Switch-Box Routing Based on Corner-Edge

Taking a 2-terminal switch-box subject to no knocked-knee rule, a routing algorithm, or rather a principle, CORNER-EDGE is proposed. it classifies a given connection requirement set into N/sub tb/, N/sub lc/, the nets connecting the opposite sides vertically and horizontally, and the rest N/sub k/. CORNER-EDGE realizes the nets of N/sub k/ first, optimally in a sense. Then, it picks up certain nets, called the top nets, from N/sub tb/ N/sub lr/ and route them alternatively, and repeat. A reasoning why such a strategy is adopted is described.