About this previous year paper
This is the B.Tech Semester III theory examination paper for Computer Organization and Architecture (COA).
The question paper carries 100 marks and comprehensively evaluates a student’s understanding of:
Computer architecture & organization
CPU design ALU operations
Memory hierarchy Instruction cycle
Floating point arithmetic DMA & data transfer
Page replacement Microprogramming
Addressing modes Bus systems
Multiplication/Division algorithms
The paper is divided into three sections – A, B, and C, combining definitions, descriptive answers, design questions, numerical logic problems, and algorithmic applications.
SECTION A – Short Answer Questions (20 Marks)
This section contains 10 compulsory questions (2 marks each) covering:
Definition of computer architecture vs organization Bus arbitration & its types
Biasing in floating-point representation Restoring method of division
Micro-operation & microcode RISC features
Hit ratio in cache memory Page fault
Cycle stealing in DMA Vector interrupt
SECTION B – Descriptive / Analytical Questions (30 Marks)
Students must attempt any three out of five questions, each worth 10 marks.
Topics include:
Bus System Design
Drawing a 4-register, 4-bit bus system using multiplexers
Arithmetic expression evaluation using a zero-address stack-based machine
Carry Look-Ahead Adder
Principle + design of 4-bit CLA
Instruction Cycle
Flowchart + diagram of fetch–decode–execute cycle
2D RAM & 2.5D RAM
Diagram & explanation
DMA Controller
Block diagram and working of a typical DMA controller
SECTION C – Long / Technical Problem-Solving Questions (50 Marks)
There are five major questions (Q3–Q7); each contains two alternatives, and students must attempt one from each.
Q3 – Addressing Modes / Processor Organization
Evaluate effective address using:
Direct, Immediate, Relative, Register Indirect, Indexed modes
OR
Processor organization & types (Single bus, Multi-bus, Stack, GPR)
Q4 – Arithmetic Algorithms / IEEE Floating Point
Booth’s algorithm for multiplication of (20) × (–19)
OR
IEEE-754 floating point representation of –1460.125 in single & double precision
Q5 – Microprogramming / Control Unit
Microprogram sequencer: block diagram + working
OR
Hardwired vs Microprogrammed control unit + components
Q6 – Paging & Memory Chips
LRU & FIFO page replacement (for page string given on page 2)
Frames = 4
OR
Memory chip calculations for 1024×1 cell RAM:
Chips required for 1024×8
Chips required for 16 KB memory
Q7 – Data Transfer Modes
Asynchronous data transfer, strobe control & handshaking
OR
Different modes of data transfer (Programmed I/O, Interrupt-driven I/O, DMA modes)