2004-05 MODEL PAPER

MCA 1.1.2

COMPUTER ORGANIZATION

First Question is Compulsory

Answer any four from the remaining

Answer all parts of any Question at one place.

Time: 3 Hrs.
Max. Marks: 100

1. (a) What is the difference between Combinational Logic and Sequential Logic?
(b) What is the t ype of control unit in 8085 Microprocessor?
(c) What is the data transfer rate of PCI bus?
(d) Distinguish between microinstruction and nanoinstruction
(e) What is IEEE 754?
(f) What is the difference between real memory and virtual memory?
(g) What do you understand by internal interrupt?

2. (a) Verify whether the expression given below is valid using algebraic method only. ab' + bc' + ca' = a'b + b'c + c'a]
(b) Design a two bit comparator that compares two 2-bit values in whole, rather than one bit at a time. The circuit has inputs X₁X₀ and Y₁Y₀ , and outputs X > Y, X = Y, and X < Y

3. (a) Show the hardware including logic gates for the control function that implements the RTL statement xy¹T₀+T₁+x¹yT₂ : A ← A+1
(b) Write 8085 assembly language program to calculate the Fibonacci value f(n), where f(0) = f(1) = 1 and f(n) = f(n-1) + f(n-2) for n > 1 Assume that n > 1 and the result will be less than 256

4. (a) Describe the mechanism of an instruction fetching, decoding and execution using flow chart?
(b) Describe the major hardware functional units of 8085 microprocessor with a neat complete functional block diagram.

5. (a) Show how nine bit micro operation field in a micro instruction can be divided into sub fields? Explain with an example.
(b) What are the functions performed by an I/O interface? Explain with an example.

6. (a) Compare and contrast isolated I/O and memory mapped I/O.
(b) Why does I/O interrupt make more efficient use of the CPU?

7. (a) Explain the need of the memory hierarchy?
(b) What is the associate memory and what kind of operation it is more suitable?

8. Write short notes on
(i) Signed Notation in Computer Arithmetic (ii) Instruction formats (iii) DMA (iv) VHDL