ALU 101 Carry and Overflow 2

Question 1

Overflow in signed binary arithmetic occurs when:

Accepted Answer

The result cannot be represented in the given number of bits

Answer

The result is negative

Answer

A carry-out is generated

Answer

Both operands have the same sign

Question 2

What does the ALU's carry flag (C flag) indicate?

Accepted Answer

An unsigned carry-out or borrow from the most significant bit

Answer

A signed overflow

Answer

A zero result

Answer

A parity error

Question 3

Can overflow and carry both be set at the same time in a single ALU addition?

Accepted Answer

Yes, they can occur independently

Answer

No, they are mutually exclusive

Answer

Only in floating-point units

Answer

Only in subtraction

Question 4

Adding two positive signed numbers yields a negative result. This is an example of:

Accepted Answer

Signed overflow

Answer

Carry propagation

Answer

Unsigned overflow

Answer

Arithmetic underflow

Question 5

In 4-bit two's complement, what is the result of 0111 + 0001?

Accepted Answer

1000 with overflow

Answer

0111 with carry

Answer

1000 with no overflow

Answer

1001 with overflow

Question 6

What hardware mechanism detects signed overflow in an ALU adder?

Accepted Answer

XOR of the MSB carry-in and carry-out

Answer

AND of all carry bits

Answer

Parity check on the result

Answer

Comparing operand signs with the result sign