read selected channel from binary file

[Moni]

Hello, I acquired data from 16 analog inputs and saved to binary file like your example Cont Acq&Graph Voltage-To File(Binary).vi and readed with your Graph Acquired Binary Data.vi. It' s ok, but how can I modify this example, if I want to read only one selected channel? Do you have some example, where it is solved?Thank you very much for your answer Monika M.

[Ed W]

Hi Moni,

If you’re just graphing the data, I would suggest simply showing the specific channels on your graph rather than explicitly reading the specific channels.  You can use the Split and Merge signals to do this, as shown in the picture below.  This was an edit of the Graph Acquired Binary Data.VI.

I hope this helps!  But if this is not a suitable solution, post back and we can figure out something else.

Ed W.

Message Edited by Ed W on 11-01-2006 04:34 PM

[Moni]

Hi, You´ve right, because I tried to read directly selected channels (my First.vi, what I append) and it´s very slow for major file. So I decided to read every data and then display only selected channels. But here I´ve got problem if I have got big file, for example 600MB, and with this file I can´t read it. LabView said I´ve got not enough memory. So I used my next program (Second.vi) where I read data piecewise (and fill array), but LabView said again I´ve got not enough memory. What can I do now? I think I can only read some data and display and forget data and again read another part of data. Do you have some idea or do I something wrong? Thank you for your answer Monika.
For illustration I append programs with small binary file (I used I16).

Message Edited by Moni on 11-06-2006 09:36 AM

[Rudi_N]

Moni:

To get around acquiring more data than you really need, you can select the specific channels you would like to read from and only acquire data from those. I believe that this will definitely help your file size. Please take a look at the attached screenshot to see how you can select multiple channels.

I hope this helps and let me know if I can help further.

Regards,

Rudi N.