ROMantic: Generation and Optimization of Quasi Delay-Insensitive Read-Only Memories

We describe the capabilities of and algorithms used in ROMantic, a tool for generating asynchronous read-only memory. ROMantic generates ROMs that are optimized for either power or speed. These ROMs are quasi delay-insensitive, and generated from an input file consisting of a value table. Although the algorithms used are based on previously known approaches, we present several enhancements particular to the improvement of asynchronous memory design. We present the measurements of a large set of ROMs of variable sizes in terms of performance, sizing, timing, and energy consumption. This allows future comparisons of asynchronous-layout generation tools and provides a benchmark for memory sizes typical of today’s industrial designs. ROMantic is capable of targeting a broad range of asynchronous applications. It has been used in the Lutonium project, which is an asynchronous version of the 80C51 microcontroller; and it should be useful for many types of asynchronous memory and memory architecture research.