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QUESTION BANK (DESCRIPTIVE)

Subject with Code: Microprocessors and Microcontrollers (23EC0414)

Course & Branch: B.Tech –ECE, CSE, CCC
Year & Semester: III - B.Tech. & I-Semester Regulation: R23

UNIT I
8086 ARCHITECTURE
PART-A (2 MARKS)

1 a) Define microprocessor. [L1][CO1][2M]

b) If a DS register holds the address of 1000H and data reference contains [L3][CO1][2M]
an address of 0031H, find the physical address?
c) What is the function of ALE signal in 8086? [L1][CO1][2M]
d) Define an interrupt vector and interrupt vector table. [L1][CO1][2M]
e) Describe the function of Stack Pointer in 8086. [L1][CO1][2M]
PART-B (10 MARKS)
2 a) List the main features of 8086 microprocessor. [L1][CO1][5M]
b) Describe about the 8086-microprocessor family. [L1][CO1][5M]
3 Draw the functional pin diagram of 8086 microprocessor and explain the [L1][CO1][10M]
function of each and every pin.
4 a) Explain in detail about the signals used in minimum mode of operation. [L2][CO1][5M]
b) Explain in detail about the signals used in maximum mode of operation. [L1][CO2][5M]
5 a) Draw the internal architecture of 8086 microprocessor. [L1][CO1][5M]
b) Discuss about the Execution unit of 8086 microprocessor. [L2][CO1][5M]
6 a) List and explain the general-purpose registers of 8086 microprocessor. [L1][CO1][5M]
b) Draw the flag register of the 8086 microprocessor and explain about each [L1][CO1][5M]
flag in detail.
7 a) Discuss about the Bus Interface Unit of 8086 microprocessor. [L2][CO1][5M]
b) Discuss about the importance of memory segmentation in 8086 [L2][CO1][5M]
microprocessors.
8 a) Explain about the following: [L1][CO1][5M]
i) Pointer and Index Registers ii) Segment Registers iii) Instruction
byte Queue
b) Define an Interrupt. Explain the series of actions that an 8086 [L1][CO1][5M]
microprocessor does in response to an when an interrupt.
9 Define the following terms. [L1][CO1][10M]
i) Segment Base ii) Instruction Pointer iii) Pipelining
iv) Instruction decoder v) Accumulator
10 a) Explain about maximum mode read cycle with suitable timing diagrams. [L2][CO1][5M]
b) Explain about minimum mode write cycle with suitable timing diagrams. [L2][CO1][5M]
11 a) Explain about maximum mode write cycle with suitable timing [L2][CO1][5M]
diagrams.
b) Explain about minimum mode read cycle with suitable timing diagrams. [L2][CO1][5M]
 UNIT II
8086 PROGRAMMING
PART-A (2 MARKS)

1 a) List the program developing steps in 8086? [L1][CO3][2M]

b) Give the instruction format used by 8086 microprocessor. [L2][CO3][2M]
c) Write a simple 8-bit addition program using general purpose register. [L3][CO3][2M]
d) What is the difference between SAR and SHR instructions? [L1][CO3][2M]
e) What are the assembly language program development tools? [L1][CO3][2M]
PART-B (10 MARKS)
2 a) Draw the flowchart symbols used to represent 8086 programming. [L1][CO3][5M]
b) What is an instruction? List various types of instructions in 8086. [L1][CO3][5M]
3 What are data copy instructions? Explain any five data copy instructions with [L1][CO3][10M]
examples.
4 Discuss about the following instructions with examples. [L2][CO3][10M]
(i) ADD
(ii) SBB
(iii) DEC
(iv) MUL
(v) NEG
5 a) Discuss about the following instructions with examples. [L2][CO3][5M]
(i) AND
(ii) OR
(iii) XOR
b) What is the difference between unconditional and conditional branch [L1][CO3][5M]
instructions? Explain with examples.
6 a) Discuss about string manipulation instructions. [L2][CO3][5M]
b) Explain any five flag manipulation instructions. [L2][CO3][5M]
7 a) Discuss about Processor control instructions of 8086. [L2][CO3][5M]
b) List Various conditional branch instructions with its descriptions. [L1][CO3][5M]
8 Define addressing modes? Explain various addressing modes of 8086 in [L1][CO3][10M]
detail.
9 a) Describe about assembler directives. [L1][CO3][5M]
b) Discuss about the following assembler directives. [L2][CO3][5M]
(i) DB
(ii) DW
(iii) DQ
(iv) DT
(v) ASSUME
10 a) Write an assembly language program to add and subtract two 16-bit numbers. [L3][CO3][5M]
b) Write an assembly language program to multiply two signed numbers using [L3][CO3][5M]
general purpose registers and explain by default where the result stores.
11 a) Write an assembly language program to find factorial of a given number. [L3][CO3][5M]
b) Write an assembly language program to find sum of the numbers 10H, 22H, [L3][CO3][5M]
3BH, 46H, and 7FH.
 UNIT-III
8086 INTERFACING

PART-A (2 MARKS)
1 a) Define a RAM and ROM. [L1][CO4][2M]
b) What is switch debouncing? [L1][CO4][2M]
c) Mention any two features of Intel 8251. [L1][CO4][2M]
d) Expand DMA and state its purpose. [L1][CO4][2M]
e) List the applications of a stepper motor. [L1][CO4][2M]
PART-B (10 MARKS)
2 Illustrate the interfacing of RAM and ROM with 8086 microprocessors [L3][CO4][10M]
with a neat diagram and address decoding.
3 a) List the features of Intel 8255 PPI. [L1][CO4][4M]
b) Discuss the architecture and operating modes of Intel 8255 [L2][CO4][6M]
Programmable Peripheral Interface.
4 a) Explain about the interfacing of switches with 8086 microprocessors. [L2][CO4][5M]
b) Differentiate between common cathode and common anode seven- [L4][CO4][5M]
segment displays.
5 Explain the working principle of a seven-segment display. Show how to [L2][CO4][10M]
interface it with 8086 through 8255.
6 Explain the applications of Software and Hardware interrupts in 8086 [L2][CO4][10M]
microprocessor.
7 With suitable diagram, explain the interfacing of Intel 8251 USART with [L2][CO4][10M]
8086 microprocessors. Explain how synchronous and asynchronous
modes are implemented.
8 a) Explain the working of Intel 8237a DMA controller and its interfacing [L2][CO4][6M]
with 8086 microprocessors.
b) State four features of Intel 8237a DMA controller [L1][CO4][4M]
9 Write an 8086-assembly language program to control the rotation of a [L1][CO4][10M]
stepper motor using 8255. Show the interfacing diagram and sequence of
excitation.
10 a) Discuss the interfacing techniques for Analog-to-Digital Converters with [L2][CO4][5M]
8086 microprocessors.
b) With suitable diagram explain the interfacing of Digital-to-Analog [L2][CO4][5M]
converter with 8086 microprocessors.
11 Why is Intel 8259 Programmable Interrupt Controller needed in 8086 [L4][CO4][10M]
systems? Explain its operation and priority modes
 UNIT – IV
MICROCONTROLLER
PART-A (2 MARKS)
1 a) List the features of 8051 microcontroller. [L1][CO2][2M]
b) List out the special function registers in 80851 microcontrollers. [L1][CO2][2M]
c) Discuss about Data Pointer. [L2][CO2][2M]
d) Explain about the function of a program counter. [L2][CO2][2M]
e) Define Addressing Mode. List the different types of addressing modes. [L1][CO3][2M]

PART-B (10 MARKS)

2 Draw the internal architecture of 8051 microcontroller and explain the [L1][CO2][10M]
function of each block present in it.
3 a) Describe the internal RAM structure in the 8051 microcontrollers. [L1][CO2][5M]
b) Review the PSW Register in 8051 microcontrollers. [L2][CO2][5M]
4 Draw and explain the pin diagram of 8051 microcontroller. [L1][CO2][10M]
5 a) Discuss about various functions of 8051 ports. [L2][CO2][5M]
b) Analyze the functionality of I/O pins ports and circuits in 8051 [L4][CO2][5M]
microcontrollers.
6 a) Discuss any 3 logical operation instructions of 8051 microcontroller. [L2][CO3][5M]
b) Give result for the following instructions with A=32, R1=77 [L2][CO3][5M]
A) ANL A,R1 B) CPL A C) XRL A,R1
7 a) Discuss RR , RLC, and SWAP instructions with example. [L2][CO3][5M]
b) Explain ADD, SUBB, DIV instructions of 8051 microcontroller with [L2][CO3][5M]
example.
8 a) Differentiate between Jump and Call instructions. [L4][CO3][5M]
b) Explain the following instructions [L2][CO3][5M]
A) PUSH B) POP C) XCHD
9 Describe the different types of addressing modes supported by 8051 with [L2][CO3][10M]
suitable examples.
10 a) Write an ALP to place the number 34H in register R5, R6, and R7 using [L3][CO3][5M]
immediate and register addressing modes.
b) Write an ALP to put the number 8DH in RAM locations 3050H and [L3][CO3][5M]
3054H.
11 a) Develop an assembly program of 8051 microcontroller for addition of two [L3][CO3][5M]
8-bit numbers in internal memory location 30H and 40H and store the
result in a memory location 50H.
b) Give three different ways to clear the contents of the ‘A’ register. [L2][CO2][5M]
 UNIT V
INTERFACING MICROCONTROLLER
PART-A (2 MARKS)

1 a) Define TMOD register in 8051. [L1[[CO2][2M]

b) What is the difference between Timer and Counter in 8051? [L1][CO2][2M]
c) What is an Interrupt Service Routine (ISR)? [L1][CO2][2M]
d) Define key debouncing. [L1][CO4][2M]
e) Define a step angle in stepper motor. [L1][CO4][2M]
PART-B (10 MARKS)
2 Explain the different modes of 8051 timers with neat diagrams. Write an [L2][CO3][10M]
assembly language program to generate a 1ms delay using Timer 1.
3 Describe the working of the 8051 serial communication system. How is [L2][CO3][10M]
the baud rate generated using Timer 1? Write an example program for
transmitting "HELLO".
4 Discuss the types of interrupts in the 8051 microcontrollers. Explain the [L2][CO2][10M]
interrupt vector table and the role of IE and IP registers with an example
program.
5 Explain the interfacing of a 16×2 LCD with the 8051 microcontroller. [L2][CO6][10M]
Write the steps and initialization commands required to display
`"WELCOME"`.
6 How is a 4×4 matrix keyboard interfaced with the 8051? Explain the [L2][CO6][10M]
row–column scanning technique with an example program to detect a
key press.
7 Explain the interfacing of an ADC0809 with the 8051 microcontrollers. [L2][CO6][10M]
Draw the block diagram and write a program to read analog voltage
values.
8 Describe how DAC0808 is interfaced with 8051. Explain the procedure [L2][CO6][10M]
to generate a triangular waveform using DAC. Also, mention how a
temperature sensor (LM35) can be interfaced.
9 a) Explain in detail how 8051 interfaces with external program and data [L2][CO4][5M]
memory.
b) State the function of ALE and PSEN pins in external memory interfacing. [L1][CO6][5M]
10 Explain the interfacing of a stepper motor with 8051 using ULN2003 [L2][CO6][10M]
driver IC. Write the sequence of operations required to rotate the motor
clockwise and anticlockwise.
11 a) Compare PIC Microcontroller and ARM Processors. [L5][CO5][5M]
b) Discuss the advantages and disadvantages of Microprocessors compared [L2][CO5][5M]
to Microcontrollers.