Saturating Adder: Unsigned and 2’Complement

• For an unsigned saturating adder, 8 bit:

  • Perform binary addition
  • If Carryout of MSB =1, then result should be a $FF.
  • If Carryout of MSB =0, then result is binary addition result.

• For a 2’s complement saturating adder, 8 bit:

  • Perform binary addition
  • If Overflow = 1, then:
    • If one of the operands is negative, then result is $80
    • If one of the operands is positive, then result is $7f
  • If Overflow = 0, then result is binary addition result.

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