INVERSE ELEMENT ARITHMETIC UNIT ON FINITE FIELD AND METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To make an inverse element arithmetic performable at a high speed by reducing the number of memory accesses. ;SOLUTION: This inverse element arithmetic unit 10 is provided with a memory 19 storing a value performing an inverse element arithmetic and the value of the result of a concerned inverse element arithmetic, a square calculating circuit 11, a multiplying circuit 12, a first selector 16 selectively outputting one value of the value stored in the memory 19, a value from the square calculating circuit 11 and a value from the multiplying circuit 12, a second selector 17 selectively outputting either the value stored in the memory 19 or the value from the circuit 12, a third selector 18 selectively outputting either of inputted values to the circuit 12, a first register 13 which stores a value from the first selector 16 and outputs it to the circuit 11, the circuit 12 and the memory 19, a second register 14 which stores a value to be outputted from the second selector 17 and outputs it to the third selector 18 and a third register 15 which preserves a value to be outputted from the memory 19 during the inverse element arithmetic and outputs it to the selector 18.;COPYRIGHT: (C)2001,JPO