GATE Overflow | Digital Logic | Test 1 | Question: 15

Question

The addition of 4 bits two complement binary numbers $1101$ and $0100$ results in

• A. 0001 and an overflow
• B. 1001 and no overflow
• C. 0001 and no overflow
• D. 1001 and an overflow

Answer 1

Overflow cannot occur when number under addition are of opposite sign

Here one number is +ve and another is -ve

Now we perform 2's compliment arithmetic

 1101 + 0100 == 10001 discard carry as in 2's compliment rule

Final answer 0001 no overflow

Comments

how do you know whether it is 1’s compliment addition or 1’s compliment addition