Matching Addressing Modes with Instructions

This question requires matching specific assembly language instructions (LIST-I) with their corresponding addressing modes (LIST-II).

Addressing Mode Analysis

• A. Immediate Addressing Mode: The data is part of the instruction itself.
  • Example: $MOV DPTR,#4521H$. Here, $#4521H$ is the immediate data being loaded into the DPTR register.
  • Matches with: II. MOV DPTR,#4521H
• B. Indexed Addressing Mode: The effective address is calculated by adding a base register (like DPTR) and an index register (like A). This mode is typically used for look-up tables.
  • Example: $MOVC A,@A+DPTR$. The address is computed as the sum of the accumulator (A) and DPTR.
  • Matches with: III. MOVC A,@A+DPTR
• C. Register Addressing Mode: The operand is directly located in a CPU register specified by the instruction.
  • Example: $MOV A, R0$. The content of register R0 is moved to register A.
  • Matches with: IV. MOV A, R0
• D. Register Indirect Addressing Mode: The instruction specifies a register that contains the *address* of the operand, not the operand itself.
  • Example: $MOV A,@R0$. The data is fetched from the memory location whose address is currently stored in register R0.
  • Matches with: I. MOV A,@R0

Correct Matching

Based on the analysis:

• A matches with II
• B matches with III
• C matches with IV
• D matches with I

This corresponds to the matching: A-II, B-III, C-IV, D-I.