There is a register within the processor that has a variety of flags that it can use to signal the results from various operations. We will consider the following registers.

• The carry flag is used to indicate when an arithmetic carry or borrow has been generated out of the MSB after an arithmetic operation.

• The zero flag is used to check the result of an arithmetic operation. It is set to 1, or true, if an arithmetic result is zero, and reset (to 0) otherwise.

• The sign flag used to indicate whether the result of the last mathematical operation resulted in a negative or positive number. Is set to the value of the MSB (the left hand bit).

• Overflow flag is set if a result is too large a positive number or too small a negative number (excluding sign-bit) to fit in a register, cleared otherwise.

An overflow occurs when the computer attempts to handle a number that is too large for it. 

• Every computer has a range of values that it can represent. 

• If during execution of a program it arrives at a number outside this range, it will experience an overflow error.

In computer processors, the overflow flag is usually a single bit register used to indicate when an arithmetic overflow has occurred in an operation.

We will calculate the value stored in an 8 bit register as a result of adding the 8-bit two’s complement numbers 1110 1000 and 0001 1000. 

State the value stored in an 8 bit register as a result of adding the 8-bit two’s complement numbers 1110  0111 + 0110 0011 (-25 + 99) = 74 (0100 1010)