| 摘要 |
PURPOSE: A calculator performing an overflow manipulation is provided to output a result similar to a desired result when overflow occurs. CONSTITUTION: The calculator includes a plurality of input registers(12,13), an arithmetic logic unit(11), an overflow bit(16), a carry decreasing unit(14), a carry increase flag(17) and a result register(15). The arithmetic logic unit performs a predetermined calculation on the data received by the input registers and outputs the result. The overflow bit is activated when the overflow occurs on the result of the arithmetic logic unit. The carry decreasing unit(14) decreases the carry of the output of the arithmetic logic unit on every activation of the overflow bit and stores the overflow bit on the most significant bit. The carry increase flag performs down-counting on every activation of the overflow bit. The result register shifts-up the result stored in the carry decreasing unit(14) by the bit number counted at the carry increase flag and stores the result.
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