Encoder resolution on fast turning shafts

[Thad House]

Originally Posted by jhersh

While much of that discussion still holds to some extent, much of it is not all that applicable given the roboRIO's vastly faster DIO, unless you have a blindingly fast encoder signal.



The roboRIO and the cRIO do / did all quadrature decoding in the FPGA. It incurs no more or less load on the system sitting unswitched vs. switching quickly.

Joe, do you know exactly what the pulses per second rating for encoders/counters in the FPGA is? I remember that the cRIO was right around 40,000, and I remember hearing that the RoboRIO was in the realm of 100,000, but I would like to know for sure. It would also be nice to have this documented somewhere if possible.

EDIT: Nevermind. I didn't see the 25ns number above. Does that mean that that the RoboRIO can take 40,000,000 edge to edge pulses per second, or am I screwing my math up somewhere. That number just seems incredibly high, but I could see it being that high.