An input device is interfaced with Intel 8085A microprocessor

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An input device is interfaced with Intel 8085A microprocessor as memory mapped I /O. The address of the device is 2500H. In order to input data from the device to accumul at or, the sequence of instructions will be

1. LXI H,2500H
  MOV A,M
2. LXI H,2500H
  MOV M,A
3. LHLD 2500H
  MOV A,M
4. LHLD 2500H
  MOV M,A

Correct Option: A

L × 1 H, 2500H: the data 2500H is loaded into HL pair
MOV A,M: the content of memory location whose address is in HL pair, is moved to accumulator. So finally input data from device is moved to accumulator.

LXI	H,2500H
MOV	A,M

LXI	H,2500H
MOV	M,A

LHLD	2500H
MOV	A,M

LHLD	2500H
MOV	M,A