Error correction method and apparatus

An error correction system for correcting multiple randomly located symbol errors recorded on a rotating magnetic disk medium, the disk medium having formatted sectors with data fields interdispersed therein, the system having a data field error correction function operable to correct up to t(t>l) random symbol errors on-the-fly per codeword of each data field of a formatted sector (data block), the system comprising:

• a first interface coupled to the magnetic storage system;
• a second interface coupled to a host;
• a multi-purpose data buffer coupled between said first and second interfaces for storing a varying number of uncorrected and corrected data blocks;
• hardware circuitry for read-modify-write operations performed on said data buffer;
• each of said data blocks while transferred from said first interface to said second interface being affected by at least the steps of:
• i) a first transfer of said uncorrected data blocks from said first interface to said data buffer,
• ii) said uncorrected data blocks within said data buffer corrected to form corrected data blocks, and
• iii) a second transfer of said corrected data blocks from the data buffer to said second interface;
• performance of the three steps of said first transfer of uncorrected data blocks and said correction of uncorrected data blocks and said second transfer of corrected data blocks is asynchronous in time relative to each other and at times executed simultaneously on different sectors in an asynchronously overlapped manner wherein the number of said steps being asynchronously overlapped at any point in time varies from zero to three.

An error correction system for correcting multiple randomly located symbol errors recorded on a rotating magnetic disk medium, the disk medium having formatted sectors with data fields interdispersed therein, the system having a data field error correction function operable to correct up to three integer number of random symbols errors on-the-fly per codeword of each data field of a formatted sector (data block), the system comprising:

• a first interface coupled to the magnetic storage system;
• a second interface coupled to a host;
• a multi-purpose data buffer coupled between said first and second interfaces for storing a varying number of uncorrected and corrected data blocks;
• hardware circuitry for read-modify-write operations performed on said data buffer;
• each of said data blocks while transferred from said first interface to said second interface being affected by at least the steps of,
• i) a first transfer of said uncorrected data blocks from said first interface to said data buffer,
• ii) said uncorrected data blocks within said data buffer corrected to form corrected data blocks, and
• iii) a second transfer of said corrected data blocks from the data buffer to said second interface;
• performance of the three steps of said first transfer of uncorrected data blocks and said correction of uncorrected data blocks and said second transfer of corrected data blocks is asynchronous in time relative to each other and at times executed simultaneously on different sectors in an asynchronously overlapped manner wherein the number of said steps being asynchronously overlapped at any point in time varies from zero to three.

An error correction system for correcting multiple randomly located symbol errors recorded on a rotating magnetic disk medium, the disk medium having formatted sectors with data fields interdispersed therein, the system having a data field error correction function operable to correct up to two integer number of random symbol errors on-the-fly percodewordd of each data field of a formatted sector (data block), the system comprising:

• a first interface coupled to the magnetic storage system;
• a second interface coupled to a host;
• a multi-purpose data buffer coupled between said first and second interfaces for storing a varying number of uncorrected and corrected data blocks;
• hardware circuitry for read-modify-write operations performed on said data buffer;
• each of said data blocks while transferred from said first interface to said second interface being affected by at least the steps of,
• i) a first transfer of said uncorrected data blocks from said first interface to said data buffer,
• ii) said uncorrected data blocks within the data buffer corrected to form corrected data blocks, and
• iii) a second transfer of said corrected data blocks from the data buffer to said second interface;
• performance of the three steps of said first transfer of uncorrected data blocks and said correction of uncorrected data blocks and said second transfer of corrected data blocks is asynchronous in time relative to each other and at times executed simultaneously on different sectors in an asynchronously overlapped manner wherein the number of said steps being asynchronously overlapped at any point in time varies from zero to three.