Computer Architecture Solved
MCQs-Part 2
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Computer Architecture Solved MCQs-Part 2
Usually ,in MSDOS ,the primary hard disk drives has the drive letter_______
A
B
C
D
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P : “Program is a step by step execution of the instructions”. Given P, which of
the following is true ?
Program is a subset of an instruction set.
Program is a sequence of a subset of an instruction set.
Program is a partially ordered set of an instruction set.
All of the above
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The most relevant addressing mode to write position independent code
Direct mode
Indirect mode
Relative mode
Indexed mode
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An interface that provides a method for transferring binary information
between internal storage and external devices is called
I/O interface
Input interface
Output interface
I/O bus
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An interface that provides I/O transfer of data directly to and form the memory
unit and peripheral is termed as
DDA
Serial interface
BR
DMA
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In magnetic disk data organized on the plotter in a concentric sets or rings
called
Sector
Track
Head
Block
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In which addressing mode the operand is given explicitly in the instruction
Absolute
Immediate
Indirect
Direct
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The instruction: MOV CL, [BX] [DI] + 8 represents the _____ addressing mode.
Based Relative
Based Indexed
Indexed Relative
Register Indexed
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A basic instruction that can be interpreted by computer generally has
An operand and an address
A decoder and an accumulator
Sequence register and decoder
An address and decoder
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The two types of main memory are
Primary and secondary
Random and sequential
ROM and RAM
Central and peripheral
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A hardware unit which is used to monitor computer processing is
Console
Dot matrix printer
Mouse
ROM
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On receiving an interrupt from an I/O device, the CPU
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halts for predetermined time
branches off to the interrupt service routine after completion of the
current instruction
branches off to the interrupt service routine immediately
hands over control of address bus and data bus to the interrupting
device
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ADC
Add to Accumulator using carry Flag
Add to Accumulator
Add Immediate data to Accumulator
Add Immediate data to Accumulator Using carry
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The concept of pipelining is most effective in improving performance if the
tasks being performed in different stages
Require different amount of time
Require about the same amount of time
Require different amount of time with time difference between any two
tasks being same
Require different amount with time difference between any two tasks
being different
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Performance of a pipelined processor suffers if
The pipeline stages have different delays
Consecutive instructions are dependent on each other
The pipeline stages share hardware resources
All of these
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In a k-way set associative cache, the cache is divided into v sets, each of
which consists of k lines. The lines of a set are placed in sequence one after
another. The lines in set s are sequenced before the lines in set (s+1). The
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main memory blocks are numbered 0 onward. The main memory block
numbered j must be mapped to any one of the cache lines from
( j mod v)*k to ( j mod v)*k + (k -1)
( j mod v) to ( j mod v) + (k -1)
( j mod k) to ( j mod k) + (v -1)
( j mod k)* v to ( j mod k)* v + (v -1)
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For a memory system ,the cycle time is
Same as the access time
Longer than the access time
Shorter than the access time
Submultiple of the access time
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Secondary storage device which uses a delivery grooveless surface and is
encoded by the laser beam in the form of microscopic pits is called
Laser disk
Compact disk
Photo disk
Video disk
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The addressing mode used in the instruction PUSH B is
Direct
Register
Register indirect
Immediate
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The idea of cache memory is based on
The property of locality of reference
The heuristic 90-10 rule
The fact that only a small portion of a program is referenced relatively
frequently
All of these
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Where does a computer add and compare data ?
Hard disk
Floppy disk
CPU chip
Memory chip
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The speed up of a pipeline processing over an equivalent non-pipeline
processing is defined by the ratio :
A
B
C
D
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The register used as a working area in CPU is
Program counter
Instruction register
Instruction decoder
Accumulator
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The ALU of a microprocessor performs operations on 8 bit two complement
operands. What happens when the operation 7A16-A216 is performed?
Result = D816 , overflow and negative flags set
Result = D816 , negative flags set
Result = D816 ,no flags set
Result = D816 , overflow flags set
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An interrupt can be temporarily ignored by the counter is called
Vector interrupt
Non maskable interrupt
Maskable interrupt
Low priority interrupt
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A CPU generally handles an interrupt by executing an interrupt service routine
as soon as an interrupt is raised
by checking the interrupt register at the end of fetch cycle
by checking the interrupt register after finishing the executing the
current instruction
by checking the interrupt register at fixed time intervals
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A single instruction to clear lower 4 bits of the accumulator in 8085 assembly
language is
XRI OF H
A NI OH
X RI FOH
ANI OF H
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Which out of the following is not an alternative name for primary memory?
Main memory
Primary memory
Internal storage
Mass storage
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Which of the following is a sequential access device
Hard disk
Optical disk
Tape
Flash memory
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The ALU of a computer normally contains a number of high speed storage
elements called
Semi conductor
Register
Hard disk
Magnetic disk
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The control unit of computer
Performs ALU operations on the data
Controls the operation of the output devices
Is a device for manually operating the computer
Direct the other unit of computers
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WORM stands for
Write Once Read Memory
Wanted Once Read Memory
Wanted Original Read Memory
Write Original Read Memory
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The hardware in which data may be stored for a computer system is called
Register
Memory
Chip
Peripheral
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The Pentium processor was introduced
1991
1992
1993
1994
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The circumferences of the two concentric disks are divided into 100 sections
each. For the outer disk, 100 of the sections are painted red and 100 of the
sections are painted blue. For the inner disk, the sections are painted red and
blue in an arbitrary manner. It is possible to align the two disks so that of the
sections on the inner disks have their colours matched with the corresponding
section on outer disk.
100 or more
125 or more
150 or more
175 or more
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Interrupts which are initiated by an I/O drive are
Internal
External
Software
All of above
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Arithmetic shift left operation
Produces the same result as obtained with logical shift left operation
Causes the sign bit to remain always unchanged
Needs additional hardware to preserve the sign bit
Is not applicable for signed 2s complement representation
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Fetch_And_Add(X,i) is an atomic Read-Modify-Write instruction that reads the
value of
memory location X, increments it by the value i, and returns the old value of X.
It is used in the
pseudocode shown below to implement a busy-wait lock. L is an unsigned
integer shared variable
initialized to 0. The value of 0 corresponds to lock being available, while any
non-zero value corresponds to the lock being not available.
AcquireLock(L){
while (Fetch_And_Add(L,1))
L = 1;
}
ReleaseLock(L){
L = 0;
}
This implementation
fails as L can overflow
fails as L can take on a non-zero value when the lock is actually
available
works correctly but may starve some processes
works correctly without starvation
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A control character is sent at the beginning as well as at the end of each block
in the synchronous-transmission in order to
Synchronize the clock of transmitter and receiver
Supply information needed to separate the incoming bits into
individual character
Detect the error in transmission and received system.
Both (A) and (C).
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The process of entering data into a storage location
Causes variation in its address number
Adds to the contents of the location
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Is called a readout operation
Is destructive of previous contents
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Of the following, which best characterizes computers that use
memory-mapped I/O?
The computer provides special instructions for manipulating I/O ports.
I/O ports are placed at addresses on the bus and are accessed just
like other memory locations.
To perform an I/O operation, it is sufficient to place the data in an
address register and call the channel to perform the operation.
Ports are referenced only by memory-mapped instructions of the
computer and are located at hardwired memory locations.
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The desirable characteristic of a memory system is
Speed and reliability
Low power consumption
Durability and compactness
All of these
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In a k-way set associative cache, the cache is divided into v sets, each of
which consists of k lines. The lines of a set are placed in sequence one after
another. The lines in set s are sequenced before the lines in set (s+1). The
main memory blocks are numbered 0 onwards. The main memory block
numbered j must be mapped to any one of the cache lines from
( j mod v ) * k to ( j mod v ) * k + (k - 1)
( j mod v ) to ( j mod v ) + (k - 1)
( j mod k ) to ( j mod k ) + (v - 1)
( j mod k ) * v to ( j mod k ) * v + (v - 1)
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Intel 80486 was introduced in
1985
1986
1987
1989
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Which of the following are typical characteristics of a RISC machine?
Highly pipielined
Multiple register sets
Both a and b
None of these
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The amount of ROM needed to implement a 4 bit multiplier is
64 bits
128 bits
1 Kbits
2 Kbits
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On a non-pipelined sequential processor, a program segment, which is a part
of the interrupt service routine, is given to transfer 500 bytes from an I/O device
to memory.
Initialize the address register
Initialize the count to 500
LOOP: Load a byte from device
Store in memory at address given by address register
Increment the address register
Decrement the count
If count != 0 go to LOOP
Assume that each statement in this program is equivalent to a machine
instruction which takes one clock cycle to execute if it is a non-load/store
instruction. The load-store instructions take two clock cycles to execute. The
designer of the system also has an alternate approach of using the DMA
controller to implement the same transfer. The DMA controller requires 20
clock
cycles for initialization and other overheads. Each DMA transfer cycle takes
two clock cycles to transfer one byte of data from the device to the memory.
What is the approximate speedup when the DMA controller based design is
used in place of the interrupt driven program based input-output?
3.4
4.3
5.1
6.3
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A charge coupled device has
Low cost per bit
High cost per bit
Low density
None of these
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WHAT IS A REGISTER?
MEMORY
ARRAY
COUNTER
NONE
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The bus which is used to transfer data from main memory to peripheral device
is
Data bus
Input bus
DMA bus
Output bus
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