The improvement of the VTR project by using carry-chains and power specification

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University of New Brunswick


A Field-Programmable Gate Array (FGPA) is a type of logic chip that can be programmed after manufacturing. It is especially popular for prototyping integrated circuit designs. The Verilog-To-Routing flow is an open source CAD tool for researchers to explore different properties of hypothetical FPGA architecture. As a part of the VTR project, ODIN_II reads a Verilog file as well as an architecture file, elaborates and synthesis, to produce a BLIF file for later usage. This work enhances the VTR flow first by supporting carry chains. This requires elaboration and exploration of hard block adders during the whole CAD flow. The CAD flow is also extended by adding parameter syntax support and introducing power specification. A power specification file is processed into an equivalent power specification BLIF file. Experiments on carry chains prove that hard block adders are better to use for large-sized additions. Results also show soft adders can provide less critical path delay and area efficiency on Island-Style FPGAs.