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Accessing both Channels Ag 53220A

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Hello everyone,

 

I am quite new to LabVIEW and facing my first most probably small issue concerning the alternating measurement of frequencies on two (or more) channels of an Agilent 53220A frequency counter.

I am able to measure one channel and display this measurements inside two graphs. However, I can't figure out how to measure both channels.

I know that one can't measure them simultanously, but I'm fine with alternating measurements (like every second one channel).

 

How can I achieve this?
I will attach my block diagramm to this post.

 

Thanks for your help!


Get date time in seconds under the hood

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Hi everybody,

 

I'm working on a test bench with a PCI card Meinberg PTP270PEX.

 

This card is able to overwrite the Windows System time with a Windows service working transparently.

 

Since Windows 8, a new time management has been introduced, allowing to get timestamps with a true µs resolution. So, it's possible to get high resolution time under Window using the "GetSystemTimePreciseAsFileTime" fonction of Windows.

 

My question is : what does exactly the standard "Get date time in seconds" of LabVIEW Under the Hood ?

GetSystemTimePreciseAsFileTime call or a standard GetSystemTime call ?

 

I don't want to do a dll call from labVIEW because of the calling time of the dll which will introduced a time offset on the timestamp.

 

Best regards,

Help Converting Traditional NiDaq Counter VIs to NidaqMX

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I am looking for support on getting the attached VI converted to NiDaq MX. Any help or guidance would be much appreciated.  I have attached VI and all associated with its hierarchy incase it was required.  VI I am looking for help on is named "Read Digital 1/min Raw Data" 

 

Current version is labview 7 moving to LabVIEW 2017

 

Thanks in advance for any help / guidance.

Labview Core 1 2014 version multimedia loading problem

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Hi All,

 

I have labview core 1 2014 version but I am having problem playing the tutorial videos. Once I try to open the videos a browser opens but it will get stuck trying to load the material. Does anyone know how to fix this?

 

Dag

Create an EXE able to read and write the console

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Hello the forum,

i'm trying to code a VI that will be built as an EXE and called by another VI using the System Exec function.

 

The EXE should be able to:

1. read an input string from the console that will be treated as soon as the called EXE starts running

2. write an output string to the console that will be treated as soon as the called EXE ends running

 

Here's the result of my search (in terms of links):

https://forums.ni.com/t5/LabVIEW/how-to-make-a-VI-write-to-standard-output/td-p/347392

https://forums.ni.com/t5/LabVIEW/console-app-from-labview-VI/m-p/77569

https://forums.ni.com/t5/LabVIEW/Standard-output-on-system-exec-VI/td-p/3358128

http://dslweb.nwnexus.com/~ast/dload/guicon.htm

https://docs.microsoft.com/en-us/windows/console/getstdhandle

https://docs.microsoft.com/en-us/windows/console/writeconsole

https://forums.ni.com/t5/Developer-Center-Resources/Passing-and-Receiving-Pointers-with-C-C-DLLs-from-LabVIEW/ta-p/3522714#_Passing_Pointers

https://forums.ni.com/t5/LabVIEW/Calling-subroutines-from-dll/td-p/151367

 

And attached there's a screenshot of what i coded on the diagram of the called EXE. A file is generated with the errors details and the values coming from the Kernel32 funcitons. An error code 1097 appears as the first function is called.

 

Any clues on how to achieve the goal?

Thanks!

 

 

Leading zeros in numeric control

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Hi 

I am pretty new to labview and learning.  I am trying to enter a number 003330 in a numeric control in my vi  But it drops all the leading zeros.  I cannot define this as a string as I will be passing this value from the output of the previous step in the teststand sequence which is Type: Number (dbl).  Thanks for the suggestions.  

How to see LV object parameters in Teststand during debugging

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I am developing a Teststand program in conjunction with a LabVIEW OOP. I create objects(instruments like DMM, SA) in TS, configure and do measurements. I have a requirement to view the Objects' parameters during debugging- for more clarity, consider a step for making a measurement and I place a breakpoint in it. When the control reaches that step and before you step into the VI, I would like to see, maybe  a window pop up where the parameters are displayed. Is this feasible in Teststand? If not, please recommend alternate ideas

802.11 Application Framework: Why doesn't 802.11 FPGA STA.gvi run when the 802.11 Host.gvi runs?

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Hello, I have a fundamental question about the application framework logic that I can't seem to figure out.

 

I have looked at the FPGA Host Interface learning example and it seems that the required blocks for running FPGA code from the host are: Open FPGA VI, Download FPGA VI, Run FPGA VI, Read/Write FPGA VI, and Close FPGA VI. I understand how this example works, and how you can run in either deployed or simulation mode.

 

What's nice about this example is that you can edit the FPGA.gvi file and run the host file in simulation mode, and you don't need to compile the FPGA code (which is time intensive).

 

From what I've seen of the 802.11 Application Framework, all the same blocks are present and the logic (at the simplest level) should be the same. However when you run the 802.11 Host.gvi, the 802.11 FPGA STA.gvi does not run. I don't understand why this gvi doesn't run. Is the only way to implement changes in the FPGA to overwrite the pre-compiled build files?

 

My current objective is to implement a similar "deployed/simulation" option in the 802.11 application framework as the one that exists in the FPGA Host interface example. I'm new to this framework, so if that option already exists somehow please let me know!


Creating a sin wave from a square wave

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I'm working on a project that involves creating synchronization waveforms to be used outside of an NI compact Rio. I can guarantee that my cRIO clock times are synchronized (using TSN/802.1AS in the cRIO 9035s). Based on an example I found, I have labview generating a square wave based on switching the signal every time period N (using the clock as the reference). However, I'm having trouble finding a way to convert this signal into a sin wave. What is the best way to convert my square wave of frequency F into a sin wave of frequency F? 

Issue with Target RAM Ramping Up on sbRIO & myRIO

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Hi,

 

I am running an application on 6 different NI targets for 2-3 months in the form of an endurance test to validate my application on multiple targets over a period of time. Targets are either myRIO 1900 or sbRIO 9637. I have observed that sometimes, all of a sudden the RAM on a target starts to rise up until that target crashes. All of the targets run the same application; therefore, i was wondering if it could be as a result of something happening beyond my application and maybe something happens with Linux RT. My application is a relatively large application including CVT operations, launching subVIs, using TDMS at 10H, etc. The is reason I became suspension about something else beyond my application, is that it only happens to one or two of the targets after I start them all at the same time. It doesn't happen to the same target all the time though. 

 

I was wondering if this has been seen before by anyone? or if anyone would know about possible causes of RAM ramping up suddenly if target has been running for an extended period of time?

 

Thank you,

Pegah

Combo box to initiate event causes program freeze

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Hi All, 

 

I am building an application that allows an operator to specify a corrective action taken to fix a part on the line. The customer has 3 levels of repair specificity in an access database that I am using to populate combo boxes that the operators will select. Code executes like this 

 

Call SQL database to populate vague level 1 options in combobox

Event structure to save vague problem and exit, or wait for value change in combo box  

   which 

Calls level 2 values based on combo box 1 selection,

Event structure to save specific problem and exit, or wait for value change in combo box 2

   which 

Calls the level 3 values based on combo box 2 selection 

Operator saves very specific problem and data is stored. Exit VI. 

 

 

It seems that the program will freeze after making a selection. I can change combobox 1 exactly 1 time, but then it will not allow me to change combobox 2. I cannot select anything in combo box 3. Highlighting execution shows the problem is when waiting for an input into the event structure, but I can't change the values linked to the event.  I know the SQL queries work because looking at the comboboxes after stopping the program shows the correct values. 

 

I appreciate any input. 

LabVIEW doesn't load when installed (and never appears in task manager).

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I am trying to install a LabVIEW 2017 evaluation, however whenever I install the program and run the executable, LabVIEW doesn't run. The executable does absolutely nothing. In the past I have improperly uninstalled another version of LabVIEW (that worked fine), but do to my not using the uninstaller, there may be loose files scattered about my drive and registry that I cannot find. I have used the NI package installer to remove some of the corrupted NI files, however when I run the LabVIEW installer, everything is fine except that "NI Measurement & Automation Explorer 17.0" is still installed locally as shown: untitled.png

 I also cannot choose the remove this feature and this doesn't appear in my NI Package Manager. According to the manager, all relevant NI software has been removed, and yes, I have gone into the settings to display everything, not just products and applications. I have lost alot of time working on a final project for school due to this issue. I would appreciate any ideas anybody has to fix this.

Read word document

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Is there a way to read a word doc and do something if it finds text and do something else if it finds an image?

DAQ Assitant: Setting "signal input range" outside calibration range

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I have a question concerning the calibration and measurement of thermocouples using the DAQ assistant.

 

I want to measure temperatures at cryogenic temperatures (liquid nitrogen, ~-196°C).

 

To calibrate the thermocouples, I used a two point calibration (ice water, 0°C and liquid nitrogen, -196°C).

 

Now I cannot set my "signal input" minimum below -196°C, this causes an issue since now I cannot measure below -196°C. Especially I cannot see the "negative" (below -196°C) noise of the signal when in liquid nitrogen.

I can set the minimum signal input to a lower temperature if I disable the calibration, however than the measurement is highly inaccurate.

 

The error i receive is Error -200077 (which is explained here https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000P7gySAC).

 

Is there an option to let LabVIEW extrapolate the form the calibration range?

 

I couldn't find anything online so I appreciate any help. Thank you in advance for your answers.

 

Using the accelerometer MPU 6050 with the library Makerhub and Arduino.What's the purpuse of clock source and the I2C channel?

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Hello everyone! I'm new using arduino and labview and I try to measure vibrations with the accelerometer MPU 6050 using arduino. I have seen a few of tutorials and read a little all about the topic.

My question is about the library Makerhub from Labview to the accelerometer MPU 6050. I do this program following a tutorial :

hhh.png1._ how you can see, the block of open have a branch whose name is "clock source" that is associated to the constant see it on the screen (Internal 8MHz Osc). This confuse me a little becouse it's seem like if the MPU 6050 is the one that generate the clock pulse. And for what I read about the I2C communications protocol the device that do this is the master, that in this case is the Arduino. And the other hand, it's possible choose other constant values like :

dsfgd.png

Someone can explain me what's mean every possible opción and why I should use the first that is "Internal 8MHz Osc" ?

 

2._ Why the thre blocks : Open, read and close are associated to one branch that is a constant 0, that define the I2C Channel? Why can be needed several Channels? . I mean, this confuse me a little becouse for what I read all the devices that are connected with a i2c bus, only need one channel, becouse all the devices are connected in series like this picture : 

bAILALO.png


Oculus Communication with Labview

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We want to communicate oculus with Labview. But i don't have any idea about How i get input from oculus to labview(PC). Does any third party device require? how labview gets input from oculus?

Activate switch issue

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Hello,

 

I'm using Matrix module in my test setup.

Trying to switch signal_x to 24V using Matrix card c1->r0 and then after certain delay of 1 sec, would like to enable signal_y to 24V (c2->r0). when I perform second signal enabling both signal_x and signal_y should be at 24V.

But I'm facing a issue that the signal_x will be disconnected when I try to switch signal_y.

 

Can some one help, how can I program them so that both signal will be enabled with a delay as explained above.

 

c1=signal_x

c2=signal_y

c3=signal_z

r0=24V

aquired picture gets darker

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Hello,

i've created a labview program with NI Vision.

I acquire a picture with a webcam and then check it if there is a cube and get the position of the cube.

The problem is each time i run the inspection the acquired picture gets darker.

I've got the same problem when i open the inspection with NI Vision.

The cable of the Webcam is about 1.5 meters long and i enlarged it with another 2 meter long cable to an total length of 3.5 meters, earlier i was using a cable with an total length of 4.5 meters with the same problem.

When i use other software(vlc player) to just acquire a picture the picture dont change.

I've attached a picture that shows the problem and the NI Vision inspection that i created.

I'am using this webcam: ELP 1080P 2MP 30fps JPEG 1920 x 1080 Full HD Mini USB Box CMOS Kamera mit 2.8-12mm Vario Objektiv

Uses of NI 6585B external clock

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Hi all, I want to sample the digital data using global clock (external clock) instead of the internal clock in the 6585b data module with the 7965R card. I am using the global clock in SCTL loop for sampling. Please give me the detail whether the sampling happens as per the clock provided to global clock externally with variable frequency range in runtime or it is fixed.

IMAQ AVI for Labview Research License

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Hello, does IMAQ AVI Vi available for Labview Research License? I have LabVIEW 2013, but I cannot find IMAQ AVI VI\i in it. I have installed this from this url (http://www.ni.com/download/ni-vision-acquisition-software-february-2013/3818/en/). I don't think this is it as I still cannot find the IMAQ AVI VI in my Labview. It shows '?' on the VI.

 

If someone know where can I get it, please share it with me. Thank you very much.

 

 

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