Full adder/subtractor circuit employing exclusive OR logic

摘要

A binary full adder/subtractor circuit includes an exclusive OR gate operating upon augend/minuend and addend/subtrahend binary input signals. The sum/difference output from the circuit is the carry/borrow input signal or its inverse depending upon the output state of the exclusive OR gate. The carry/borrow output of the circuit comprises either the carry/borrow input or the addend/subtrahend input, as determined by the output of the exclusive OR gate and by an operation (sum/difference) specifying input signal.