QUESTION BANK

MICROPROCESSORS

Faculty name: Mrs.Rashmi .R.Deshpande

UNIT -1 Introduction, Microprocessor Architecture Question SL.NO 1. What is microprocessor? Explain how data, address and control buses interconnect various system components. 2. Explain the program model visible register organization of 8086 microprocessor 3. What is conventional memory? Explain segments and offsets. List default segment and offset register pairs. 4. Describe the memory map of a PC system, with a neat diagram. 5. Explain the flags of8086 processor using suitable examples. 6. Draw and explain the programming model of the 8086 through the CORE-2 microprocessor including the 64-bit extensions. 7. Describe the overview of the various 80X86 and Pentium family members 8 Draw the block diagram of computer system and explain the purpose of each block. 9. Describe the function of microprocessor and its basic operation in detail 10. Define the contents of memory system in personal computer and explain each section of memory. 11. Explain RISC and CISC processors. 12. Differentiate with conceptual view between the processor 80486, Pentium pro, P3, P4, and core 2 microprocessor. 13. Explain the block diagram of a microprocessor based on computer based system. 14. Explain with a neat block diagram address, data and control bus structure of a computer system 15. Write a short note on Pentium Microprocessors. 16. Explain conditional flags in Microprocessors. 17. Explain in detail segment registers in Microprocessors? 18. Explain the four fields in a Microprocessor format? 19. Draw the physical memory system diagram for intel Pentium processors. 20. Discuss the functions of segment registers of 8086 with examples. Give

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some advantages of memory segmentation What is pipelining? How it is achieved in 8086?

UNIT-2 MICROPROCESSOR ARCHITECTURE-2, ADDRESSING MODES: SL.NO Question 1. Explain the descriptors of 80286 and 80386 microprocessors. Also explain prog invisible registers within 80286 microprocessor. 2. Explain with examples the following addressing modes: i) Scaled –indexed addressing mode. ii) RIP relative addressing mode. iii) Relative prog memory addressing mode. 3. What is stack? What is the use of stack memory? Explain the execution of push and pop instructions. 4. What are the advantages of memory paging? Illustrate the concept of paging with neat diagram. 5. Discuss the following addressing modes with examples: 1) direct 2)register indirect 3)base plus index 4)immediate 5) scaled indexed. 6. Explain page directory and page table. 7. Explain the control register structure of the microprocessor. 8. Briefly explain program invisible register with a neat diagram. 9. Explain register addressing, immediate addressing and direct data addressing modes with examples. 10. Explain register indirect addressing, base+index addressing, register relative addressing with examples. 11. Explain with examples base relative plus index addressing. 12. Explain program memory addressing modes with an example. 13. Write a short note on Stack Memory addressing mode. 14. Describe the format of MOV instruction (16-bit instruction mode) in detail. 15. Write the Opcode corresponding to MOV DL, [DI]. 16. What is the difference between an LEA SI, NUMB and a MOV SI,OFFSET NUMB instruction? 17. Explain the purpose of Direction flag and explain LODS, STOS instructions with examples. 18. Give an example and explain the concept of a ‘segment override prefix’. 19. Write a program using full segment definitions that reads a key and display it. 20. Explain with example the assembler directive ASSUME and ORG. 21. 22.

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Explain how virtual address is translated into physical address with a 8* neat diagram. Identify the addressing modes of the following instructions and explain 6*

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them briefly:i)MOV WORD PTR [SI],20H ii) MOV ES:[1000H],10H iii) MOV CX,NUM[BX+DI] Explain Flat mode memory model with a neat diagram.

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UNIT 3 PROGRAMMING-1 SL.NO Question 1. Describe the following instructions with suitable examples a) PUSH b) mul c) IN d) aaa 2. Write an ALP using 8086 instructions to generate and add the first l0 even numbers and save the numbers and result in memory location Num and Sum. 3. Bring out the importance of XLAT instruction using a suitable program. 4. Write bubble sort program using 8086 assembly instructing. 5. Explain the following instructions with an example for each : a) LEA b) XCHG c)XLAT D) div e)AAA 6. What do you mean by segment over ride prefix? Explain the following assembler directives :1 )assume 2) SMALL 3) proc 4)EQU 5)LOCAL 7. Explain MOV instruction template in 16 bit instruction mode. 8. Explain MOV instruction template in 32 bit instruction mode. 9. Generate the opcodes for the following mov instructions and explain A) MOV bp,sp B) Mov dl,[di] C) Mov [1000h],di D) MOV [BP],DL E) MOV WORD PTR[BX+1000H],1234H 10. Explain with a neat diagram scaled index byte and REX prefix for 64 bit operations. 11. Explain the effect of push ax instruction on ESP and stack memory locations. 12. With a neat diagram the effect of pop bx instruction showing how data are removed from the stack. 13. Explain LEA, LDS, LES instructions with examples. 14. Explain with neat diagram the instruction LDS bx,[di] 15. Explain the importance of direction flag in string data transfer instructions. 16. Explain the string instructions LODS, STOS, MOVS with examples. 17. Explain the operation of LODSW instruction if ds=1000h ,d=0,11000h=32 and 11001h=A0. 18. Explain 1) proc and endp 2) data definition directives 3)ORG 19. Explain arithmetic instructions with examples. 20. Explain signed and unsigned multiplication division instructions with

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examples. Explain imul cx, dx, 12h. 6 Write an ALP using 8086 instructions to search a number placed in a 6* location NUM, in an array of ten numbers placed at location ARRAY. Give suitable messages. Give the status of all status flag bits after the addition of 30A2H with 4* F01CH

UNIT 4 PROGRAMMING-2 SL.NO Question 1. Write an ALP using 8086 instructions to count the numbers of zeros in a given 8 bit number and store the result in memory location 'Res'. 2. Explain the following assembler directives: i) Assume; ii) Proc; iii) Ends; iv) DB. 3. Briefly explain any four bit test instructions. 4. With format explain rotate instructions .Give examples to rotate right by 1-bit and rotate left by 5 bits. 5. Discuss with examples unconditional and conditional branching instructions. 6. What is procedure? Explain the sequence of operation that takes place when a procedure is called and returned. 7. Explain m/c control instructions with examples. 8. Explain bit manipulation instructions with examples. 9. Explain DAA and DAS instructions with examples. 10. Explain with examples AAA,AAD,AAM and AAS instructions. 11. With format explain shift instruction.Why count value is stored in cl register for shift instructions. 12. Explain with a program scas ,cmps instruction. 13. Describe the format of JMP instructions for short,near and far jump. 14. Describe LOOP instruction and various types of loops. 15. Write a program using while loop structure to read a character string from the keyboard and to display it again. 16. Describe near and far procedure with call and return instructions. 17. Explain type 0 to type 5 interrupt in detail. 18. What is interrupt vector? How an address is generated for various types of interrupt. 19. Explain NOP, WAIT AND halt instructions. 20. Describe ENTER, LEAVE, ESC, BOUND instructions. 21. Write a sequence of instructions that sets (1) the rightmost 4 bits of AX; clears(0) the leftmost 3bits of AX; and inverts bits 7,8,9 of AX.

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Explain the operation of DAA and show the result of addition of 1234h&3099h. Describe the difference between the AND and TEST instructions Explain XADD instruction with an example. Explain the difference between SAR and SHR instructions with examples Differentiate between procedure and macro.

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Write an ALP to reverse a four digit number.

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UNIT-5 Programming 3 SL.NO Question 1. Explain public and EXTRN directives of assembler and write alp to read data through keyboard using external procedure and save the keycode in public data segment. 2. Write a C program that uses –asm function to display strings on output device. 3. Explain with neat diagram clock generator IC8284. 4. Distinguish between the 16 bit and 32 bit versions of c/c++ when using the inline assembler. 5. Write a mixed language program that converts binary to ASCII. 6. Write a mixed language module to realize macro to read a character from keyboard. 7. Explain with an example linking of assembly language with visual c++. 8. Write an alp that displays one word per line. 9. Write a program that illustrates assembly language procedure that displays C language character strings. 10. Write a program that functions as a simple calculator to perform basic arithmetic operations. 11. Write a program that displays any number in all number bases between base 2 and base 16. 12. Write a program to convert binary number to ascii number. 13. What is in line assembly? Explain its need 14. State C.language elements that can be used in arm block. 15. Explain the basic rules of using assembly language with C/C++ for 16 bit DOS applications. UNIT-6 Hardware Specifications, Memory-Interface 1

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SL.NO Question 1. Explain in brief the functions of 8086 pins 1) MN/MX(active low) 2)ALE 3)NMI 4) Ready 5) RESET 6) BHE(active low) 2. Describe DE multiplexing of multiplexed AD bus with neat diagram. 3. With a neat timing diagram, explain memory read cycle. 4. Explain the following functions of the 8086 microprocessor 1)RESET 2)READY 3)ALE 4)LOCK(active low) 5. With diagram explain the RESET section of 8284 clock generator.Also indicate how clk and RESET are connected to 8088 microprocessor. 6. Using timing diagram explain the i/o write bus cycle in 8086 microprocessor. 7. Bring out the differences between 8086 and 8088 microprocessors. 8. Explain the hardware interrupt inputs NMI, INTR and INTA (active low signal) using timing diagram. 9. Draw the internal block diagram of 8284A clock generator and explain its operation. 10. Write short note on Simplified read and write bus cycle, Address decoding in memory interface 11. Write a short note on max and min mode of operation of 8086? 12. With a functional block schematic, explain the pin configuration and functions of each signal in the clock generator 8284? 13. Describe the minimum and maximum mode of 8086 with details of each pins. 14. Explain the operation of 8284a clock generator. 15. Write a short note on Demultiplexing the address bus of 8088 and 8086 with neat diagram.

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UNIT-7 Memory-Interface 2,I/0 interface -1 SL.NO Question 1. Interface 512 kb RAM to 8088 MP using 64kb RAM using 3:8 decoder with starting address of memory as 80000h.Clearly mention decoding logic and memory map. 2. Explain memory bank selection in 8086 and mention the number of memory bank in 80x86 MPs. 3. Differentiate between memory mapped I/0 and I/O mapped I/0(isolated). 4. Explain how 74LS138 decodes 2732 EPROMS for 32K x 8 section of memory. Assume the starting address is 40000h.Give the detailed memory map. 5. What is flash memory? Explain how a flash memory is interfaced to 8086MP. 6. Explain 74138 decoder configurations to enable ports at address E8H to

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EFH. What is an I/O interface? Why do we need an I/O Interface? Explain the differences between two different methods of interfacing I/O to the microprocessor? What is Handshaking? How to synchronise I/O with Microprocessor using basic input and output devices? Explain Memory Pin Connections with a diagram of Pseudo memory component Write short note on ROM memory Bring out the differences between SRAM and DRAM. Why should we decode memory? Explain with Simple NAND gate decoder What is an address decoding ? How a port decodes A) 8 bit port B) 16 bit i/o port C) 8& 16 bit port D) 32 Bit i/o port Explain the I/O port address decoding. Explain the error correction scheme. List various memory devices. What is memory address decoding?Design a memory system for 8086 for the following specifications.i)32K bytes EPROM using 16K bytes devices. ii) 64 K bytes SRAM using 16K bytes devices. Draw the memory map.

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UNIT-8 I/0 interface -2, Interrupts, and DMA SL.NO Question 1. Write an 8086 ALP to read a byte of data from port A and port B .Add the data and save the result in a memory location. 2. Explain the command word format of 82c55 in mode-0.Write the control word format to initialize to set PC3 and reset PC7. 3. With internal block diagram, explain 8254 PIT. Give any two applications of the 8254. 4. Explain interrupt vector table in brief. 5. Interface 8 digit seven segment LED display to 8088 mp through 8255 PPI.Write initialization sequence for 8255 with all the port as output ports in mode 0 and address of device is FF00H. 6. Explain control word format for IC 8254 and interface IC to 8086 mp to generate square wave of 100khz using counter 0 to write an ALP for the same.Assume clock frequency of 10Mhz. 7. What is PPI? Write the command word byte of the command reg in the 82C55PPI? 8 How to interface an 8255 to 80386 Microprocessor? 9 Write the procedure for a LCD display interfaced to the 82c55 for the conditions 10. Explain the internal structure and timing diagram of

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a) mode 1 strobed input operation b) mode1 strobed o/p operation c) Mode 2 operation of 82c55. Write the internal structure of 8254 with six different modes of operation? What is an interrupt? Differentiate between hardware and software interrupts Explain DMA operation with HOLD and HDLA Timing diagram Describe Interrupt Vector Table for Mp .Explain type 0 to type 5 Interrupt What are the sources of interrupts? Briefly explain the steps taken by the processor to execute an interrupt instruction. Briefly explain the control word format of 8255 in I/O mode and BSR mode. Give the control word format to program Port A and Port C lower as input and Port B and Port C upper as output parts in mode 0. Write an ALP using 8086 instructions to read a byte of data from Port A and Display its parity status as 00H or FFH for odd and even parity respectively on Port B

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