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Error -1074395720 occurred at IMAQ Get LCD ROI

November 7, 2017, 1:34 am
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Hi guys,

I'm trying to get more robust my vi, that I use to read sequence of letter on a LED 7 segment display.

Infact the position of the seven segment in not always ripetitive, matter of a mm.

But the final routine that I use, IMAQ Read LCD, is very fussy about giving back the decimal point, if ROI is not very close to the right.

So I would like to use IMAQ Get LCD ROI, hoping it could give me a perfect ROI for IMAQ Read LCD.

(I use IMAQ Read LCD instead of IMAQ Read Single digit, because I never had the decimal point reading from "Read Single".)

But IMAQ get LCD ROI refuses to give me any good result, always Error -1074395720.

Could someone link me any example using it?

I'm also looking for a new version of "IMAQ Vision for LabVIEW - User Manual" since the last I fund is 2004 edition and only indicate that those functions exists but not more.

I've some double on the input I must give to this VI.

I'm pretty sure to give it the right image with the right global rectangle, because I add images when the LED start, and it turns on in turn each segment. This is the result:

 

 

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VirtualBench: measure rise time, fall time, two waveform delay time.

November 7, 2017, 1:36 am
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How to use labview to measure waveform's rise time, fall time, two waveform delay time.

In VirtualBench, can not find the corresponding solution.

 

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Is this bug in File I/O

November 7, 2017, 1:53 am
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Access Write only

Performed Read only but not displayed the data

not throwing any error (error 8)

 

When I wire Indicator on read out it throws an error 8.

 

why such things?

 

Please help me to get clear out of this.

 

 File Chosen during RuntimeFile Chosen during Runtime

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Cannot Receive LabVIEW UDP Data in ESP8266

November 7, 2017, 2:00 am
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I am receiving UDP data from the ESP8266 in my VI, but I cannot send data from the VI to the esp8266. Somebody can help me? 

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VI to search for specific character & check to be Integer

November 7, 2017, 2:23 am
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Hello all, i apologize if this has been asked before.

I have come up with a simple VI to grab specific characters from a string.

However I want to go 1 step further, which is to ensure that the characters are integers and not other characters.

I have no luck so far to get my VI to perform that extra task, so is there anyone who can advise me?

 

I have attached the current VI that I am using now.

Thank you.

JonKang

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Read From Spreadsheet File does not read any data into Waveform Chart Indicator

November 7, 2017, 2:24 am
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 Hello everyone,

 

I have attached a vi that I have problem with. There is no error or warning, the vi can be executed but the Read From Spreadsheet File does not display data sets in the Waveform Chart.

Can anyone debug this vi? If there is a mistake in the block diagram code, please point out to me which I should change/Why. 

 

Follow the simple instructions below after you ran the vi,

- Click "Start Configuration" button

- Click any of the boolean sensor button

- Browse and open any file

- Click "Submit" button to read the entered file into Waveform Chart

 

Thanks, looking forward to somebody's response. 

 

Regards,

nnhas

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Problem: For-loop and cluster constants

November 7, 2017, 4:32 am
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Hi everyone,

ofcourse I didnt suceed to finish my project.
I tried to make a feature that is going to repeat (cycle) the measurment process.
I did it with a for-loop and it worked, but the problem is, that "Time at the beginning" of program is going to be initialised after the 1st loop pass. How to make this make this value constant?

Thanks in advance!

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NI VISA via Ethernet

November 7, 2017, 5:49 am
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Hi All,

 

I would like to know information on payload data of Ethernet of NI VISA. Currently i am using NI VISA to communicate with device RIGOL DP832 via LAN. I am sending command *idn? to get description of device. I get required details but i am curious on how NI VISA ethernet packet works as i am creating my driver for this device.

 

I see payload length as 72 with special characters before command "*idn?" in payload data ASCII. with my driver command is of length 26(specified array length) and i see payload data as only "*idn?".

 

Could someone help me understand why i am getting this special characters in payload data of NI VISA?

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LabVIEW database error

November 7, 2017, 6:56 am
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Hello

I have a weird problem with the database connectivity toolkit. The database im working with is SQL Server and its a Teststand result database (default SQL server setup).

 

I am browsing the tables going from one result ID and poking all data related to that result. This shouldnt have anything to do with the problem, but just as a background.

 

The query im trying to execute is:

SELECT * FROM ProductionTest.dbo.STEP_RESULT WHERE ID = '{E50482A2-1B88-11E7-913A-B8E856412CF9}';

 

It generates the error:

Error -2147217900 occurred at NI_Database_API.lvlib:Conn Execute.vi

Possible reason(s):
ADO Error: 0x80040E14
Exception occured in Microsoft OLE DB Provider for SQL Server: Conversion failed when converting from a character string to uniqueidentifier. in NI_Database_API.lvlib:Conn Execute.vi

 

I have had this error a few times before and its usually just a missing character or an extra blank added to the GUID. But this doesnt seem to be the case with the select statement above. I also run this on the UUT_RESULT table first, 102 times and it works like a charm. If i execute the query in SQL Server Management Studio it works perfectly. I have tried to remove the {}-brackets just to check, same result. If i run the query in a simple test VI it works as well. But when running it inside the larger structure i get the error above. When testing the working options i literally copy the select string from a probe window, so its the same query that runs. The query above goes directly into the DB Tools Execute Query.vi.

 

I dont disconnect the database between queries, its the same one running the 102 times (and some other queries etc) before the error occurs. It always stops at the same point and on the exact same query.

 

I have tried restarting the computer just to clear any weird behaviour.

 

Anyone seen something like that before? Should i disconnect/reconnect the database connection for some odd reason?

 

Thankful for input.

 

Best Regards,

Nimgaard

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How to calculate total time taken in video?

November 7, 2017, 7:08 am
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I want to calculate the time duration of  a avi file. I have tried to do using the elapsed time.vi. The output I am getting is around 0.04s but manually if I calculate it, the video file lasts around 7s. I am confused why it is showing the wrong value.

PS:I have attached my vi below

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Unexpected behavior with Coerce To Type bullet (converting integer to enum)

November 7, 2017, 7:42 am
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I've used the "Coerce To Type" bullet in production code for a few years, believing it to be generally vetted for certain uses, even if it isn't exposed on any palettes.  (If you're unfamiliar with it, stop now and read a seven-year-old thread on the IE describing it here.)  My use for it has really been limited to conversion of an integer into an enum type.  The typical need involves receiving remote data serially and wanting to convert a recovered value back to the originator's significance, like a message ID byte, error index, etc.  My evolved practice is to always define a "sentinel" value as the last enum entry, after the last "legitimate" value, such that an out-of-range value is pinned to that entry (e.g., "invalid (>=0x1A)" would fall after an enum where the last expected value would be 0x19).

 

The attached VI (I used LV2015, but looks like the behavior is present at least in 2014 and 2016) demonstrates some behavior with LV enumerations in general, as well as case structures driven by enums, that I hadn't noticed till now, and it has implications for use of Coerce To Type.

 

The tl;dr here is that the described behavior of CTT - it coerces a numeric into the range of the enum, and "pins" to the last enum entry if the numeric is beyond the enum's range - is NOT what happens.  The enum wire retains the underlying integer value outside its defined range.  Enum indicators on such a wire APPEAR to be pinned to the last entry (even their digital displays do too), but that's misleading.  And a case structure driven by an out-of-range enum (which doesn't need a default case if all enum values have cases) will select the "default" case IF one is specified, but if there is no default, will select whichever case happens to be first in the case order.  (I never knew that rearranging case display order on the block diagram had any code generation effects - EVER.)

 

Would love to hear feedback on this.

 

Dave

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Inverting a Binary String

November 7, 2017, 9:04 am
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Morning Everyone,

 

I need to convert a 19 bit binary string into 1's compliment. (I think that's the right nomenclature?)

 

E.G. I need  1111111110000000010

To become   0000000001111111101

 

I have added a picture of my code.

 

For those curious. I am processing 32 bit ARINC-429 format words from avionics. Specifically, I am using case structures for the temperature and pressure altitude words. The sign bit is the 19th bit, and the data switches the 0s to 1s and 1s to 0s. I need to reverse this so I can convert it into my new negative engineering unit.

 

Thanks everyone!

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Executable functioning trouble

November 7, 2017, 9:12 am
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Hello everyone,

Thank you for taking time to look at this.

I have created a VI that checks the Weight of a pallet and prints out a label following certain set of conditions. The VI itself runs great however, when I try to create the executable and run the executable, it does not run (Note: Does not even run on the system that has lab-view installed in it).

The executable does not take the input of the weight parameter. I have a VISA set up in the VI and a label printer hooked up.

Please help me solve this problem. This is my first time I am using the application builder.

 

Thank you

Sudeep Puvvada

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Saving data from WaveForms over time

November 7, 2017, 9:54 am
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Hi all!,
I'm trying to save the capacitance measurements over the time, measured on WaveForms 2015 with the Analog Discovery 2. This kind of data acquisition need to be done with Labview, right? In this case, how can I do it? 

 

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Is there a way in labview to emulate or Automate TightVNC Viewer application?

November 7, 2017, 10:05 am
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We use TightVNC Viewer to Remotely control aNT01 terminal screen .

When we connect using TightVNC we get a screen in the desktop which is exact replica of NT01 terminal screen by clicking on the buttons with the mouse we can control the menu like start calibration,change machine setting etc.

I want to automate certain process and test .

I was wondering using labview could i automate the  same thing which i am doing manual now? 

 

I have attached a copy of the VNC window while running.

 

 

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Controlling a Stepper motor with DAQ module

November 7, 2017, 10:42 am
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Hello, I'm a student in electronic technologies and I need some help figuring out how to control a stepper motor with a DAQ module (NI USB-6008). We're using the digital I/O. I will attach exactly what I need to be doing and the schematic we used. I can't seem to figure out why it won't work but I need some major help with LabView. I'm always lost in this class and have no idea what I'm supposed to do. My instructor does a terrible job of helping when asked so I'm going to forums for help. 

 

Please someone explain to me how I can do this. Thanks.

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Pressure Transducer Reading Error

November 7, 2017, 12:30 pm
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I am trying to read the pressure of a system using a 3-pin pressure transducer.  Details below.

Supply Voltage: 8-28VDC (I am using 24VDC)

Range: 0-3000psig

Output: 0-5VDC

It reads the pressure from 0 to approximately 15 but then stops reading.  The transducer should read to 3000psi but it just stops at 15.

 

Attached is the VI.  Could anyone help solve this issue please?

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Create a Type Def. as following shown

November 7, 2017, 1:49 pm
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Screen Shot 2017-11-07 at 2.26.32 PM.png

What would be the purpose of this Type Def. and how can I create something similar using LabView? I don't know how to create it. 

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Functional Global Variable

November 7, 2017, 2:12 pm
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I am trying to create a FGV to store the location of the stage. Default position [x,y,z] = [0,0,0], set new position, get current position, get last position, and offset current position to [0,0,0] but don't know how to. This is what I have so far. Screen Shot 2017-11-07 at 3.08.30 PM.png

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How to determine if a trigger has been received

November 7, 2017, 2:56 pm
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I am using a USB-6002 device to start an analog output signal when triggered. How can I determine whether the task has been triggered? The analog output task could take several minutes to complete, so checking whether the task is complete is not an option.

 

I considered creating a dummy task on another channel that shares the same trigger, but completes quickly (such as reading a single sample), then check whether this task is complete. However, all of my AI and AO channels are already reserved for other tasks. I have digital IO lines available, but I don't think it's possible to configure these as part of a triggered task on the USB-6002.

 

Can anyone help me out with this?

 

Attached is a minimum working example that attempts to create a digital input task using the same trigger input as an analog output task.

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