This report describes an undergraduate course in digital subsystems. The course is divided into two major parts. Part I is entitled Electronic Circuits and Functional Units. The material in this part of the course proceeds from simple understandings of circuits to the progressively more complex functional units. Early emphasis is placed on basic properties underlying digital circuits such as simple inverters and gates. The interconnection of these gates to perform simple logic functions is illustrated by detailed consideration of useful typical logic modules. The introduction of flip-flops then leads to sequential circuits such as registers, counters, and A-D and D-A converters. Interconnection of these sequential circuits leads to consideration of larger functional units. With the student now understanding the operations and properties of the basic functional units, he is ready to proceed to Part II, Digital Subsystem Design. Part II of the course is subdivided into two sections: (1) Design Principles and Procedures, and (2) Examples of Digital Subsystem Design. Section One contains a detailed outline of the many considerations in digital subsystem design and concluded by outlining a general design procedure. Section Two contains a graded set of examples of digital subsystems. A reference section is provided for each part of the course. (BC)