摘要 |
<p>A method of, and apparatus for, encoding and decoding a sequence of data bytes to permit correction of bit errors occurring in one byte of the sequence, or two bytes providing that the two incorrect bytes can be identified (for example if the bytes show parity failure). Each data byte of the sequence comprises data bits and one parity check bit. To encode the sequence of data bytes two <<Code C>> code bytes are determined from the data bytes, according to predetermined relationships, the data bytes and code bytes together forming an encoded data block. Also, there is provided a method of, and apparatus for, encoding and decoding a bundle of data blocks to permit correction of a number bit errors occurring in bytes of the bundle. (Conceptually, the bundle of data blocks comprises a stack of data blocks, one positioned under another to form a two dimensional array of bytes.) Data block bundle encoding consists of separately encoding rows (i.e. horizontal encoding) and columns or pairs of colums (i.e. vertical encoding) of bytes of the bundle array with two <<Code C>> code bytes.</p> |