Associative memory
Most memory devices store and retrieve data by addressing specific memory locations. As a result, this path often becomes the limiting factor for systems that rely on fast memory access. The time required to find an item stored in memory can be reduced considerably if the stored data item can be identified for access by the content of the data itself rather than by its address. Memory that is accessed in this way is called content-addressable memory (CAM) or associative memory. CAM provides a performance advantage over other memory search algorithms (such as binary and tree-based searches or look-aside tag buffers) by comparing the desired information against the entire list of prestored entries simultaneously, often resulting in an order-of-magnitude reduction of search time. CAMs are an outgrowth of RAM which is an integrated circuit that stores data temporarily. Data is stored in RAM at a particular location, which is called an address. In RAM, the user supplies the address and gets the data back. The number of address lines limits the depth of a memory using RAM, but the width of the memory can be extended as far as desired. With CAM, the user supplies the data and gets the address bac
This operation indicates how many tag bits are set. Often the possible answers are restricted to zero, one, or many. It is more difficult to provide an exact count if there is more than one match. 2. Relatively high cost for reasonable storage capacity Write data into all tagged words at the same time. 5. A lack of software to properly use the associative power of the memory As an example, Figure 2 shows these two registers set to search for all words that contain the pattern 1101 in bits 10 through 7, and 010 in bits 3 through 1.
Some common words found in the essay are:
Memory Introduction, Static CAM, Ternary CAM, CAM CAM, Comparand Match, CAM CAM's, Setup CAM, DATA MASK, CAM MASK, Catalog Memory, match line, bit lines, tag bits, write data, read write, memory cam, word line, match found, cross-coupled transistors, data address, word line energized, stored comparand register, static cam cell, high-bandwidth address filtering, data address cam,
Approximate Word count = 2280
Approximate Pages = 9 (250 words per page double spaced)
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