How do I sample a digital waveform?

[Raine]

I have a digital waveform that represents a 1-bit data stream.  The bit rate is 1Mbit/s (i.e. For a value of '1' the line is high for 1us, for '0' the line is low for 1us). 
I want to create a numeric array representation of the line by taking a sample of it every 1us and appending it into an array.

How do I set it up in LabVIEW to sample the line at 1MHz and create a 1-D numeric array of the bits?

[Yardov]

Hi Raine,

Could you clarify if you are outputing physically this digital signal? If so, what hardware you have to aquire analog signals?
If you are using hardware, then you can use one of our high speed digitizers to acquire the digital signal (since we need to sample it at least twice maximum frequency of he signal which is higher than 2 MHz). You can read more here or you can simply post back with the clarification.
Hope this helps,

[Raine]

Hi Gerardo,

I will not be outputting the digital signal.  I have a digitizer module that is sampling the digital line and creating the waveform.

I guess what I need to know is how to resample the digital waveform in software after acquisition.
I want to look at the digital waveform that I have acquired, and record its boolean value every 1us (and append it into an array).

Message Edited by Raine on 02-12-2007 01:20 PM

[Riconquistiamola]

Hi Raine,

It sounds like you're trying to keep data from previous samples in memory through the next iteration of the sampling loop, then append the new sample to the array.

Using shift registers is the most reasonable option. To create a shift register, wire your sample data to the edge of your sampling loop then right click and select Replace with Shift Register. You can then use a Build Array function to connect the shift register data with the current sampling data.

Cheers.