A hierarchical crossbar switch includes several switch arrays, each switch array including several switch cells. Each switch cell interconnects a unique pair of signal ports and provides a bi-directional signal path between the signal ports it interconnects when switched on by an enabling signal. A first...http://www.google.com.au/patents/US5530814?utm_source=gb-gplus-sharePatent US5530814 - Bi-directional crossbar switch with control memory for selectively routing signals between pairs of signal ports
