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This book has been written for practicing computer designers, whether their domain is microcomputers, minicomputers, or large computers, and for those who by their contact with computer are students of design - users, programmers, designers of peripherals and memories, and students of computer engineering and computer science.

Computer engineering is a collage of different activities and disciplines, only one of which - the technical aspects (multiplier design, the behavior of synchronizer circuits, and series/parallel tradeoffs, for example) - is covered by conventional texts. This book uses the case study method to show how all the different factors (technology push, the marketplace, manufacturing, etc.) form the real-world constraints and opportunities which influence computer engineering.

Computer engineering can be thought of as a multivariable mathematical problem in which the engineer searches for an optimum within certain constraints. Unfortunately, an optimum in one variable is rarely an optimum in another, and thus a major portion of computer engineering is the search for reasonable com promises. A common method used to aid the search is to assign weights to various system variables and to seek a weighted optimum. The weights vary with the intended application. In one situation, speed might receive the maximum weight; in another, instruction set compatibility might be the most important; and in yet another, reliability might be paramount. The number of dimensions to the problem is large, and the meaningful measures for them are few. For example, the cost variable is multidimensional and includes manufacturing, development, and field support costs. In addition, there are numerous interdependencies among the variables such as the relationships between instruction set, machine organization, logic design, and circuit design. These relationships and the contraints that control the weighting of the variables change with time. For example, the cost function changes when different subsystems use different technologies, and this influences the relationships. In addition, constraints such as maintainability and

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