BY THE YEAR 2002, it is estimated that con- sumers will buy more information appliances than PCs. 11 This new market includes small, mobile, and ergonomic devices that provide information, entertainment, and communica- tions capabilities to consumer electronics, indus- trial automation, retail automation, and medical markets. These devices require complex elec- tronic design and system integration delivered in the short time frames of consumer electronics. The system design challenge of at least the next decade is the dramatic expansion of this spec- trum of diversity and the shorter and shorter time- to-market window. Given the complexity and the constraints imposed on design time and cost, the challenge the electronics industry faces is insur- mountable unless a new design paradigm is developed and deployed that focuses on design reuse at all levels of abstraction and “correct-by- construction” transformations. An essential component of a new system design paradigm is the orthogonalization of concerns (i.e., the separation of the various aspects of design to allow more effective explo- ration of alternative solutions). The pillars of the design methodology that we have proposed over the years are the separation between func- tion (what the system is supposed to do) and architecture (how it does it) and the separation between computation and communication. Function architecture codesign The mapping of function to architecture is an essential step from conception to imple- mentation. In the recent past, the research and industrial community has paid significant atten- tion to the topic of hardware–software (HW/SW) codesign and has tackled the fol- lowing problem: how to coordinate. The prob- lem we want to solve is coordinating the design of the parts of the system to be implemented as software and the parts to be implemented as hardware, avoiding the HW/SW integration problem that has marred the electronics system industry for so long. We believe that worrying about HW/SW boundaries without considering higher levels of abstraction is the wrong approach. HW/SW design and verification hap- pen after some essential decisions have already been made, thus making the verification and Formal Models for Embedded System Design Embedded System Design 2 The authors give an overview of models of computation for embedded system design and propose a new model that supports communication-based design. Marco Sgroi University of California, Berkeley Luciano Lavagno Università di Udine, Italy Alberto Sangiovanni-Vincentelli University of California, Berkeley 0740-7475/00/$10.00 © 2000 IEEE IEEE Design & Test of Computers