Instruction Set Architecture (ISA) MCQs

By: Prof. Dr. Fazal Rehman Shamil | Last updated: September 20, 2024

1. What does ISA stand for in computer architecture?

a) Instruction Set Architecture
b) Integrated System Architecture
c) Instruction System Array
d) Internal Structure Architecture

Answer: a) Instruction Set Architecture

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2. Which of the following is NOT a component of the ISA?

a) Addressing modes
b) Instruction formats
c) Registers
d) File system

Answer: d) File system

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3. Which of the following types of ISAs is commonly used in RISC architectures?

a) Stack-based
b) Accumulator-based
c) Register-based
d) Memory-based

Answer: c) Register-based

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4. In a stack-based ISA, where are operands typically stored?

a) Registers
b) Memory
c) A stack
d) Cache

Answer: c) A stack

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5. The MIPS architecture is an example of which type of ISA?

a) CISC
b) RISC
c) VLIW
d) SIMD

Answer: b) RISC

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6. Which architecture uses complex instructions and allows multiple operations in a single instruction?

a) CISC
b) RISC
c) EPIC
d) VLIW

Answer: a) CISC

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7. Which of the following is a characteristic of a RISC architecture?

a) Few registers
b) Complex addressing modes
c) Single-cycle execution
d) Multiple clock cycles per instruction

Answer: c) Single-cycle execution

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8. What is the main advantage of a RISC architecture?

a) Larger instruction set
b) Simpler hardware design
c) Complex instruction execution
d) Longer instruction decode times

Answer: b) Simpler hardware design

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9. Which of the following is NOT a typical feature of a CISC architecture?

a) Complex instruction formats
b) Multiple addressing modes
c) Pipeline-friendly design
d) Variable instruction lengths

Answer: c) Pipeline-friendly design

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10. In an accumulator-based ISA, the primary operand is stored in:

a) Memory
b) Cache
c) The accumulator register
d) A stack

Answer: c) The accumulator register

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11. Which of the following ISAs uses a large number of general-purpose registers?

a) CISC
b) RISC
c) VLIW
d) SIMD

Answer: b) RISC

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12. In VLIW (Very Long Instruction Word) architecture, how are instructions typically executed?

a) Sequentially
b) In parallel
c) Using pipelining
d) Using a single execution unit

Answer: b) In parallel

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13. Which of the following architectures is designed to minimize the complexity of hardware?

a) CISC
b) RISC
c) VLIW
d) EPIC

Answer: b) RISC

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14. What is the primary purpose of addressing modes in an ISA?

a) To control data flow
b) To specify operands
c) To manage memory access
d) To allocate cache

Answer: b) To specify operands

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15. Which type of instruction in an ISA moves data from one location to another?

a) Arithmetic instruction
b) Data transfer instruction
c) Logical instruction
d) Control instruction

Answer: b) Data transfer instruction

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16. What type of addressing mode uses the actual memory address of the operand?

a) Immediate addressing
b) Register addressing
c) Direct addressing
d) Indirect addressing

Answer: c) Direct addressing

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17. Which addressing mode uses a constant value as an operand?

a) Immediate addressing
b) Direct addressing
c) Indexed addressing
d) Register addressing

Answer: a) Immediate addressing

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18. In which addressing mode is the effective address of the operand stored in a register?

a) Register addressing
b) Indexed addressing
c) Indirect addressing
d) Immediate addressing

Answer: c) Indirect addressing

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19. What does the term “instruction format” refer to in an ISA?

a) The set of instructions available in the architecture
b) The number of addressing modes
c) The structure and layout of an instruction
d) The sequence of instruction execution

Answer: c) The structure and layout of an instruction

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20. In a RISC architecture, how many clock cycles are typically required for a load/store operation?

a) 1
b) 2
c) 3
d) 4

Answer: a) 1

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21. Which of the following instructions is typically NOT found in a RISC ISA?

a) Load/store
b) Multiply/divide
c) Complex memory-to-memory operations
d) Simple arithmetic

Answer: c) Complex memory-to-memory operations

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22. In a load/store architecture, which of the following is true?

a) All operations are performed directly on memory
b) Only load and store instructions access memory
c) Data can be directly modified in memory without loading
d) Memory-to-memory instructions are frequently used

Answer: b) Only load and store instructions access memory

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23. Which ISA uses variable-length instructions?

a) CISC
b) RISC
c) VLIW
d) EPIC

Answer: a) CISC

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24. In x86 architecture, which addressing mode is used when an operand’s memory location is specified by a base register and an offset?

a) Indexed addressing
b) Immediate addressing
c) Direct addressing
d) Indirect addressing

Answer: a) Indexed addressing

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25. Which type of ISA architecture typically supports instructions that can combine arithmetic and memory operations?

a) RISC
b) CISC
c) VLIW
d) EPIC

Answer: b) CISC

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26. In RISC architecture, which of the following is a common feature of instruction execution?

a) Variable-length instructions
b) Microcode interpretation
c) Single-cycle instruction execution
d) Complex addressing modes

Answer: c) Single-cycle instruction execution

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27. What is the main function of the control unit in an ISA?

a) Manage data transfer
b) Execute instructions
c) Decode and execute instructions
d) Perform arithmetic operations

Answer: c) Decode and execute instructions

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28. In an ISA, which component interprets machine instructions?

a) Control unit
b) Arithmetic Logic Unit (ALU)
c) Memory
d) Registers

Answer: a) Control unit

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29. Which ISA type is more likely to use pipelining for improving performance?

a) RISC
b) CISC
c) Stack-based
d) VLIW

Answer: a) RISC

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30. What type of instructions does a RISC architecture typically emphasize?

a) Complex operations
b) Fixed-length instructions
c) Variable-length instructions
d) Memory-to-memory operations

Answer: b) Fixed-length instructions

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31. The main advantage of a VLIW architecture is:

a) Efficient branch handling
b) Increased parallelism
c) Variable instruction size
d) Fewer general-purpose registers

Answer: b) Increased parallelism

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32. Which of the following is true for CISC architecture?

a) Many instructions are executed in a single clock cycle
b) Few addressing modes are available
c) Instructions are complex and variable in length
d) A small number of general-purpose registers are used

Answer: c) Instructions are complex and variable in length

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33. Which of the following instructions controls the flow of a program in an ISA?

a) Data transfer instruction
b) Control instruction
c) Arithmetic instruction
d) Logical instruction

Answer: b) Control instruction

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34. Which type of ISA architecture typically uses simpler hardware design and instructions?

a) CISC
b) RISC
c) VLIW
d) EPIC

Answer: b) RISC

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35. Which type of instruction in an ISA performs logical AND, OR, and NOT operations?

a) Arithmetic instruction
b) Logical instruction
c) Control instruction
d) Data transfer instruction

Answer: b) Logical instruction

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36. What is the main difference between CISC and RISC architectures?

a) CISC uses more complex instructions
b) RISC uses variable-length instructions
c) RISC uses microcode to control execution
d) CISC executes instructions in a single clock cycle

Answer: a) CISC uses more complex instructions

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37. In which type of instruction set are load and store operations typically separated from arithmetic operations?

a) CISC
b) VLIW
c) RISC
d) EPIC

Answer: c) RISC

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38. The main advantage of using fewer instructions in a RISC architecture is:

a) Higher complexity
b) Faster execution
c) Larger instruction size
d) More addressing modes

Answer: b) Faster execution