A = x B = x CARRY = x SUM = x
A = 0 B = 0 CARRY = x SUM = x
A = 0 B = 0 CARRY = 0 SUM = 0
A = 1 B = 0 CARRY = 0 SUM = 0
A = 1 B = 0 CARRY = 0 SUM = 1
A = 1 B = 1 CARRY = 0 SUM = 1
A = 1 B = 1 CARRY = 1 SUM = 0
A = 0 B = 1 CARRY = 1 SUM = 0
A = 0 B = 1 CARRY = 0 SUM = 1
A = 0 B = 0 CARRY = 0 SUM = 1
A = 0 B = 0 CARRY = 0 SUM = 0