As of right now I am just trying to take a resistance measurement (2 wire) and have it display on my Front Panel.
Anything helps,
myannell
p.s. when I leave the 'write buffer' string blank the VI runs without error
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Serial Commands Keithley 2700
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How to View Word 2013 Document in ActiveX Object
I know that the old method of viewing Word docs was to use a webbrowser object. This doesn't work now since the document opens in word instead. MS has a workaround, but suggests not to use it for new projects(it involves changing the registry and I'llbe distributing this app to other machines so this isn't an option). I'd like to know if why webbrowser2 doesn't show up as a usuable ActiveX object in LabVIEW 2012 and if anyone knows how to use the Word document object so you can scroll and navigate a word document.
Thanks
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RT timing problem after using counter pulse train
We have a fairly complex application running on a PXI-RT8108 (Phar Lap Labview 2011) at 400 Hz without problem. We are now trying to upgrade the whole system to run at 600 Hz. The main loop is using a "Wait until multiple" to get the 600 Hz. The application consists in several triggers using several counters from two NI-6602 that are all timed from a single digital output that is software generated from the main loop. Timing is excellent until another counter is used to simulate the main loop. We use "DAQmx connect terminal" to replace the software trigger by a counter generating a continous pulse train at various rates up to 600 Hz. This is done so that we can simulateo the normal operations to do maintenance on the individual components of the system.
When we run the application at 600 Hz after rebooting the RT system, the timing is excellent. After we run the simulation with the counter pulse train at low rep rate (like 20 Hz), the main application will still run fine at 600 Hz. However, after we run the simulaton mode with the counter pulse train at 600 Hz, the main application will run erratically around 600 Hz. The average repetition rate is around 560 Hz but instanteneous rate varies between 500 and 600 Hz. How is it possible that the use of a counter generating a pulse train can affect the timing of a RT application after the counter is not used anymore? Does the counter use a thread on one of the C
PU?
I have a corollary question: is there a tutorial or an actual manual that explains how to interpret the data from the RT trace toolkit? I recorded the Trace data in the various cases in the hope to understand what's going on but there is no way to interpret the data without more explanation than the poor manual (dating from 2007) provided with the toolkit.
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Update combobox from cluster array
I am looking to update a combo box from a cluster array. The array is indexed then unbundled by name and the element I want for the combo box is selected. How would i update the combo box from here or is this method even the right method of doing it?
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consumer producer event control button top VI
I am trying to control the main.vi example that create the “create project wizard” called “Continuous Measurement and logging” from a top lever VI.
The problem I have is that, I will not start the main.vi unless it’s done by an event created by an operator. How can I control programmatically those buttons from another VI?
I am attaching the block diagram picture from the wizard and the simple top_level VI to control that VI. Thanks
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AO Update channels.vi
Can Anybody explain me briefly what is the use or Functionality of AO Update Chnnels.vi in Traditional NI-DAQ, i'm trying to actually transit my code from NI-DAQ to NI-DAQmx.
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Convert 2D array to 1D array of cluster of 2 elements
Hi,
I'd like to convert a 2D array to 1D array of cluster of 2 elements and I don't know how to do it.
I use IMAQ ImageToArray to have a 2D array like that :
0 0 0 255 255 0 0 0
0 255 0 0 0 0 255 0
255 0 0 0 0 0 0 255
0 255 0 0 0 0 255 0
0 0 0 255 255 0 0 0
and now I'd like to use IMAQ Fit Circle 2 but it needs "1D array of cluster of 2 elements" in input. More specifically, it needs an array of point coordinate cluster (with minimum 3 points coordinate cluster).
See my diagram attached.
Thanks a lot
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Flush shared variables
Hi all,
In my rt application I have a separate task that is responsible for saving the data an displaying the latest values to the user. As I want to see only the latest ones, I do not care about the losses in that case - I use network published shared variables, which have the buffering disabled and rt fifo disabled as well. However it seems that the shared variables are buffered anyway - even though I stop the acquisition (I am sure it is stopped and there is no data being sent to the npsvs) it still takes a while before the host part notices that, becasue there are lots of data being displayed. I check if there are new values with timeout put to 0. I tried using Flush vi, but it didn't do the job. Do you have any idea how to discard all those values that seem buffered?
Thanks for any suggestions
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time-variable input
Hey,
i'm a student in a lab and we have a DC power supply "Agilent E3646A". I have install driver for this. From front panel i can change the voltage but what i need is to simulate the power from a Satellite Photovoltaic Panel.
So, i need to have as input an array with different value of voltage which change every one minute.
Im new in labview and i don't know it well.
I have attached the VI of our supply.
Thank you in advance.!
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Labview Application missing SubVI's, totally stumped
Hello. I am working on a VI that is a simple thermocouple datalogger. I have created it in Labview 2013 (latest patch) on a Windows 7 Machine. It works correctly on the development machine with Labview installed. It uses custom drivers for an Advantech USB 4718 data acqusition module. These drivers were downloaded directly from the manufacturer.
When I build an application and copy it over to a different machine (running windows 8) I get a laundry list of missing SubVIs when I try to run it (see image). This is despite installing all relevant data aquisition drivers (I have verified that the module works with the manufacturers own daq software) the latest version of Labview 2013 run time engine, DAQmx, etc.... I can't think of anything else that should be installed but Im totally stumped.
Anything else I can try? Is it because the Dev machine is windows 7 but the application machine is windows 8? I'm new to building applications from labview, so I'm not sure what I may be missing. Thank you.
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Detect empty element in cluster
Hi,
I want to know if there is a way to detect empty elements on a cluster, with no dependencies on the type/format of the cluster.
I have tried to construct a function with a cluster reference input, use property node "Controls[]" and then check the value in every element in a for loop. But in this approach, if i alter the cluster format, i have to change the reference input.
Is it possible to do detect empty elements in different way that could apply to all clusters without changes?
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TDMS Data storage problem
I want to use TDMS file formats to store data from the DAQ. There are dozens of data every 10 ms, at the same time write to TDMS file. I want to ask to do so will be bad for the hard disk?
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power spectrum output to array
Hello,
I have a signal and i need to make the power spectrum. How can i separate the information in the output cluster of the power spectrum? I have tried to use the unbundle but it gives me an error: " the type of the source is 1D array of cluster of 3 elements. The type of the sink is cluster of 0 elements " If i click on the unbundle it does not let me select anything, it says empty... Does anyone have an idea how to solve this, please?
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Producer Consumer Data Acquisition
Hello everyone,
Over the past few days I've been hammering out what I think is a pretty nifty little program. I'm attempting to log data from an analog input channel at resolutions of around 1 ms using NI's USB 6009. Since the 6009 does not support hardware timing I've opted for producer/consumer daq and write loops respectively. This has worked wonderfully, allowing me to achieve far better resolutions that I might have otherwise. However, I find myself suspicious of the sampling resolution. Are these timestamps simply manufactured along with the acquired waveform, or is data queueing really that powerful? I guess what I'm wondering is how well does the data I'm collecting represent real-time readings.
Thanks,
Travis
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acquisition FPGA
hello !
i've got some problems to understand how to acquire a signal properly, i've got a FPGA 7951R and a module NI5731. I generate a 500 Khz sinewave with a fonction waveform generator, and i plug it into the Analogic input 0 of my module 5731. And i would like to see it into a graph on my FPGA ( see picture attached). i understand that the numbers on the Y axe is the number of samples i got, but still don't understand how to manage the timing loop and the number of sample of my graph ( Y axe ) to get the proper waveform at 500 Khz.
Any help ? thx 
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Unable to detect USB drives.
When this will be fix?
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Area under each peak
Hello ,
I am acquiring a train of voltage signals from NI 9225 module placed on a cRIO 9022 controller ( the frequency changes dynamically )
our main aim is to calculate the area of each peak of voltage curve
and have a floating average of the area.
this was partially achieved 
by using a Trigger and gate VI to detect the sample and then integrate it then store it in a array
The problem is the trigger is activated only for the first peak from the original signal hence irrespective of the frequency the value inserted into the array is constant
Is there a possiblity to get the area under each peak ? and update within one second as the waveform gets updated every 1 second.
I tried to use shift registers and loop back the data but i will be calculating the area of the first peak again and again.
below attached is the modified version of the VI, in LV 2013 , and also the image of block diagram.
I request for your sugestions. kindly let me know if i am missing any data.
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Difference between the Matlab and LabVIEW Hann (Hanning) functions
Hi All,
I'm hoping someone out there can satisfy my curiosity. I have been porting over some code from Matlab to LabVIEW and came accross a difference in the two implementations of the Hann function. Essentially:
LabVIEW has array length = n
http://zone.ni.com/reference/en-XX/help/371361J-01/lvanls/hanning_window/
Matlab has array length -1 = N.
http://www.mathworks.co.uk/help/signal/ref/hann.html
(where n= N in the two implementations)
As I'm not very clued up on signal processing I was hoping someone could explain why there is a difference in implementation and why array length was chosen for the LabVIEW implementation. According to wolfram the parameter a is full width at half maximum:
http://mathworld.wolfram.com/HanningFunction.html
http://mathworld.wolfram.com/FullWidthatHalfMaximum.html
Is the difference just due to the interpretation of what this value should be?
I've attached a modified version of the window comparison example to illustrate the diference.
Thanks,
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Phantom NI 6008
Strange new work setup.
When I log into the T Series Thinkpad running Win7x64 NI device monitor detects a non-existant NI USB 6008 and offers me a blank screen of choices of what to do with it (None of the usual selections like Configure in MAX, Signal express, LabVIEW etc..the selection area is BLANK)
Something tickles the back of my mind that this has been seen before but My Google skills must be a bit rusty. Any ideas anyone?
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Convert String to Decimal for Zigbee on NCD board
Hello,
A short glimpse of what I am trying to do:
I have a zigbee radio hooked up to an NCD AD1216 board. I also have another zigbee hooked up as a serial in my computer. I need to send a Decimal format write command to the remote zigbee and have it deliver back the same format data.
Problem:I can only seem to send text data. I always get hooked up with errors in the Visa read portion of the code. I am trying "Typecast" but there are still errors. I need to send for example "254 33" and it should reply with "85" instead I believe it is sending in either ascii or hex format.
Thank you very much in advance!
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