Error counting mechanism
AssigneeMaxtor Corporation
InventorLih-Jyh Weng
Life of this patent
Estimating the term…
Abstract
A mechanism for determining a number of errors in an error correction code codeword is presented. The mechanism obtains the degree of an error locator polynomial associated with syndromes generated for the codeword without determining coefficients of the error locator polynomial. The degree is identified as the number of errors. The degree is determined from the syndromes using a Euclidean process which determines the degree without finding the coefficients. Alternatively, the degree is determined by forming a trapezoid-shaped matrix from the syndrome values and finding the rank of that matrix.
Claims23
A method of determining a number of errors in an error correction codeword comprising:
- determining from the error correction codeword a syndrome polynomial associated with an error locator polynomial of a degree and having error locator polynomial coefficients;
- operating on the syndrome polynomial to determine the degree without determining the error locator polynomial coefficients;
- and
- identifying the degree as the number of errors in the error correction codeword.
A method of testing a storage medium having a codeword stored thereon, comprising:
- reading the codeword from the storage medium;
- generating syndrome values for the codeword;
- obtaining from the syndrome values a degree of an error locator polynomial without computing the coefficients of the error locator polynomial, the degree corresponding to the number of errors;
- comparing the number of errors to an error threshold;
- and
- determining if the number of errors exceeds the error threshold.
A method of testing a storage medium having codewords stored thereon, comprising:
- reading the codewords from the storage medium;
- generating syndrome values for the codewords;
- obtaining from the syndrome values a degree of an error locator polynomial without computing the coefficients of the error locator polynomial, the degree corresponding to the number of errors;
- comparing the number of errors to an error threshold;
- and
- determining, for each of the codewords, if the number of errors exceeds the error threshold.
A decoder for processing a codeword read from a storage medium comprising:
- a syndrome generator for producing a syndrome polynomial from the codeword, the syndrome polynomial being associated with an error locator polynomial have a degree and coefficients;
- and
- an error locator polynomial degree determiner coupled to the syndrome generator for determining from the syndrome polynomial the degree of the error locator polynomial without ion determining the coefficients of the error locator polynomial, and indicating the degree as the number of errors in the codeword.
A data storage system comprising:
- a storage device having a codeword stored in a location thereon;
- a read/write controller coupled to the storage device for reading the codeword from the storage device;
- a decoder for generating from the codeword a syndrome polynomial, the syndrome polynomial being associated with an error locator polynomial of a degree and coefficients, and for determining from the syndrome polynomial the degree of the error locator polynomial without determining the coefficients of the error locator polynomial, and for indicating the degree as the number of errors in the codeword to the read/write controller.
A test apparatus for testing a storage medium having codewords stored thereon comprising:
- a read/write controller coupled to storage medium and the error count unit for reading codewords from the storage medium;
- an error count unit for generating from each of the codewords a syndrome polynomial, the syndrome polynomial being associated with an error locator polynomial of a degree and coefficients, for determining from the syndrome polynomial the degree of the error locator polynomial without determining the coefficients of the error locator polynomial, and for indicating the degree as the number of errors in to the read/write controller;
- and
- a unit for comparing the number of errors to an error threshold to determine if the number of errors exceeds the error threshold.
Dependencies are inferred from the claim text.