CIRCUIT FOR ERROR CORRECTING AND DECODING

PROBLEM TO BE SOLVED: To provide an error correcting and decoding circuit in which the circuit scale of the part for operating for an error position and error data can be reduced concerning the error correcting and decoding circuit. SOLUTION: This error correcting and decoding circuit is provided with a syndrome arithmetic circuit for calculating a syndrome from input data, a polynomial arithmetic circuit for using the syndrome to calculate an error position polynomial and an error numerical value polynomial, and a chain retrieval circuit for using the output of the polynomial arithmetic circuit to calculate an error position and error data. A register for storing the coefficients of the error position polynomial and the error numerical value polynomial outputted by the polynomial arithmetic circuit is arranged between the polynomial arithmetic circuit and the chain retrieval circuit, and the chain retrieval circuit reads the coefficients of the two polynomials and performing chain retrieval in deciding the acceptance/rejection of error correction in one frame and in specifying error data.