Patent ID: 6754870
Filing Date: 2004-06-22
Classification: G06F,H03M

Abstract:
A CRC operation unit comprising:generating polynomial supply means for holding data representing a generating polynomial and selectively outputting the data representing a generating polynomial or zero data of which all bits have a value of 0; operation data supply means for outputting operation data to be subjected to CRC operation; and arithmetic and logic operation means for performing exclusive OR operation between the data representing a generating polynomial or the zero data and the operation data, wherein the generating polynomial supply means selects the data representing a generating polynomial or the zero data depending on a value of the most significant bit (MSB) of operation results from the arithmetic and logic operation means, and the operation data supply means outputs, as the operation data, data composed of: values of bits in lower order than the MSB of the operation results from the arithmetic and logic operation means as values of higher-order bits of the operation data; and a value of the MSB of unprocessed data to be subjected to CRC operation as a value of the LSB of the operation data.