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[QMH] Having a state repeat until a condition is met (without blocking)

February 8, 2018, 5:51 pm
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Hello all!

 

I'm using a QMHarchitecture to control a robotic system.  I'm still learning more and more about the QMH programming architecture.  I have a total of 4 queues, currently:

  • UI
  • Serial Data
  • DAQMx Tasks
  • Datalogging

I have some laser sensors that will output a boolean if there is something in front vs nothing in front of them.  I also have a series of commands that I send to the various queues (haven't gotten there yet, but getting close).  My question is: How can I create a state (in the "tasks" queue) that will repeat itself until the lasers' booleans become true (then, move on to the next queued element).

 

Thanks,

Joe

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Error-1073807338

February 8, 2018, 1:43 pm
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Afternoon,

   I'm currently supporting a client on site who is getting a VISA driver error message. The error starts as "Error - 1073807338 occured at VISA. Clost in Advanced Serial Write and Read.vi SubVI2.vi-> MAIN PROGRAM.vi". I've attached an image and the error log file. Any suggestions is gratefully appreciated.

Best,

   Joao da Silva

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How to get waveform data in specific duration?

February 8, 2018, 7:03 pm
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Hi,

I have an analog waveform and I want to get the data in 20ms range (Like, 0ms-20ms then 20ms-40ms .........)

How can I get that?
I have used ''get waveform subset.vi'' but it only takes the first range(0-20ms).

 

N.B. I already have the total waveform data, I just need to get data in range & save it.

Thanks.

 

 

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Help in controlling speed for 4-pin DC fan

February 8, 2018, 7:17 pm
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Hi everyone,

 

I would like to seek help in controlling the speed of a 4-pin DC ventilation fan. Currently, I am using an n-channel MOSFET (IRF520) to switch on the fan whenever the switch is in the ON state. This portion works successfully, but however, the fan speed is not at its full potential. I was intending to use PWM to adjust the speed of the fan but however, I am unable to do so. My front panel, block diagrams and wiring connections are as shown below.

 

My wiring connections. There is also an additional connection from the PWM wire of the fan to digital pin 9My wiring connections. There is also an additional connection from the PWM wire of the fan to digital pin 9Ventilation_Fand.pngVentilation_Fanp.png

Any advice will be a great help, thanks!

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Intel 8 bit Checksum

February 8, 2018, 7:56 pm
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Vision Builder 2015

February 8, 2018, 8:46 pm
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hello,

 

I am using vision builder Al (2015). I am using USB vision camera where i don't find any hardware or software trigger option. So please can anyone tell me how to trigger in vision builder.

 

 

Mohsin

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Tree control selection

February 8, 2018, 10:42 pm
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OK, so this should be somewhat straightforward, but I am unable to find how to do this.  I want to fire an event when I select an element in a tree control and then determine which element was selected.  Right now I can use the double-click function in the invoke node associated with the tree control, but there seems to be no way to determine what row currently has focus.  Thoughts?

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Remove FP boarder when Modal Selected.

February 8, 2018, 11:40 pm
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I'm trying to make a VI where Front Panel Controls and Indicators should be visible but background must be transparent. 

I tried attached VI, Its working when I m selecting Windows Behavior as "Floating" but When I tried Windows behavior as "Modal", its showing a white border. I want to eliminate border when "Modal" is selected. Is there any solution? 

 

 2018-02-08_1905.png2018-02-08_1852.png2018-02-08_1854.png2018-02-08_1854_001.png2018-02-08_1855.png

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Using Multiple Timed Sequences with offsets

February 8, 2018, 11:53 pm
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Hi All,

 

I am trying to implement a series of timed sequences with an offset for each of them. I have attached the labview file for reference. Each sequence is to control a specific vibration motor (turn it on and turn it off). They use a non-re-entrant sub-vi to either turn a specific motor on or off. Each successive vibrator has an offset of starting to the previous one, but it will normally start before the previous one finishes (have some overlap time where more than one is vibrating. When call this sub-vi (without the while loop that is currently surround it) the first time it works well, but each successive time I call it the offsets do not correctly work. Likewise if I run It in a loop (like it is currently set up) it will work the first time correctly but not each successive time. I have  tried playing with the timer source to reset each time but that makes no difference. Is anyone able to help me as to why this would be happening and/or an alternative way to program this? Ideally I would like it as a sub-vi

 

Regards,

Ben

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Using Matlab Code in Labview

February 9, 2018, 12:38 am
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Hi,

I want to use the Matlab Code that is performing an Image Processing task in Labview. I have read this page http://www.ni.com/labview/mathscript/ But i still have an issue that the code has too many function (not build in functions) files that were written in Matlab separately to reduce the code. Now if i have to add all the code into the MathScript it will make the code too lengthy. Here is the list of functions present so you can understand the situation.

I Matlab functions.png 

Kindly guide me how to run the matlab code in Labview while keeping the function simple as possible.

Thanks

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Datalogging Frequency Reduced by Windows Events

February 9, 2018, 1:10 am
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Hi All,

 

I'm using LabVIEW to test communications with various instruments that my company uses. The program is designed to log one data point each second and write it to a text file. I have performed some overnight tests and found that occasionally the period between data points increases to a constant value (between two and five seconds), remains constant at that value for around an hour and then drops back down to one second. This can happen at any time of night and several times per night when I leave the computer running.

 

I think the delayed readings might be due to background processes running on Windows such as scheduled tasks. I've had a look at Windows event logger and plenty of tasks occurred overnight but I can't seem to find any that correspond to the times at which the datalogging slows down. 

 

I was wondering whether anyone has had experience with Windows processes slowing down their programs. Could you suggest which processes might be causing it and what I could do to stop it happening? Any help would be greatly appreciated.

 

Kind Regards,

Dan

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Boolean Button Sticks while running in 2 computers

February 9, 2018, 1:26 am
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hi

the Boolean network shared variables are hoisted on CRIO.

Its connected to Boolean Switch (Switch until released) in GUI through front panel binding.

the same GUI runs on 2 computers simultaneously.

in some instances the Boolean switch sticks and not getting reset.

to reset the switch either the controller has to be rebooted or the value has to be set False  through NI distributed system manger.

 

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How to control the parameters of dynamic vi within the main program

February 9, 2018, 1:56 am
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Hello,

 

I have a main program which controls the CCD camera for a spectrometer. Now I use the dynamic vi which controls the monochromator(Mono) within the main program to move the mono to the appropriate position.  When I start the main program , the dynamic Vi moves to the corresponding position and then main program starts. My question would be that there is any way to control the parameters of the dynamic Vi within the main program which are steps to move  and current position of the Mono as shown below.  I want to these two parameters of the dynamic Vi show up in the main Program.

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IC-3173 FPGA Particle Analysis data transfer to Host

February 9, 2018, 2:40 am
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Hello,

 

I using Industrial Controller IC-3173. I have problems with transfer data of Particle Analysis back to Host machine. At first I grab the image, then I send image to FPGA. FPGA processing the picture and at the end do Particle Analysis. FPGA then send processing image back to host machine. I like to transfer Particle Analysis data back to host, but I don’t know how to do this. I have try with Front Panel Controls and Indicators but this did not work.

 

Front panel communication:

http://zone.ni.com/reference/en-XX/help/371599M-01/lvfpgaconcepts/pfi_data_transfer/

 

Maybe I must assembly the data of Particle Analysis before I send data back to host?

 

Unfortunately, I do not have much experience with LabView. If anyone knows how to do this, please let me know. Thank you!

 

Whole process:

  1. Generate the LabView code vith Vision Assistant.

Ass.jpg

 

  1. Host machine program

Host.jpg

 

  1. FPGA program

FPGA.jpgBest regards!

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Serial Communication through USB testing

February 9, 2018, 8:51 am
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Hello,

 

I'm new in labview programming, I have to create a test case for a micro-controller according to a validation plan. My problem is that I have a subvi having inputs and outputs which are filtered according to their index value. Now I have to create a separate VI for test case which will use the function of subvi but how should I use the inputs and outputs of subvi in separate VI.

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Z scan

February 9, 2018, 4:02 am
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Hi , I'm fairly new to labview. I'm building a z scan spectrometer using a linear stage from thorlabs operating using kinesis software. I'm using a NI Daq 6000 to acquire a voltage reading from 3 detectors.I basically have the program written I just need to find a way of linking the 2 operations together (stage movement and data acquisition). I want the NI Daq to take a reading and save it and then for the stage to step , take reading and so on. Any advice would be greatly appreciated. I have attached screenshots of the block diagram I have so far. 

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Reset Indicator and abort labview program

February 9, 2018, 5:32 am
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Hello

I currently have labview taking a picture at specific time intervals.

How do i reset the millisecond timer value each time the program is ran to zero. Also how do i abort the program when the number of photos=photo number

 

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HTTP GET

February 9, 2018, 5:59 am
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Dear LabView users.

 

I am trying to control a customer equipment remotely using LabView.

I was able to check the functionality using putty. it's on Ethernet, address 192.168.168.1 port 80, RAW.

In the print screen under is a simple function to report the temperature - it works..

 

putty.jpg

 

I would like to perform same task in LabView, if possible using TCP functions, other basic LabView options from "data communication" or "connectivity" panel.

 

I already googled "LabView HTTP GET example" and tried anything that poped out - nothing worked...

 

Please Help

Andrei

 

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3D Plot (Waterfall) in dynamically loaded VIs results in reference leak

February 9, 2018, 6:47 am
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Hi,

 

I'm using a 3D Watefall in a dynamically loaded VI (a dialog showing the 3D Waterfall). The VI is loaded using the "Start Asynchronous Call.vi". It all work fine. I can open multiple dialogs with the 3D Watefall and close them. (see the screen 3d_ref_leak_01.png). This is the only part of the code that touches the 3D plot.

However, when I close the dialog (the subVI with the 3D Waterfall in it), the LabVIEW Desktop Execution Trace Toolikt returns 85 reference leak messages. (see attached screens). Is it really a reference leak? Am I loosing memory?


Using LabVIEW 2017 32 bit on Windows 10.

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Labview 2017 VI not compatible with Labview 2015 system. Any work around?

February 9, 2018, 7:51 am
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So I created a VI in Labview 2017 and saved it under that system. Then I tried to open it in Labview 2015 but it gave me an error:

 

File version is later than the current Labview version.

 

An error occurred loading VI. Labview load error code 9: VI version (17.0) is newer than Labview version (15.0)

 

Is than any working arounds or upgrades regarding this issue?

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