Hi,
I'm trying to make USRP transmit some signals at every time the rising edge of octoclock's PPS signal is found. How to do this? Is it enough just by using niUSRP set time.vi and niUSRP configure trigger.vi?
Thank you.
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synchronizing USRP and octoclock
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TFS CI, Build Automation for LabVIEW projects?
Long story short, is there any way to build automatically Build Specifications on a remote Team Foundation Server for LabVIEW projects... or everything has to be comitted / pushed / checked-in with the latest build specifications binaries?
I think the answer is no, but still would like to double confirm that with the experts who already gave a try with standard build automation systems.
Thanks,
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voltage read from arduino convert to frequency in labview
hello.. i am working on a project where i have to detect pulse from wrist. i am using pulse sensor that i have interfaced to arduino. i am using labview to read the analog voltage.
how can i measure the frequency of a pulse from analog voltage? please help me out asap
along with this post i am enclosing my vi...
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Multiple step responses on the same plot - control and simulation
Hello,
I am using CD Step Response VI to simulate the step response of simple control loops and then viewing it on a step response graph.
Now I have two seperate control loops (transfer function) and would like to view the step responses of both loops on the same plot/graph.
I tried using "merge signal" and "bundle" but I am not able to wire it to the step response graph.
Kindly request suggestions as to how I can solve this.
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maximum length of tdms file
Hi Wonder if I could be advised, really cant be learning the hard way again!
If we log at 500kS/s into TDMS file, Is there a length/size after which data is not added into TDMS columns anymore? Or it continues logging till windows throws message that system is running out of memory?
Many Thanks
K Waris
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Amount of money to bills and coins
Hello
I am creating a vi of a vending machine and I got to the point where I have to return the change.
I want to display the change in 1$ dollar bills, quarters, dimes, and nickels but I have no idea how.
I have already done that in another programming language where I substracted the integer from the double (ex assuming amount =2.45 ---> double(2.45)-int(2.45)=2.45-2=0.45) so int(2.45) which is 2 goes into the 1$ bills and the rest which is 0.45 into the rest and so on.
In LabView however it seems that int(2.45) is = 3 not 2 so I cant use that method.
How can I proceed?
(the following should be done when both case structures are false)
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LabVIEW crashes 0xAC17A51A in transact.cpp
Hi everyone,
I have following issue:
A project, with VI, that sets DC output voltage in DAQ card. When I run the file within the project, it returns error, "cannot create DAQ channel"
There is no possibility to select any channel on any devie device. When I open diagram panel, and create a channel constant, LV crashes with "Error 0xAC17A51A in transact.cpp".
In MAX device working properly, also it does, when I create a fresh file with DAQ functions, or run this VI in standalone mode.
What could be a reason for that?
Thanks,
Dirs.
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Xy Graph x,y value programmatically change
Hi,
i am using labview 8.2.want set x,y value programattically.for example i will give x min value 6(clock) and max 10(clock),interval 30min.so 6:00,630,7:00,7:30.....up to 10:00 how to set this type.i tryed using property node min and max property but this not give correct output
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eventhandler and event call back from .net dll doesn't work.
Hello,
I have a .net dll that was written in C#. This .dll called nalusb.dll is also used in a usb tester program that is also written in C# and I am trying to do something similar in labview which will connect to the device, write data to the device and read the results. In the usb tester program that was written in C#, nalusb.dll calls an event to read the data. There is a public event in nalusb.dll that is called PacketReadCompleted and there is also a public delegate called PacketReadCompletedEventHandler. I am able to connect to the device and write data to the device but after I register the callback event to PacketReadCompleted, the read event doesn't get handled after data is written to the device. Do I need to do something with the PacketReadCompletedEventHandler? This is a delegate which requires two inputs of type object and method but I have no idea what to wire into those........ I've included a snippit of the C# code of the usb tester. I think I am stuck on the line I highlighted in red. I've also included what I have so far in labview. The section in purple is what I would like to do. Any suggestions or help will be greatly appreciated!
public CentralForm()
{
this.InitializeComponent();
this.nalUsb = new NalUsb();
this.nalUsb.PacketReadCompleted += new PacketReadCompletedEventHandler(this.OnNalUsbPacketReadCompleted);
this.nalUsb.ConnectionLost += new EventHandler(this.OnNalUsbConnectionLost);
this.UpdateDevicePresentStatus(NalUsb.DevicePresent());
}
private void OnNalUsbPacketReadCompleted(object sender, PacketReadCompletedEventArgs e)
{
string eventDescription = "Packet Read - ";
if (e.Type == PacketType.Data)
{
eventDescription += e.Data.Length + " Bytes";
this.receivedTextBox.Text += Encoding.GetEncoding(1252).GetString(e.Data);
}
else if (e.Type == PacketType.FlowControlValues)
{
eventDescription += "Flow Control Values";
this.dsrCheckBox.Checked = e.Dsr;
this.ctsCheckBox.Checked = e.Cts;
this.dcdCheckBox.Checked = e.Dcd;
this.riCheckBox.Checked = e.Ring;
}
this.eventsTextBox.AppendText(eventDescription + "\r\n");
}
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TDMS error on example project
Hello, I downloaded LabVIEW 2015 and I'm trying to test an example project called "Continous Measurement and Logging" but every time I try to record the data, I get the following error, -2519, then error -2501 indefinitely:
The other project that uses TDMS files mark the same error, I tried to change the path, use a blank file, running LabVIEW as admin, update the software, but nothing.
I'm using the evaluation version and I have 2010 and 2015 installed. any other info you need feel free to ask. Thank you.
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dynamic call a sub vi from vi.lib in exe program
hello all,
i try to dynamic call a sub vi which include a function vi from VI.lib (emaple MEAN.vi) in a exe main program, it is can run on edit mode, but once I build main program to exe file, the sub vi can not run.
can somebody try it?
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How to connet Datahog2 (Skye) to LabVIEW?
Hi all,
I would like to know how to collect data from data logger?
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Communicate with PSoC. What should my connection between LabVIEW and PSoC be?
Hello,
I'm currently set to work on are project where the basic is that 3 LEDs are blinking with a PWM. The LabVIEW code are handed over to me and now I have to adjust from generating the PWM signal form LabVIEW to controlling the LEDs from PSoC-4 with an LED driver TLC59711. I'm not familiar with PSoC and I'm supposed to get my PSoC-kit and the driver later to day. I do not have any clue of how I should connecting the PSoC code + driver to my LabVIEW. Should I use the NI-VISA, and how does this work. I'm sorry for the lack of detailed information but I'm still not sure what I should do, but hopefully it will come to my along the way. But let me now if you need other information and I'll try to collect them.
Could anyone give me some start advice?
The code I think I need to replace is digital part in the upper left corner of my snippet.
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Where does the FPGA DMA FIFO locate?
Hello, I need the information about DMA on sbRIO board.
We use sbRIO 9606 and the board can communicate with host PC and FPGA target via DMA.
Just my colleague is curious that where the DMA's memory locates. Does the memory locate on FPGA chip?
I mean, the Xilinx chip has memory area (FIFO area) for DMA transfer? Or peripheral circuit is existed?
From the knowledgebase; http://digital.ni.com/public.nsf/allkb/0A008919E1551B1A86257B9D00764FC4
sbRIO has 5 DMA channels.
The LV help has a diagram but it does not answer my colleague's question.
http://zone.ni.com/reference/en-XX/help/371599L-01/lvfpgaconcepts/fpga_dma_how_it_works/
I checked Xilinx website also, but I couldn't reach the answer.
sparten-6 LX FPGA has 5 memory interface controller blocks and I am guessing that are DMA transfer memory. Is it correct?
Even though, I can not reach the answer for physical location on FPGA board. The top diagram on page 4 of the following looks good but not answer for my question;
http://xilinx.com/publications/prod_mktg/Spartan6_Product_Brief.pdf
We look forward to get the reply for this issue.
Regards,
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regular expression (*, +)
Hi,
I have a simple but complicated question on regular expression using star(*) and (+).
When I wanted to detect a floating number, I used [-+]?[0-9]+\.?[0-9]+ but found [-+]?[0-9]*\.?[0-9]+ is more popular in expert people.
In this expression, * was used in the decimal part but + used in the floating part.
In definition, * can exclude a character itself but + need to get the number definitely.
Can you give me wrong example for "[-+]?[0-9]+\.?[0-9]+" which can detect a number rightly by "[-+]?[0-9]*\.?[0-9]+ " ?
labmaster.
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FPGA+RT Architecture and Design Decisions
Hi guys.
I have a question specifically relating to the sbRIO-9651 that I am working on, but would also be interested in more general answers if all RT and FPGA devices work the same.
My first question relates to the architecture of the hardware. Is the RT and FPGA in parallel or in series? So does the signal go Windows PC -> RT -> FPGA or would it go PC->RT and PC ->FPGA?
My second question is, what is the purpose of having both RT and FPGA, and how do you decide which one you wish to use? If you wish to use both, why is that?
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reading the sample rate of the NI9862
Hello everyone,
I am using a DAQ chassis with modules 9205 (analog input) and 9862 ( NI-XNET CAN).
I have a program to sync the modules for acqustion based off of the example attached. My question is how to determine the rate that the data is coming in from the 9862?
It seems to be twice the rate of the 9205 when I set the sample rate for the 9205 at 500Hz.
Is there a property node or method I can use to find the rate? I looked in the manual, and it does give any information.
Thanks
Griff
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Code Running in Debug Mode, but not in Standard Mode
Hi Everyone,
A few months ago I wrote some code that records the current over time. It measures the current every 1s, and it gives the user the option to specify how often the data should be coded. It can be either linearly (for example, every minute), or logarithmically (small increments in the bigger leading up to a larger value and the user can specify the maximum sample intervals). I also created a queue that will record the "last minutes". For example, if the user wants to see what happened in the last minute, he will have every second recorded and that data will be appended the end of the file.
However, it was a messy piece of code (although working), and I wanted to clean it up so that it would be easier to add to in the future. I started to learn about state machines. I am building it slowly. First the user pushes play, and then fill in where to save, maximum recording intervals, other variables etc. and click load. After, the user can push play to start the program. At the moment, it is not connected to any equipment, just wanted to get the time recording intervals working.
At the moment, if it is run in debug mode, everything runs fine, but if it is not in debug mode, it stops after a few intervals. I think that is most likely a race condition. I do have some local variables, and I read that they should only be used if there are being used in two places within the same VI. But I don't think I am using them in the subVIs.
Can anyone give me some advice please? It looks like it is not updating to the next recording interval. I have attached my code.
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Can someone create a program for me to calclate resistane using current and voltage. I need a visual graph and a few knobs for aesthetic purposes. PLS HELP
Hey could someone create a labview program that uses current and voltage to find resistance. I also need a graph and knobs for aesthetic purposes. PLS HELP A GAL OUT!!!
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Serial communication Motorola Barcode scanner (PL3307)
Hello!
I am trying to communicate with a barcode scanner through a virtual serial COM port (CDC). If I enable the "continuous reading" I can easily read a barcode with a continuous VISA reading loop. However I do not want the scanner to be on continuous reading. I want to use the pull trigger command. I am trying to send this command to the scanner but nothing happens. When I use an example from the developers guide (https://atgsupportcentral.motorolasolutions.com/content/emb/docs/manuals/4045103a.pdf) to request a parameter, also no response.
I attached a print screen of the really simple VI created to request a parameter. 7 bytes are written, but no bytes are received(no response)
Anyone who can help?
Michtro
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