High frequency

Hi everyone, im pretty new with Labview, and I need a help. I would like to simulate square wave with high frequency (40MHz).
1. Can anyone help me, how can I simulate the signal (test2.vi) in a moving (time) axis?
2. I would like to catch the datas and write it into .txt or excel. I found this example (0807-LVM_Beispiel.vi). Can I get the datas like this from my 40Mhz frequency generator?
A little help would be nice. Thanks.
Attachments:
test.jpg ‏525 KB
test2.vi ‏29 KB
0807-LVM_Beispiel.vi ‏88 KB

thanks for your help.
Ive been searching, and now I've changed my test2.vi into test CIC.vi and modified it. If you may see it, im trying to simulate the signal with frequency 40MHz and, with sampling frq. 800MHz and sample rate 1000samples or max. ~300.000samples (and save it in a txt.file). Actually, my task is, that im gonna need to make a labview program that can take as many points as possible, that might be not periodic. I mean, we gonna use NI card (in near future, not bought yet) to take some input datas, and to get all the data-samples in high frequency range. Is it possible to make such a program (capture the data) without knowing in the first place which NI card that we are going to use. But i believe, we gonna buy a digitizer, digital I/O and might also mxi controller (I've looked at the offered device list) from NI. Thanks a bunch. Is it much easier after buying the devices? (like getting the device's driver and maybe program that support it).
One other question, in my test CIC.vi, im saving my points into .txt file (only the amplitude). How is the trick to take also the x-axis points (time axis) and save it in the same .txt file.
Attachments:
test CIC.vi ‏49 KB
CIC 1 sub.vi ‏21 KB
Save 1Data.vi ‏18 KB

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