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The contents of Register (BL) and Register (AL) of 8085 microprocessor are 49H and 3AH respectively. The contents of AL, the status of carry flag (CF) and sign flag (SF) after executing 'SUB AL, BL' assembly language instruction, are

  1. AL=0FH; CF=1; SF=1
  2. AL=F0H; CF=0; SF=0
  3. AL=F1H; CF=1; SF=1
  4. AL=1FH; CF=1; SF=1
in Others by Veteran (431k points) | 2.6k views
0
is it option 3?
0
y some1 named @Psunny is downvoting my questions one after another? :\

2 Answers

+1 vote

 Answer is option C.

AL = F1H, CF = 1,  SF = 1.

by Active (1.2k points)
edited by
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(A) => 3AH => 00111010
(B) => 49H => 01001001
                         ------------------
                          11110001
(A) => F1H
(CY) => 1
(S) => 1

The carry flag is set since the first operand is less than the second operand.
Since the result produces the negative result sign flag is set
by (167 points)

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