export digital waveform+labview

[mikephys8]

Hi to everyone...I'm a newbie with labview, and I want some help for the beggining...Well I'm working on a project and for start I must use an arbitrary signal and an oscilloscope so as I can see the the graph of it(for simplicity I used a sinus in the beggining...)and then I must use an A/D converter and the digitalized output must be saved in a .txt file so that I can read it...So I wired the sinus with the A/D converter but then I cannot make the output of it compatible so that I can save it...I used the component "export waveforms to spreadsheet file.vi" but it says error diffent type of data you cannot wire a "Digital waveform" with the input of the file "1-D array of waveform(DBL)"????I used and some other components for saving in a file but it didn't go better...What did I do wrong???Please if anyone can help me...I would appreciated!!!

[freitas]

Try the "Get Waveform Components" from the "Waveform" palette!

You want the data part (Y component).. so wire it!

Best luck,

[JeffL]

Hi mikephys8,

If you have Wavform data, it is a package of the start time, the delta time, and the array of scalar values. Using the Get Waveform Components will allow you to break it down and get the components you want as is stated above.

[mikephys8]

well thank you both for your immidiate response...but although i did what freitas

 "error" with every component i have used still far...it says that i'm trying to wire different types of data...i know hardly the program, so i would prefer if you can explain me more clearly or gradually what i must do...if you think it's proper for you to find me a solution i can maybe  attach or scan a picture of what i have done so far...So please let me know if you want.

thank you for time...

Michalis V.

Postgraduate Student

Department of Informatics and Telecommunications

National & Kapodistrian University of Athens

Message Edited by mikephys8 on 09-12-2009 12:58 AM

[freitas]

Please attach the .vi so we can help you more!

Regards

[JeffL]

If you post your VI it would be helpful.

If you're getting "different types of data" error, it means you're trying to wire waveform to scalar, or different dimensioned arrays, or something like that. The context help (push CNTRL+H to open it) should tell you the two data types if you hover over it with your mouse.

[mikephys8]

I'm sorry for the delay, but i had some problems to solve with my pc...Anyway I'm sending you the .vi file...Except from what you are going to tell me, I want to ask you something:when I double click on the sine component it opens a front panel window with it's properties and initial values, etc.when I press run it shows some values in Y...but when i do the same thing with the digital to analog converter it shows neither values and signal to input nor to output..is it something i did wrong?And lastly the problem with not wiring the same type of data presented with both components that are in .vi anh have to do with exporting data to a .txt file...

Thank you again for time...

Michalis V.

Postgraduate Student

Department of Informatics and Telecommunications

National & Kapodistrian University of Athens 

[freitas]

Hi mike:

I'm not familiared with writing to files, so this program only writes one time, otherwise it would be always asking to choose file.

Take a look and see if this helps you someway.

Good luck,

[mikephys8]

Thank you for your help...Your file was quite helpful! It does not ask you only once to save the data to a file...If you push the button continuous run or put a loop, it keeps constantly asking you to save it...Anyway I did some corrections and everything seems to be fine...I changed my signal from sinus to an arbitrary, because that's what I was initially asked to do and save the data to the .txt file...The only problem I have is with the printed, in the .txt file, time...The file that you sent me writes in absolute time "t0    1/1/1904  02:00:00,000000", and although I've tried to change it from the properties of the component, when the data are been written in the .txt file the time hasn't been changed...Even when I changed time from absolute to demical, it didn't change in the file..only into the interface console...It is not so important at this time...but if you know how I can solve it, please send me an answer...I'm also sending you my new file...

Thank you again very much for your time...

Michalis V.

Postgraduate Student

Department of Informatics and Telecommunications

National & Kapodistrian University of Athens  

Message Edited by mikephys8 on 09-23-2009 08:16 PM

[mikephys8]

Hi again...I want some help...Last time I sent you "my_main.vi" file and told you that had a problem about making time to be correct in the .txt file...I haven't solved it yet, although I tried a lot to find how I can change this the txt. Anyway for now what concerns me most is that although the gragh(with the formula i use) i see in the front panel is correct when i take the data from the .txt file and paste it to a .xls file and making a graph it seems that there are pulses of the same amplitude before the visible signal i see in my front panel...I couldn't understand why this was happening but after a while i put the same formula in a grahp calculator that i have and saw that the previous pulses are not of the same amplitude, they just appear to be so because the amplitude that is set to the component isn't enough to show their whole amplitude...so they are been cut off and seem to be the same...So i tried to change the values at the x-axis but I didn't make it.The program holds some certain range(0-4) that I had initially set to it...At the bottom line I'm facing a problem to appear the rest of the graph in the component's output, and also to fix the phenomenically wrong pulses to my .txt file...Please I would appreciated if anyone can help me...Im sending you all files to have a picture of wht's going on...

Thank you for your time...

Michalis V.

Postgraduate Student

Department of Informatics and Telecommunications

National & Kapodistrian University of Athens