Patent ID: 6184806
Filing Date: 2001-02-06
Classification: G11B,H03M

Abstract:
Within a magnetic recording channel, a method for encoding a sequence of 32-bit digital data words into a sequence of 33-bit code words in accordance with predetermined minimum zero run length (d) and predetermined maximum zero run length (k) for recording upon a magnetic data storage medium, comprising the steps of:dividing a present 32-bit digital data word into eight four-bit data sub-words,determining whether any of the eight four-bit sub-words are composed entirely of zeros as a code violation,generating a 33-bit code word corresponding to the present 32-bit digital data word by forming eight code sub-words, wherein a first code sub-word at a predetermined location is provided with a fifth bit as a first control bit, and wherein each data sub-word not containing a code violation is mapped unchanged to a code sub-word, and wherein any data sub-word found to contain a code violation is identified by the fifth control bit and by other predefined bit positions of the code word such that the 33-bit code word has a maximum zero run length (k) not exceeding six.