Logic Principles of Content-Addressable Memories

This chapter contains a survey of various operations, algorithms, and system organizations by which content addressability can be embodied in memory hardware. It includes logic descriptions of searching operations, their circuit implementations, and organizational solutions for content-addressable memory (CAM) arrays that are utilized in searching operations. It may be useful to remember that these principles and solutions aim at the implementation of the following three partial functions: 1) There must exist a rapid method for braodcasting a search argument to all memory locations. 2) An individual comparison of the search argument with every stored keyword or a set of attributes must be performed. 3) All matching data and other associated information must be recollected and read out in succession.