CS2253 COMPUTER ORGANIZATION AND ARCHITECTURE QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2011

Fourth Semester

Computer Science and Engineering

CS 2253 — COMPUTER ORGANIZATION AND ARCHITECTURE

(Common to Information Technology)

(Regulation 2008)

Time : Three hours Maximum : 100 marks

Answer ALL questions

PART A — (10 × 2 = 20 marks)

1. What is an opcode? How many bits are needed to specify 32 distinct
operations?
2. Write the logic equations of a binary half adder.
3. Write the difference between Horizontal and Vertical Microinstructions.
4. In what ways the width and height of the control memory can be reduced?
5. 5 = A A A + ← 3
A B × ← 4
What hazard does the above two instructions create when executed
concurrently?
6. What are the disadvantages of increasing the number of stages in pipelined
processing?
7. What is the use of EEPROM?
8. State the hardware needed to implement the LRU in replacement algorithm.
9. What is distributed arbitration?
10. How interrupt requests from multiple devices can be handled?

PART B — (5 × 16 = 80 marks)

11. (a) With examples explain the Data transfer, Logic and Program Control
Instructions? (16)
Or
(b) Explain the Working of a Carry-Look Ahead adder. (16)
12. (a) (i) Describe the control unit organization with a separate Encoder and
Decoder functions in a hardwired control. (8)
(ii) Generate the logic circuit for the following functions and explain. (8)
..... .BR T .ADD T T Z 4 6 1 in
+ + + =
END ... ).BRN N . T .N (T .BR T .ADD T 4 5 5 7
+ + + + = .
Or
(b) Write a brief note on nano programming. (16)
13. (a) What are the hazards of conditional branches in pipelines? how it can be
resolved? (16)
Or
(b) Explain the super scalar operations with a neat diagram. (16)
14. (a) What is a mapping function? What are the ways the cache can be
mapped? (16)
Or
(b) Explain the organization and accessing of data on a Disk. (16)
15. (a) (i) How data transfers can be controlled using handshaking technique?
(8)
(ii) Explain the protocols of USB. (8)
Or
(b) How the parallel port output interface circuit works? (16)

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2010

Fourth Semester

Computer Science and Engineering

CS2253 — COMPUTER ORGANIZATION AND ARCHITECTURE

(Common to Information Technology)

(Regulation 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. Distinguish between autoincrement and autodecrement addressing mode.
2. Compare RISC with CISC architecture.
3. Under what situations the micro program counter is not incremented after a
new instruction is fetched from micro program memory?
4. What are the relative merits of horizontal and vertical microinstruction
format?
5. What is pipelining and what are the advantages of pipelining?
6. List the key aspects in gaining the performance in pipelined systems.
7. How many memory chips are needed to construct 2 M × 16 memory system
using 512 K × 8 static memory chips?
8. What is virtual memory and what are the benefits of virtual memory?
9. What is meant by bus arbitration?
10. Name and give the purpose of widely used bus standard.
PART B — (5 × 16 = 80 Marks)
11. (a) (i) Describe the role of system software to improve the performance of
a computer. (8)
(ii) Design a 4-bit adder/subtracter circuit using full adders and explain
its function. (8)
Or
(b) (i) What are the special registers in a typical computer? Explain their
purposes in detail. (8)
(ii) Design a 4-bit fast adder and explain its function in detail. (8)
12. (a) (i) Draw and explain the block diagram of a complete processor. (6)
(ii) Briefly describe the design of a hardwired control unit. (10)
Or
(b) (i) Explain the basic organization of a microprogrammed control unit
and the generation of control signals using microprogram. (12)
(ii) What are the advantages and disadvantages of hardwired and
microprogrammed control? (4)
13. (a) (i) Describe the role of cache memory in pipelined system. (8)
(ii) Discuss the influence of pipelining on instruction set design. (8)
Or
(b) What is instruction hazard? Explain the methods for dealing with the
instruction hazards. (16)
14. (a) (i) What are the different secondary storage devices? Elaborate on any
one of the devices. (8)
(ii) Explain how the virtual address is converted into real address in a
paged virtual memory system. (8)
Or
(b) (i) Explain approaches for addressing multiple-module memory
systems with suitable diagrams. (6)
(ii) Briefly describe magnetic disk principles and also the organization
and accessing of data on a disk. (10)
15. (a) (i) Describe the hardware mechanism for handling multiple interrupt
requests. (8)
(ii) What are handshaking signals? Explain the handshake control of
data transfer during input and output operation. (8)
Or
(b) (i) What are the needs for input-output interface? Explain the
functions of a typical 8-bit parallel interface in detail. (10)
(ii) Describe the USB architecture with the help of a neat diagram. (6)