Name:__________________________

MODEL QUESTION PAPER

CAPE ENGINEERING COLLEGES, KERALA

FIFTH SEMESTER B.TECH DEGREE EXAMINATION, NOVEMBER 2017

Course Code: CS305 Branch & Sem : 5th Semester CS&IT

Course Name: MICROPROCESSORS AND MICROCONTROLLERS

Max. Marks: 100 Duration: 3 Hours

PART A

Answer all questions, each carries 3 marks. Marks

1 Draw and discuss flag registers of 8086 in brief? (3)

2 Explain the physical address formation in 8086? (3)

3 Mention the parameter passing mechanism of subroutines or procedures? (3)

4 Compare shift and rotate instructions? (3)

PART B

Answer any two full questions, each carries 9 marks.

5 a) Draw and discuss the read cycle timing diagram of 8086 in minimum mode? (4)

b) Describe the maximum mode operation of 8086? (5)

6 a) Find square root of a two digit number. Assume that the number is a perfect

square?

(5)

b) Specify major categories of instruction set supported by 8086 with suitable

examples?

(4)

7 a) Draw and discuss the internal block diagram of 8086? (9)

PART C

Answer all questions, each carries 3 marks.

8 Draw execution diagram of an interrupt service routine? (3)

9 Specify the role of non maskable interrupt? (3)

10 Describe two different methods of interfacing I/O devices? (3)

11 What are the modes of operation of 8255? (3)

PART D

Answer any two full questions, each carries 9 marks.

12 a) Draw internal architecture of 8257 with brief description of register

organization?

(9)

13 a) Specify the significance of strobed bidirectional I/O mode of 8255? (3)

b) Mention different modes of operation of 8279? (6)

Studoob.in - Where Learning is Entertainment

14 a) Design an interface between 8086 CPU and two chips of 16KX8 EPROM and

two chips of 32KX8 RAM. Select starting address of EPROM suitable. The

RAM address must start at 00000H.

(9)

PART E

Answer any four full questions, each carries 10 marks.

15 Give brief description of memory and I/O addressing of 8051? (10)

16 Draw the internal architecture of 8051 with brief description? (10)

17 What are different addressing modes supported by 8051? (10)

18 With neat diagram, describe the interrupt structure of 8051? (10)

19 Draw and explain the internal architecture of 8254/8253? (10)

20 Write an assembly language program to count the number of 1's and 0's in a

given 8-bit number?

(10)

****

Studoob.in - Where Learning is Entertainment

MODEL EXAMINATION - ANSWERS

CAPE ENGINEERING COLLEGES, KERALA

FIFTH SEMESTER B.TECH DEGREE EXAMINATION, NOVEMBER 2017

Course Code: CS305 Branch & Sem : 5th Semester CS&IT

Course Name: MICROPROCESSORS AND MICROCONTROLLERS

Max. Marks: 100 Duration: 3 Hours

…………………………………………………………………………………………………………………………………………………………

PART A

(Answer all questions, each carries 3 mark)

1 Draw and discuss flag registers of 8086 in brief? (3)

Figure of 8086 flag register – 1 Marks

8086 has 16 flag registers which is divided in to two parts

(a) Condition code (b) machine control flags

The description of each flag bits(O,D,I,T,S,Z,Ac,P,Cy) 2 Marks

2 Explain the physical address formation in 8086? (3)

The content of a segment register is shifted left bit-wise four times and to this results,

content of an offset register is added, to produce a 20 bit physical address. 2 Marks

Example 1 Marks

3 Mention the parameter passing mechanism of subroutines or procedures? (3)

Five parameter passing techniques (Using global declared variable, Using registers of CPU

architecture, Using memory locations, Using stack, Using PUBLIC and EXTRN) 3Marks

4 Compare shift and rotate instructions? (3)

Description of shift instruction 1 Marks

Description of rotate instruction 1 Marks, Difference between rotate and shift 1 Marks

Studoob.in - Where Learning is Entertainment

PART B

(Answer any two full questions, each carries 9 marks.)

5 a) Draw and discuss the read cycle timing diagram of 8086 in minimum mode? (4)

Read cycle timing diagram of 8086 in minimum mode. 4 Marks

b) Describe the maximum mode operation of 8086? (5)

Maximum mode operation of 8086:

Figure 2 Marks

Explanation 3 Marks

Studoob.in - Where Learning is Entertainment

6 a) Find square root of a two digit number. Assume that the number is a perfect

square? (5)

b) Specify major categories of instruction set supported by 8086 with suitable

examples? (4)

8 categories of instruction set of 8086/88. 3 Marks

One example for each category 1 Marks

Studoob.in - Where Learning is Entertainment

7 a) Draw and discuss the internal block diagram of 8086? (9)

Figure 4 Marks

Detailed description of each block 5 Marks

PART C

Answer all questions, each carries 3 marks.

8 Draw execution diagram of an interrupt service routine? (3)

Execution diagram of an Interrupt Service Routine 3 Marks

Studoob.in - Where Learning is Entertainment

9 Specify the role of non maskable interrupt? (3)

NMI (non maskable interrupt) has highest priority among the external interrupts. 1 Marks

Working of non maskble interrupt 2 Marks

10 Describe two different methods of interfacing I/O devices? (3)

Explanation of I/O mapped interfacing 1.5 Marks

Explanation of memory mapped I/O 1.5 Marks

11 What are the modes of operation of 8255? (3)

Two modes. I/O mode and BSR mode 1.5 Marks

Types of I/O mode 1.5 Marks

PART D

(Answer any two full questions, each carries 9 marks.)

12 a) Draw internal architecture of 8257 with brief description of register organization? (9)

Internal architecture of 8257 5 Marks

Brief description 4 Marks

13 a) Specify the significance of strobed bidirectional I/O mode of 8255? (3)

Salient feature and explanation of bidirectional I/O mode. 1.5 Marks

Control signals in mode 2 1.5 Marks

b) Mention different modes of operation of 8279? (6)

Studoob.in - Where Learning is Entertainment

14 a) Design an interface between 8086 CPU and two chips of 16KX8 EPROM and two

chips of 32KX8 RAM. Select starting address of EPROM suitable. The RAM address must start at

00000H. (9)

Address map for the above problem 4 Marks

Design of the interfacing static RAM memory 5 Marks

PART E

(Answer any four full questions, each carries 10 marks.)

15 Give brief description of memory and I/O addressing of 8051? (10)

Memory addressing, figure and explanation 7 Marks

I/O Interfacing 3 Marks

16 Draw the internal architecture of 8051 with brief description? (10)

Internal architecture 4 Marks

Brief Explanation 5 Marks

17 What are different addressing modes supported by 8051? (10)

8051 instruction set supports six addressing modes.

Explanation 7 Marks

Examples 3 Marks

18 With neat diagram, describe the interrupt structure of 8051? (10)

Explanation of five interrupts 10 Marks

19 Draw and explain the internal architecture of 8254/8253? (10)

Diagram 4 Marks

Explanation 6 Marks

Studoob.in - Where Learning is Entertainment

20 Write an assembly language program to count the number of 1's and 0's in a given 8-

bit number? (10)

Program 10 Marks

****

Studoob.in - Where Learning is Entertainment