Moved to Spanish board like where you have posted your past messages.
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Duda selector en máquina de estados
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conversion from labview 2017 to labview8.2
Moved to Conversion board
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DAQmx Counter Output Clear Task.vi doesn't stop the output pulse train
Hi all,
I'm working with a counter output task with a PXIe card and I am noticing that when i call clear task, the output pulse train doesn't stop outputting. I would like to do this in my 'close.vi' wrapper which handles the task generically at this point, and adding a 'daqmx write' call to that vi requires me to know exactly the type for the polymorphic selector.
Is there any way to reset this generically so it would work for any counter out task type, digital out etc.?
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LabView Base Edition and DAQ Analog Output
Can the Base Edition of LabView 2019 drive the analog output of an NI USB-6001 DAQ device ?
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Elevator program
Hello, I created an elevator program and I would really like some help with it. I would that the boolean buttons outside every floor could turn off over a certain period of time, like in a real elevator. Right now they function well, but they remain on.
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Systematic and best way to update database
Hi all
I am having a confusion regarding how to update a database with reference to system performance and overal efficiency.
Actual Situation:
There is a Testplace which performs a number of tests and logs the results to a tab seperated text file. e.g Teststep 1 give result Voltage = 15V ,Teststep 21 give result Current = 2A and so on.( around 10 teststeps) and overall there are 5 Testplaces with each having a different name.
I am now planning to insert the measured values from all testequipments to a database using database toolkit.
Option 1: to use hardcoded queries to insert values to DB. eg. INSERT INTO Testplace1 (Voltage,Current) Values (15,2).
i.e to get measured values from teststeps and to concatenate them to query statements and run it.
The problem with this is: if some columns have to be deleted/inserted in the future, then i have to change every where in the program where it is hardcoded.
Is there a better way to insert values into DB rather than hardcoded queries?
Thanks in advance
Nghtcrwlr
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Controlling separate VI's from one main VI
So I have been tasked to build this measurement setup (Kretshmann setup) which consists of two motorized rotation stages, spectrometer and a CCD. Since I'm new to LabVIEW the task seems pretty overwhelming, and I would really use some help. I already have separate VI's for each component and the idea is to make a single main VI which will control these. The main VI will have a loop of some kind which should call the subVI's when they are needed. Programming the mainVI or the logic behind when to call the subVI's is not a problem. The problem is that I don't know how to modify the VI's such that they can be used as a subVI in the main program. I dont know if this is even possible since they are designed to be standalone programs. Any suggestions? The VI's that I plan to use are listed below in attachments
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Vivado CIC broken LV 2018 and 2019
I'm trying to port some code to a Kintex 7 target. One of those code pieces is a CIC filter (Xilinx IPCore).
I can't get the darned thing to work. It will only present me with m_axis_data_tdata ports of 32bit width, irrespective of what is set in the dialog. Here's an image of a LV2015 node vs 2018 / 2019 node. What on earth am I doing wrong?
Both nodes were configured identically, 4-channel decimating filter (4-fold decimation), frequencies of 40MHz and 160MHz, 20 bit input width, full precision, 28 bit Output width, Latency 19.
Help?
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MCC DAQs stop reading input analog voltage when VI is running
SETUP:
I have a set of twelve thermistor circuits with an input voltage of 5V who's voltages are being read through three different DAQs. One of the DAQs is an NI USB-6008 which encounters no issues. The other two are a Measurement Computing USB-1208FS and a USB-201. I have written a VI which sets up all the DAQs to read analog voltage and uses the Steinhart- Hart equation to convert that voltage to a temperature. Since I am not interested in quick variations of temperature and to increase the resolution of my temperature readings I store one temperature reading every second for 1000 seconds and then average them. That average temperature every 1000 seconds is then written to a file.
PROBLEM:
The problem I am having is that the two MCC DAQs will occasionally act as if they are reading 0 volts which corresponds to a temperature reading of roughly -450 F. They will continue to read this temperature until I restart the VI. This problem occurs independently for each DAQ so even if it is happening with one it is not necessarily happening with the other. I believe I have set up the DAQs correctly based on ULx examples on reading input analog voltages. I have tried my VI with and without the ULx Start VI since I've read it may not be necessary depending on the application and the problem persists in both cases. The VI I have attached includes all of the thermistors but I have also written VIs that only use one DAQ at a time and the same problem occurs.
FILES:
I have attached a set of VIs that show what I have written for one of the MCC DAQ systems. The main file is what sets up the DAQ and performs the readout, averaging, and recording of the data. The sub-VIs handle the temperature calculation for each thermistor on the particular DAQ separately. There is no difference between the VIs for this MCC DAQ system and the other so any issue found on this VI will correspond to the same problem on the other.
Please note, the system I am working an is older, refurbished system which runs LabView 2009 SP1 so if you need a more up to date version just let me know and I will upload that. If there is any more information you need let me know.
Thank you
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timing plot with loops
Hello community
I am a beginner with labview ,I am writing a VI using a while loop to measure current in time and plot it using a graph. the time axis shows the number of iterations and not the time.
is it possible to plot the current with time and not with the number of iterations of the while loop in the graph?
how many iteration while loop executes per second ?
the same questions for For loop!
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Synchronised finite duration analog input and output DAQ in nested for loops too slow
Hi all - first time posting here so I hope I'm following the protocol.
What I want to do: capture the acoustic pressure distributed an area by using LabVIEW to repeatedly: 1. move a robot arm into position then, 2. transmit a number of sinusoidal signals at different frequencies and, 3. capture the transmitted signal with a microphone (attached to the robot arm).
A material will be placed between the transducer and the microphone and the result of the test will be the effect of the material on the pressure field spatial distribution as a function of frequency.
What I have: I have two nested for-loops: the outer loop indexes through an array of positional coordinates to control the robot arm while the inner loop indexes through an array of waveforms. Data capture is triggered by the onset of the transmission and both the read and write VIs are set to "Finite sample" mode. The attached VI is a simplified version.
In the complete version a column array is saved to disk in a binary file in the format:
["Position 1 index", "Signal 1 index", "Signal 1", ..., "Signal N index", "Signal N", ..., "Position N index", "Signal 1 index", "Signal 1", ..., "Signal N index", "Signal N"]
The problem: For typical values - number of positions (measNo) = 14641; number of transmitted signals (wavesNo) = 41; sample rate = 100-200 kHz and #s = ~400 - this is taking me ~8 hours despite being <20 minutes of transmission time in total.
I'm sure it's because of the many, many task creations and destructions but I haven't a clue how to proceed.
Can you help me speed things up?
Few things to note:
1. The DAQ in question is USB 6251 with LabVIEW 2018.
2. No data is being saved in my attached version - this isn't the issue and I can write about 1.5 GB of data to disc in <10 s in binary format.
3. Control of the robot isn't the issue either - the robot arm can move to (121 x 121 =) 14641 points in <30 minutes.
4. I've searched the forum and looked at the white papers but I am very new to LabVIEW and any similar solutions I've come across are above my head at the moment. Patience is appreciated here!
Thanks!
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USB 2009 2 channel daq mx osciloscope
Hello,
I have an issue with a osciloscope project.
Does someone have a more easy example to help me?
I already have some from other websites like "studentscope" "labviewscope" etc.
I realy could use a more simple one. But with daq mx tools. No DAq assistant.
Thank you
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Registration in excel
Hello I would like to save data in an excel file but the vi me generates an error how can I do ..?
Thank you
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PXI 1082 and labview real time module
HI,
I'm new to PXI 1082 hardware, does PXI hardware have to build by using labview real time module?
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Conditional System Exec with Initialization
Hi, I'm trying to create a button utilizing the System Exec command; I've created a batch file for initialization and two for start and stop the UV box using a boolean button, but keep getting the No Listener on the GPIB/Memory is Full error. Could anyone help me with this problem/check if my block is per common practice?
TIA!
![VBswUGz[1].png](http://ni.i.lithium.com/t5/image/serverpage/image-id/248907i42F421538D2E4BDA/image-size/large?v=1.0&px=999 "VBswUGz[1].png")
Mike Nguyen
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Installing an application built in Labview
I have built an application in Labview that runs fine on the machine on which it was created. When i install this on another machine the app does not seem to communicate with the cDaq or its modules that are attached. I can see the devices in the device manager, and all are there, however when running the app there seems to be no link to them as the active light on the cDaq never comes on as it did on the other machine. were there files I forgot to add previous to the build of the installer.
This is the first time i have tried to install an app on another machine, and am fairly new to this.
thanks for any help
PK
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Basic Averaged DC-RMS for N Chan
I need to use the Basic Average DC-RMS for N Chan to process my signal. However I have the base version of labview and this function is not available. I am looking for an option of a subVI to do the same but using functions available in base version of Labview.
Any help would be highly appreciated.
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implementation of GMSK modulation in Labview
I am new in labview. I want to Implement GMSK Transceiver in labview .kindly suggest how can i implement Gaussian MSK. kindly suggest any document or VI. your help in this regard is highly appreciated. thanks in Advance.
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E2V Camera SDK DLL, cluster configuration with the Moveblock function.
I'm working with an E2V camera SDK that provides a dll written in C. I have nearly all functions working with the exception of one, the most important one that retrieves the image data. The function provides a pointer to a structure which I can get and send to the Moveblock function. I'm able to retrieve some of the data but I'm obviously doing something wrong.
I have a pointer to a structure called tImageInfos. How would I use the LabVIEW Moveblock function to extract the data from this structure? I'm using 64-bit LabVIEW and I understand that size_t variables
are unsigned 64-bit integers. I'm not sure about the datatype to use for hBuffer Handle and pDatas pointer. I'm really trying to get the array data from the pDatas pointer but so far, most of the data I'm extracting doesn't make sense, although some data points do. It seems the data doesn't seem to be ordered the way its defined below. Any help would be appreciated. The struct is defined below:
typedef struct
{
/*! Buffer handle which contains new data. */
BUFF_HANDLE hBuffer;
/* Pointer to the beginning of the image datas (including contextual datas if they are enabled) */
void * pDatas;
size_t iBufferSize;
size_t iImageSize;
size_t iOffsetX;
size_t iImageWidth;
size_t iImageHeight;
tImagePixelType eImagePixelType;
size_t iLinePitch;
unsigned short iHorizontalFlip;
unsigned long long iNbMissedTriggers;
unsigned long long iNbLineLost;
unsigned long long iNbImageAcquired;
} tImageInfos;
Thank you.
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Labviewでファンを作動させるプログラムについて
labviewでファンを回すプログラムを作っているのですがファンが全く作動しません．ファンのモータはパルス幅変調で動かしていて，パルス幅の入力を0.00045(s)，パルス幅周波数が8000(Hz)として，デューティー比を約0.4として出力しています．そのプログラムも添付します．マイコンはmyrioを用いており，myrioからスピコンに端子をつないでいます．その画像も添付します．スピコンのパルス幅周波数は8000(Hz)です．
I make a program to rotate a fan with labview, but the fan doesn't move at all. The motor of the fan
moves by pulse width modulation. I assume the input of pulse width is 0.00045(s), the pulse width
frequency is 8000(Hz). And the output by duty cycle is about 0.4. I attach the program in labview.
I use myrio as a microcomputer and connect the terminal from myrio to a speakon connector.
I also attach the image. The pulse frequency of the speakon connector is 8000(Hz).
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