Pregunta 1
Pregunta
In 8085 microprocessor, the value of the most significant bit of the result following the execution of any arithmetic or Boolean instruction is stored in the
Respuesta
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carry flag
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auxiliary carry flag
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sign flag
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zero flag
Pregunta 2
Pregunta
How many bytes in a double word ?
Respuesta
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1 byte
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2 bytes
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3 bytes
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4 bytes
Pregunta 3
Pregunta
What is the value of AX register after executing,
MOV AX,456h,
CMP AX,456h
Pregunta 4
Pregunta
The instruction AND AH,11110111 is equivalent to
Respuesta
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Sub AH, 8, if 4th bit of AH is set
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Sub AH, 8, if 4th bit of AH is cleared
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Sub AH, 4, if 4th bit of AH is set
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None of the above
Pregunta 5
Pregunta
The debug command U
Respuesta
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Retrieve the assembly program instructions from the disk
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Retrieve the assembly program instructions from the RAM
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Convert the machine code stored in memory into assembly equivalent
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None of the above
Pregunta 6
Pregunta
The debug command: -E F000:0 1 2 3
Respuesta
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Has no effect, because that location in ROM
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Will write three bytes (1,2,3) starting at location F000:0
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Depends on the processor
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Invalid command
Pregunta 7
Pregunta
Consider the program segment:
Age DB 100
MOV Age,123
What is the memory-addressing mode of the first operand in the MOV instruction?
Pregunta 8
Pregunta
The multiple Segment:Offset representations for a unique physical address is:
Respuesta
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Advantage for 8086 processor to provide flexibility
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Disadvantage for 8086 processor, it make it harder to program
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Has no effect.
Pregunta 9
Pregunta
Algorithms are designed using combinations of three main building blocks (control structures), called...
Respuesta
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loops, if/then/else statements and functions
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quark, strangeness and charm
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syntax, choice and loops
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sequence, selection and repetition
Pregunta 10
Respuesta
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is written with specialised editing software
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cannot describe if...then...else constructs
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provides a pictorial representation of an algorithm
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has features of both English and computer languages
Pregunta 11
Pregunta
In an 8085 microprocessor, the instruction CMP B has been executed while the content of the accumulator is less than that of register B. As a result
Respuesta
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Carry flag will be set but zero flag will be reset.
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Carry flag will be reset but zero flag will be set.
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Both Carry flag and zero flag will be reset.
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Both Carry flag and zero flag will be set.
Pregunta 12
Pregunta
Consider the sequence of 8085 instructions given below:
LXI H, 9258
MOV A, M
CMA
MOV M, A
which one of the following is performed by this sequence?
Respuesta
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Contents of location 9258 are moved to the accumulator.
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Contents of location 9258 are compared with the contents of accumulator
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Contents of location 9258 are complemented and stored in location 9258
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Contents of location 5892 are complemented and stored in location 5892
Pregunta 13
Pregunta
The 2' s complement representation of the decimal value (minus) - 15 is
Pregunta 14
Pregunta
The instruction, MOV AX, 1234H is an example of
Pregunta 15
Pregunta
Match the following:
1. A Push Instruction a. Pre Increment the SP
2. A Pop Instruction. b. Post Increment the SP
c. Pre Decrement the SP
d. Post Decrement the SP.
Respuesta
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1-> a, 2 -> b
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1->b, 2 -> c
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1-> c, 2 -> d
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1-> d, 2->a
Pregunta 16
Pregunta
In 8085, which of the following modifies the program counter ?
Pregunta 17
Pregunta
The instruction that is used as prefix to an instruction to execute it repeatedly until the CX register becomes zero is
Pregunta 18
Pregunta
In 8086 microprocessor one of the following statements is NOT true.
Respuesta
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Coprocessor is interfaced in MAX mode
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Coprocessor is interfaced in MIN mode
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I/O can be interfaced in MAX / MIN mode
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Supports pipelining
Pregunta 19
Pregunta
The status flag that cannot be operated by direct instruction is
Pregunta 20
Pregunta
Interfacing devices for DMA controller, programmable interval timer are respectively
Respuesta
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8257, 8253
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8253, 8257
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8257,8251
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8251,8257
Pregunta 21
Pregunta
Which of the following are the three basic sections of a microprocessor unit?
Respuesta
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operand, register, and arithmetic/logic unit (ALU)
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control and timing, register, and arithmetic/logic unit (ALU)
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control and timing, register, and memory
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arithmetic/logic unit (ALU), memory, and input/output
Pregunta 22
Pregunta
The instruction, MOV AX, [BX] is an example of
Pregunta 23
Pregunta
Which of the following instruction is NOT valid?
Respuesta
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MOV AX, BX
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MOV DS, 5000H
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MOV AX, 5000H
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PUSH AX
Pregunta 24
Pregunta
The instruction that is used for finding out the codes in case of code conversion problems is
Pregunta 25
Pregunta
The instruction that performs logical AND operation and the result of the operation is not available is
Pregunta 26
Pregunta
The instruction that is NOT valid is
Respuesta
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MOV AX, [BX]
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MOV AX, 5555H
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MOV AX, [SI]
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MOV [SI], [DI]
Pregunta 27
Pregunta
In 8086 microprocessor, the stack segment may have a memory block of a maximum of
Respuesta
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32K bytes
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64K bytes
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16K bytes
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8K bytes
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Unlimited bytes.
Pregunta 28
Pregunta
In 8086 the overflow flag is set when______.
Respuesta
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The sum is more than 16 bit
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Carry and sign flags are set
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Signed numbers go out of their range after an arithmetic operation
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During subtraction
Pregunta 29
Pregunta
Direction flag is used with ____.
Respuesta
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String instructions
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Arithmetic Instructions
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Stack Instructions
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Branch Instructions
Pregunta 30
Pregunta
If_________ flag is set; the processor enters the single step execution mode.
Respuesta
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Direction
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Trap
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Interrupt
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Zero
Pregunta 31
Pregunta
If segment address = 1005 H, offset address = 5555 H, then the physical address is_____.
Respuesta
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6555A H
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155A5 H
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45500 H
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56555 H
Pregunta 32
Pregunta
BHE of 8086 microprocessor signal is used to interface the_____
Respuesta
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I/O
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DMA
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Even bank memory
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Odd bank memory