5835 - ispMACH 4000: Why did the ispMACH datasheet not provide rise and fall time?

5835 - ispMACH 4000: Why did the ispMACH datasheet not provide rise and fall time?

Lattice FPGA inputs are very fast, thus are very sensitive to noise, there is no Schmitt trigger or hysteresis option. A perfect monotonically rising edge could an arbitrarily slow rise time, but the reality is noisy. A good rule of thumb for the minimum rise time is 50mV/ns.