UNIVERSITY EXAMINATIONS: 2014/2015
ORDINARY EXAMINATION FOR THE BACHELOR OF SCIENCE
IN INFORMATION TECHNOLOGY
BIT 1106 BIT 1109 COMPUTER ORGANISATION &
ARCHITECTURE – DISTANCE LEARNING
DATE: DECEMBER, 2014 TIME: 2 HOURS
INSTRUCTIONS: Answer Question ONE and any other TWO
QUESTION ONE [30 MARKS]
Compare the characteristics of SIMD and MIMD. (4 Marks)
b) What is an instruction format? Discuss different types of instruction formats.
(4 Marks)
c) Explain the stack-based architecture of a CPU with the help of a diagram. (3 Marks)
d) What is memory hierarchy? Why do we need it? (2 Marks)
e) State the characteristics of the RAM? (2 Marks)
f). Define a memory Cache? (2 Marks)
g) Define addressing modes. Classify and explain with examples. (3 Marks)
h) Multiply the following OCTAL numbers 7 and 6. (Show your working). (2 Marks)
i). State the function of the ROM BIOS. (2 Marks)
i) Write short notes on memory reference, (3 Marks)
j) A computer’s memory is composed of 8K words of 32 bits each. How many bits are
required for memory address if the smallest addressable memory unit is a word?
(3 mark)
QUESTION TWO
a) A computer’s memory is composed of 8K words of 32 bits each, and a byte is 8 bits.
How many bytes does this memory contain? (2 Marks)
b) Which programming languages has an instruction set closest to the machine language
of a computer? (2 Marks)
c). Distinguish between auto increment and auto decrement addressing mode. (2 Marks)
d). Compare RISC with CISC architecture. (8 Marks)
e). Define pipelining in microprocessor architecture and state its advantages? (6 Marks)
QUESTION THREE [20 MARKS]
a) List the key aspects in gaining the performance in pipelined systems. (4 Marks)
b) How many memory chips are needed to construct 2 M × 16 memory system
using 512 K × 8 static memory chips? (3 Marks)
c) What is virtual memory and what are the benefits of virtual memory? (4 Marks)
d) State the function of the address bus? (2 Marks)
e) Name and give the purpose of widely used bus standard. (3 Marks)
f) What are the TWO special registers in a typical computer and explain its functions.
(4 Marks)
QUESTION FOUR [20 MARKS]
a) Describe the role of system software to improve the performance of a computer.
(6 Marks)
b) Draw and explain the block diagram of a complete processor. ( 6 Marks)
c) What is the role of buffering in computer are system and give two examples?
( 4 Marks)
d) Convert the hexadecimal number F2C to binary and decimal number systems
(4 Marks)
QUESTION FIVE [20 MARKS]
a) Describe the role of cache memory in pipelined system. (6 Marks )
b) What are the different secondary storage devices? Elaborate on any one of the devices.
(4 Marks)
c) What are the needs for input-output interface? (3 Marks)
d) Explain how the virtual address is converted into real address in a paged virtual
memory system. (4 Marks)
e) Briefly describe magnetic disk principles and also the organization and accessing of
data on a disk. (3 Marks)
