MPI Mid Exam Questions

MPI Ist Mid Exam Questions

SWARNANDHRA INSTITUTE OF ENGINEERING AND TECHNOLOGY

SEETHARAMPURAM,

NARSAPUR-534280

Subject: Microprocessors and Interfacing

IIIrd ECE

1st mid Question Paper

Unit 1

1.a) With a neat block diagram explain the architecture of 8086 processor. (15)b) Explain why memory is segmented in 8086 and also explain how memory is

addressed using segmentation. (5)

2.a) Compare the flag registers of 8086 and 8085 and explain each flag in detail. (10)b) Explain the Arithmetic instruction of the 8086 processor. (10)

3.a) Explain the functioning of the following registers of 8086 Microprocessor (12)

I. General Purpose Register.II. Segment Register.

III. Index and Pointer Register.IV. Flag Register.

b) Discuss briefly about pre-fetch queue in 8086. (8)

4.A. The Register contents of 8086 are given below. (10)CS=5000H, DS=6000H, SS=A000H, ES=B000H, SI=2000H, DI=3000H, BP=1002H, SP=0002H, AX= 0000H, BX=5200H, CX=2000H, DX=2000HCalculate the Effective Address and physical address of the following instructions.

a) IMUL AX,[BP+BX-8D]b) SBB AL,ES:[SI+5D]c) AND AH,[SI+42D]d) CMP DX, [SI]e) XOR DH, [DI+8D]

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f) DIV AX, [SI+2]

B. Explain the following assembler directives, (10)a) ASSUMEb) ENDSc) EVEN d) OFFSETe) PUBLICf) EXTERN

5.a. Differentiate between Procedures and Macros using certain examples. (10)b. What are MACROs? How do you pass parameters to MACROs? (10)

6. (a) Explain the meaning of the following 8086 instructions 2-36 aio (10)I. MOV [3845H], BX

II. ADD AX, [SI]III. MOV BX, 2956HIV. ADC AX, BX

(b) Describe the following Addressing modes with some examples. (10)I. Indexed Addressing with Displacement.

II. I/O port Addressing.

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Unit II

1.a) Write an ALP to subtract two 32-Bit Numbers. (10)b) Develop an 8086 assembly language program for performing division on 32-bit word

by 16-bit Word. 3-25 aio (10)

2.a) Write an ALP in 8086 to ADD two 32-digit numbers (10)b) Write an ALP in 8086 to Divide a 16bit number by a 16-bit number (10)

3.a) Using REPEAT – UNTIL construct, Develop a sequence of 8086 instructions that read

a character from the key board with echo and display the character. 3-3 aio (10)b) Write an ALP for finding the average on n numbers. 3-24 aio similar (10)

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UNIT III

1. What are the modes in which the 8086 can be used? How many lines are there in the multiplexed bus of 8086? Give the pin diagram separately for each mode of operation.

(20)

2.a) Discuss the Minimum mode memory control signals of 8086. (10)b) Explain the write cycle operation of the microprocessor with a neat timing diagram

in Maximum Mode. (10)3.

a. Explain the bus structure of 8086 system. (10)b. Explain the fundamental concepts of DRAM controller. (10)

4.a. Explain the DRAM interfacing. (10)b. Interfacing two 4K x 8 EPROMs and two 4K x 8 RAM chips with 8086. Select suitable

memory map (10)

5. (a) Explain how Static RAMs are interfaced to 8086. Give necessary interfacing diagram assuming appropriate signals and memory size. (10)(b) Explain the need of DMA. Discuss in detail about DMA data transfer method. (10)

6. (a) What are the registers available in 8257? What are their functions? (10)(b) Explain the function of following signals of 8257. (10)

I. HLDAII. AEN

III. MARKIV. MEMR

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UNIT IV

1. Describe the Mode 0, Mode 1 and Mode 2 I/O operations of the 8255 PPI. (20)Interface a 4*4 key board with 8086 using 8255 and write an ALP for detecting the key closure and return the key code in AL. The Debouncing period for a key is 10ms. Use a software key debouncing technique. DEBOUNCING is available 1ms delay routine.

2.a) Draw the internal block diagram of 8255 and explain its working, and Explain about

the transfer modes of 8255 (12)b) Explain how a keyboard is interfaced to 8086 through 8255. Draw the necessary

interfacing circuits? (8)

3.a) Interface 16-bit 8255 ports with 8086. The Address of port A is 0FH. (10)b) Distinguish between BSR Control word and Mode Set Control word of 8255. (10)

4. Interface an 8255 with 8086 at 80H as an I/O address of Port A. Interfacing five segment displays with the 8255. Write a sequence of instructions to display 1, 2, 3, 4 and 5 over the five displays continuously as per their positions starting with 1 at the least significant position (20)

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MPI Mid Exam Questions