250+ TOP MCQs on Do’s and Don’ts While Using Instructions and Answers

Microprocessors Technical Interview Questions & Answers on “Do’s and Don’ts While Using Instructions”.

1. The logic required for implementing a program can be expressed in terms of
a) flowchart
b) algorithm
c) flowchart & algorithm
d) none of the mentioned
Answer: c
Clarification: The logic required for implementing a program must be visualized clearly which is possible by flowchart and algorithm.

2. The operands, source and destination in an instruction cannot be
a) register, register
b) memory location, memory location
c) memory location, register
d) immediate data, register
Answer: b
Clarification: Only one memory operand can be specified in one instruction.

3. The instruction that is not possible among the following is
a) MOV AX, BX
b) MOV AX, [BX].
c) MOV 55H, BL
d) MOV AL, 55H
Answer: c
Clarification: 8-bit or 16-bit operand cannot be used as a destination operand.

4. The instruction that is not possible among the following is
a) MOV AX, [BX].
b) MOV AX, 5555H
c) MOV AX, [SI].
d) MOV [SI], [DI].
Answer: d
Clarification: Both the operands cannot be memory operands.

5. Both the operands source and destination of an instruction cannot be
a) register, register
b) immediate data, register
c) register, immediate data
d) immediate data, memory location
Answer: c
Clarification: Since destination operand should not be immediate data.

6. The registers that cannot be used as operands for arithmetic and logical instructions are
a) general purpose registers
b) pointers
c) index registers
d) segment registers
Answer: d
Clarification: Segment registers are not allowed as operands for arithmetic and logical instructions.

7. The operands of an instruction cannot be
a) registers
b) memory operands and immediate operands
c) immediate operands
d) memory operands
Answer: b
Clarification: Both the operands should not be immediate operands and memory operands.