The VLSI Design Automation Assistant: What's in a Knowledge Base

The Design Automation Assistant is a knowledge-based expert-system, KBES, that generates a technology-independent list of operators, registers, data paths and control signals from an algorithmic description of a VLSI system. One merit of codifying knowledge in a KBES is that it can be easily quantified and qualified. This paper takes a retrospective on that codified knowledge base, examining what has been learned about VLSI design. It discusses both the major steps in the implementation design process and the extent to which each rule embodies domain knowledge. Finally, the paper provides an example design with typical rules from each of the major steps in the implementation design process.