In an 8085 microprocessor system, the following program starts at location 0100H

LXI SP 00FF

LXI H 0701

MVI A 20H

SUB M

The content of the accumulator when the program counter reaches 0107 H is

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This question was previously asked in

ESE Electrical 2013 Paper 2: Official Paper

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Answer 1

Concept:

LXI is a 3 Byte Instruction

MVI is a 2 Byte Instruction

SUB is a 1 Byte Instruction

Analysis:

0100 LXI (Op Code Fetch)

0101 -- FF (Lower Order Bits)

0102 -- 00 (Higher Order Bits)

0103 -- LXI (Op Code Fetch)

0104 -- 01

0105 -- 07

0106 -- MVI A (Op Code Fetch)

0107 -- 20 H

∴ The content of the accumulator when the program counter reaches 0107 H is 20 H