Object oriented approach to CAD tool control within a design framework

Abstract

A general mechanism for decentralized control based on an object-oriented view of CAD (computer-aided design) tools is described. At the heart of this view of an open control mechanism for a CAD design framework is the CAD Tool Knowledge Object (CTKO). This approach simplifies CAD tool control within a design framework, making the framework more general, easier to use, and more capable of supporting a large population of CAD tools. This approach has been implemented in the Cadweld design framework, which includes an interactive user interface, interprocessor communication, intelligent CAD tool argument modeling, an object editor, and a backtracking system. At present, over 25 CAD tools have been incorporated into Cadweld and eventually 100 tools will be added to the framework. The tools currently in use range from PLA (programmable logic array) synthesis to layout editing, IC process fabrication, circuit simulation, and data analysis. By organizing the CAD tools to work with a more powerful design representation and allowing them to be automatically executed when necessary, the designer is freed from the more tedious aspects of design.