Patent ID: 7181483

Claim:
An Euclidean calculating unit comprising: a first storage unit storing, in an operation for serially deriving coefficients of an error evaluator polynomial indicating an error amount of received data, first data corresponding to the coefficients of said error evaluator polynomial, said first storage unit capable of shifting said first data; a second storage unit storing, in an operation based on Euclidean algorithm for serially deriving coefficients of an error locator polynomial indicating an error position of said received data, second data corresponding to the coefficients of said error locator polynomial, said second storage unit capable of shifting said second data; a control unit based on a syndrome polynomial corresponding to said received data for performing initial setting of the data stored in said first and second storage units and controlling processing of said Euclidean algorithm; a multiplier provided commonly to said first and second storage units for performing multiplication on a Galois field based on said Euclidean algorithm; a selector controlled by said control unit for controlling data transfer between said multiplier and said first and second storage units; and a logic operation unit for performing a logical operation on the data stored in said first and second storage units based on said Euclidean algorithm.