Revision – Competency 5

Past Paper Questions

Write differences between followings

1. Volatile memory and non-volatile memory.

2. RAM and ROM

3. SRAM and DRAM 

4. DVD-RW and Flash memory

5. Register Memory and cache memory

Calculations

1. For a file of size 2000 bytes, calculate the wastage in file space due to incomplete filling of the last
cluster  (Assume that a cluster has a size of 512 bytes.)

2. For a file of size 11400 bits, calculate the wastage in file space due to incomplete filling of the last cluster (Assume that a cluster has a size of 512 bytes.)

3. Assuming a cluster size of 512 bytes calculate the percentage wastage in file space due to incomplete filling of last cluster, for the file sizes below: (i) 1000 bytes (ii) 20,000 bytes

Computer Main Memory

Normally Computers has Byte addressable main memory  – it uses x-bits addresses to access any byte in its memory

Ex- A 16-bit computer – has Byte addressable main memory
That means, it uses 16-bits addresses to access any byte in its memory

The address bus (memory bus) transports memory addresses which the processor wants to access in order to read or write data. 
Then width of the address bus – 16 bits

Maximum number of different addresses – 216 
Minimum bits required for the address – 16
Maximum number of bytes uniquely addressable – 216

Maximum usable size of memory – 216/210 = 24 = 16KB

1. If a computer system is byte addressable and uses 24-bit addresses to access any byte in its memory. What is the maximum usable size of its memory in Mega Bytes (MB)? Show all your workings clearly.

2. The memory of a computer system is byte addressable and has a maximum usable size of 4GB. What is the minimum width of its address bus in bits? Show all your workings clearly.

Write 3 main actions you should get in order to improve performance of computers. Explain all three actions.

What type of incidents you should do each of the above 3 actions?

Draw the memory hierarchy by showing the access speed, capacity and cost.

What are the typical uses of

How the CPU Cache Works. Draw it using an example.