AU Solved Paper - 50486 - set 13

AU Solved Paper - 50486

December - 2017

Microprocessors & Microcontrollers

Semester-V (EEE) - Regulation 2013

[Maximum Marks: 100

Time: Three hours]

Answer ALL questions.

PART A (10 × 2 = 20 Marks)

Q.1 What are the flags available in 8085 processor ? (Refer Two Marks Q.27 of Chapter 1)

Q.2What are the interrupts available in 8055 ?

(Refer Two Marks Q.4 of Chapter 4)

Q.3 What are the types of addressing mode in 8085 microprocessor ? (Refer Two Marks Q.12 of Chapter 2)

Q.4 Differentiate CALL instruction from JUMP instruction.  (Refer Two Marks Q.24 of Chapter 2)

Q.5 What are the addressing modes of 8051 microcontroller? (Refer Two Marks Q.22 of Chapter 15)

Q.6 What are the main features of 8051 microcontroller? (Refer section 14.2)

Q.7 Give the difference between maskable and non - maskable interrupts. (Refer Two Marks Q.9 of Chapter 4)

Q.8 How is keyword interfaced with microprocessor? (Refer section 12.9)

Q.9 What is baud rate? (Refer Two marks Q.9 of Chapter 11)

Q.10 What is duty cycle in PWM ?

Ans : Duty cycle is measured in percentage. The percentage duty cycle specifically describes the percentage of time of PWM signal is ON over an interval or period of time.

% Duty cycle = On Time / On Time + Off time × 100

PART B - (5 × 13 = 65 Marks)

Q.11 a) Explain with a neat block diagram, the architecture of 8085 microprocessor. (Refer section 1.2) [13]

OR

(b) i) Describe the interrupts of 8085 microprocessor. (Refer section 4.2) [7]

ii) Draw and explain the flag register of 8085 in brief. (Refer section 1.2.1) [6]

Q.12 a) With example, explain the different addressing modes of 8085 and the different types of instruction formats. (Refer sections 2.3 and 2.7) [13]

OR

b) Explain the operations carried out when 8085 executes the instructions: [13]

i) MOV A, M [2]

ii) XCHG [2]

iii) DAD B [2]

iv) DAA   [3]

v) LDA 6000  [2]

vi) SHLD 4000 [2]

Ans. : 1) MOV A, M: This instruction copies data from memory location whose address is specified by HL register pair into accumulator.

ii) Refer section 2.2.1

iii) DAD B: This instruction adds the contents of the BC register pair to the contents of HL register pair and stores the result in HL register pair.

iv) Refer section 2.2.2

v) Refer section 2.2.1 vi) Refer section 2.2.1

Q.13 a) i) Draw the data memory structure of 8051 microcontroller and explain. (Refer section 14.5) [7]

ii) Explain with block diagram, how to access external memory devices in 8051 based system. (Refer section 14.6) [6]

OR

b) Discuss in detail, the hardware and software support provided by 8051 for serial communication. (Refer section 16.6) [13]

Q.14 a) Draw the block diagram of 8255 (PPI) and explain its various operating modes. (Refer sections 8.3 and 8.4) [13]

OR

b) With a neat diagram, explain the internal architecture of keyboard and display controller IC 8279. (Refer section 12.5) [13].

Q.15 a) Explain with a neat diagram, the closed loop control of servomotor using microcontroller. (Not in new syllabus) [13]

OR

b) Explain the different types of instructions used in 8051 microcontroller. (Refer sections 15.2 to 15.8) [13]

PART C - (1 × 15 = 15 Marks)

Q.16 a) Explain, the interfacing concept of analog to digital conversion with 8085 microprocessor. (Refer section 13.6) [15]

OR

b) With necessary diagram, explain the different modes of operation of 8254, in detail. (Refer section 10.4) [15]