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Exercise 4 - Disk Operation

Estimate the time to read a 512 bytes sector sized block from SRAM and DRAM. The access time for a doubleword stored in SRAM and DRAM is roughly 4 ns and 60 ns respectively.

Solution
A doubleword size is 8 bytes.

SRAM access time = (512/8) x 4 ns = 256 ns
DRAM access time = (512/8) x 60 ns = 3840 ns

The time required to access 512 bytes sector sized block from SRAM shall be 256 ns and from DRAM shall be 3840 ns.
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