DHANALAKSHMI COLLEGE OF ENGINEERING
DEPARTMENT OF INFORMATION TECHNOLOGY
CS2252-MICROPROCESSOR AND MICROCONTROLLER
SEMESTER-IV
YEAR: II
UNIT I
THE 8085 AND 8086 MICROPROCESSOR
PART A
1. What is Microprocessor? (AU-Nov’06)
A microprocessor is a multipurpose, programmable logic device that reads
binary instructions from a storage device called memory or accepts binary data as
input and processes data according to those instructions and provides result as
output.
2. What is accumulator?
Accumulator or A register is an 8-bit register used for arithmetic, logic, I/O and
load/store operations.
3. What are the flags are used in 8085? (AU-Nov’06)
Flag is an 8-bit register containing 5 1-bit flags: They are,
Sign - set if the most significant bit of the result is set.
Zero - set if the result is zero.
Auxiliary carry - set if there was a carry out from bit 3 to bit 4 of the result.
Parity - set if the parity (the number of set bits in the result) is even.
Carry -set if there was a carry during addition, or borrow during
subtraction/comparison.
4. What is the use of general purpose registers in 8085 and specify their function?
(i) 8-bit B and 8-bit C registers can be used as one 16-bit BC register pair. When used
as a pair the C register contains low-order byte. Some instructions may use BC
register as a data pointer.
(ii) 8-bit D and 8-bit E registers can be used as one 16-bit DE register pair. When used
as a pair the E register contains low-order byte. Some instructions may use DE
register as a data pointer.
(iii) 8-bit H and 8-bit L registers can be used as one 16-bit HL register pair. When used
as a pair the L register contains low-order byte. HL register usually contains a data
pointer used to reference memory addresses.
5. What is a Stack pointer?
Stack pointer is a 16 bit register. This register is always incremented or
decremented by 2. It is used as a memory pointer. The beginning of the stack is
defined by loading a 16-bit address in the stack pointer.
6. What is the function of program counter?
The function of the program counter is to point the memory address
from which the next byte is to be fetched. When a byte is being fetched the
PC is incremented by one to point to the next memory locations.
7. What are the type of registers? (AU-May’05)
Registers are divided into three major types. They are,
(i) Single purpose register
(ii) Special purpose register
(iii) General purpose registers.
8. Define opcode and operand.
Opcode is the part of an instruction that identifies a specific operation.
Operand is a part of an instruction that represents a value on which the
instruction acts.
9. What is PSW?
PSW-Program Status Word. The flag register and accumulator together is called
PSW. Flag register is high order register and A is low order register.
10. What is function of ALE signal? (AU-May’08)
The ALE is a signal used to demultiplex the address and lines , using an
external latch. It is used to enable the external latch.
11. Mention the types of 8085 instruction set depending the function.
The types of 8085 instruction set depending the function are:
(i) Data transfer instruction
(ii) Arithmetic instruction
(iii) logical instruction
(iv) Branch instruction
(v) Machine control instruction
12. Mention the types of 8085 instruction set depending the word length.
The types of 8085 instruction set depending the word length are:
(i) One byte instruction
(ii) Two bye instruction
(iii) Three byte instruction.
13. What are the different types of addressing modes used in 8085?(AU-May’08)
The different types of addressing modes used in 8085 are:
(i) Immediate addressing
(ii) Direct addressing
(iii) Indirect addressing
(iv) Register addressing
(v) Implicit addressing
14. List some data transfer instructions.
The data transfer instructions move data between registers or between memory and
registers are:
MOV
Move
MVI
Move Immediate
LDA
Load Accumulator Directly from Memory
STA
Store Accumulator Directly in Memory
LHLD
Load H & L Registers Directly from Memory
SHLD
Store H & L Registers Directly in Memory
15. List some logical instructions.
Some of the logical instructions are:
ANA
Logical AND with Accumulator
ANI
Logical AND with Accumulator Using Immediate Data
ORA
Logical OR with Accumulator
OR
Logical OR with Accumulator Using Immediate Data
XRA
Exclusive Logical OR with Accumulator
XRI
Exclusive OR Using Immediate Data
16. Give the different compare instructions. (AU-May’05)
The Compare instructions compare the content of an 8-bit value with the contents
of the accumulator;
CMP
Compare
CPI
Compare Using Immediate Data
17. List some rotate instructions.
The rotate instructions shift the contents of the accumulator one bit position to the
left or right:
RLC
Rotate accumulator Left
RRC
Rotate accumulator Right
RAL
Rotate Left through Carry
RAR
Rotate Right through Carry
18. List any three unconditional branch instruction. (AU-Nov’07)
The unconditional branching instructions are as follows:
JMP
Jump
CALL
Call
RET
Return
19. What is conditional branching instructions?
Conditional branching instructions is to examine the status of one of four
condition flags to determine whether the specified branch is to be executed.
20. What are the I/O instructions used in 8085?
The I/0 instructions used in 8085 are as follows:
IN
Initiate Input Operation
OUT
Initiate Output Operation
21. What are the machine control instructions used in 8085? (AU-May’06)
The Machine Control instructions used in 8085 are as follows:
EI
DI
HLT
NOP
Enable Interrupt System
Disable Interrupt System
Halt
No Operation
22. What is an immediate addressing mode? Give example.
An immediate addressing mode is the mode in which the data
is specified in the instruction itself. The data will be part of the program instruction.
Example: MVI A, 06
22. What is implicit addressing mode?
Implicit addressing mode is the mode in which the instruction operates
on a data available in a predetermined register.
Example: CMA
23. What is TRAP?
Trap is the non-maskable interrupt. When this interrupt is received
the processor saves the contents of the PC register into stack and branches to
24h (hexadecimal) address.
24. List some maskable interrupt.
Some maskable interrupts are :
INTR
RST 5.5
RST 6.5
RST 7.5
25. List the software and hardware interrupts of 8085.
Software interrupts: RST 0, RST 1, RST 2, RST 3, RST 4, RST 5, RST 6, RST 07
Hardware interrupts: TRAP, RST7.5, RST6.5, RST 5.5, INTR
26. List out the function of Accumulator.(AU-NOV’08)
The functions of accumulator are:
(i) It is an integral part of ALU.
(ii) It holds one of the data to be processed by ALU.
(iii) It temporarily stores the result of an operation performed by ALU.
27. What is the use of ALE signal in 8085? (AU-JUN’06) (AU-NOV’07)
The ALE (Address Latch Enable) is a signal used to demultiplex
the address and data lines, using an external latch.
It is used to enable the external latch.
28. Give the format of flag register in 8085? (AU-JUN’06)
The format of flag register in 8085 is given as:
D7
D6
S
Z
D5
D4
AC
S - Sign flag
Z - Zero flag
AC - Auxiliary carry flag
P - Parity flag
CY - Carry flag
D3
D2
D1
D0
P
CY
29. How address and data lines are demultiplexed in 8085? (AU-MAY’07)
30. What is the function performed by SIM instruction in 8085? (AU-MAY’07)
The function performed by SIM instruction in 8085 is:
1. To set mask for RST 7.5, 6.5, and 5.5 interrupts. Bit D3 is a control bit
and should be 1 for bits D0 D1 and D2 to be effective.
2. To reset RST 7.5 flip-flop. If D4 is 1, RST 7.5 is reset.
3. To implement serial I/O. Bits D7 and D6 of the accumulator are
used for serial I/O and do not affect the interrupts.
31. Give the significance of SIM and RIM instruction available in 8085.
(AU-NOV’06)
32. What do you mean by Assembler? (AU-NOV’08)
Assembler is a program that translates the mnemonics
entered by the ASCII keyboard into the corresponding binary
machine codes of the microprocessor.
33. What are the functions of the RST 6.5 and ALE signals of 8085?
(AU-NOV’09)
34. What do you mean by Non Maskable Interrupt? (AU-NOV’08)
35. List the interrupt signals present in 8085 processor in the priority order.
(AU-APR’08)
The interrupts signals present in 8085 processor in the priority order
is given by:
1. TRAP
2. RST 7.5
3. RST 6.5
4. RST 5.5
5. INTR
36. What is a Program counter? (AU-NOV’07)
The program counter is a 16-bit address. To execute a program the starting
address of the program is loaded in program counter. The PC sends out an
address to fetch a byte of instruction from memory and increments its
content automatically.
37. Define indirect addressing mode and give an example. (AU-NOV’07)
38. What is the use of ALE signal? (AU-NOV’07)
The ALE (Address Latch Enable) is a signal used to demultiplex
the address and data lines, using an external latch. It is used to enable
the external latch.
39. List any four unconditional branch instructions. (AU-NOV’07)
40. What is the use of HOLD and HLDA signals? (AU-NOV’07)
HOLD and HLDA acknowledge signals are used for the Direct Memory
Access (DMA) type of data transfer.
41. What is the function of HOLD and HLDA? (AU-APR’08)
The function of HOLD and HLDA is given by:
(i) The DMA controller places a high on HOLD pin in order to take
control of the system bus.
(ii) The HOLD request is acknowledged by the 8085 by driving all its
tristated pins to high impedance state and asserting HLDA signal high.
PART B
1. Explain the architecture of 8085 microprocessor with neat diagram
(AU-NOV’06) (AU- MAY’07) (AU-JUN’07) (AU-NOV’07) (AU-APR’08) (AU-NOV’08)
(AU-NOV’09)
2. Explain the types of interrupts in detail. (AU-NOV’09)
3. Explain the types of instruction set of 8085 depending the word length with
example. (AU- MAY’07)
4. Explain the types of instruction set of 8085? (AU-NOV’07) (AU-NOV’08)
5. Explain the different types of addressing modes of 8085. (AU- MAY’07)
6. Write notes on status flag. (6) (AU-JUN’07)
7. Explain the 8085 based microcomputer system
8. Write an ALP to add two 2- digit BCD numbers. (AU-JUN’07) (8)
9. Describe the signals present in 8085. (AU-APR’08) (8)
10. Write a program to convert 8 bit binary number to BCD. (8)
11. Write a program for block transfer of data bytes. (8)
12. Write a program to add a series of 10 numbers starting from memory location
3000H onwards. (8)
13. Write an ALP to add two 8 bit numbers. (6) (AU- NOV’06)
14. How the instruction set of 8085 classified is based on their functions and word
length? Give example.(10) (AU- NOV’06)
16. List out the Mask able and Non – Mask able interrupts available in an
8085 processor. (AU-Nov’06)
(4)
18. Explain the various logical and arithmetic instructions available in
8085 microprocessor. (AU-MAY’07) (10)
19. Explain the function of various flags of 8085 microprocessor.
(AU-MAY’07) (10)
20. Differentiate between I/O mapped I/O and memory mapped I/O.
(AU-MAY’07)
(6)
21. Write an 8085 assembly language program to convert 8 bit binary to
ASCII code. (AU-MAY’07)
(10)
22. Write an 8085 program to subtract one 4-digit decimal number
from another. (AU-NOV,09) (6)
23. Write an 8085 program to find the largest of a set of n
8-bit numbers. (AU-NOV,09) (6)
24. Write a program to convert Binary number to BCD number
and explain. (AU-NOV’08) (8)
25. Write BCD and Binary code Conversion Program and explain.
(AU-NOV’08) (8)
26. Describe an 8085 interrupt process. (AU-NOV’07) (8)
27. Write short notes on RST (RESTART) instructions. (AU-NOV’07) (8)
28. Write down the comparison of:
(AU-NOV’07)
(i) Memory mapped I/O and peripheral I/O. (8)
(ii) CALL, RET and PUSH, POP instructions. (8)
29. Sixteen bytes of data are stored in memory locations at XX 50 H to XX 5F H.
Write a program to transfer the entire block of data to new memory
locations starting at XX 70 H. Using 8085 instructions. (AU-NOV’07) (8)
30. Registers BC contain 8538 H and registers DE contain 62A5 H.
Write instructions to subtract the contents of DE from the contents of
BC and place the result in BC. (AU-NOV’07) (8)
31. Discuss in detail the classification of 8085 Instruction set. Explain the
instructions under each category. Also explain the classification based on
the word size with relevant examples. (AU-NOV’07)
(16)
32. Draw and explain about a single board microcomputer system based on
8085.
(AU-NOV’07)
(8)
33. Write a program to check a set of six signed numbers and add the
positive numbers. (AU-NOV’07)
(8)
34. Draw the timing diagram for SHLD 16-bit address. (AU-APR’08)
(8)
35. Write an 8085 ALP to convert hexadecimal value to decimal value.
(AU-APR’08) (8)
36. Explain the pin definition of 8085 (AU-JUN’06) (8)
37. Explain the instruction set of 8085 in detail with one example in
each group. (AU-JUN’07) (10)
38. Write notes on status flag. (AU-JUN’07) (6)
39. Write a program to perform the following functional functions and
verify the output steps:
(AU-NOV’07)
(16)
(i) Load the number 8B H in register D.
(ii) Load the number 6F H in register C.
(iii) Increment the contents of register C by one.
(iv) Add the contents of register C and D display the sum at output port1.
40. Write a program to convert 8 bit binary number to BCD. (AU-APR’08) (8)
41. Write a program for block transfer of data bytes. (AU-APR’08)
(8)
42. Write a program to add a series of 10 numbers stored from location
3000H onwards. (AU-APR’08) (8)
43. List out the similarities between CALL-RET and PUSH_POP instructions.
(AU-JUN’07) (2)
44. Sketch the schematic to generate separate read/write control signals for memory
and I/O related signals in 8085.(AU-NOV’07) (2)
45. Calculate the execution time of an instruction MVI A, 82 H in 8085 runs
at 2 MHz. (AU-NOV’07) (2)
46. Write an assembly language program of 8085 to add two numbers stored in
memory locations 4040 H and 4041 H. Save the sum in location 4042 H.
(AU-NOV’07) (2)
47. Assume register B holds 93 H and the accumulator holds 15 H. Illustrate the
results of the instructions ORA B, XRA B and CMA. (AU-NOV’07) (2)
48. Mention some of the applications of Rotate Instructions. (AU-NOV’07) (2)
49. List the different flags affected by the arithmetic and logic operations.
(AU-NOV’07) (2)
50. Draw the contents of the stack and the registers after a PUSH instruction.
(AU-NOV’07) (2)
51. Give the sequence of operation that takes place during the execution of
call instruction. (AU-APR’08) (2)
52. When the READY signal of 8085 microprocessors is sampled by the processor?
(AU-JUN’07) (2)
53. Write an 8085 assembly language program to multiply two 8-bit numbers.
(AU-NOV’09) (2)
54. Let accumulator content is 9AH and CY = 1. What will be content of CY after
RRC instruction is executed. (AU-APR’08) (2)
UNIT II
8086 SOFTWARE ASPECTS
PART A
1. What are the modes in which 8086 can operate? (AU-JUN’06) (AU-JUN’07)
The modes in which 8086 can operate are:
Minimum (uniprocessor) mode and maximum (multiprocessor) mode.
2. What is the data and address size in 8086?
The data size in 8086 can be either 8-bit or 16-bit.
The address size in 8086 uses 20-bit address to access memory and
16 bit address to access I/O devices.
3. Explain the function of M/IO in 8086.
The function of M/IO in 8086 are:
(i) The signal M/IO is used to differentiate memory and I/O address.
(ii) When the processor is accessing memory locations M/IO is asserted high
and when it is accessing I/O mapped devices is asserted low.
4. What is the function of Instruction Pointer (IP) ?
The function of instruction pointer is to increment its value after executing
every instruction. It contains a 16-bit offset address of the instruction.
5. What are the functions of Bus Interface Unit (BIU)?
The functions of bus interface unit are:
(i) BIU sends address.
(ii) Fetches the instruction from memory.
(iii) Reads data from ports.
(iv) Writes data to ports.
6. What are the functions of control unit?
The functions of control unit are:
(i) Generate the sequence of control signals
(ii) All operations are controlled by control unit.
7. What is pipelined architecture? (AU-JUN’07)
Pipelined architecture is the processor in which the number of functional units and
the execution time of the functional units are overlapped. Each functional unit works
independently most of the time.
8. Write the special functions carried by the general purpose registers of 8086.
The special functions carried by the registers of 8086 are the following
(i) AX : 16 bit accumulator
(ii) AL : 8 bit accumulator
(iii) BX : Base Register
(iv) CX : Count Register
(v) DX : Data Register
9. What are the functional units available in 8086 architecture?
The functional units available in 8086 architecture are
Bus interface unit (BIU) and execution unit (EU).
10. What is pipelining? (AU-NOV’06)
Pipelining is fetching the next instruction while the current instruction gets
executed.
11. What is meant by memory segmentation?
Memory segmentation is the process of completely dividing the physically
available memory into a number of logical segments. Each segment is 64Kbyte in size
and is addressed by one of the segment register.
12. What are the advantages of segmented memory?
The advantages of segmented memory are:
(i) Allows the memory capacity to be 1 Mbyte, although the actual
addresses to be hardled are of 16-bit size.
(ii) Allows the placing of code , data and stack portions of the same
program in different parts of memory for data and code protection.
(iii) Permits a program and/or its data to be put into different areas of memory,
each time program is executed.
13. What are the two parts of a flag register?
The two parts of a 16-bit flag registers are:
(i) Condition code or status flag register: It consists of six flags to
indicate some condition produced by an instruction.
(ii) Machine control flag register: It consist of three flags and are used to
control certain operations of the processor.
14. Write the flags of 8086.
The 8086 has nine flags and they are:
Carry Flag (CF)
Parity Flag (PF)
Auxiliary Carry Flag (AF)
Zero Flag (ZF)
Sign Flag (SF)
Overflow Flag (OF)
Trace Flag (TF)
Interrupt Flag (IF)
Direction Flag (DF)
15. How clock signal is generated in 8086? What is the maximum internal clock
frequency of 8086? (AU-JUN’07)
The 8086 does not have on-chip clock generation circuit. Hence the clock
generator chip 8284 is connected to the CLK pin of 8086. The clock signal supplied
by 8284 is divided by three for internal use.
The maximum internal clock frequency of 8086 is 5MHz.
16. What is effective address? And calculate the effective address for the instruction
ADD AX,2536(BX)(SI). (AU-NOV’06)
The effective address is the combination of the BX or BP register contents, SI or
DI register contents and a displacement. The effective address may also be placed
directly in the instruction.
The effective address for the instruction ADD AX, 2536(BX)(SI) is,
EA= (DS)*10+2536+(BX)+SI)
17. What is the function of Queue in 8086?
The function of Queue in 8086 is to prefetche up to 6 instruction bytes and store
in a first in first out register, which increases the speed of program execution.
18. State the function of direction flag.
The function of direction flag function is used for string manipulation.
If the flag bit is 0, the string is processed beginning from the lowest address
to the highest address – auto incrementing mode.
Otherwise the string is processed from the highest address towards the
lowest address – auto decrementing mode.
19.What are the different addressing modes are used in 8086?
The different addressing modes in 8086 are:
(i) Immediate
(ii) Direct
(iii) Register
(iv) Register Indirect
(v) Indexed
(vi) Register Relative
(vii) Based Indexed
(viii) Relative Based Indexed
20.What is inter segment and intra segment mode?
Inter segment is a mode to which the control is to be transferred lies in a different
segment other than the current one the mode.
Intra segment is a mode to which the control lies in the same segment.
21.What are the different types of instruction set in 8086 microprocessor?
The different types of instruction set in 8086 microprocessor are:
(i) Data copy / transfer instructions
(ii) Arithmetic and logical instructions
(iii) Branch instructions
(iv) Loop instructions
(v) Machine control instructions
(vi) Flag manipulation instructions
(vii) Shift and rotate instructions
(viii) String instructions
22. What is the operation performed by the instruction CBW and CWD of 8086?
CBW(Convert Byte to Word): This instruction converts a signed byte to a signed
word. It copies the sign bit of a byte to be converted to all the bits in the higher
byte of the result word.
CWD(Convert Word to Double Word): This instruction copies the sign bit of AX
register to all bits of the DX register.
23. Define EQU and DB directive.
EQU: It is used to assign names to constants.
DB: It is used to assign names to variable.
24. What is nested macro?
Nested macro is defined as defining a macro in another macro (or) calling a
macro from inside a macro.
25. Differentiate between macro and subroutine.
The difference between macro and subroutine are:
Macro
Subroutine
1.It does not utilize the service of
stack.
2.Less time for execution.
3.Requires more memory space for
execution.
It utilizes stack service.
More time for execution.
Requires less memory space for
execution.
28. What is the purpose of CLK signal in an 8086 system? (AU-NOV’06)
The purpose of CLK signal in an 8086 system is to provide
internal timing. The range of clock rate is 5MHz for 8086.
29. What is the use of Latch signal on the AD0 – AD15 bus in an 8086 system?
(AU-NOV’06)
The use of Latch signal on the AD0 – AD15 bus in an 8086 system is
to demultiplex the address and data bus.
31. How the interrupts can be masked/unmasked in 8086? (AU-JUN’07)
32. What are the signals involved in memory bank selection in 8086
micro processor? (AU-JUN’07)
The signals involved in memory bank selection in 8086
micro processor are bank0 and bank1.
Bank0 is referred to as even addressed memory bank,
and bank1 is referred to as odd addressed memory bank.
34. What are the different types of interrupts in 8086? (AU-JUN’06)
The different types of interrupts in 8086 are:
1. Type 0: Divide by zero interrupt
2. Type 1: Single step interrupt
3. Type 2:Non maskable interrupt
4. Type 3: Breakpoint
5. Type 4: Overflow interrupt
6. Software interrupts
7. Type 0-255
35. State the interrupt priorities of 8086? (AU-JUN’06)
The interrupt priorities in 8086 is given by
Interrupt
Divide Error,Int n, Int 0
Priority
HIGHEST
NMI
INTR
SINGLE-STEP
LOWEST
37. What is an assembler directives? (AU-JUN’07)
The assembler directives is an collection of instructions, which contain
directions to the assembler. Also called as pseudo operations.
38. What is meant by software interrupt in 8086 ? (AU-JUN’07)
Software interrupt in 8086 are the interrupts used to vcall the
desired routines from many different programs in a system.
40. What is segment override prefix ?Give an example. (AU-JUN’07)
The segment override prefix is an additional 8-bit code
which is put in memory before the code for the rest of the instruction.
This additional code selects the alternate segment register.
41. Why we use MN/MX pin in 8086? (AU-NOV’07)
MN/MX pin in 8086 is used to operate in two modes.
MN/MX pin is high -minimum mode which is opted for the smaller systems
by means of single processor.
MN/MX pin is low - maximum mode is opted for the larger systems by
means of more than one processor.
42. Differentiate memory mapped and program controlled I/O. (AU-NOV’07)
43.What information is conveyed when QS1 QS0 bits are 01? (AU-APR’08)
44. What is the addressing mode of the following instructions? (AU-APR’08)
JMP [3001 H]
MOV AX, 55H [BX] [SI]
45. What happen in 8086 when DEN = 0 and DIR =1? (AU-APR’08)
46. What is the storage space required to store the interrupt
vectors of 8086? (AU-APR’08)
PART B
1. Explain the architecture of 8086 with neat diagram.
(AU- MAY’08) (AU- NOV’06) (16)
2. Explain the different types of instruction set in 8086 with example.
(AU- MAY’07) (AU-JUN’07)
(16)
3. Explain the different types of addressing mode with example.
(AU-JUN’06) (AU- NOV’06) (AU-JUN’07) (16)
4. Discuss the different assembler directives and their functions in detail.
(AU-May’08) (16)
5. What is interrupt? Explain their types in detail
6. Write a program to find the number of positive numbers and negative numbers
in a given series of signed numbers using 8086. (AU- MAY’08) (8)
7. Write an assembly language program in 8086 to find the sum of numbers in
the array. (AU- MAY’07) (10)
8. Write short notes on MACROS. (AU- MAY’07) (AU-JUN’07) (6)
9. With the neat sketch explain the architecture of an 8086 processor.
(AU-NOV’06)
(12)
10. Give the significance of O Flag, T Flag and I Flag, D Flag of 8086.
(AU-NOV’06)
(4)
11. Explain in detail about the various addressing modes used in 8086 processor?
Give an example. (AU-NOV’06)
(12)
12. Name the various segment registers and their usage in 8086 processor.
(AU-NOV’06)
(4)
13. Explain the MN/MX mode operation of an 8086 processor.
(AU-NOV’06)
(10)
14. Explain in detail about the 8086 memory banks and the associated
signals for byte and word operations. (AU-NOV’06)
(12)
15. Give the significance of RQ/GT0 and IO/M signals. (AU-NOV’06)
(4)
16. Describe the action taken by 8086 when INTR pin is activated.
(AU-JUN’07)
(6)
17.Write an assembly language program in 8086 to search the largest data in
an array. (AU-JUN’07)
(10)
18. Discuss the various addressing modes of 80896 microprocessor.
(AU-JUN’07)
(10)
19. Explain the following assembler directives used in 8086. (AU-JUN’07) (6)
(1) ASSUME
(2) EQU
(3) DW
20. Explain in detail about memory access mechanism in 8086.
(AU-JUN’07)
(8)
21. Explain the function of following 8086 signals. (AU-JUN’07) (8)
(1) HLDA
(2) RQ/GT0
(3) DEN
(4) ALE.
22.Draw and explain a block diagram showing 8086 in maximum mode
configuration. (AU-JUN’07)
(12)
23. Describe the procedures and macros of 8086. (AU-JUN’06) (16)
24. With a neat sketch describe the minimum and maximum mode of
operation of 8086. (AU-JUN’06) (16)
25. Describe the system design using 8086. (AU-JUN’06) (16)
26 Write an assembly language program in 8086 to find the sum of numbers
in the array. (AU-JUN’07) (8)
27. Explain the maximum mode operation of 8086. (12) (AU-JUN’07
28. Write notes on addressing memory (4) (AU-JUN’07
29. Explain the Minimum mode operation of 8086. (AU-JUN’07) (12)
30. Write notes on addressing Input/Output devices. (AU-JUN’07) (4)
31. Discuss in detail about the interrupts and interrupt service routines with
interrupt cycle of 8086. (AU-NOV’07)
(16)
32. Write an assembly language program to find out the largest number
from a given unordered array of 8 bit numbers, stored in the locations
starting from a known address. (AU-NOV’07)
(16)
33. Explain the I/O addressing capability of 8086. (AU-NOV’07)
(4)
34. Write a program to find the number of positive numbers and negative
numbers in a given series of signed numbers using 8086. (AU-APR’08) (8)
35. Explain the following assembly directives. (AU-APR’08)
(8)
SHORT, TYPE, FAR PTR
36. Explain the maximum mode of 8086 with the timing diagrams of memory
read cycles, memory write cycles and RQ | GT timing. (AU-APR’08) (16)
UNIT III
MULTIPROCESSOR CONFIGURATION
PARTA
1. What is a co-processor? How is it useful? (AU-NOV’09)
The co processor is the processor which executes the instructions fetched for it
by host processor. It is designed to work in parallel with a microprocessor.
2. What is independent processor?
An independent processor is demy ask for a bus access, may itself fetch the
instructions and execute them independently.
3. Define multiprocessor.
A multiprocessor system is defined as the processor which have two or more
processors that can execute instructions (or perform operations ) simultaneously.
4. List out the advantages of multiprocessor system.
The advantages of multiprocessor system are:
(i) Several low cost processors may be combined to fit the needs of an application.
(ii) Implementation of modular processing of task can be achieved.
(iii) When a failure occurs, it is easier to replace only the failure part/processor.
5. What are the major issues of multiprocessor system design?
The two major design multiprocessor system design are
bus contention and inter processor communication.
6. Explain why the processor utilization rate can be improved in a multiprocessor
system by an instruction queue. (AU-APR’08)
PART B
1. Explain the minimum mode of operation of Coprocessor in detail.
2. Explain the signal pin description of coprocessor with pin diagram.
3. Design of a PC based multiprocessor system.
4. Discuss in detail about the interconnecting topologies of a multiprocessor
system. (AU-NOV’07) (16)
5. Discuss the software aspects of a multiprocessor system. (AU-NOV’07) (12)
6. Discuss about the multiprocessor configurations of 8086. (AU-APR’08) (16)
7. Explain why the processor utilization rate can be improved in a multiprocessor
system by an instruction queue. (AU-APR’08)
8. What are the advantages of the multiprocessor systems? (AU-MAY’07) (4)
9.What is a coprocessor? Explain the architecture of any math processor.
(AU-MAY’06) (8)
10. What is multiprocessor system? Explain the interconnection topologies
and its software aspects. (AU-MAY’06)
(8)
11. Explain Loosely coupled system with block diagram and list its advantages.
(AU-NOV’06) (6)
12. What are the advantages of the multiprocessor systems over the single
CPU system? Write briefly on the private I/O bus configuration.
(AU-MAY’07)
(16)
13. Write short notes Coprocessor. (AU-MAY’07) (8)
14. Describe closely coupled and loosely coupled configuration.
(AU-NOV’07)
(16)
UNIT IV
I/O INTERFACING
PART A
1. What are the advantages of DRAM?
The advantages of DRAM are,
1. Higher packaging density
2. Lower cost
3. Less power consumption
2. How the refresh cycle is different from memory read cycle?
The refresh cycle is different from the memory read cycle in the following aspects.
(i) The memory address is not provided by the processor address bus, rather
it is generated by a refresh mechanism counter known as refresh counter.
(ii) Unlike memory read cycle, more than one memory chip may be enabled at a
time so as to reduce the number of memory refresh cycles.
(iii) The data enable control of the selected memory chip is deactivated, and
data is not allowed to appear on the system data bus during refresh.
(iv)
Memory refresh is an independent regular activity.
3. What are the methods of interfacing I/O devices? (AU-Nov’06)
The two methods of interfacing general i/o devices are:
1. I/O mapped
2. Memory mapped
4. What are the modes of operation is used in 8255?
The modes of operation used in 8255 are:
1. I/O mode
(i) Mode 0 (Basic I/O)
(ii) Mode1 (Strobed I/O)
(iii) Mode 2 (Strobed bidirectional I/O)
2. BSR mode (Bit Set/ Reset Mode)
5. What are the features of mode 0 in 8255?
The features of mode 0 in 8255 are:
1. Two 8-bit ports(port a & port B) and two 4-bit ports
(port C upper and lower) are available.
2. Any port can be used as an input or output port.
3. Output ports are latched. Input ports are not latched.
4. A maximum of four ports are available so that overall 16 I/O
configurations are possible.
6. What are the features of Mode 1 in 8255?
The features of mode 1 in 8255 are:
1. Two groups- group A and group B are available for strobed data transfer.
2. Each group contains one 8-bit data I/O port and one 4-bit control/data port.
3. The 8-bit data port can be either used as input or an output port.
4. Both the inputs and outputs are latched.
7. What are the inputs and output control signals used in mode 1 of 8255?
Input control signals are: STB, IBF, INTR
Output control signals are: OBF, ACK, INTR
8. What are the features of mode 2 of 8255?
The features of mode 2 of 8255 are:
1. The single 8-bit port in group A is available.
2. The 8-bit port is bidirectional and additionally a 5-bit control bit is available.
3. Three I/O lines are available at port C.
4. Inputs and outputs both are latched.
5. The 5-bit control bit in port C is used for generating/accepting
handshake signals for the 8-bit data transfer on port A.
9. What are the different mode of operation of Timer(8253)?
(AU-May’06) (AU-NOV’06)
The different mode of operation of timer (8253) are:
1. Mode 0 (Interrupt or terminal count)
2. Mode 1 (Programmable monoshot)
3. Mode 2 (Rate generator)
4. Mode 3 (Square wave generator)
5. Mode 4 (Software triggered strobe)
6. Mode 5 (Hardware triggered strobe)
10. What is rate generator?
Rate generator in timer mode 2 is divide by N counter. In this mode, if N is
loaded as the count value, then after N pulses the output becomes low only for one
clock cycle. The count N is reloaded and again the output becomes high and remains
so for N clock pulses.
11. What is the function of priority resolver?
The function of priority resolver unit determines the priorities of the
interrupt requests appearing simultaneously. The highest priority is selected
and stored into the corresponding ISR bit during INTA pulse.
12. What is PS/EN pin? (AU-May’07)
PS/EN pin is a dual purpose pin. When the chip is used in buffered mode, it
can be used as a buffer enable to control buffer transreceivers. If this is not used in
buffered mode then the pin is used as input to designate whether the chip is used as a
master or a slave.
13. What are the modes of 8259? (AU-May’05)
The modes of 8259 are:
1. Fully nested mode
2. End of Interrupt (EOI)
3. Automatic Rotation
4. Automatic EOI mode
5. Specific Rotation
6. Special mask mode
7. Edge/level triggered mode
8. Reading 8259 status
9. Poll command
10.Special fully nested mode
11.Buffered mode
12.Cascade mode
14. What is the function of scan counter? (AU-Nov’06)
The function of scan counter is to scan the key matrix and refresh the display
with two modes.
Encoded mode: The counter provide a binary count that is to be externally decoded
to provide the scan lines for keyboard and display.
Decoded mode: The counter internally decodes the least significant 2-bits and provides
a decoded one out of 4 scan on SL0-SL3.
15. What are operations of 8279?
The operations of 8279 are:
1. Keyboard mode
(i) Scanned keyboard mode with 2 key lock out
(ii) Scanned keyboard mode with N key rollover
(iii) Scanned keyboard special error mode
(iv) Sensor matrix mode
(v) Strobed input mode
2. Display mode
(i) Left entry mode
(ii) Right entry mode
16. List out three modes of Data Transmission. (AU-NOV’08)
The three modes of data communication are:
1. Simplex
2. Duplex
3. Half duplex
17. What is USART? ( AU-May’07)
USART is a Universal Synchronous Asynchronous Receiver and Transmitter.
It is mainly used for serial communication. It converts parallel data into a
serial stream of bits suitable for serial transmission. It also receive a serial stream
of bits and convert it into parallel data bytes to be read by a microprocessor.
18. What are the advantages of DMA? (AU-Nov’06)
The advantages of Direct Memory Access are:
(i) DMA mode of data transfer is the fastest amongst all the modes of data transfer.
(ii) In this mode, the device may transfer the data directly to/from memory without
any interference from the processor.
19. What is the function of mode set register?
The function of the mode set register is to enable the DMA channels individually
and also set the various modes of operation.
20. What are the types of operation in DMA? ( AU-May’05)
The three types of DMA operation are,
1. Verify DMA operation
2. Write operation
3. Read operation
21. List the types of priorities used in DMA. (AU-May’06)
The types of priorities used in DMA are,
1. Fixed priority scheme
2. Rotating priority scheme.
22. Which type of decoding requires minimum hardware? (AU-APR’08)
23. What is key bouncing? (AU-APR’08)
24. Name the two modes used by the DMA processes to transfer data. (AU-NOV’06)
The two modes used by the DMA processes to transfer data are
1. Single transfer mode.
2. Block transfer mode.
3. Demand transfer mode.
26. What is the function of gate signal in 8254 timer? (AU-JUN’07)
The function of gate signal in 8254 timer is:
Gate = 1 enables counting
Gate = 0 disables counting
27. Write the format of ICW1 in 8259. (AU-JUN’07)
The format of ICW1(Initialization command word1) in 8259 is :
A0
D7
D6
D5
D4
D3
D2
D1
D0
0
A7
A6
A5
1
LTIM ADI SNGL
IC4
28. 8253's OUT signal is to be used as a clock input of the desired frequency to a
particular device. Is it possible? How? (AU-NOV’09)
29. How is a memory-to-memory transfer accomplished using 8237? (AU-NOV’09)
31. What is the use of IRR (Interrupt Request Register)? (AU-NOV’08)
32. List the uses of USART. (AU-NOV’07)
The uses of USART are:
(i) At the transmission, it converts byte into eight serial bits.
(ii) At the reception, the serial bits are converted into parallel 8 bit data.
33. Describe the three major tasks needed to get meaningful information from
matrix keyboard. (AU-APR’08)
34. What are the different ways in which the 8-bit data bus of an interfacing
device can be connected to the 16 bit data bus of 8086? (AU-APR’08)
35. State the function of DSR and DTR pins in 8251. (AU-JUN’06)
36. List the features of 8259. (AU-JUN’06)
The features of 8259 are:
1. It is designed to minimize the software and real time overhead in
handling multi-level priority interrupts.
2. The 8259 can be programmed to accept either the level triggered or
the edge triggered interrupt request.
3. With the help of 8259 user can get the information of pending interrupts,
in-service interrupts and masked interrupts.
37. List the features of 8251. (AU-JUN’07)
The features of 8251 are:
1. It is an universal synchronous and asynchronous communication
controller.
2. It has built in baud rate generator.
3. It allows full duplex transmission and reception.
4. It is compatible with an extended range of Intel microprocessors.
38. What is the internal operating frequency of the 8279?How can you derive it
from any available clock signal? (AU-JUN’07)
39. Differentiate memory mapped and program controlled I/O. (AU-NOV’07)
40. What are the advantages of DRAM? (AU-NOV’07)
PART B
1. Explain in detail about DMA controller. (AU-Nov’06)
2. What is USART? Explain in detail. (AU-May’07)
3. Explain the keyboard and display controller with neat block diagram.
(AU-Nov’07, May’08)
4. Explain the programmable interrupt controller 8259 in detail. (AU-May’06) (16)
5. Explain the programmable interval timer 8253. (AU-May’06) (16)
6. Explain the parallel communication chip 8255 in detail. (AU-May’06) (16)
7. With a neat diagram, explain how 8251 is interfaced with 8085 and
used for serial communication. (AU- MAY’07) (16)
8. Describe the architecture and working of 8253. (AU- MAY’08) (12)
9. Describe the working of 8259 interrupt controller. (AU- MAY’08)
(AU- NOV’06) (10)
10. What is the use of CAS0, CAS1 and CAS2 signals? (AU- NOV’06) (4)
11. Write a program to generate triangular waveform using DAC 0800.
(AU-APR’08) (4)
12. Write an ALP to receive 100 bytes of data string serially using 8251.
(AU-APR’08) (6)
13. Draw the block diagram of Keyboard/display controller 8279 and
describe its operations. (AU-JUN’07) (AU-NOV’07) (16)
14. What is the use of DMA controller? Explain its operations with neat
block diagram. (AU-NOV’07) (16)
15. With a neat sketch and explain the operation of an Interrupt controller (8259)
(AU-NOV’06)
(14)
17. Draw the block diagram of a DMA controller (8237) and explain its operation.
(AU-NOV’06)
(16)
18. With the help of block diagram explain the operation of USART (8251A)
(AU-JUN’07)
(10)
19. Discuss the salient features of 8259 – programmable interrupt controller.
(AU-JUN’07)
(6)
20. Describe the various modes of operations in 8253 programmable interval Timer.
(AU-JUN’07) (8)
21. Explain the operation of DMA controller (8237). (AU-JUN’06) (16)
(AU-JUN’07) (8)
22. With a neat diagram discuss the various modes of operation of 8255.
(AU-JUN’07)
23. Show how two 8255 chip can be connected in an connected in an 8086-based
system to form a 16-bit port. (AU-NOV’09)
24. With a neat diagram discuss the operation of a DMA controller. Show how
such a controller can be connected in an 8086-based system. (AU-NOV’09)
24. Draw the block diagram of 8257 and explain the functions of each block.
(AU-NOV’08)
26. With a neat block diagram, explain in detail the internal architecture of 8257
and its register organization. (AU-NOV’07)
(16)
27. Discuss about the architecture, Signal description and modes of operation
of 8279. (AU-NOV’07) (16)
28. Discuss how the DMA controller is interfaced with the 8085 processor.
(AU-APR’08)
(16)
29. Discuss in detail about the programmable interrupt controller and its
cascading mode of operation. (AU-APR’08)
(16)
31. With block diagram explain Interrupt controller. (AU-JUN’06) (16)
33. With a neat diagram ,explain how 8251 is interfaced with 8085 and used
for serial communication. (AU-JUN’07) (16)
UNIT V
MICROCONTROLLER
PART A
1. What is meant by microcontroller?
A microcontroller is a device which contains the microprocessor with integrated
peripherals like memory, serial ports, parallel ports, timer/counter, interrupt controller .
2. List the advantages of microcontroller. (AU-NOV’07)
The advantages of microcontroller are:
1. As the peripherals are integrated into a single chip ,
the overall system cost is very low.
2. Size of the product is very small compared to the microprocessor based system.
3. System design requires very little efforts and is easy to maintain.
4. As the peripherals are integrated with a microprocessor ,
the system is more reliable.
5. All these features are available in a 40 pin package as in an 8-bit processor.
6. Though a microcontroller may have internal memory & I/O ports may
be interfaced externally, if required.
3. What is PSW?
Program Status Word (PSW) is the set of flags contains the status information and
is considered as one of the special function registers.
4. What is stack pointer (SP)?
Stack Pointer (SP) is a 8- bit wide register and is incremented before the data is
stored into the stack using push or call instructions. It contains 8-bit stack top address.
The stack may be defined anywhere in the on-chip 128 byte RAM.
5. What is the function of DPTR register? (AU-JUN’07) (AU- NOV’08)
The function of data pointer is a 16-bit register which contains a higher byte
(DPH) and the lower byte (DPL) of a 16-bit external data RAM address. It has been
allotted two addresses in the special function register bank for its two bytes DPH
and DPL.
6. What is a serial data buffer?
Serial data buffer is a special function register and it initiates serial transmission
when byte is written to it and if read, it reads received serial data. It internally contains
two independent register. One is a transmit buffer which is necessarily a parallel-in
serial-out register. The other is called receive buffer which is serial-in parallel-out
register.
7. What is the use of timing and control unit?
Timing and control unit is used to drive all the necessary timing and control
signals required for the internal operation of the circuit. It also derives control signals
that are required for controlling the external system bus.
8. What is the purpose of using instruction register?
Instruction register is used for the purpose of decoding the opcode of an
instruction to be executed and gives information to the timing and control unit
generating necessary signals for the execution of the instruction.
9. Give the purpose of ALE/PROG signal.
The purpose of address latch enable (ALE/PROG) output pulse indicates that the
valid address bits are available on their respective pins.
10. What is PSEN signal?
Program store enable is an active-low output signal that acts as a strobe to read
the external program memory. This goes low during external program memory
accesses.
11. What are the functions of port 0 pins in 8051?
The functions of port o pins in 8051 are:
(i) Port 0 pin act as an 8-bit bidirectional bit addressable I/O port.
(ii) Port 0 acts as multiplexed address/data lines during external memory access, i.e.
when EA is low and ALE emits a valid signal.
(iii) In case of controllers with on-chip EPROM, port 0 receives code bytes during
programming of the internal EPROM.
12. What is TCON?
TCON is a timer/counter control register. Some of the bits of this register are
used to turn the timers on or off. This register also contains interrupt control flags for
external interrupts INT0 and INT1.
13. What are the power saving modes of operation?
The two power saving modes of operation are,
1. Idle mode
Power down mode
14. What is idle mode and how this mode is terminated?
In the idle mode, the oscillator continues to run and the interrupt, serial port and
timer blocks are active but the clock to the processor is disabled. The processor status
is preserved. This mode can be terminated with a hardware interrupt or hardware reset
signal. After, this processor resumes program execution from where it left off.
15. What is power down mode and how this mode is terminated?
In power down mode, the on-chip oscillator is stopped. All the functions of the
controller are held maintaining the contents of RAM. The only way to terminate this
mode is hardware reset. The reset redefines all the SFRs but the RAM contents are left
unchanged.
16. What is the clock frequency of timer?
The clock frequency of timer is 1/32 th of the controller operating frequency.
The controller operating frequency is 12MHz to 16MHz.
17.Give the priority level of the interrupt sources.
The priority level of the interrupt sources are,
Interrupt Source
IE0 (External INT0)
TF0 (Timer 0)
IE1 (External INT1)
TF1 (Timer1)
RI=TI (Serial Port)
Priority within a level
Highest
“
“
“
Lowest
18. List the addressing modes of 80851 microcontroller? (AU-NOV’07)
The six addressing modes available in 8051 are,
1. Direct addressing
2. Indirect addressing
3. Register addressing
4. Register Specific (Register Implicit)
5. Immediate addressing
6. Indexed addressing
19. What is immediate addressing?
In this addressing mode, an immediate data, i.e. a constant is specified in
the instruction after the opcode byte.
Example:
ADD A, #100
20. What is indirect addressing mode?
In this mode of addressing, the 8-bit address of an operand is stored in a register
and the register, instead of 8-bit address, is specified in the instruction. The register R0
and R1 of the selected bank of registers or stack pointer can be used as address registers
for storing 8-bit addresses. The address register of 16-bit addresses can only be data
pointer.
Example:
ADD A,@R0
21. Write program to load accumulator, DPH and DPL using 8051.
MOV A,#30
MOV DPH,A
MOV DPL,A
22. Write a program to subtract two 8-bit numbers and exchange the digits
using 8051.
MOV A,#9F
MOV R0,#40
SUBB A,R0
SWAP A
23. What is watch dog timer (WDT)?
The Watch Dog Timer is a dedicated timer to take care of system malfunction.
It can be used to reset the controller during software malfunction, which is referred to
as “hanging”. A microcontroller will have facility for enabling or disabling the WDT.
24. Mention few differences between microprocessor and microcontroller.
(AU-APR’08)(AU-NOV’06)
The differences between microprocessor and microcontroller are,
S.NO
1.
2.
MICROPROCESSOR
It is concerned with rapid
movement of code and data
between external memory and
processor.
The microprocessor will have few
MICROCONTROLLER
It is concerned with rapid
movement of code and data
within the controller.
The microcontroller will have
bit manipulating instructions.
large number of bit manipulating
instructions.
3.
The microprocessors are
generally used for designing
general purpose systems.
The microcontrollers are used for
designing dedicated applications
in specific systems.
4.
It has single memory map for data It has separate
and code.
Less number of pins are
More number of pins are
multifunctioned.
multifunctioned.
5.
25. Draw the format of PSW in 8051. (AU-NOV’07)
D7
CY
D6
AC
D5
F0
D4
RS1
D3
RS0
D2
OV
D1
-
D0
P
CY – Carry Flag
AC – Auxiliary Carry Flag
F0 - Flag 0 is available to the user for general purpose.
RS1 – Register bank selector bit 1.
RS0 – Register bank selector bit 0.
OV – Overflow Flag
P - Parity flag
26. How does the status of EA pin affect the access to internal and external
program memory? (AU-APR’08)
27. State the difference between RET and RET1 instruction in 8051. (AU-APR’08)
28. Differentiate RRA and RCA instruction in 8051 microcontroller. (AU-NOV’06)
29. List the interrupts of 8051 micro controller. (AU-JUN’07)
The interrupts of 8051 micro controller are:
1. External interrupt 0 : IE0 : 0003H
2. Timer interrupt 0 : TF0 : 000BH
3. External interrupt 1 : IE1 : 0013H
4. Timer Interrupt 1 : TF1 : 001BH
Serial Interrupt
5. Receive interrupt : RI : 0023H
6. Transmit interrupt: TI : 0023H
30. What are register banks in 8051 microcontroller? (AU-JUN’07)
The register banks in 8051 microcontroller are RS0 and RS1
RS1 RS0
Bank selection
0
0
Bank 0
0
1
Bank 1
1
0
Bank 2
1
1
Bank 3
31. What are the addressing modes supported by 8051? (AU- NOV’09)
The addressing modes supported by 8051 are:
1. Register addressing
2. Direct byte addressing
3. Register indirect addressing
4. Immediate addressing
5. Register specific
6. Index
32. Write an 8051program to divide two 8-bit number. (AU- NOV’09)
Program to divide two 8-bit number:
MOV A, # 90
MOV B, # 20
DIV AB
33. What do you mean by Indirect Addressing Mode? (AU- NOV’08)
In indirect addressing mode R0 and R1 of each register bank
can be used as an index or pointer register.
34. What is the function of DPTR register? (AU-JUN’07) (AU- NOV’08)
35. How many interrupt sources are available in 8051? What are they?
(AU-NOV’07)
36. Write short description on register bank registers and their uses.
(AU-NOV’07)
1. There are four register banks numbered 0 to 3 and each consists
of eight registers named R0 to R7.
2. Each register can be addressed by name or by its RAM address.
3. Only one register bank is in use at a time.
4. Register banks when not selected can be used as general purpose RAM.
37. How does 8051 differentiate between the external and internal
program memory? (AU-APR’08)
38. List the features of 8051? (AU-JUN’06)
The features of 8051 microcontroller are:
1. The 8051 microcontroller is an 8-bit microcontroller initially
developed by INTEL in the year 1980.
2. Single supply +5 volt operation using HMOS technology.
3. 4096 bytes program memory on chip(not on 8031)
4. 128 data memory on chip.
5. Four register banks.
6. Two multiple mode,16-bit timer/counter.
7. Extensive boolean processing capabilities.
8. 64 KB external RAM size
9. 32 bidirectional individually addressable I/O lines.
10. 8 bit CPU optimized for control applications.
39. State the function of DSR and DTR pins in 8251. (AU-JUN’06)
40. What is jump range in 8051? (AU-JUN’07)
42. Draw the format of timer mode control register. (AU-NOV’07)
PART B
1. Draw and discuss the internal architecture of 8051. (AU-NOV’06)
(AU-JUN’07) (AU-APR’08) (AU-NOV’08)
2. Explain the signal pin description of 8051. (AU-NOV’06) (AU-MAY’08)
3. Draw and discuss the formats and bit definitions of the SFR registers.
(AU-JUN’07) (8)
4. Explain the different type of addressing mode of 8051 with example.
(AU-NOV’07) (8)
5. Write short notes on Memory and I/O addressing. (AU-JUN’07)
6. Write short notes on interrupt of 8051. (AU- NOV’08) (8)
7. Write a program to find the number of positive and negative numbers
in a given array. (AU-APR’08)
(6)
8. Discuss any two applications of microcontroller. (AU-APR’08) (16)
9. Discuss in detail about the register set of 8051. (AU-NOV’07) (10)
10. Describe the use of the following signals: (AU-NOV’07)
(6)
(1) PSEN
(2) EA
(3) PORT1
11. Design a micro controller 8051 based length measurement system.
(AU-NOV’07) (16)
12. Discuss in detail about 8051 based stepper motor control. (AU-JUN’07)
13. Show how the 8051 can be used to control the operation of an elevator system.
Assume the elevator is to operate between three floors. Show the hardware interface
and the required 8051 program. (AU- NOV’09) (16)
15. Explain the instruction set of 8051. (AU- NOV’08) (8)
16. How many addressing modes are available in 8051? Explain them with
examples. (AU-NOV’07) (8)
17. Tabulate the program control instructions of 8051 and explain any five of them.
(AU-NOV’07) (8)
18. With a neat sketch, explain the internal working of 8051 with its signal
descriptions. (AU-NOV’07) (16)
19. Write short notes about the following in relevance to 8051. (AU-NOV’07) (16)
(i) Memory addressing
(ii) External I/O addressing
(iii) Interrupts.
20. Discuss the register set of 8051 and also discuss how memory and I/O
addressing is done in 8051. (AU-APR’08) (16)
21. How do you interface a stepper motor to a controller? Give the necessary
hardware and software functional blocks. (AU-NOV’07) (8)
22. Code a program to rotate stepper motor continuously using 8051.
(AU-NOV’07) (8)
23. Explain the operational features of 8051. (AU-JUN’06) (16)
24. Describe the memory and I/O addressing of 8051. (AU-JUN’06) (16)
25. Explain the interrupt structure of 8051. (AU-JUN’07) (8)
26. Write short notes on SFR and Timers. (AU-JUN’07) (8)