WBUT Question Papers CS
Computer Organization B Tech Third Sem 2011-12
Time Allotted : 3 Hours
Full Marks : 70
The figures in the margin indicate full marks. ,
Candidates are required to give their answers in their own words
as Jar as practicable.
GROUP – A ( Multiple Choice Type Questions )
1. Choose the correct alternatives for the following : 10 x 1 = 10
i) How many address bit are required for a 1024 x 8 memory ?
a) 1024 b) 5
c) 10 f , d) none of these.
ii) Micro instructions are kept in
a) Main memory b) Cache memory
c) Control memory d) None of these.
iii) Booth’s algorithm for computer arithmetic is used for
a) multiplication of numbers is signed magnitude form
b) division of numbers inn signed magnitude form
c) multiplication of numbers in 2’s complement form
d division of numbers in 2’s complement form.
iv) In a microprocessor, address for the next executable instruction is stored in the
b program counter
c) instruction register d) none of these.
v) A single bus structure is primarily found in
a) Mini and micro computers
b) Large mainframe computers
c) Super computers
d) Analog computers.
vi) Cache memory is used to
a) increase performance
b) increase machine cycles
c) decrease performance
d) none of these.
vii) Instruction cycle is
viii) Equivalent hexadecimal of (76575372)g will be
ix) Associative memory is
a) a very cheap memory
b) pointer addressable memory
c) content addressable memory
d) all of these.
x) Which of the following addressing mode is used for the instruction “Push B” ?
a) Register b) Register indirect
Direct d) Immediate.
GROUP -B ( Short Answer Type Questions )
Answer any three of the following. 3×5= 15
Explain the difference between full associative and direct mapped cache mapping approaches ? Explain “write through and “write back” policies in cache ? 3 + 2
Differentiate between three, two. one and zero address
instructions with suitable examples. Explain base index addressing with example. „ 0
O + Z*
What is interrupt ? Differentiate vectored and non-veetored interrupts ?
Compare and contrast RISC and CISC architecture in brief.
What are the advantages of micro programming control over
hardwired control ? Explain the role of an operating system in brief.
3 + 2
GROUP -C ( Long Answer Type Questions )
Answer an\f three of the following. 3 x 15 = 45
Describe the major components of a digital computer with a suitable block diagram.
b) What are von Neumann concept and its bottleneck ?
c) Explain and draw a binary decrement unit.
Represent the decimal value – 7-5 inn IEEE – 754 single precision floating point formats. 5 + 4 + 3 + 3
Compare parallel adder with serial adder.
With a suitable block diagram discnss the constrnction
and working principles of an 8-bit carry-look-ahead adder. ,
c) What are the advantages of CLA over ripple carry adder ?
d) Explain the importance of a common bus system in a computer. 4 + 5 + 4 + 2
- a) Explain Booth’s multiplication algorithm with a suitable
b) \Using Booth’s algorithm multiply ( – 12 ) and ( + 6 ).
c) What do you mean by ‘guard bit’ ? 8 + 5 + 2
- a) Explain instruction cycle, machine cycle and T-states
with suitable example.
b) What are the advantages of relative addressing mode over direct address mode ?
c) Draw and explain the timing diagram for memory write operation.
d) Evaluate tjie arithmetic statement X = (A * B) / (C + D) in one, two and three address machine. 5 + 4 + 3 + 3
- Write short notes on any three of the following : 3×5
a) IAS computer
b) Concept of hand shaking in IO operation
c) Static and dynamic memory
d) DMA controller
e) Classify MRI and non-MRI instructions.