ShaunR

I posted this at NI with no luck. Hope someone here can help out.

I need to get continuous measurements with a PXI-4071 DMM (current measurement) and a PXI-6254 DAQ (voltage measurement) but I can't figure out how to synchronize the two measurements. I'll be sampling continuously and reading the buffer at reqular intervals to compute a running average energy so I need the two measurements to line up in time. It's possible (but not as desireable) to get the current measurement with the DAQ, but the DMM would give us a better measurement. The only way I can see to come close to what I want is to trigger both measurements, but then there will be a gap in the measurement while I read the data and setup for another trigger.

George

You need to use the RTSI.

http://zone.ni.com/devzone/cda/tut/p/id/4761

Post your DLL and source/test code so we can see first hand.

The other way of course is to have one file for each language and your software just switches between files.

This makes life a lot easier for the translators, but means you have to coordinate updates to multiple files.

Thank you for your reply. I understand that without registration, I still own the right. But for one special case, I do need a paper certification to satisfy a process. It does not seem that copyright office accepts graphical programming languages' source code, they need something "readable". Isn't LabVIEW readable? (well at least for LabVIEW programmer ). I will check out the UK office as you suggested above.

Thanks,

Irene

I think they are just being pedantic.

The purpose of registration is purely to have evidence (its irrelevent what the evidence is, be it human readable or not) that can be attributed to a date so that you can prove that you thought of it first. Its not like a patent (whole different ball game) whereby a search must be made and you need to prove it is unique and has not been thought of before. The Copyright Office is merely a "vault" where you can register evidence of your copyrightable material. The evidence will only be applicable once you (as in the copyright holder) take someone to court for infringement. Then you can use whatever tools you like (including Labview) to prove you are the original author.

Hi,

I hope I don't have to bother doing this, but was asked have to do so for a case. Is it possible at all to file a copyright registration for a software written in LabVIEW? The copyright office needs some 10 pages source code, but only readable text based... how would LabVIEW application get a text based source code? I said what about AutoCAD, they said AutoCAD can convert into script... Has anyone tried this before?

Thank you,

Irene

Copyright is an automatic right of the author unless some other contractual obligation takes precendent. It is usually sufficient to add a copyright notices to your software. The issue is only really applicable if infringement takes place and registration with a copyright office is basically registering with an authorised, third party witnessing service that can verify the date and contents of the of copyrighted material to add ammunition to your defence.

However. It is a powerful defence.

The copyright office in the UK allows online-uploading of copyright material (for a fee) and there is no requirement for the uploaded contents since it is irrelevent. They even have a "Registration Update Service" so that you can upload "in development" work as and when it changes. If you are having issues with beaurocracy in your home country I would suggest using them.

UK Copyright Services

Hi,

Have you ever read Unicode INI file with labVIEW successfully? I try to do this, but the vi always return the empty key, but if I save the ini file in ANSI format, then it's works fine!

You'll probably want these.

UFT16.zip

I prefer dlls myself, but for a single instruction it might be worth looking at CINs rather than converting a whole piece of LV code to C. Especially if you already have the code.

Theres a very good tutorial HERE

Hi,

Is anybody have experience to create MUI(multilanguage User Interface) in LabVIEW? Can you please share?

We use some vis that enable dynamically changing between certain languages like english, French, German etc. I canot share the code because they are owned by the company but (as I wrote them) I can tell you how they work. There may be others who are not restricted to share. The key is really not to "hard-code" strrings into the diagrams and takes a little bit more thought but is fairly easy to do. don't talk to me about Japanese or Chinese however...lol.

They take advantage of labels and captions for controls and indicators. The Label is used as the "tag" and the Caption is what is displayed to the user. Display strings are a bit more complicated, but not much.

A create language file vi is used to iterate through all labels in the app and save them to a" bar" separated spreadsheet file. We use the bar "|" symbol because it then allows the use of commas, semicolons etc in the text. This file is then sent off to the translators and they add the words (or phrases) for the other languages on the same line for each language (first column English, second French, third German....etc).

A change language file vi is used to load the file and iterate through all the labels changing the captions to the specific language. You have to check the control type as for things like boolean indicators, its not the caption the user sees. Job done for controls and indicators. This can be invoked at any time and the current language is saved to a config file so that the software starts up in the last used language.

Display strings in the code are always preceded with a get language file vi that takes a string as an arguement (the tag as described above) and outputs the corresponding word/phrase in whatever language is chosen to be active. I've been meaning to get around to including a digram search for these tags so they can automagically be added with the create language file vi, but I've more important fish to fry.

Thats basically it. It shouldn't take you very long to write something yourself, or I suspect others on this forum have similar tools that they can share.

The force wasn't strong with this one! He should have used the Jedi mind trick.

" This isn't the droid you are looking for....move along"

Its unlikely to be a memory issue unless you are using so much the OS has to swap to disk. It is more likely a higher priority process or hardware latency is getting in the way. Disk saving is the usual cause. Next time watch the LED hard-drive indicator when you see the time jump.

What is the camera interface? If you are using GigE,another cause can be packet collisions causing the camera to re-send. This will also appear as a latency causing your loop time to jump.

You are a very, very, very, very, very, very, very, very, wise man, Shaun.

You da' MAN! Speaking for all Brits, Ausies, Hindi's and Canucks.

Some people have no sense of humo(u)r. I hope my behavio(u)r hasn't caused our English speaking neighbo(u)rs to harbo(u)r a grudge.

Lets not let the spect®e® of conceit compromi(s)(z)e integrity and (e)(i)nsure we all get with the program(me) of coexistance and co(s)(z)iness.

Very clever poem but I couldn't bring my self to finishing it, just messed with my head too much, and I'm no critically acclaimed wordsmith or anything. I can't imagine what it must be like for an English professor to read that.

Thats what "American" english looks like to British, Australian, Indians and Canadians

Are you deploying to Vista?

You can check out the code here. I have also attached some code to calculate the XMODEM CRCs as well as the normal CRC-16.I have also attached the XMODEM-VISA.llb that I used. I am pretty sure this is the same llb referred to in the link I posted but if I recall I added the support for 1K transfers.

Nice. Well worth a point.

You know, there are only 30 millions of my bunch and there are over 300 millions of them south of the border, so I'm careful not to wake up the sleeper.

The 1812 invasion is still fresh to my mind...

Well I must say your looking very well for your age

There are actually 3 examples posted, but none of the sample solutions are very good IMHO. There is the car wash, security system, and traffic light.

I've just seen them. It stikes me that the traffic light one is a lot harder (conceptually) than the others. I'd guess that the others would take me about 1 hr from scratch, but the traffic light one I'd probably have to think for an hour first!

They are all rather poultry...or did you mean paltry

The latter. I'm a bit hard-of-thinking

I actually thought the difficulty level of the sample exams was pretty close to the real thing, but the real test had a lot more requirements so it was harder to finish in the allotted time.

More cosmetic requirements? Or more to test your specmanship?

Yes it does, but "colour" works... (It might be filtering out using a canadian or british dictionary? )

You mean "English" Dictionary

I thought of that, but the external clock signal will operate over a wide range, sampling about 500-4000 points per run at anywhere from 1000Hz down to 10 Hz. At the high end of the range I won't be guaranteed to get a pulse over a short run time. I thought about letting it free run continuously, but it's impossible to change to the hardware control and back without possibly losing data. And my customer would probably not be happy with "Not accurate, but good enough".

Ahh. Now we are changing the goal posts

I didn't say "Not accurate" I said accurate enough (do you need it accurate to 1us when each event is 1 week apart?).

But you have a choice. Buy a timer counter card (problem solved). Or sacrifice a little accuracy (maybe 0.1 hz) and do it with what you have. If you are electronically inclined, freq-volt converter chips are cheap. But you will still only be able to read the freq (i.e the voltage level) as an instantaneous value.

You can free-run (as you said) without having to switch back and forth between hardware gating. Just use the clock signal as a window event in the data stream to extract that segment.

I have a sensor (anemometer) that is outputting a TTL square wave, where the pulse frequency corresponds to the wind speed (the calibration is essentially pulses/sec --> MPH or Rev/Sec).

I am reading this through a cDAQ-9172 equipped with a 9205 AI module. I was previously planning to use it through a 9401 and use the counters on the chassis, but now those counters are used for some encoders.

There is already an externally clocked AI task running on the 9205 (which is ultimately the rate at which I need to sample the anemometer), so unless I can run two tasks with asynchronous timing simultaneously, I cannot process the the signal as analog.

So I believe this means I will need to externally convert the pulsed signal (on the order of 0-50Hz) to a voltage signal (unless someone else has a better idea).

Can anyone out there suggest a module or device for doing this? Thank you!

Jed

You could sample at a higher rate and post-process to analyse the pulse train (There are vis to estimate duty cycles, pulse frequencies etc). Not as accurate as timers, but should be good enough for your requirements. You could then just ignore the data you don't need on the slower AI channel.

Should be fine. (havn't tried what your doing but have done similar things).

There is a flashing LED x-control around somewhere here that spawns a vi dynamically as a timer which is similar to what you are tring to achieve.

Interestingly (or not as the case may be). The NI "text book" answer you can download has absolutely no documentation (no descriptions of the controls, tip-strips etc). Perhaps NI should practice what they preach.

I think it would be nice if all you guys out there that have done these exams could write a few words outlining the task given to you in your exams (i'm sure its not a car wash EVERY exam). This would give those about to take thier exams a broader view of the type and scope of tasks to expect rather than one poultry example! Maybe a separate thread?

Well, it seems no one knows this on the NI list, so maybe somebody here will.

The attached VI has two analog inputs and one analog output. An external signal generator sine wave is connected to the first analog input. This is routed to the analog output which is physically connected to the second analog input. I want fresh data every time so I've set the vi to "No Regenerator". The problem is the AO only outputs one cycle of the sine wave before stopping, even though it keeps being supplied with more sine wave. It seems if there is any gap in data being provided to it, it just shuts down.

Any ideas?

Thanks,

Ben

A bit confused. After loading your example, the regen was set to "Allow Regeneration" but in your post you say you are trying to turn it off.

Its worth noting. If "Do Not Allow Regeneration" is selected and you are in "continuous" mode. You have to write to the buffer fast enough otherwise an error will occur and the output will stop (which sounds similar to what you are experiencing.

Didn't know under what category it falls but here's the prob -- > I work with DAQ 6008 (for Measurements).

For instance , i wanna measure Voltage. But i can use only one channel in the DAQ. If I use another channel to Measure something else , It says that The DAQ is already in use.

How can I write a program that can run measurements simultaneously in 2 channels (or more) ?

How do I write this program? Am I suppose to Duplicate the DAQ VI or can I use only one VI with two exits (for the 2 channels) ?

There are plenty of examples for DAQ supplied with Labview under Hardware Input and Output->DAQmx (Use the examples Finder). You should find something there that demonstrates what you want to achiive.

That'd make it a pubic forum, not a public forum, right?

I nearly spat my coffee out on that one...lol.