Explain please What are the overflow and carry flags in the

What are the overflow and carry flags in the following operations in a four-bit system?

Solution

As, In binary addition:

1+0=1

0+0=0

0+1=1

1+1=0 carry 1

For 4 bit addition, if answer is greater than 4 bit then it is the case of overflow.

In binary subtraction,

1-0=1

0-0=0

1-1=0

0-1=0 borrow 1

For 4 bit, if result is less than 4 then this is the case of overflow.

	Carry	Overflow
1100 + 1010	1	1
1101 - 1100	0	0
1100 + 1010	1	1
0100 - 0110	borrow 1	underflow 1
0100 + 0010	0	0
0100 + 0110	1	0
1100 - 0110	borrow 1	0