Firmware on the controller performs a fast table

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Unformatted text preview: he same row to be served directly from the row buffer. For example, to read four supercells from row of a conventional DRAM, the memory controller must send four RAS/CAS requests, even though the row address is identical in each case. To read supercells from the same row of an FPM DRAM, the memory controller sends an initial RAS/CAS request, followed by three CAS requests. The initial RAS/CAS request copies row into the row buffer and returns the first supercell. The next three supercells are served directly from the row buffer, and thus more quickly than the initial supercell. Extended data out DRAM (EDO DRAM). An enhanced form of FPM DRAM that allows the individual CAS signals to be spaced closer together in time. Synchronous DRAM (SDRAM). Conventional, FPM, and EDO DRAMs are asynchronous in the sense that they communicate with the memory controller using a set of explicit control signals. SDRAM replaces many of these control signals with the rising edges of the same external clock signal that drives the memory controller. W...
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This note was uploaded on 09/02/2010 for the course ELECTRICAL 360 taught by Professor Schultz during the Spring '10 term at BYU.

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