Reg. No. :

Question Paper Code : 55297

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2011.

Fourth Semester

Computer Science and Engineering

CS 2252 – MICROPROCESSORS AND MICROCONTROLLERS

(Common to Information Technology)

(Regulation 2008)

Time : Three hours Maximum : 100 marks

Answer ALL questions.

PART A — (10 × 2 = 20 marks)

1. Identify the addressing mode of the following 8085 instruction.

(a) SHLD 2500H

(b) DCR E

2. Name the machine cycles needed to execute the 8085 instruction MVI

B,4FH.

3. What are the general purpose registers in 8086?

4. Give the importance of the assembler directive EVEN.

5. What are the features of closely coupled multiprocessor systems?

6. What do you mean by CCW in an I/O processor?

7. How many address lines and data lines are necessary for accessing 32Kx8

memory?

8. What is DMA?

9. What are the differences between a microprocessor and a microcontroller?

10. How is the selection of particular register bank done in 8051?

PART B —(5 × 16 = 80 marks)

11. (a) Explain the Intel 8085 Microprocessor architecture with neat

diagram.

(16)

Or

(b) (i) Discuss the different groups of instruction set of 8085 with

suitable examples. (8)

(ii) Write an 8085 ALP to find the largest number in a array of 10

data. Starting address of the array of data is 4250H. (8)

12. (a) (i) Explain the various addressing modes of 8086 processor with

suitable examples. (10)

(ii) Compare macro and procedure. (6)

Or

(b) (i) Write an 8086 ALP to find the sum of numbers in the array of

12 elements. (8)

(ii) What is BIOS? Discuss the various BIOS function calls. (8)

13.

(a)

(i)

Draw the block diagram of 8087 numeric Data processor

explain.

and

(10)

(ii) Discuss briefly the data types supported by 8087 Numeric Data

Processor. (6)

Or

(b) (i) Explain the block diagram of 8089 I/O processor. (10)

(ii) Discuss the schemes used to solve the bus arbitration problem

in multiprocessors. (6)

14. (a) Explain the 8251 USART with neat block diagram. Also explain its

mode word, command word and status word. (16)

Or

(b) Describe the block diagram of 8259 Programmable Interrupt

Controller and its priority modes. (16)

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15. (a) (i) Draw the pin diagram of 8051 microcontroller and explain the

functions of each pin. (10)

(ii) Discuss briefly the various registers in 8051 microcontroller. (6)

Or

(b) (i) Explain the interfacing of 4×4 matrix keyboard to the 8051

microcontroller with neat diagram. (10)

(ii) Briefly write about the IE and IP register in 8051

microcontroller.

(6)

———————––––

3 55297

Reg. No.:

Question Paper Code: 53100

B.E.!B.Tech. DEGREE EXAMINATION, NOVEMBER!DECEMBER 2010

Fourth Semester

Computer Science and Engineering

CS 2252 MICROPROCESSORS AND MICROCONTROLLERS

(Common to Information Technology)

(Regulation 2008)

Time : Three hours Maximum: 100 Marks

Answer ALL questions

PART A (10 x 2 =20 Marks)

1. Give any two single byte instructions that clear the accumulator register of

8085.

2. List the machine cycles involved in tho execution of the following 8085

instructions: PUSH PSW; MOV A, M.

3. List the pointer and index registers of 8086 architecture.

4. Identify the addressing modes involved in the following 8086 instructions:

MOVAX, 000SH; MOVAX, SOH [BX][SI].

5. What are the two internal sections of 8087 architecture?

6. What is the role of CCP in 8089 architecture?

7. What are the signals and instructions available in 8085 processor for serial I/O

communication?

8. What signals are required between a 8085 processor and an interrupt

controller for interrupt driven data transfer?

9. What are the functions of the following signals of 8051? ALE/PROG, PSEN.

10. What are the sources of interrupts in 8051?

PART B (5 x 16 =80 Marks)

11. (a) (i) List and explain the functions of flags in 8085 processor. (8)

(ii) Write an assembly language program using 8085 instruction set to

convert a string of ASCII characters into its hexadecimal

equivalent. (8)

Or

(b) (i) Identify the addressing modes and the number of T-states required

for the following instructions of 8085: MOV M,A LXI SP,

addr.; LDAXD;ORAB. (8)

(ii) Discuss the features of 8085 processor for the support of interrupts

and DMA. (8)

(8)

(8)

(i)

(8)

(8)

12. (a) (i) Explain the register organization of 8086 processor in detail. (8)

(ii) Describe the various addressing modes of 8086 processor with

suitable examples for each. (8)

Or

(b) (i) What is the use of interrupts in microprocessor systems? With

suitable examples explain the sequence of operations done by a

Or

(b) (i) With a neat sketch explain the general interconnections between

8086 and 8089. (10)

(ii) Distinguish between loosely coupled and closely coupled

multiprocessor systems with suitable examples. (6)

14. (a) (i) With a neat sketch, show all the interconnections required between

a 8085 processor and a RAM of size 4KB mapped in the address

range 2000H-2FFFH. (8)

(ii) Explain the data transfer on a parallel printer interface using a

timing diagram. (8)

Or

(b) (i) What are the signals a microprocessor should have to support

DI\/IA? List and explain the sequence of operations carried out

during a DIVIA transfer. (8)

(ii) Explain the four modes of keyboard operation in 8279. (8)

15. (a) (i) Bring out the features of Special Function Registers of 8051

microcontroller. (8)

(ii) With a neat sketch of a Schematic diagram, explain the functions of

various signals of 8051. (8)

Or

(b) (i) Describe the various interrupts and their associated priorities in

8051 microcontroller. (8)

(ii) Write brief notes on ADCs mid DACs along with their interface

details. (8)

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