In-Circuit Debugging with Dynamic Reconfiguration of FPGA Interconnects

In this work, a novel method for in-circuit debugging on FPGAs is introduced that allows the insertion of low-overhead debugging infrastructure by exploiting the technique of parameterized configurations. This allows the parameterization of the LUTs and the routing infrastructure to create a virtual network of debugging multiplexers. It aims to facilitate debugging, to increase the internal signal observability, and to reduce the debugging (area and reconfiguration) overhead. Signal ranking techniques are also introduced that classify signals that can be traced during debug. Finally, the results of the method are presented and compared with a commercial tool. The area and time results and the tradeoffs between internal signal observability and area and reconfiguration overhead are also explored.