Quantcast
Channel: LabVIEW topics
Viewing all 69298 articles
Browse latest View live

Appending/saving data at intervals

$
0
0

I have a measuring computing 16bit daq I am using to record pressure data from a pressure transducer I've wrote code to save the data. I am trying to update and modify my code to save and append the data to a text file at a given interval so it wont overload and slow the computer down. I've attached the original data saving vi file and then my modified attempt at saving at a given interval. any advised or help is much appreciated

 

Charlie


Color Sensor Compatible With LabVIEW and MyRIO

$
0
0

I have started a project already, and i need a color sensor compatible with LabVIEW and has a direct type of communication with MyRIO Without Using Arduino or Intelligent brickbrick

Can i find a color sensor like that ?

cant make it work (labview, visa + arduino, ds18d20)

$
0
0

hi guys, i've been reading a lot of post on how to make it work, but still i cant make a full duplex com betwen the arduino and labview.

since my english is quite poor, i'll talk through images :3

ARDUINO SIDE

 

void loop(void)
{
  if (Serial.available()) {
    String serial_input_01  = Serial.readStringUntil(serial_input_separator);
    Serial.read();
    String serial_input_02 = Serial.readStringUntil(serial_input_separator);
    Serial.read();
    String serial_input_03  = Serial.readStringUntil(serial_input_separator);
    Serial.read();
    String serial_input_04  = Serial.readStringUntil(serial_input_terminator);
    Serial.read();
    int input_01 = serial_input_01.toInt();
    int input_02 = serial_input_02.toInt();
    int input_03 = serial_input_03.toInt();
    int input_04 = serial_input_04.toInt();

switch (input_01) {
      case 1:
        if (input_02 == 1) {
          digitalWrite(7, LOW);
        }
        if (input_02 == 2){
          digitalWrite(7, HIGH);
        }
        break;}

if i write in the serial monitor from the arduino 01,01 and hit enter digital write(7) turns off, if i write 01,02 turns on, so i guess it works right? if i wirte for instance 02,###,###,### i set the colors of an rgb led.

 

after the switch case structure:

 

 sensors.requestTemperatures();
  Serial.print("A");
  Serial.println(sensors.getTempCByIndex(0));

  int potValue = map(analogRead(potPin), 0, 1023, 0, 100);
  Serial.print("B");
  Serial.println(potValue, DEC);

  delay(250);
} // end loop

 

as you can see arduino send every loop the values of the bs18d20 and the pot 
A##.##
B###serial monitorserial monitorLABVIEW SIDEit works reading (taller.vi)it works reading (taller.vi)

 

so finally i add a switch and a visa write, but then the program does not recieve nor send a thing (and doesnt give any error)

taller-02.vitaller-02.vi

taller.vi only reads

taller-02.vi try to write

so this is it guys, i really dont know what i'm doing wrong and it's driving me crazy, any help would be appreciated... PLEASE HELP! u.u

"The installation of this application may be corrupt"- happening in both 2014 and 2016

$
0
0

So about a week ago I started getting a Windows popup when I try to launch the LabVIEW 2016 development environment. It says "The installation of this application may be corrupt. Use Add or Remove Programs in the Windows Control Panel to attempt to repair this program."

 

I tried doing as it said, but apparently I don't have the right installation media sitting around, and can't get the repair tool to run correctly. I assumed my LV installation got corrupted somehow, and was about to uninstall/reinstall when I remembered I had 2014 installed as well. I tried to run it, and got the same error.

 

It seems like some other (Windows?) component is somehow broken, which is nuking my LV installs. I can try to reinstall LabVIEW, but that's a long process I'd rather not undertake if it won't fix the issue. I'd also prefer to not reinstall Windows.

 

Any thoughts? Doing a search showed a few people with this issue that reinstalled LV to fix it, but since this affects multiple separate version installs I'm wondering if it's not a LabVIEW thing at all.

Using NI1752 smart camera from LabView

$
0
0

Hi,

    My project involves image processing using images from a NI1752 camera.  I have a Rockwell PLC which makes a tag high when image needs to be taken.  I am accessing this tag in LabView using OPC client.  I would now like to use this signal as a trigger for camera to take the image and sent it back to labview.  I dont want to use VBAI as I need to use some OpenCV functions along with it.  Hence I want to implement this completely in LabView.  Please suggest a method to do so.  How can I use IMAQ vi's to get the images from camera?

 

Best,

Gibin Joe

Degrees to Radians SUBVI

$
0
0

Hi, I am currently creating a subvi for my calculator that is suppose to convert degrees to radians. I understand the math concept but it should have 2 inputs, the number to convert and a Boolean which you do the conversion if true otherwise return the original number. I am confused as to how I wire the boolean. I also need to make an indicator on my calculator vi that can show the user if they are working in radians or degrees. Any help is appreciated.

How to filter out references to controls inside a disable diagram structure?

$
0
0

If I use the Controls[] property from a Front Panel reference it will give me an array of references for all controls regardless if they are within a disable diagram structure or not.  Is there a programmatic way for me to filter out any control references that are within a disable diagram structure? 

How to edit the signal type of the simulate ECG express VI?

$
0
0

hello,

I want to edit the signal type from the front panel of the simulate ECG express VI from the biomedical toolkit, I am using labview 2017. When i convert the express VI to a sub VI so I can change the parameters from the front panel, the signal type won't change but the rest of the parameters can be changed from the front panel. So I don't really know why this happens, I would appreciate any help.

Thank you.


Relay control does not stop

$
0
0

Hello everyone, 

The attachment is part (modified) of a large control VI. Its role is to turn on a pump when START is pressed (or when a TRUE is send from another part of the control VI, which is too complex and removed), and turn it off after a specified time. I have two while loops with one being included in the other one. The inner loops is to monitor the time and stop the pump when the preset time is reached. The second loop is to keep reading the status of START bottom (in the large control VI, this done by sending a TRUE from another part of the VI). The problem is, once started, the pump and timing runs again and again. Can anyone please provide a solution? 

 

 

Graph

$
0
0

Hello, Im having trouble with graph can someone help me?

I had multiple Data's of CURRENT & VOLTAGE, POWER & SPEED, VOLTAGE & CURRENT, etc. I plotted IV of Solar char. In my graph, but when i choose different data like of fuel cell(which has opposite X & Y compared to solar). What I have to do for that.

Pause a clock with elapsed time function

$
0
0

Hello, I'm trying to implement clock function with start/stop mechanism. I need it to be done in the way that clock is located inside the case structure (see pictures). The idea is that present time compared with previous iteration time and if it more than 1 second, difference is added to start time and written to start time terminal in elapsed time function. However, it does not work as it should. Can't find the reason. Any suggestions?

Clock1.jpgClock2.jpgClock3.jpg

DI using change detection

$
0
0

 

Dear Community,

is it possible to configure the timing of a DI task to detect the change on a counter signal?

 

Generate arbitrary pulse train on counter

$
0
0

 

Dear Community,

 

I am using an X-series DAQ to generate pulses with counters.

I am trying to understand the attached example vi. In it i set the high/low time for 2 pulses and retrigger in order to allow for a periodic generation.

What I don't understand in this vi is that the parameter "frequency" in the DAQmx-create Channel does not play any role in timing. Only the high/low times set in the DAQmx-write are relevant. Why is that so?

Thanks in advance !

Delete Table Row without affecting format of other cells using Labview?

$
0
0

I want to delete a particular row in the table and need to replace that row with other rows.

OCR not working in text rotated

$
0
0

Hi to all.

 

I am developing an application which I use OCR.

What i do in the application is:

 

1- I use IMAQ match pattern 4 VI to find the text in the image inspection.

2- I get ROI where the text is in from the output boubding box of IMAQ match pattern 4.

3- Then I do OCR using IMAQ OCR read text 4.

 

Everything works fine if the image is not rotated but when the image is rotated IMAQ match pattern 4 works fine (it can find the text rotated in the image) but OCR does not work, it can not find any characters.

By the way I set "text detection" property OCR to true for rotated characters.

 

Another information is that if I put the ROI manually on the display then OCR works fine... so I think I am doing something wrong getting the ROI and passing it to OCR...

 

Anybody can help me?

 

This is the part of my code:

pictureCode.png

And this is what happens when the image inspection is not rotated:

OCRNotRotated.png

Ant this when the image is rotated which pattern matchin can find the text but OCR does not work:

OCRRotated.png


Graph Image to Data points or array

$
0
0

I have drawn a curve with the help of paint. So I wanted the points from the graph.1507715909034..jpg

 

labview psk modulation and demodulation of a bitstream

$
0
0

i am new to labview and im trying to basically get a binary bitstream from a microcontroller, input it to labview, psk modulate it onto a carrier, send it across a channel and then receive and demodulate it to my original binary bitstream. 

 

i have the modulation toolkit and have found the PSK modulate/demodulate vi's but i have no clue how to:

 

- find a way to generate a dummy binary bitstream (to then modulate, for testing purposes)

- modulate the bitstream using PSK 

- demodulate from PSK back to a carrier

 

any help appreciated as i have been oulling my hair out for quite some time over this little project

Flush queue does not work

$
0
0

Hello everybody,

 

I tried to make error check after every case done, so when I found one, it should flush the queue of these following cases and simply goes to error handling case... But... It does not work this way. It just simply ignores the flush and then it goes to the previous cases in queue.

 

I am clipin just screenshot, since there is not much to look for in another cases, so do not kill me for not putting VI :-D.

 

Thanks a lot for help in advance

 

Martin

 

the icon of NI-DAQ doesn't appear in the tool palettes in LabVIEW 6

$
0
0

Hello,

I installed LabVIEW 6.0 first, then i installed NI-DAQ693, but the icon of DAQ assistant doesn't appear in the tool palettes in Labview.how can I resolve this probleme.

thanks,

 

stop a subVI

$
0
0

The test program runs a subVI (switch_controller.vi)  with the Run VI Invoke Node.

The programmer has set the Auto Dispose Ref to True

and the Wait Until Done to False.

 

This subVI also is inserted into a subpanel on the main VI.

 

When the program is shutting down, he does a Remove VI to unload the VI in the subpanel,

however the subVI is still running in the background.

 

How do I stop it?

 

Viewing all 69298 articles
Browse latest View live


<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>