In 8051, the accumulator register contains 80H and B register contains 8FH. The content of the accumulator and status of the carry flag after the addition operation are respectively

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ESE Electronics Prelims 2021 Official Paper
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  1. 0FH, 1
  2. 10FH, 0
  3. FFH, 1
  4. 10FH, 1

Answer (Detailed Solution Below)

Option 1 : 0FH, 1
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Detailed Solution

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The correct answer is option 1.

Key PointsA= 80H 
B= 8FH
[A] + [B] = 80H + 8FH = 1 0FH

          1000 0000

   +     1000 1111 

------------------------------

      1   0000 1111  (1 0FH)

-----------------------------
But accumulator is an 8-bit register
Accumulator = 0FH
carry flag= 1

Hence the correct answer is 0FH, 1.

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