Veer Narmad South Gujarat University 2011-2nd Year B.Sc Electronics SB-0716 : - 4 - Question Paper

SB-0716

Second Year B. Sc. Examination March / April - 2011 Electronics : Paper - IV

(Digital Electronics & Microprocessor)

Time : Hours]

Instructions :

(1)

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Fillup strictly the details of signs on your answer book.

Name of the Examination :

S. Y. B. Sc.

Name of the Subject:

Electronics - 4

-Subject Code No.:

0 7 1 6

-Section No. (1,2,.....): Nil

Simplify the following expression using Boolean Laws.

and x(x + Z) + A+AZ

Add each of the following in 9s and 10s complement. -489₁₀+ 375₁₀ and (-549₁₀) + (-235₁₀)

-452 + 228 and 372 + 129

10 10 ^u ' 10 10

OR

Using K-map simplifies the following and    5+5+4

implements it using appropriate hardware

E = (> ¹> ²> ^{6 8}> ⁹> ⁿ> ¹⁴) ⁺ d(13,15)

F = ttM (0, 2, 3, 5, 7, 8, 10, 12, 14) + d(l, 9,15)

Draw the digital circuit diagram of the following expression.

ab+c[d+e)+ad+[ae+de).b

CDE + A(C+ e) + BC+ A(C+ DE)

Convert the following into its equivalent Gray code. 1110010110111₂ and 101110110101011₂

Draw the circuit diagram for the RS Flip-flop    7+5+2

and explain its working. Extend your discussion for the Clocked RS Flip-flop.

Explain the working of the D Flip-flop.

State the drawback of the RS Flip-flop.

OR

Write a program in 8085 A for finding smallest 5+5+4 number from among the five numbers stored at appropriate consecutive memory locations.

Write a program in 8085 A for finding the sum of the five numbers stored at appropriate consecutive memory locations. Program should take care of the possible 16-bit resultant sum.

State the importance of the stack and stack register.

Draw the 3-bit ripple counter and explain its working 5+6+3 with help of clock diagram.

Draw the decade counter and explain its working with help of clock diagram.

Define modulo counter.

OR

Explain the function of the state diagram with 5+5+4 suitable example.

Explain the operation of shift register.

Define State diagram and state table.

(a)    State the application of XOR and XNOR gates. 6+4+4

(b)    Prove that NAND and NOR as universal logic gates.

(c)    Design and implement half and full adder circuit.

OR

(a)    Draw and explain, in detail the architecture of 5+5+4 8085 A microprocessor.

(b)    Explain, in detail, the flag register of 8085 A microprocessor.

(c)    Explain the following instruction of 8085 A microprocessor.

ANI data , SBI data , CMP M , DAD D.

SB-0716]    3    [ 100 ]

1

   Q.l is compulsory .

2

   Abbreviations have their usual meanings.

1 Answer in brief.    14

(a)    Define parity bit.

(b)    Distinguish between synchronous and asynchronous counter.

(c)    Distinguish between combinational circuit and sequential circuit.

(d)    What do you understand by level, positive, and negative triggering of flip-flop ?

(e)    Convert 24568₁₀ and 8567₁₀ to binary number.

(f)    Encode 1101011101₂ to even parity Hamming Code.

(g)    What do you understand by Flag register in 8085 A microprocessor ?

Attachment: veer-narmad-south-gujarat-university-2011-b-sc-electronics-28527-1.pdf

Earning:   Approval pending.