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MODULE 4- BASIC PERIPHERALS AND THEIR INTERFACING WITH 8086
MEMORY INTERFACING Communication between processor and memory is known as interfacing with memory (RAM or ROM) memory access possible by using Memory Read signals and Memory write signals. System is associated with different memory chips ,so processor need to properly fix one among them for performing memory access operations. So need a chip selection signal for selecting a memory chip properly . All these signals are generated by a device for supporting memory access operation is known as memory interfacing unit .
Dependency Preserving Decomposition
Dependency Preserving Decomposition If we decompose a relation R into relations R1 and R2, All dependencies of R either must be a part of R1 or R2 or must be derivable from FD’s of R1 and R2 . Relation R is decomposed in to R1 and R2 with FDs F1 and F2 respectively , if the decomposition is dependency preserving then F1 U F2 =F and so ( F1 U F2 ) + =F+