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8. The Overfow Output

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    INPUTS OUTPUTS
    Asign Bsign CARRY IN CARRY OUT SUMsign OVERFLOW
    0 0 0 0 0 ?
    0 0 1 0 1 ?
    0 1 0 0 1 ?
    0 1 1 1 0 ?
    1 0 0 0 1 ?
    1 0 1 1 0 ?
    1 1 0 1 0 ?
    1 1 1 1 1 ?

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  • Full adder truth table for the sign bit can be extended to include new output which indicates if overfow condition has occured.

  • Our task is to populate the OVERFLOW column with corresponding values.

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