II/BCA/203 Student's Copy
2 0 1 8
2nd Semester
BACHELOR OF COMPUTER APPLICATIONS
Paper BCA-203
Introduction to Computer Architecture and Organisation
Old Course
Full Marks 75
Time 3 hours
PART A—OBJECTIVE
Marks 25
The figures in the margin indicate full marks for the questions
SECTION—A
Marks 15
1. Tick the correct answer in the brackets provided 1×10=10
Half-adder can add
1 bit
2 bits
3 bits
4 bits
The collection of all status bit conditions in the CPU is called
Program Status Word
Processor Status Word
Program Stored Word
Processor Stored Word
/555 1 Contd.
Input or output devices attached to the computer are also called
truth table
peripheral devices
RAM
CPU
Which of the following memories is volatile?
RAM
Magnetic disk
Optical disk
Flash drive
Data are represented in the computer as
binary
unary
ternary
magnetic
The input symbolic program in the Assembler is called the
source program
object program
target program
code program
Internal interrupts are also called
external interrupt
trap
software interrupt
exception
A command issued to activate the peripheral and to inform it what to do
is
data output command
status command
control command
data input command
Binary information is represented in digital computers by physical
quantities is called
gate
interface
signal
logic unit
II/BCA/203 2 Contd.
Which of the following can store data?
ALU EXE
Flip-flop Pipeline
2. Tick whether the following statements are True or False 1×5=5
The NOR function is the complement of the OR function.
T F
The Arithmetic Logic Unit supervises the transfer of information among
the registers.
T F
The transfers of data in magnetic disk is faster than the data transfer
speed of CPU.
T F
Page fault signifies page referenced by the CPU is not in the main
memory.
T F
The program that translates an assembly language program to binary is
called Assembler.
T F
SECTION—B
Marks 10
Answer the following questions 2×5=10
1. State De Morgan's theorem.
2. What is pipelining?
3. Write the advantage of using input-output processor.
4. What is a cache memory?
5. Distinguish between machine language and assembly language.
PART B—DESCRIPTIVE
Marks 50
The figures in the margin indicate full marks for the questions
1. Write the graphic symbol and truth table for AND, OR, NOR and NOT
gates. 5
What is J-K flip-flop? Write its graphic symbol and characteristic table. 5
II/BCA/203 3 Contd.
OR
Simplify the following Boolean functions using Karnaugh mapping 5
F x ¢z y¢z¢ yz¢ xy¢
S 12, 13) d 14, 15)
What is a full adder? Write its truth table and logic diagram. 5
2. Explain the purpose of the following registers 8
Program counter Instruction register
Memory buffer register Accumulator
Explain different phases of instruction cycle. 2
OR
Differentiate between the addressing modes—implied mode and
immediate mode. 4
Differentiate between internal interrupts and external interrupts. 6
3. Write a short note on Direct Memory Access (DMA). 6
What are isolated I/O and Memory-Mapped 4
OR
Explain the strobe control and handshaking mode of asynchronous
data transfer. 6
What are synchronous and asynchronous data transfer? Explain. 4
4. What are different hierarchies in memory? Explain its advantages. 5
Explain associative mapping by giving a suitable example. 5
OR
Explain the working of synchronous counter by giving a suitable
diagram. 5
Explain by giving a suitable diagram how addresses are mapped using
paging. 5
5. What are directives? Explain the different directives supported by 8086. 6
Differentiate between linker and assembler. 4
OR
What is an interrupt? Explain different types of interrupt in the 8086
microprocessor. 5
Write an assembly language program to demonstrate data transfer. 5