This book is an introduction on the principles of digital logic circuits. While providing coverage to the usual topics in combinational and sequential circuit principles, it also includes a chapter on the use of the hardware description language ABEL in the design of circuits using PLDs and a chapter on computer organization. Table of Contents Number Representation, Codes, and Code Conversion. Switching Algebra and Logic Gates. Representation and Implementation of Logic Functions. Combinational Logic Design. Sequential Circuit Components. Synchronous Sequential Machines. Asynchronous Sequential Machines. Design Using Hardware Description Languages. Computer Organization. Appendix: MOSFETS and Bipolar Junction Transistors. Bibliography. Index.