Fast Input Register logic option

A logic option that implements an input register in an I/O cell that has a fast, direct connection from an I/O pin. Turning on the Fast Input Register option can help maximize I/O timing performance, for example, by permitting fast setup times. Turning off this option for a particular signal prevents the Fitter from implementing the signal automatically in an I/O cell.

This option must be assigned to either a register or an input or bidirectional pin that feeds a register or it is ignored.