Question

A cache has been designed such that it has 512 lines, with each line or block containing 8 words. Identify the line number, tag, and word position for the 20-bit address 94EA616 using the direct mapping method.

Answer 1

Given address = 94EA6
`_(16)`

tag = 0 * 94 ( 10010100 )

line = 0 * 1 D 4 ( 111010100 )

word position = 0*6 ( 110 )

Step-by-step explanation:

using the direct mapping method

Number of lines = 512

block size = 8 words

word offset =
`log ^(8) _(2)` = 3 bit

index bit =
`log^(512)_(2)` = 9 bit

Tag = 20 - ( index bit + word offset ) = 20 - ( 3+9) = 8 bit

Given address = 94EA6
`_(16)`

tag = 0 * 94 ( 10010100 )

line = 0 * 1 D 4 ( 111010100 )

word position = 0*6 ( 110 )