Quantcast
Channel: LabVIEW topics
Viewing all 69214 articles
Browse latest View live
↧

VI containing Event Structure will not receive front panel events in LabVIEW Real-Time.

June 4, 2015, 10:23 am
$
0
0

Hi again, I'm working in my first UI (attached VI).

 

It works when running directly from PC. It doesn't when running from cRIO, there's the message "VI containing Event Structure will not receive front panel events in LabVIEW Real-Time". I've been reading and I found that "Event structures on RT targets do not support events associated with user interface objects, such as VI panels or controls. For example, associating the Value Change event with a control does not work. RT targets support only user events".

 

  1. Is that the problem? If it is, how can I create Mouse Up, Mouse Enter, Value Change (or other user interface events) user events?
  2. If I run my VI in FPGA mode should it run?
↧
Search

Save only part of my indexed data

June 4, 2015, 11:22 am
$
0
0

Hi Folks! I'm having some trouble saving only part of my streaming daqmx data to disk. I've attached a gauss meter to a Zaber stepper motor, and have it moving from a home position to an absolute position. at the same time, my gauss meter is mesuring data via daqmx while stepping. when i get to the end of the line, the stepper motor returns to home...data is recorded in both directions (forward and backward). I only want the forward data to collect. reverse data is not needed. this is especially important when i want to run more than one scan (move forward and backward n times.) I have a while loop gathering data (see attached.) Any ideas on how i can only record/index partial data coming in? Thanks in advance!

↧
↧

BSOD 0xD1 on Windows 8.1 when using Asynchronous VISA and USB to Serial Adapter

June 4, 2015, 11:56 am
$
0
0

I was consistently getting a BSOD with the code 0xd1, on usbser.sys, on windows 8.1. I am running LabVIEW 2013 SP1. The bluescreen only occurs on Windows 8.1 and everything functions fine on 7 and XP. 

 

 The "USB to Serial Adapter" is actually a microcontroller, not a physical USB to Serial adapter. The microcontroller's usb driver is just an INF to point to the generic Windows USB to Serial drivers. 

 

The BSOD occurs after several minutes of my software running, while it is polling the controller every second. After changing the communications mode in my software to synchronous on every VISA write and read call, the BSODs stopped occurring and the program has been running stable for several hours now on Windows 8.1.

 

This BSOD seems to be the result of a strange interaction between the hardware, VISA and the Windows 8.1 USB to Serial drivers. Sending lots of traffic through a terminal emulator does not produce a similar BSOD.

 

Has anyone ever seen anything like this? If so did you discover an explanation or any clues to fixing it more permanently than always using synchronous communication?

↧

pleas help me on my SCADA system

June 4, 2015, 12:45 pm
$
0
0

i am trying to develop a SCADA system using LabVIEW. i can read data from the OPC server but when i try to write from LabVIEW to the OPC server an error message will appear. so, what can i do pleas help me.

 
↧

Labview with pressure gauge instrument

June 4, 2015, 2:09 pm
$
0
0

Hi,

 

I've gotten my pressure gaugse instrument setup with NI Max, so I can send and read commands via serial (RS232). However in Labview I'm getting a "VISA Read in " error. I've attached pictures of the labview program and some syntax requirements from the instrument's manual.

Any ideas?

↧
↧

How to make 1D Array but with only one element filled in Real Time

June 4, 2015, 2:15 pm
$
0
0

Hi folks,

 

here I am with another question. I want to implement an prediction discrete state space observer which is going to run on a CRIO real time target. I am going to do it just like in the example which comes with LV.

 

CDEx Predictive Observer and Controller Implementation_BD.png

 

I have some questions regarding the input and outputs which in the example those are "dummy".

 

My model is a SISO model, but the function "Construct SS model" returns parameters (A,B,C,D Matrices) as 2D arrays, so once you connect the cluster model into the Discrete Observer model, it takes y and u as 1D arrays despite of the fact that there is a SISO model.

 

I realized that the function I am using in the simulations, uses 1D arrays but with only one element filled:

 

FP.png

 

Does anyone knows how to implement such 1D arrays in Real Time? I guess the way to do it is preallocating one array of zeros of size 1, and then recirculating it through some SR, and replacing the element with my real input and output, but at the dummy.vi, they are using a simple "build array"

function.

↧

find file on unknown drive letter

June 4, 2015, 2:16 pm
$
0
0

I am writing a test in TestStand and need a LV VI that will test USB communication with multiple memory sticks.  There are three different sticks with unique filenames connected to the system.  I want to read from the file to ensure proper USB communication with the stick.  The sticks enumerate with different drive letters on different test systems so I cannot hard code the drive letter portion of the path. 

 

I attached a screen shot of what I have so far.

 

In this example the drive is enumerated at F.  The filename is 3PortRackTest1.txt.  When the DriveLetter is correct and the file is found: the FileFound = 0.  When the drive letter is wrong the file will not be found and FileFound = 7.

 

I need to scroll thru all the letters for DriveLetter until the file is found (FileFound = 0) then I know how the memory stick is enumerated.  Then read the contents of the file and know USB communication is working.  How can I change the value of DriveLetter?  It is a constant.  Does LV have variables?  I am thinking, take what I have and put it in a For Loop 26 times and somehow relate the numbers 1 thru 26 to the letters (maybe an array?).  But how do I get out of the For Loop when I find the right DriveLetter?

 

Thanks,

A newbie,

Steve

 

↧

Is there a way to print documentation for LabVIEW fpga?

June 4, 2015, 2:21 pm
$
0
0

With Traditional Labview development you can print VI and get most of the information needed for refrence... But with Labview FPGA there are alot of new elements, Registers, Memory but as far as i can tell no way to generate documentation describing the data types and configuraiton of them. 

↧
Search

FPGA compiler worker

June 4, 2015, 2:43 pm
$
0
0

The FPGA compilation time in a more powerful computer turned out to be slower.

 

I read before that the FPGA compiler does not take advantage of multi core processors, but it still does not make sense to me.

 

I set the process to be high priority and affinity.

 

Any comments?

 

Thank you

 

Computer1: 16 minutes (average)

Computer2: 18 minutes (average)

 

Computer 1:

- Windows XP 32

- Intel T9400 @2.53GHz Duo

- 4G RAM

 

Computer 2:

 - Windows 7 64

 - Intel Xeon X5690 @3.47GHz Quad

 - 24G RAM

↧
↧

How would I transfer .vi's from one computer to another?

June 4, 2015, 3:16 pm
$
0
0

Dear NI community,

 

I am very new to LabVIEW, so I apologize if my terminology is lacking. I recently transferred a LabVIEW program from a Windows XP machine running LabVIEW 2010 to a Windows 7 machine running LabVIEW 2011. This program is used to control a servo through a PI C-863.10 controller while receiving data from a Keithley 2000.

 

After copying the program over,  I noticed that several of the .vi's that it needed were missing. I included a list of these below. I tried searching the Windows XP machine for the missing .vi's, but I could only find a handful of them. Where would these .vi's be stored?

 

Thank you for your help.

 

 

List of missing .vi's:

*IDN?.vi

ERR?.vi

MVR?.vi

VEL?.vi

POS?.vi

CST?.vi

SAI?.vi

LIM?.vi

TMX?.vi

TMN?.vi

REF?.vi

REF.vi

VEL.vi

MVR.vi

MPL.vi

MNL.vi

MOV.vi

DFH.vi

INI.vi

CST.vi

#24.vi

Close connection if open.vi

GCSTranslateError.vi

PI Open Interface of one system.vi

Define connected systems (Array).vi

Commanded axes connected?.vi

Define connected stages with dialog.vi

Define connected axes.vi

General wait for movement to stop.vi

Initialize Global1.vi

Global1.vi

Initialize Global2.vi

Set RON and return RON status.vi

Assign NaN for chosen axes.vi

Select values for chosen axes.vi

Substract axes array subset from axes array.vi

Define axes to command from boolean array.vi

↧

Instrument reports: Input buffer overrun (Error -363)

June 4, 2015, 3:45 pm
$
0
0

Hi all,

 

I am currently trying to control an Ametek XG 12-240 DC power supply using LabVIEW 2013. I have downloaded all of the drivers from Ametek and can communicate with the device using NI MAX. When I run the "ametek simple example.vi" to set a current and voltage level and turn on the power output, I get

 

"Error -363 occurred at Ametek XG Power Supply.lvlib:Error Query.vi 

Possible reason(s):

Instrument reports:
Input buffer overrun;"

 

I am new to LabVIEW and have not found any online solution to the problem. Any suggestions?

 

↧

High Precision Balance/Scale via USB Serial RS232 timeout error

June 4, 2015, 4:57 pm
$
0
0

Hi,

 

I am new on LabView and I have struggled to get my balance working on LabView.

I am using  a USB-Serial converter to communicate with the balance and I got it working on its vendor software on Windows XP x86. However, on Windows 7, W7 x64 and W8.1 I couldn't read any value from the balance. In all Windows versions I couldn't get it working on LabView though.

 

The error I have got on LabView is "VISA:  (Hex 0xBFFF0015) Timeout expired before operation completed." I am not even running any code, I am trying to test the communication via VISA first.

 

I have checked all the configuration parameters, such as Boud Rate, Data Bits, Stop Bits, and Parity and I have set them on my balance to be the standard.

 

Does anyone have any idea about how to solve the problem?

 

Another try I have done is, I opened the "Sample Serial.vi" and ran it and I got nothing, no reading but no error either.

 

I am using LabView 2014.

 

Thanks in advance,

 

Diego.

↧

acquiring pressure data using daq assist

June 4, 2015, 8:04 pm
$
0
0

Hi all,

I want to use DAQ Assist to measure the pressure.When i select DAQ Assist>Acquire Signals>Analogue Input>Pressure>Pressure(Bridge) then is says 'no supported devices found'

What should i do?

thanks

↧
↧

pressure sensor calibration in labview

June 4, 2015, 9:15 pm
$
0
0

Hi all,

I have a problem in calibration of pressure sensor.In attachment i am sending the data-sheet of the sensor and the block diagram i made.I used linear fit to calibrate.y axis range:0-100 bar x axis range:0-10VDC

 

Are there more accurate solutions existing?

 

Regards,

 

↧

Array

June 4, 2015, 9:49 pm
$
0
0

i'm new to lab view.I have entered my code in formula node(which I built already) and want array to given as input to node.But don't know how to proceed

↧
Search

keyboard

June 5, 2015, 12:09 am
$
0
0

Hello everyone,

 

I am using an event structure that recognizes when I press a button from the keyboard.

 

This event structure is inside a case structure and the problem arises when there is an input from the keyboard and the program is excecuting somewhere outside the case stucture. When this happens, the VI freezes and I must forze quit. 

 

I tried moving the event structure outside the case structure without any success. So...

 

I need to find a way to recognize a button pressed from keyboard without using an Event Structure.

 

Any suggestions?

 

Thankyou

 

Lorenzo

↧

Someone can help me please

June 5, 2015, 12:36 am
$
0
0

Hi everyone, i nid help ! Sry ,im new to labview programming. Just started learning. ^^"

 

Now my program is getting the data of the wind speed for every seconds once i pressed RUN and stop at the time once i pressed stop and save the data into a text file.

 

But i nid to modify to let the program run for 24 hours and get the data in every 1 minute. Example:start from 12.00 am , and end at 23.59 pm. And record down all the data every minute. And save it to a text files.

 

How do i set a starting time(Start at 12.00 am) , and let the program run for 24 hours, and reset it at 23.59pm. and save it into a text file in the end. 

 

Note:Im currently using a Data Acquisition System(CompactRIO) made by National Instruments for control system, installed with a anemometer to record down the wind speed. Using National instruments Labview 2011, version 11(32-bits) 

↧
↧

obstacle avoidance software for mobile robot

June 5, 2015, 1:04 am
$
0
0

hi everyone, i am very very new to this project that need to use the labview to do the mobile robot. i need help if you all know how to do using labview or got anyresearch that anyone of  you have. i do not know where to start as  i been struggle for days and here to seek help. do help me...

↧

Gauge indicator target mark

June 5, 2015, 5:51 am
$
0
0

Hi All,

 

Is it possible to add a "target" position to a guage indicator? For example, I am using a gauge indicator to indicate temperature from 0-100C. The process target is some temperature X (variable), I would like to programmably add a small mark or "tick" at the target temperature to indicate that it is the target temperature. See the attached picture for a quick example of what I am trying to do.

 

Thanks!

 

Andrew

↧

analog voltage generation for 1.2 ms problem

June 5, 2015, 6:17 am
$
0
0

Hi everyone,

 

I am trying to generate finite analog voltage for 1.2 ms with NI 6353 USB X by adapting an example vi, Voltage - Finite Output.vi. I have opened an thread relevant to generation here however, none replies anymore. I am testing the vi functionality with a led which is connected to one of AO channels. I realized that led always remains on with the same period of time. I attached the modified vi. For instance, when I tried to generate voltage for 3000 seconds by entering the "pulse timing [ms]", led does not remain on position for 3 seconds. I do not understand what is wrong with it? Could you help me on this?

↧
Viewing all 69214 articles
Browse latest View live
Search
<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>