Register

Zeal Test

• retagged by
710 views
1 votes
1 votes
Question :

Consider a system with 20 bit physical address and direct mapped cache with 64 blocks and block size of 16 bytes To what block number does byte address 1200 mapped??
• retagged by
User Avatar

1 Answer

–1 votes
–1 votes
It will be mapped to block number 11 .

PA is divided as : 10 | 6 | 4

Division of PA : Tag = 10 bits , index =  6 bits , offset = 4 bits .

So for address 1200 take the 6 bits of index from PA i.e bits from block index and find the block number.

PA : Tag  | Index | wo

0000000001    |     001011   |   0000

So, 001011 = 11

 

Alternative way is:

 

As one block has 16 addresses so address 1200 will be in 1200/16 =75 block number.

Now this block number will be mapped to 75%64 = 11.
• edited by
User Avatar
Voting & Accepting an answer helps improve the community
← PreviousNext →
← Previous in categoryNext in category →

Related questions

7 votes
7 votes
5 answers
2
Satbir asked Jan 13, 2020
6,134 views
ISRO2020-47
How many total bits are required for a direct-mapped cache with $128$ KB of data and $1$ word block size, assuming a $32$-bit address and $1$ word size of $4$ bytes? $2$ Mbits $1.7$ Mbits $2.5$ Mbits $1.5$ Mbits
How many total bits are required for a direct-mapped cache with $128$ KB of data and $1$ word block size, assuming a $32$-bit address and $1$ word size of $4$ bytes?$2$ M...
User Avatar
0 votes
0 votes
1 answer
3
S Ram asked Jan 12, 2019
487 views
Self doubt about LRU and Direct mapping cache
Can we apply LRU policy to direct mapped cache. according to me it doesn't make any sense as eventually it will be like FIFO only as unique memory addresses are assigned to each cache line. But my doubt / confusion is can we implement LRU on direct mapped caches?
Can we apply LRU policy to direct mapped cache. according to me it doesn't make any sense as eventually it will be like FIFO only as unique memory addresses are assigned ...
User Avatar
0 votes
0 votes
0 answers
4
manisha11 asked Jan 5, 2019
214 views
Self Doubt
What does additional memory for tags refer to in Direct Mapping, Associative Mapping and Set- Associative Mapping?
What does additional memory for tags refer to in Direct Mapping, Associative Mapping and Set- Associative Mapping?
User Avatar
Link Copied!