Some machines have a special flag register which contains status bits. These bits often include the carry and overflow bits. Describe the difference between the functionality of these two bits and give an example of an arithmetic operation that would lead to them being set to different values.

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The Answer is The carry flag is set when arithmetic operation results in generating a carry bit out of the most significant bit position of its operand. The overflow flag is set when an arithmetic operation results in generating a carry bit out of the most significant bit position of the physical register which holds its operand. An overflow means that the register size is not big enough to hold the result of the current arithmetic operation while a carry just indicates that the resulting value's most significant bit position is higher (or lower in case of a borrow) than its operand by a bit position. When we add two integers: 0x0100 and 0x0110 which are held in 16-bit registers, the result 0x1010 generates a carry but not a overflow bit.

Some Machines Have a Special Flag Register Which Contains Status