Netaji Subhas Open University (NSOU) 2009 M.C.A Computer Architecture & ALP - Question Paper

MCA 2.4

MCA (2nd Semester)

Term End exam – December, 2009

Computer Architecture & ALP

Paper – 2.4

Time : three Hours Full Marks : 75

ans any 5 ques. from 7 ques..

1.a) describe "Risc" and "Cisc" processor with proper advantages and disadvantages.
[Marks 5+5 = 10]
b) Write the Risc instruction in assembly language that will reason a jump to address 3200 if
the Z (zero) status bit equal to 1.
i) using immediate mode
ii) using a relative address mode (assume that PC = 3500 [Marks 5]

2.a) Draw a space-time diagram for a six-segment pipeline showing time it takes to process
8 task and discuss. [Marks 8]

b) What is array processor, state with suitable diagrams. [Marks 7]

3.a) Write down the differences ranging from Associative Mapping, Direct Mapping and Set-
associative Mapping [Marks 6]

b) The accessstime of a cache memory is 100 ns and that of main memory 1000 ns. It is
estimated that 80 % of the memory requests are for learn and the remaining 20 % for write.
The hit ratio for learn accesses only is 0.9. A write-through procedure is used.

i) What is the avg. access time of the system considering only memory learn cycles ?
ii) What is the avg. access time of the system for both learn and write requests ?
iii) What is the hit ratio taking into consideration the write cycles ? [Marks 9]

4.a) describe Virtual Memory ? [Marks 6]

b) A virtual memory has a page size of 1K words. There are 8 pages and 4 blocks. The
associative memory page table contains the subsequent entries.

----------------------------
Page Block
----------------------------
0 3

1 1

4 2

6 0

Make a list of all virtual addresses (in decimal) that will reason a page fault if caused by
the CPU. [Marks 9]

5.a) discuss Architecture of 8086 Micro processor with suitable diagram. [Marks 10]

b) Write short note on "Flag Register". [Marks 5]

6.a) elaborate the various kinds of addressing modes available in 8086 microprocessor. discuss
in detail. [Marks 10]

b) State the 5 memory operand addressing modes. [Marks 5]

7.Explain 8086 instructions with examples [Marks 15]

a) MOV

b) IN

c) INC

d) AAS

Earning:   Approval pending.