This set of Addressing Modes MCQ covers important concepts of Computer Organization and Architecture (COA) related to immediate addressing, direct addressing, indirect addressing, register addressing, relative addressing, and effective address calculation. Useful for GATE, IBPS IT Officer, university semester exams, and other technical competitive examinations.
Topic: Computer Organization & Architecture (COA) – Addressing Modes | Set: 1
Difficulty: Easy to Medium | Total Questions: 15
Addressing Modes MCQ
Q1. In which addressing mode is the operand actually present in the instruction itself?
- A. Direct Addressing
- B. Immediate Addressing
- C. Register Addressing
- D. Indirect Addressing
View Answer & Explanation
Answer: B
Explanation: Immediate addressing uses a constant value as the operand within the instruction.
Q2. Which addressing mode specifies the register that contains the operand?
- A. Register Addressing
- B. Register Indirect Addressing
- C. Immediate Addressing
- D. Implicit Addressing
View Answer & Explanation
Answer: A
Explanation: In Register mode, the data is stored in a CPU register rather than memory.
Q3. In Direct Addressing mode, the address field of the instruction contains the:
- A. Operand
- B. Pointer to the operand
- C. Effective Address of the operand
- D. Value to be added to the PC
View Answer & Explanation
Answer: C
Explanation: The instruction explicitly provides the memory address where the data is located.
Q4. Which addressing mode is most suitable for defining constants in a program?
- A. Relative
- B. Indexed
- C. Immediate
- D. Displacement
View Answer & Explanation
Answer: C
Explanation: Immediate mode is the fastest way to load fixed numerical constants.
Q5. In Register Indirect addressing, the Effective Address (EA) is:
- A. The value stored in the instruction
- B. The content of the register
- C. The content of the memory location
- D. The PC value
View Answer & Explanation
Answer: B
Explanation: The register acts as a pointer, holding the memory address of the operand.
Q6. Which addressing mode is used in instructions like ‘PUSH’ or ‘POP’?
- A. Direct
- B. Register
- C. Stack Addressing
- D. Relative
View Answer & Explanation
Answer: C
Explanation: Stack addressing implicitly uses the Stack Pointer (SP) to reference the top of the stack.
Q7. The mode where the address of the operand is determined by adding a constant to the Program Counter (PC) is:
- A. Base Register Addressing
- B. Indexed Addressing
- C. PC-Relative Addressing
- D. Indirect Addressing
View Answer & Explanation
Answer: C
Explanation: PC-Relative mode calculates the address based on the current instruction’s location.
Q8. Which addressing mode does not require a memory reference to fetch the operand?
- A. Direct
- B. Indirect
- C. Register
- D. Indexed
View Answer & Explanation
Answer: C
Explanation: Register addressing accesses internal CPU registers, avoiding slower memory cycles.
Q9. In a 2-address instruction, the “Implied” addressing mode is often used for:
- A. Accumulator-based operations
- B. Stack-based operations
- C. Memory-to-memory moves
- D. Subroutine calls
View Answer & Explanation
Answer: A
Explanation: Implied mode assumes a specific register (like the Accumulator) is the target without naming it.
Q10. Which mode is most efficient for accessing global variables with fixed memory locations?
- A. Direct Addressing
- B. Relative Addressing
- C. Immediate Addressing
- D. Indirect Addressing
View Answer & Explanation
Answer: A
Explanation: Direct addressing points straight to the specific memory cell assigned to the variable.
Q11. The ‘effective address’ is defined as:
- A. The address of the next instruction
- B. The actual memory address of the operand
- C. The address of the CPU register
- D. The offset value
View Answer & Explanation
Answer: B
Explanation: EA is the final physical address used to access the data in main memory.
Q12. Which mode is represented by the syntax MOV R1, #50?
- A. Direct
- B. Immediate
- C. Indexed
- D. Relative
View Answer & Explanation
Answer: B
Explanation: The ‘#’ symbol typically denotes an immediate constant value.
Q13. Auto-increment addressing is a special case of:
- A. Indexed Addressing
- B. Register Indirect Addressing
- C. Direct Addressing
- D. Immediate Addressing
View Answer & Explanation
Answer: B
Explanation: It uses a register as a pointer and automatically increments it after access.
Q14. How many memory references are needed to fetch an operand in Direct Addressing?
- A. 0
- B. 1
- C. 2
- D. 3
View Answer & Explanation
Answer: B
Explanation: One memory reference is needed to get the data from the specified address.
Q15. Which mode is best for simple branching or loops?
- A. Relative Addressing
- B. Indirect Addressing
- C. Immediate Addressing
- D. Base-Register Addressing
View Answer & Explanation
Answer: A
Explanation: Relative addressing allows the code to jump to a location relative to the current instruction.
Conclusion
These Addressing Modes MCQ questions help strengthen important concepts of Computer Organization and Architecture (COA) such as effective address calculation, register addressing, immediate addressing, indirect addressing, and relative addressing. These topics are frequently asked in GATE, IBPS IT Officer, university semester exams, and other technical competitive examinations.
For better understanding, practice problems related to effective address calculation, instruction formats, and CPU instruction execution.
Fore theory and concepts, refer to Addressing Modes in Computer Organization.