Moved to Chinese board
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NI MAX
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optimization of cost function having more than two inputs
Hey Everyone
I need little help please, I have an optimization problem in which cost function need to optimized. This cost function have four inputs that’s values need to optimized. I understood the examples of two circles optimization and non linear spring constant that are in examples section.
The problem which I am facing is I can’t optimized four inputs at a time as according to my understanding Global optimization vi “X” inputs section can take max of two inputs. Global optimization vi only take only bundle/array of two elements however my inputs are four so how can I optimized four inputs at a time ?
Simply I don’t know Like can I do amendment in two circle example to extend it to four circles optimization, if yes than how if no then how can I find that way ?
Kind Regards...
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Set number of major ticks to a predefined value in a WaveForm Graph
Hi!
Is there any way to set the number of major ticks in a waveform graph to a fixed value (i.e. 10 major thicks : 0, 10, 20, 30,...., 100) ?
Any idea?
Thanks in advance
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Error- 1073807360 occurred at Property Node
I am trying to create a VI which reads high or low with each loop in order to trigger a camera (https://www.adafruit.com/product/3202) to take a picture. After using the MakerHub>>LINX>>LINX Firmware Wizard for Arduino Uno and correct COM port, it indicates everything is connected properly. However, when I run the VI, it indicates Error- 1073807360 occurred at property note. I conclude that the Serial port is not initializing.
I have NI VISA installed and from there installed VIPM. From VIPM I installed LINX which is what I am using in this VI so LabVIEW can communicate with the Arduino.
On another post I saw a possible solution about explicitly opening all VISA references, but I am a bit confused as to what that does as I have gotten it to work without that function (VISA Open Function) before.
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Continuous data acquisition in actor helper loop
Hi,
So, I'm trying to run a simple DAQ device (simulated) using a helper loop in the actor framework. Normally, the data read method is executed in a loop, so the only way I could think to avoid a loop inside of a loop was to place this function in the timeout event of the helper loop for this actor. This works but it causes other problems. For instance, if I add a stop event to pause the device and close all references, there is a lengthy delay between when I initiate the stop event and when the device actually receives the stop command. The delay is strongly dependent on the number of samples being read by the DAQmx Read.vi. Any ideas?
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Simple State Machine template to build a simple calculator
Hi,
I need to build a simple calculator using the simple state machine template in Labview. The requirements are
- Each calculation will be a separate state in the state machine.
- The user will choose one of the following calculations: add, subtract, multiply, divide.
- The user will input two numbers A and B with a horizontal pointer slide control.
- Provide an enumerated control on the front panel window for the user to select the operation.
I have seen different posts about creating a simple "old fashioned" calculator and I have tried following their procedure, but because the operations are enumerated controlled and the values are horizontal sliders I don't know how to set up my block diagram. Any help would be much appreciated.
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global variable and tab control
Hi everyone,
How does tab control work in global variables and how would I access the variables in different pages? I am using Labview 8.0 .
Thanks,
Kaawn
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Issue while using GOOP
hi all
i use GOOP to design object
1.i download GOOP by VIPM refer to attachement 1
2.i create two simple object ,and set relationship refer to attachement 2
3.it show error message refer to attachement 3
my question :how to solve the issue?
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How can I programmatically determine the file system?
The subject says it all, but for those interested in the backstory:
My application interfaces with a high speed digitizer. Each triggered acquisition is written to disk. The application was developed many years ago considering FAT32 limitations, namely if all files were allowed to be written to the same directory there was high risk of hitting the limit on the maximum number of files in a directory, and so the application separated files a few layers down in subdirectories. Nowadays with NTFS this isn't a problem, however the old approach is still used, and users are complaining about the pain of copying files our of the subdirectory structure.
Knowing that some hard disks are still formatted in FAT32 to this day, I want to be able to programmatically determine what file system is being used by the storage I'm writing to. If NTFS I'll switch to a much simple subdirectory structure.
Thanks!
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Toggling Digital Output Pin
I am using LabVIEW to control an arduino uno with a sensor wired to it. The sensor is a camera (https://www.adafruit.com/product/3202). My goal is to take 5 pictures at 3 second increments. Thus, I need the white wire connected to the digital I/O pin to read ground for .4s. Then, I'm assuming, some voltage for 3 seconds. The red wire is connected to 5V pin and the black to GND pin on power section of the arduino.
The VI runs as it should besides the lack of function of the Stop button. However, the camera is not taking pictures (indicated by no pictures found on the SD card and the camera not flashing red to take a picture).
The camera works when I touch ground manually.
I tried multiple digital pins on the arduino.
I have proper wiring (the arduino is on and the camera is indicating on).
I am guessing I am not understanding what the white wire is supposed to read when it is not reading low.
Any suggestions are appreciated. Thank you.
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Dsb18b20 with myRIO
I have been trying to interface dsb18b20 sensor with LabVIEW using myRIO but I don't seem to get it working. It says "no channels supported" when I try to select the physical channel as voltage, any idea how to go about?
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How can I get image from the photodetector with Labview?
Hi,
I am student and doing research on Compressive imaging for biological tissues. Recently, my Professor bought some NI Hardware(NI USB 6003) and photodiode detectors.
details of my setup is given below,
1. photodiode detectors (DET36A2 Si Amplified Detector, ThorLABS).
2. NI USB 6003 which is connected to photodetector & white light source.
3. we are making our custom software with Labview.
I want to get an image using LabVIEW, but if I use a photodetector, I can get the light intensity with ni max.
By the way, we want to get the image from the photo detector and we want to know how to program it with LabVIEW.
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Develop the API able to read the CAN data by giving specific message ID
Hi
I am new in Labview, I am trying to use "CAN Frame Channel Conversion Library 1.0.3" and "LabVIEW® API for PCAN©-Basic 4.x" to develop the API able to read the CAN data by giving specific message ID, does anyone who familiar with the APIs and know how to do? I am real appreciated if you can do me a favor, thanks.
Patrick
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Running LabVIEW with Windows Service Account in CI environment (TeamCity)
Hi,
we are trying to run LabVIEW 2017 to perform builds in a TeamCity CI environment on Windows. We have installed LabVIEW successfully on the build server and when connecting to the machine using remote desktop and a regular user account, we can run LabVIEW successfully and perform builds, either using labviewcli or by running a "Build Targets via CLI.vi" using the commandline.
However, when builds are started from the CI system, labview is started by the TeamCity CI Agent, which runs as a service using a special user account. This service account has administrative access to the machine. In this situation, LabVIEW fails to start. When running LabVIEW directly, the VI is never run. When running labviewcli, a timeout error connecting to the labview server eventually occurs, regardless of the length of the timeout configured in the labviewcli.ini. Interestingly, I can see the labview process is actually being started with the service user account, but it disappears immediately.
Unfortunately, I cannot login using the service account. Is there a way to make LabVIEW output a logfile or do you have an ideas, as to why labview might fail to start? Might this be a license issue?
Thank you and best regards,
Bart
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IEPE pressure transducer
Hi,
I'm trying to acquire a relative pressure signal via a Dytran 2200V1 IEPE pressure transducer, a cDAQ9189 and a NI 9230.
Since it's not possible to select this type of sensor using Labview which of the following alternatives should I use:
1. Voltage measurement with internal excitation (4 mA) AC coupled
2. Voltage measurement without internal excitation (0 mA) AC coupled
3. Use it as a Microphone
thanks!
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Structure évènement
Bonjour à tous,
J'ai récupéré un code ("Test.vi", ici https://forums.ni.com/t5/Community-Documents/MQTT-Driver-for-LabVIEW/ta-p/3561289, pièce jointe "mqtt_lv2013_201708181938.zip") pour réaliser une communication MQTT. Tout fonctionne fonctionne bien mais en utilisant une structure évènement. Je souhaiterai m'affranchir de cette structure pour que le programme se connecte directement et récupère les données automatiquement sans l'intervention de l'utilisateur sur l'interface comme c'est le cas dans Test.vi.
Je ne suis pas familier avec l'utilisation de la structure évènement. Du coup je ne sais pas comment obtenir la valeur s'affichant dans l'indicateur "RX TOpic" sans utiliser cette structure évènement. Concrètement, je ne sais pas à quoi relier cet indicateur.
Quelqu'un aurait il une idée?
Merci d'avance.
User
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GPIB-USB-HS+ Device Shows as USB RAW Device in MAX
Hello!
We try to install and use a GPIB-USB-HS+ interface under Windows 10 Pro x64 (Dell laptop).
After installing the latest 19.5 GPIB driver pack, via https://www.ni.com/en-us/support/downloads/drivers/download.ni-488-2.html#305442 ,
we see the problem described here:
https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000019LoOSAU&l=hu-HU
We did all the advised steps:
- Test the GPIB-USB-HS device in a different USB port
- Make sure you have the latest compatible NI-488.2 driver installed
- Make sure NI GPIB Enumeration Service, NI LXI Discovery Service, and NI Route Coordinator is running (yes all 3 of them running)
Under device manager, the device appears correctly as GPIB-USB-H+ .
We did several times remove / re-install all NI drivers too. Nothing helped so far.
We plan to reinstall Windows too soon, and try installing GPIB driver again.
Anyone had such problem previously with such hardware/driver? Did you find any proper solution?
(the same USB-GPIB interface works fine at another PC, where we have exactly the same drivers installed).
We do not use LabVIEW, we only need MAX and the GPIB driver (the device is used from under C++).
Thanks for any advice!
Regards folks! 🙂
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Brooks MFC SLA5850S Incorrect Byte count in reply error
Hello,
I am trying to communicate with Brooks MFC SLA5850S via PXIe-8341/16 using LV 2019. I am using their DLLs found online and am encountering the error "Incorrect byte count in reply". Has anyone else encountered this error before? Upon checking the command signal via a scope, we can see the command going from the NI unit to the MFC. That looks good signal wise. The response from the valve, however, doesn’t span the full 0V to 3.3V and 3.3V to 0V differential ranges, more like 0V to 1.2V and 3.3V to 1.8V ish (from a quick measure on the scope). Could this be a flow control issue (effectively the NI unit’s Transmitter not switching off when the valve is responding if I understood correctly)? Any help will be greatly appreciated.
The Brooks DLLs can be found at https://www.brooksinstrument.com/en/products/accessories-software/product-software/brooks-labview-dll
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Arbitrary waveform generation and looping that waveform
Help required, if anybody knows how to loop this waveform continuously! I tried to make this waveform using arbitrary wave generator VI. I am able to make the waveform but cannot loop it continuously.
Help in any form will be appreciated. Thanks!
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Doubt regarding Graphs
Okay, so I've posted the whole code here and I'm confused. It's basically a PID controller. I get the data from the simulator at 20packets/second(20hz, so dt=50ms) but the dt is not exact so I measure the loop iteration time as shown below and I get values b/w 45-55ms. I give this value to my SUBvi and it is shown similarly. As I give this value to my integral and derivative part in my SUBvi,
should I be multiplying it by 0.001 as I have done below?
And as you can see the waveform chart below, what is the unit of time here? is it in seconds or milliseconds?
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