Note : Time: 3 hours
There are six questions in this paper. Question number 1 is compulsory and carries 30 marks. Answer any three from the rest.
Question 1
(a) Simplify the following Boolean function
in product of sums form using a Karnaugh's map. Draw the resultant logic
diagram. (5)
F (A, B, C, D) = S (2, 3, 5, 6, 7, 9,
11, 14, 15)
(b) What is stack evaluation architecture machine? How many operands will be needed for typical instructions of this machine? Does Von Neumann machine fall in this category? Justify your answer. (5)
(c) What are the various displacement addressing schemes? Where are they used? Explain each one of them with the help of an example. (5)
(d) Four 8-bit registers contain the following values: (5)
RA = 11110000
RB = 11111111
RC = 10101010
RD = 10010010
What will be the values of register after each step of the following series of micro-operations executed in the sequence :
RA=RA+RB
RC = RC And RD
INCREMENT RB
LEFT SHIFT RD (Logical)
RA = RA - RC
(e) What is Cache coherence? Why does it occur? Suppose you have a uniprocessor system; can this problem occur? Justify your answer. (5)
(f) Write a program in 8086 assembly language to find that a given number (number should be positive and less than 50) is prime or not. (5)
Question 2
(a) Describe the Flynn's classification
of computers. Give example for each type, if any. (5)
(b) What is associative memory? Draw the logic diagram (for one bit)
of matching logic in an associative cell. (5)
(c) Write a program in 8086 assembly language to find the largest value
in an array of binary values. (5)
Question 3
(a) What are the reasons of having interrupts
in computers? How can the interrupts be handled in a computer? Suggest
a scheme that can handle multiple interrupts at a time. (5)
(b) What is Cache? What is set associative mapping in cache memory?
Can you replace the main memory with all Cache memory? Justify your
answer. (5)
(c) Write a program in 8086 assembly to convert all lower case characters
to upper case characters in a given string. Make suitable assumptions,
if any. (5)
Question 4
(a) Assume that you have a J-K flip-flop
circuit and all gates with you. How will you convert this J-K flip-flop
to behave like a D flip-flop? Use logic diagram for showing resulting
construction. (5)
(b) What is the need of array processors? How is the pipelining of array
processors different than that of Reduced Instruction Set Computers
pipelining? Can an array processor be used as a co-processor? Justify
your answer. (5)
(c) Write a program in 8086 assembly language to match two given strings
in reverse direction (that is, start the match from last character of
the string). (5)
Question 5
(a) Can mutual exclusion be implemented
in multiprocessor systems? If yes, then explain one such scheme; if
no, then explain the reasons. What are the difficulties in doing pipelining
of multiprocessor systems having shared memory? (5)
(b) What is micro programming? Where can it be used? How is a micro
program executed? What is the result of execution of a micro program? (5)
(c) Design a floating point double precision number for the following
requirements: (5)
Base of the number: 4 (digits 0, 1, 2,
3)
Length of mantissa: Equivalent to 3 decimal digits
Exponent: 10±20
Make suitable assumptions, if any.
Question 6
Compare and contrast the following: (15)
(a) Static RAM versus Dynamic RAM versus flash memory.
(b) Memory Interleaving versus Memory having multi-port
(c) Various types of chip organisation.
(d) Horizontal versus Vertical micro-instruction.
(e) Instruction pipelining in Reduced Instruction Set Computers versus
Instruction pipelining in Complex Instruction Set Computers.