Q83.Marks: +2.0UGC NET Paper 2: Computer Science 11 March 2023
Match List I with List II
LIST - I
LIST - II
A.
Direct Addressing
I.
MVI A, FFH
B.
Indirect Addressing
II.
MOV A, B
C.
Register Addressing
III.
STA FFFFH
D.
Immediate Addressing
IV.
MOV A, M
Choose the correct answer from the options given below:
1.A - I, B - II, C - III, D - IV
2.A - II, B - III, C - IV, D - I
3.A - III, B - IV, C - II, D - I✓ Correct
4.A - IV, B - III, C - I, D - II
Solution
The correct answer is A - III, B - IV, C - II, D - I
Key Points
In Assembly programming language, there are different types of address modes:
Direct Addressing: Also known as absolute addressing, is when the instruction specifies the memory address of the operand.
Indirect Addressing: The instruction specifies a register that contains the memory address of the operand.
Register Addressing: The instruction specifies the register which contains the operand.
Immediate Addressing: The instruction contains the operand.
Matching each mode with the corresponding example:
Direct Addressing would be "STA FFFFH" because the instruction specifies the exact memory address to store an accumulator.
Indirect Addressing would be "MOV A, M" because the instruction specifies a memory location using an indirect reference which indirectly points to the operand's location.
Register Addressing would be "MOV A, B" because the instruction defines that the value in register B is to be moved to register A.
Immediate Addressing would be "MVI A, FFH" because the instruction contains the data directly (in this case, FFH is the immediate data).
Therefore, the matching is: A - III, B - IV, C - II, D - I
Additional Information
Indexed Addressing Mode: Some architectures provide indexed addressing modes where the final address is calculated by adding a base register and an index value. This is particularly useful in array traversals.
Relative Addressing Mode: The effective address of the operand is generated by adding an offset value from the instruction to the program counter or a base register.
Base Register Addressing Mode: In this mode, a base register holds a base address and the address field of the instruction holds displacement. The effective address is calculated by adding the base address to the displacement.
