage readings from the remaining electrodes

 

I have no idea how to write the code for switching the electrode pair (1-2,2-3,3-4.......15-16) and take the readings 

 

could someone help me with the code 

 

 

                                                                      ----thank you-----

 

                    

 

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how to search for array in another array ?

April 4, 2015, 7:16 am
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i want to search for array in another and when i got this array i want to take the next 5 bits  EX: array1 [ 4 8 7] , array2 [ 9 1 4 8 7 6 3 2 ] , output array [ 6 3 2 9 1]

Thanks  

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Creating FFT from 1D-Array continously

April 4, 2015, 7:55 am
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Hey Guys,

Im doing vibration measurements with a accelerometer on my mydaq. I allready get my timesignal readings correctly. Afterwards I save those readings in a 1 D array. Now I want to perform a FFT spectrum.
But the shown FFTs are useless es they are not displaying anything useful. I tried before to take an FFT va the express.vi and this worked perfectly. Got the spectra as excpected and worked fine. But as Im not allowed to use express.vi s in my project I can not use it.
So any help would be highly appreciated as Im getting nuts with it and Im trying since 3 days to get this run...

Thank you very much

LabView 2014

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liste de polices

April 4, 2015, 8:37 am
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Bonjour,

 

Je recherche un exemple pour créer une liste déroulante des polices de caractères disponibles pour pouvoir la changer pendant l'éxécution d'un VI.

Un autre problème : quand j'agrandis la police d'un nombre, celui-ci se décale vers le bas du cadre et ne reste pas centré en hauteur, ce qui limite la taille de la police. Y-a-t'il un moyen de contourner ce problème ?

 

Merci de votre aide,

Bruno.

 

 

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Count number of rising edges in 1D array

April 4, 2015, 12:36 pm
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Hello,

 

I wanted to measure the frequency of a pulse signal using an MCC DAQ through ULx libraries in Labview. I have two methods to do this:

 

1. Use analog input:

Since the DAQ has only 1 ADC, I have to use a common acquisition VI for all channels and create a multi-dimensional array with different channels in rows 0-15. Then split them using "Index Array" function.  I believe this splitting will remove the "time" parameter from the waveform, since it is now a 1D array. But I already know that it will have 1000 samples every 100 ms. All I want to do now is to count rising edges using some function and divide it by the 0.1 to get frequency in Hz, but I don't know how. Can someone help?

 

2. Use counter frequency input:

Since I can't use the DAQ assistant, I have to use the CI Frequency -> Counter 1D DBL 1ChanNSamp in the ULx library. There's no reference to take help from and I'm not sure if this method is right. I have no way of knowing since I don't have a signal generator. Plus it doesn't work so far.

 

Please help.

 

Thanks!

 

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Corrupted Excel file?

April 4, 2015, 9:35 pm
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Hi all,

I'm having problem with writing the data from my simulated vi data into Excel. After I run the Vi it works fine. But when I wish to open the excel file in which I set as the file path, it says the file extension is not valid. Why is that? Oh btw I'm still new so forgive me if this is an obvious question. I attached my VI as well as the error.

Regards,
Newbie92

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2d picture : move the origin ( 0,0 point ) to the center and draw in milimeters

April 5, 2015, 1:30 am
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I need to draw the profile of a camshaft in 2d picture and i obtained my (x,y) positions of the points on the profile in absolute coordinates. I was wondering if is possible to move the 0,0 to the center of the picture so I don't have to switch to relative coordinates since my values are extremly small ( like (0.41602,4.72796) in milimeters ).

My second problem concerns drawing at scale 10:1 as follows :

I want to print the result of the 2d picture and what i need is that 1 cm on the printed picture is equal to 1 mm in the real drawing in 1:1 scale.

 

Sorry if it makes little sense, just ask if you don't understand and i will try to explain a bit more.

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ANC FPGA for NI myrio

April 5, 2015, 1:34 am
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Hello guys,

 

I found examples of Active Noise Cancellation (FPGA) example from NI. It is designed for  Compact RIO and also using NI USB-9233. 

 

Can you please explain how to use it for NI myRIO board without NI USB-9233? What should I change in the host and also how to set I/O in FPGA. 

 

Thank you!

 

Radik Srazhidinov

 

 

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EEG Program Need Help

April 5, 2015, 2:14 am
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Hello, can someone teach me how to create this EEG program as shown in picture. this is my first time to use LabView. So, it kinda hard for me :smileysad: i dont know which controls to use. Thank You

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Error 363507 occurred at LabVIEWHTTPClient.lvlib:GET.vi:390001 - after upgrade to LV2014SP1

April 5, 2015, 4:08 am
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I am using the HTTP-tool to get the body text from a website.

 

HTTP.png

After upgrading LV 2014 to SP1 I now receive:

 

Error 363507 occurred at LabVIEWHTTPClient.lvlib:GET.vi:390001

Possible reason(s):

LabVIEW: LabVIEW could not verify the authenticity of the server.


Complete call chain:
LabVIEWHTTPClient.lvlib:GET.vi:390001
Test.vi

 

Before the upgrade this worked with no issues.


My code also works fine on another PC that does not have SP1 (but 2014).

I tried installing the Runtime-Engine 2014 SP1 on a new PC - this also fails with error Error 363507.

What is going on? :smileyfrustrated:

The website I access is a public one, freely available in any browser. So I should not need authentication.
Obviously something changed going to SP1.

 

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delay after each image saving

April 5, 2015, 4:32 am
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Hello,

 

Can anyone please help me regarding an issue I am facing. Basically, I have managed to save five image in a directory, what I now want to do is save each image after a specific delay without interrupting the whole program. I tried to do this with the elapsed time vi (under timing) but didn't get it to work. I know it is possible using this vi. I think I what I am doing is not the right way. Attached is a screenshot and the vi I am haaving problems.

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Sensor mapping - sensor locations

April 5, 2015, 6:59 am
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Hello everyone,

 

I need help regarding the use of the 3D Sensor Mapping.vi (Express vi). I can load a STL file without problems, but the manually positioning of the sensors is not a viable option in my case, so I figured I could edit the Express vi to give X,Y,Z coordinates to each sensor, but I don't know how:

 

there's a cluster named "long term sensor state" with sensor coordinates but when I change them the visualization remains the same: with the original manually placed locations. I have explored the subvis and I couldn't find where the clusters' coordinates are read.

 

Could someone help me understand how to change this subvi in order to give him specific X,Y,Z coordinates for each sensor?

 

Thanks a lot

 

Gabriel Balcells

 

 

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Error while connecting to Cloud Complier

April 5, 2015, 10:27 am
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Hey, I was trying to complie a program on the cloud compiler and I keep getting this error

 

Details:
NI-Farm Internal Error: Client received unexpected or bad data from the server.

 

I was able to compile the program about 30 mins before and it worked flawlessly but nothing seems to work now. Even programs what compiled before stop compiling. I tried turning off the firewall and that didnt work.

 

Any help would be apreciated.

I am running Labview 14 on Windows 8.1

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