A Destructive-Readout Associative Memory

The organization of an associative memory which makes use of conventional destructive-readout magnetic elements is presented. The associative memory described is word-organized; an example is an array of memory elements of 64 bits by 1024 bits. The memory is both location-addressable and content-addressable, and capable of bit-parallel search. A unique feature is its two-dimensional read/write capability, resulting (for the example) in a short-word length of 64 bits and a long-word length of 1024 bits. Such an associative memory is proposed mainly for nonnumerical data processing rather than for storage. The bit-parallel search logic is not embedded in each memory element, but is implemented for a long-word at the exterior of the memory array. As a result, this associative memory is less costly than an associative memory where parallel logic is built into each memory element. Because parallel-search logic is implemented for only one long-word, implementation of several varieties of search logic is practical. In addition to a bit-comparison logic, other logical operations (such as NAND, NOR, AND, OR) can be implemented relatively simply and less expensively.