| 摘要 |
PURPOSE:To prevent a result of addition from being varied by an input data, by setting an addition output to a positive maximum value or a negative maximum value, in case an overflow state or an underflow state has been decided. CONSTITUTION:In an adding circuit 1, an input data of the uppermost bit is added, and also, based on a result of its addition and the input data to the uppermost bit, whether an addition output overflows or underflows is decided by a deciding circuit 3. Subsequently, in the case of corresponding to the overflow, the addition output is set to a positive maximum value, and in the case of corresponding to the underflow, the addition output is set to a negative maximum value. In such a way, the generation of the overflow or the underflow can be prevented, and a variation of the addition output can be prevented. |
