CAD development and routing analysis for RTL-designed FPGAs
Anyu Murakami, Maho Toyoshima, Tomoaki Sato · 2025
The collaborative design of application-specific integrated circuits (ASICs) and field-programmable gate arrays (FPGAs) enables the exploitation of the reconfigurability of FPGAs alongside the high-speed and low-power advantages of ASICs. To implement these designs, FPGAs that can be developed at the register transfer level (RTL) are essential. Since FPGAs can be implemented using hardware description languages (HDLs), it is straightforward to achieve an FPGA configuration that is optimized for specific applications. To design circuits on FPGAs, CAD tools are necessary. The FPGAs developed by the authors use selectors for the control of circuits on these FPGAs. Therefore, CAD tools for conventional FPGAs, which use switches, cannot be applied. This paper proposes a CAD tool for RTL-Designed FPGAs. The control of the FPGA routing paths is managed by the SB (Switch Block) and CB (Connection Block). The internal structure and operation of the CB differ significantly from conventional FPGAs. As a result, we developed a CAD tool for the CB to enable the analysis of its routing paths. Additionally, the paper clarifies the impact of increasing the number of connections between blocks.