ABSTRACT
The main objective of Chapter 6 was to illustrate the design of a simple but complete computer (ASC). Simplicity was our main consideration, and so architectural alternatives possible at each stage in the design were not presented. Chapter 7 extended the input/output (I/O) subsystem of ASC in light of I/O structures found in practical machines. This chapter describes selected architectural features of some popular processors as enhancements of ASC architecture. We will concentrate on the details of instruction set, addressing modes, and register and processor structures. Architectural enhancements to the memory, control unit, and ALU are presented in subsequent chapters. For the sake of completeness, we will also provide in this chapter a brief description of a family of microprocessors from Intel Corporation. Subsequent chapters provide the details of several advanced architectural features employed in contemporary systems. We will rst distinguish between the four popular types of computer systems now available.
