This is an exhaustively revised edition of a widely used text. Architectural, programming, and interfacing concepts and techniques are presented using the Intel 8085 as the primary microprocessor. Programming concepts are illustrated using several examples from both the 8085 and Z80, and concepts and techniques in memory system design are presented in detail. Commonly used memory types and chips such as the static RAM, EPROM, and EEPROM are described, and examples illustrate how to interface these chips with the microprocessor. Microcontrollers are discussed using the NEC 7810 series, and applications of microcontrollers, such as in the modern automobile, are presented with worked out examples.