The vast majority of computers in use today are encapsulated within other systems. In contrast to general-purpose computers that run an endless selection of software, these embedded computers are often programmed for a very specific, low-level and often mundane purpose. Low-end microcontrollers, costing as little as one dollar, are often employed by engineers in designs that utilize only a small fraction of the processing capability of the device because it is either more cost-effective than selecting an application-specific part or because programmability offers custom functionality not otherwise available. Embedded Systems Interfacing for Engineers using the Freescale HCS08 Microcontroller is a two-part book intended to provide an introduction to hardware and software interfacing for engineers. Building from a comprehensive introduction of fundamental computing concepts, the book suitable for a first course in computer organization for electrical or computer engineering students with a minimal background in digital logic and programming. In addition, this book can be valuable as a reference for engineers new to the Freescale HCS08 family of microcontrollers. The HCS08 processor architecture used in the book is relatively simple to learn, powerful enough to apply towards a wide-range of interfacing tasks, and accommodates breadboard prototyping in a laboratory using freely available and low-cost tools. In Part I: Assembly Language Programming, the programmer's model of the HSC08 family of processors is introduced. This part leads the reader from basic concepts up to implementing basic software control structures in assembly language. Instead of focusing on large-scale programs, the emphasis is on implementing small algorithms necessary to accomplish some of the more common tasks expected in small embedded systems. The first part prepares the reader with the programming skills necessary to write device drivers in and perform basic input/output processing Part II, whose emphasis is on hardware interfacing concepts. Table of Contents: Introduction to Microcomputer Organization / Programmer's Model of the HCS08 CPU / HCS08 Assembly Language Programming