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Re: cosmetic question

March 27, 2018, 1:14 pm
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You can set the control to "disabled and grayed out" if you want to prevent the user from entering values during a certain time. That's probably all you need.

 

You can use a string as indicator for the measurement and switch to "please wait" until data is received, then display the formatted value.

 

Moving controls around on the front panel is not such a great idea. Even then, you only need to do it once before the loop starts and not millions of times a second. Once the VI is running, the positions cannot be changed by the user. Your Z order is also incorrect, because the string is behind the control.

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Re: cosmetic question

March 27, 2018, 1:27 pm
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Options:

1) Disable and gray out the numeric until data is collected.

2) Use the indicators Caption to display text until data collected.  You could use the property node Caption.visible to show "Acquiring data..." until you have data, then disable the Caption.

3) Do both.

 

 

 

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Re: .net4.0

March 28, 2018, 4:47 am
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For What you are using .net?

 

You can access .dll only when it has constructors to access/call the functions.

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Re: .net4.0

March 28, 2018, 4:50 am
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Re: .net4.0

March 28, 2018, 4:51 am
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Re: .net4.0

March 28, 2018, 4:54 am
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The product manufacturer provided me with this dll asking price, he said that other people have used LabVIEW to call this file

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Re: find missing dot

March 28, 2018, 4:55 am
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I think there are dozens completely different solutions to this problem... These are just a few (partial) solutions that comes to mind...

 

If the distance between the dots is known, you can draw a slightly bigger rectangle on all the positions of the dots. Then threshold the image, so all black pixels are true. A particle analysis would reveal the locations of the broken pixels. Not very sophisticated, it's rather blunt, but could prove to be very robust. Complication for neighboring broken pixels...

 

 

All the positions are on a rotated grid. Statistics would give the rotation of the grid. Once known, you can position each particle on the grid, and the missing locations would be known afterward.

 

The broken pixel is a big black square. A template\pattern match would reveal the locations. Again complication for neighboring broken pixels...

 

A caliper could be used to calculate the rotation angle. Compensating the image, or compensating the found coordinates will easy the problem.

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Re: send F2 key using serial com connection

March 28, 2018, 4:58 am
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I don't think you can.  An F2 key is not a byte or character you can send over the serial port.  It is a special key that only the PC that is connected to that keyboard through a keyboard interface will know what to do with it.

 

You could try sending the byte 127 (decimal) which according to the ASCII table in the following link is the DEL byte:

 

https://www.asciitable.com/index/asciifull.gif&imgrefurl=https://www.asciitable.com/&h=488&w=715&tbnid=2U31hF4tTw886M:&tbnh=143&tbnw=210&usg=__eWAexmBVQe8Tf8OrNHZJjhmzrqI%3D&vet=10ahUKEwj9qcWb-o7aAhXqqFkKHWK8CiIQ9QEILTAA..i&docid=OSBfy-TcJL-niM&sa=X&ved=0ahUKEwj9qcWb-o7aAhXqqFkKHWK8CiIQ9QEILTAA

 

What is this device you are connected to giving you this screen?  I have doubts that even that would work.  You are trying to enter the BIOS which is happening at the lowest levels of this PC.  I don't think serial drivers would even be loaded yet.  At the BIOS stage, just enough drivers have been loaded to handle the screen and the keyboard connected to it.

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Re: send F2 key using serial com connection

March 28, 2018, 5:09 am
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I am trying to enter to Bios of  Linux machine (CPU).
By SERIAL from my computer (7WIN)

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Re: find missing dot

March 28, 2018, 5:13 am
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Thanks for reply. I know that problem is really complex and i am also thinking about some kind of compensation of image or coordinates. I was looking for some solution but didnt found nothing. can you explain please? 

maybe corrected image with dots is grid will help

 

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Can I transfer data through FIFO in two different myRIO FPGA Targets?

March 28, 2018, 5:17 am
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Hi Community,
         

           I am making a three-phase inverter and I need 16 discrete pulses for each phase which I'm generating through arrays with Single-Cycle Timed Loop (SCTL) and taking as output from digital pins to feed the inverter. For a second phase, these 16 pulse sequence which I have generated, I displace them by 120 degrees using array indexing and give them to another 16 digital output pins. So in order to drive three phases simultaneously, I need 48 digital output pins which I can't get through a single myRIO FPGA device (short of 8 digital pins). Then I thought to drive two phases on one myRIO FPGA and the third phase on another myRIO FPGA target.

 

But in order to operate the three-phase inverter properly (means all the three phases must displace by 120 degrees), the two myRIO FPGA targets must start at the same time and should remain in synchronization with each other. I have tried many ways to make the two FPGA targets synchronize with each other including using a digital pin for triggering the other myRIO to start at the same time through a digital button.

 

But the problem I faced was that the three phases started at the same time but within elapse of time, one phase (which is on other myRIO FPGA) gets unsynchronized with the other two phases (which are on the same myRIO). The two phases which are running through the same myRIO remain 120 degrees displaced but the other phase which is on the other myRIO travels and doesn't remain 120 degrees displaced with the other two phases.

 

I have invested so much time in order to make it synchronize but didn't find a way. Now, I'm thinking to use the 16 pulses (which I'm giving to the second phase) and feed them to another myRIO and displace them by 120 degrees using FIFO to feed the third phase of the inverter.

 

Is it possible to transfer data between two myRIO FPGA targets through FIFO? And if yes, how should I do for this application? Any other thing which I can do to make it operational?

 

I'm very desperate and my brain is hurting. Hoping to find the kind response. Thanks in anticipation.

 

Ahmad

 

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Re: Issue in calling a class and VI dynamically from exe

March 28, 2018, 5:20 am
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Add the Dynamic VI to the executable in "Always Included", In Additional Exclusion Uncheck the "Modify Project Library File.. " option. Refer the attached images for more details.

 

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Butterworth filters resources in Labview FPGA

March 28, 2018, 5:36 am
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Hi,

I have a cRIO-9030 controller (FPGA Kintex 7-70T). I have 12 input signals in it, which I read at a 10kHz frequency. Every signal has a resolution of 24 bits for the word, 16 for the integer (24,16). I have some noise in the signals due to the nature of the system, so I need to filter them. To that end, I have included a 2nd order lowpass butterworth filter for each of the signals.

 

I can't implement a multi-channel filter because I do not want to loose signal resolution.

Filter coefficients (which may vary for each signal) are calculated in the RT side and passed to the FPGA via a DMA.

 

The problem is that even with just 12 filters (my first idea was to implement band-pass filters, so I would need 24), the resources (area) taken by the filters are too high, so the compiler is not able to fit the program in the Kintex 7-70T.

 

This is the compilation summary:
Final device utilization:
Slice Registers: 120495 (82000 disponible in the FPGA)
Slice LUTs: 75800 (41000 disponible in the FPGA)

 

I find 12 signals is not an enormous quantity of data and I am surprised to see that the cRIO9030 is not able to handle 12 filters, so I was wondering whether there is another way to implement the same thing without eating all the resources of the FPGA.

 

Any advice?

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UI updates when multiple graph terminals are written to

March 28, 2018, 5:51 am
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Say I have a large number of graphs being written to via their terminals all within in the same structure. Does LV know to update the FP once all of the graph terminals are written to since they are in the same structure, or will multiple updates happen within the single structure? I'm essential wondering if defer panel updates is necessary or redundant in such a case. For example, something like this:
screenshot.png

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Re: Issue in calling a class and VI dynamically from exe

March 28, 2018, 5:55 am
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Update:

Uncheck the "Remove Unused members.." in Additional Exclusion and add the child class also in the Always included section.

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Anyone seen error 1508

March 28, 2018, 6:20 am
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Normally when I google a LabVIEW error code I don't have too many problems finding information. This one doesn't seem to have much.  If fact it's not even listed here:http://zone.ni.com/reference/en-XX/help/371361P-01/lverror/misc_lv_error_codes/

 

Luckily the explain errors comes up with the following:

 

Error 1508 occurred at an unidentified location

Possible reason(s):

LabVIEW:  Cannot change the name or path of a VI that is part of a library in its current state.

 

So here's how I'm getting this.  I have some scripting code.  It takes a class and finds a specific vi within it (a template) and then does a save as and then modifies the new vi.  Then does a saveall on the owning class.  Then loops around and does it again to save a copy as another new name.

 

The first time everything goes fine.  The second time I get error 1508.  

 

I am saving everything on the class and I'm making sure to close the vi reference between calls.  The second time through it finds the template vi correctly and the second save as path is valid.

 

Anyone have any ideas?

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Re: UI updates when multiple graph terminals are written to

March 28, 2018, 6:22 am
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You don't have to worry.  When you write to terminals, LabVIEW handles the updating of the memory space quickly.  It schedules the actual updates of the front panel in a separate process that doesn't affect the execution speed of the block diagram.  You don not need to use Defer Panel Updates in this situation.

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Re: send F2 key using serial com connection

March 28, 2018, 6:23 am
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And how would you do it if you weren't using the Win7 computer?

It would be by using a keyboard plugged into the Linux PC.

 

Serial <> Keyboard.

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Re: find missing dot

March 28, 2018, 6:28 am
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Have you looked in the LabVIEW Help, especially NI Vision Concepts Help?  Have you read about Spatial Calibration?  Are you familiar with mathematical transforms (to correct for perspective, rotation, etc.)?  If not, you should seek help from someone who likes math, vectors, matrices, etc.  If you have someone in your area with digital image processing experience, they should also be useful to consult.

 

Bob Schor

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Re: Issue in calling a class and VI dynamically from exe

March 28, 2018, 6:41 am
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Anand the idea of the plug in is to modify and extend the software functionality without changing the executable. We cannot add this in always included option.

 

This issue we facing while we add few specific LabVIEW library vis in the plugin.

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