On Optimal Board-Level Routing for FPGA-based Logic Emulation

In this paper, we consider a board-level routing problem which is applicable to FPGA-based logic emulation systems such as the Realizer system [3] and the Enterprise Emulation System [5] manufactured by Quickturn Systems. For the case where all nets are two-terminal nets, we present an O(n²)-time optimal algorithm where n is the number of nets. Our algorithm guarantees 100% routing completion if the number of inter-chip signal pins on each FPGA chip in the logic emulation system is less than or equal to the number of I/O pins on the chip. Our algorithm is based on iteratively finding Euler circuits in graphs. We also prove that the routing problem with multi-terminal nets is NP-complete.