Max Nios input speed?

You're right, that is very slow. I can tell you that I'm able to achieve ~40Mbit/s over the ethernet. I've also been able to do ~300Mbit/s using USB. So you are nowhere near the physical limitations.

So how have you got your tasks prioritized in uCOS/II. Is it possible that your task that samples the data simply isn't running frequently enough.

My personal approach to this would be to write a little hardware module to sample the data and store it into the FIFO, then have the NIOS come and grab large chunks of data and send it off.

Jake