WBUT Previous Years Question Papers CS
Computer Organization B Tech Third Sem 2008
Time : 3 Hours ]
I Full Marks : 70
GROUP-A (Multiple Choice Type Questions)
- Choose the correct alternatives for the following : . 10×1 = 10
J) When signed numbers Eire used In binary arithmetic then which one of the following notations would have unique representation for zero ?
a) Sign magnitude b) l’s Complement
c) 2’s Complement d) None of these. ___ J
ii) The logic circuitry in ALU is
a) entirely combinational
b) entirety sequential
c) combinational cum sequential
d) none of these.
iii) In a micro-processor, the address of the next instruction to be executed, is . stored in
a) Stack pointer
b) Address latch •
c) Program counter
d) General purpose register.
iv) The technique of placing software in a ROM semiconductor chip is called
‘ a) PROM b) EPROM
c) FIRMWARE d) Micro-Processor.
v) Cache Memory
b) increases performance
c) reduces performance
vi) Associative memory is a
a) very cheap memory c) content addressable memory d) slow memory.
vii) A single bus structure is primarily found in
a) main frames b) super computers
c) high performance machines d) mini and micro-computers.
viii) Memory mapped I/O scheme is used for the allocation of address to memories and I/O devices is used for
a) small system b) large system
c) both large and small systems d) very large system.____
ix) The convertion of ( FAFAFA ) 16 into octal form is
a) 76767676 b) 76575372
c) 76737672 d) 76727672. [
x) Which of the following addressing modes is used in the instruction PUSH B ?
a) ‘ Immediate b) Register
c) Direct d) Register Indirect.
GROUP – B ( Short Answer Type Questions )
Answer any three of the following. 3×5=15
f . .
- Show the circuit diagram for implementing the following register transfer operation. If ( ab ~ = 1 ) then R1 «- R2 else R1 <- R3, where a and b are control variables.
- What do you mean by instruction cycle, machine cycles and T states ?
- What is virtual memory ? Why is it called virtual ? Write the advantage of virtual memory. 2+1+2
- What are the advantages of microprogramming control over hardwared control ? What is the role of operating system ? » 3 + 2
- What are the different types of interrupt ? Give examples. What is programmed I/O technique? . ‘ 3 + 2
GROUP-C ( Long Answer Type Questions )
Answer any three of the following questions. 3×15 = 45
- a) What are Von Neumann concept and its bottleneck ?
b) Represent the decimal value – 7-5 in IEEE – 754 single precision floating-point format. ‘
c) Compare parallel adder with serial adder.
d) What is the necessity of guard bits ?
e) Explain and draw the 4-bit binary decrementer circuit. 4 + 3 + 4+1 + 3
- a) Draw the internal cell diagram of PROM and explain its functionality.
b) What is cache memory ? How does it increase th^ performance of a computer ? What is hit ratio ?
c) A three level memory system having cache access time of 5 nsec and disk access time of 40 nsec, has a cache hit ratio of 0-96 and main memory hit ratio
of 0-9. What should be, the main memory access time to achieve an overall
access time of 16 nsecv ? dj Define : (i) rotational latency, (ii) seek time. 4 + 4 + 5 + 2
- a) What is instruction cycle ? Draw the time diagram for memory write operation.
b) Explain the basic DMA operations for transfer of data between memory and Peripherals.
c) Evaluate the arithmetic statement X = ( A * B) / (C + D) in one, two and three address machines. 1 + 4 + 5 + 5
mapping, associative mapping and set-associative mapping cache schemes :a) Given the following, determine the size of the sub-fields in the address for direct
Main memory size 512 MB
Cache memory size 1 MB
, Address space of processor 512 MB ‘
Block size . 128 B
8 blocks in cache set.
b) Differentiate between memory mapped I/O and I/O mapped I/O.
- Write short notes on any three of the following :
a) Magnetic recording
b) Cache replacement policies
c) Non-restoring division method *
d) Addressing modes .
e) Booth’s algorithm.