Gujarat University
MCA Semester I
FCO
Date: 23rd January, 1998 Marks:50
Instructions:
1. Answer to the two sections should be written in separate answer books.
2. Assume suitable additional data if necessary.
3. Figures to the right indicate full marks of the question.
Section I
Q-1 a) Answer the following:
i) Convert decimal number 189.3 to octal and hexadecimal numbers. [4]
ii) Perform following operation using 2’s complement and 1’s complement.
(1101.1)2 – (110.01)2
iii) Convert hexadecimal number BA5.C to octal and decimal numbers.
iv) Perform following operation using 9’s complement.
(1859)10 – (732) 10 and (686) 10 – (2164) 10
b) Find the minimal sum of product and product of sum expression for the following using k’ map and realize
using appropriate gates. Also realize sum of product form using NAND-NAND circuit. [5]
f(A,B,C,D) = åm (0,1,2,7,8,10,13,15) + åd(9,14)
Here m represents minterms and p represents don’t care conditions.
Q-2 a) Design a full adder using appropriate gates. How can you convert this design using NAND gates only?
[4]
b) Answer the following: [4]
i) Multiply and divide following binary numbers in binary system.
10101 and 110
ii) Prove following using Boolean algebra
(A + B). (A’ + B’ + c) + A.B = A + B
iii) Convert (11010)2 into gray code.
OR
Q-2 a) Explain the design of 3 bit shift register with parallel load facility. Use suitable flipflops. [4]
b) Answer the following: [4]
i) How can you find product of sum expression from K-map.
ii) Prove the following using Boolean algebra
A’C + A’B + AB’C + BC = C + A’B
iii) Give the usefulness of Parity Bit.
Q-3 a) Explain with diagram the working of 4 – input Multiplexer. [3]
b) Explain 3 – bit Binary Up/Down Counter using JK-FlipFlops. [4]
c) How Demultiplexer differs from decoder? [1]
OR
Q-3 a) Explain with diagram the 3 to 8 decoder with enable input. [3]
b) Design a 3-bit counter using sequential logic with following counting sequence using JK- Flipflop. [5]
000, 010, 011, 111, 100 and repeat
Section II
Q-4 a) Answer the following (any four) [6]
i) How Keyboard is connected to motherboard? How it is sending data to the CPU?
ii) Explain the use of MAR, MBR and Instruction counter in Control Unit of a Computer.
iii) Explain how floating point number are represented in Computer? How they are added?
iv) Give the usefulness of tri-state buffers in BUS system of Computer.
v) Write short note on Light Pen.
b) Write short note on JK- Master Slave FlipFlop. [3]
Q-5 a) Explain with diagram the working of CRT display controller. Give also difference between text mode and
graphics mode. [3]
b) Answer the following:
i) Give the features of DMA technique. Where it is used in PC? [5]
ii) What is the difference between IMPACT and NON-IMPACT type of printer? Explain the principle of
NON-IMPACT printers.
OR
Q-5 a) Give the characteristics of Printer and explain working of Dot Matrix printer. [3]
b) Explain the difference between FDD and HDD. What is formatting of disk? How data is stored in disk?
[3]
c) Explain the use of Flag register and Segment registers in 8086. [2]
Q-6 a) Explain the architecture OR features of any 8-bit microprocessor. [4]
b) Write short notes on following: [4]
i) Register Transfer Language
ii) Use of Interrupts in PC
OR
Q-6 a) What is addressing technique? Explain in brief. [3]
b) Write short notes on following:
i) EISA Bus
ii) 68000 Microprocessor
