variable time oscilloscope

[temporalnexus]

I was wondering if there exists a VI that allows me to:
1) Acquire previously logged data along with it's timeing (a 2D log file with data in 1 and timeing in other).  The data is in fact a function (waveform).
2) Display the previously logged data as a waveform on the screen.  Then mark the timeing period of the data.  So basically take a continous data and sample it at specific time (digitize it) then send just the sampled data.  But I also need to see (overlay on top of my waveform) which parts of the waveform are being sampled and thus sent.
3) In addition overlay or create another waveform display but this time showing just the digitzied data, that way I can see what the sampled output looks like (not a discreate data "chopy" set and not a continous waveform).  Also I would like to be able to modify the sampling timeing of the specific points of the waveform before the sampled data points are sent. i.e. Be able to shift the sampling timeing, add additional sample without changieng the overall sample timeing, shift the initial timeing period (instead of t=0 of the waveform I want this to start sampling at t=3s into the waveform). 
etc.

So basically is there a VI that does that and if so then where is it?

P.S.
Also it would be nice if the VI could in addition acquire the data from the live signal (via GPIB or DAQ).  Therefore it would be a 2 part capability, 1 being an allready loged data digitization and sending and 2 live data digitization and sending.

Thank you

[Jarrod_S.]

Your application is rather specific, and it is unlikely that there is a direct example available. The Example Finder in LabVIEW is a great place to start when building your custom application. Many standard use cases are already provided, and examples can of course be cut and pasted together to form a composite application with all the functionality you require.

The examples you should search for will depend on the bus that wish to acquire the data from. If it's a DAQ application, and you haven't yet started, I would strongly recommend using NI-DAQmx, our newest DAQ driver, which will greatly simplify programming and maintaining your application. With DAQ applications, the most common datatype is a waveform datatype, which contains the timing information and data in one data item, making graphing and taking specifically timed subsets easier. NI-DAQmx is not available for some legacy DAQ devices, and it only works with LabVIEW 7.0 and above.

If it's a GPIB application, then the example program will undoubtedly depend heavily on the instrument you are communicating with. The best place to start your application there is to look into downloading a Plug and Play instrument driver for your specific GPIB device. Instrument drivers are software applications (VI's in LabVIEW) that contain a great deal if not all of the functionality for your instrument. They also provide example programs that can, for instance, obtain a waveform from your oscilloscope and graph it. Go to the following link and enter the information for your instrument:

http://www.ni.com/devzone/idnet/default.htm

Finally, regarding your last point about being able to overlap a waveform on top of another, select a custom range and then send that data out, that can best be accomplished using the graph cursors of the waveform graph. You can select a range of a particular plot using the cursors, and then obtain that data using a property node of the waveform graph.

To open the Example Finder in LabVIEW, open LabVIEW and select Help >> Find Examples.