Question

Consider the following statements :
A. MOV A, M copies data from memory (pointed by HL) to accumulator

B. LXI H, 2025H loads 2025H into register pair HL

C. STA 2050H stores the accumulator content into memory at address 2050H

D. LDA 2050H loads HL with the contents of memory location at 2050H

Choose the correct answer from the options given below :

• A. A, B, C only
• B. B, C, D only
• C. A, D only
• D. A, C, D only

Hint:

In 8085, the 'M' in instructions always refers to the memory location pointed to by the HL register pair.

Answer 1

The Correct Option is A

Concept:
• The 8085 microprocessor uses various data transfer instructions to move 8-bit or 16-bit data between registers and memory.

Step 1: Evaluate indirect memory transfer (A)
The register 'M' in 8085 instructions refers to the memory location pointed to by the address stored in the HL register pair. MOV A, M correctly moves data from that memory address to the Accumulator. Statement A is Correct.

Step 2: Evaluate immediate register pair loading (B)
LXI stands for Load Register Pair Immediate. LXI H, 2025H loads the 16-bit constant 2025H into the HL pair. Statement B is Correct.

Step 3: Evaluate direct memory storage (C)
STA stands for Store Accumulator Direct. It copies the content of the Accumulator into the memory location specified by the 16-bit address in the instruction. Statement C is Correct.

Step 4: Evaluate direct memory loading (D)
LDA stands for Load Accumulator Direct. It copies the content of the specified memory address into the Accumulator, not the HL pair. To load HL from memory, one would use LHLD. Statement D is Incorrect.