Real time derivative

Hello folks,

I am preparing a labview program to acquire analog input data from a position sensor. The goal is to pass this signal through a derivative (or a general transfer function) and send it to an analog output in real time. It will be done with the USB 6211 for now.

Now, for discrete filters/derivatives/transfer functions I need the actual signal at time t=n, but also some past signals at t=n-1, n-2... The thing is that the time-stamp of each acquired signal point should also be known in order to calculate time differences. I guess that the only way to do this is to use a shift register to save past values and the "tick count". Should I place the DAmx and tick count next to each other in a stacked time loop?

Thanks

Lysander