摘要 |
The coded data (12) on the record carrier (10) and the method for encoding such data (12) in tracks (14) provide a relatively simple and yet very effective means for making the data record carrier (10), and particularly the data (12) recorded thereon, highly tolerant of errors such as "burst errors" where one or more spots of data on the data record carrier (10) are obliterated. The data (12) is recorded on the data record carrier (10) in arcuate nested tracks (14), each track (14) comprising a stream of data bits. The stream of data bits includes an encoded front track address (32) and encoded back track address (44) with coded groups or so-called Hamming type coded groups (52) of data bits therebetween each of which can comprise 96 or 105 data bits. Error correction is provided by including in the coded groups data words which include a data byte and a field of parity bits, typically an eight bit data byte followed by a four bit parity field. Also a cyclic redundancy checksum byte is provided in the group as a further check of the data therein. Further, this data is multiplexed. Additionally, one or two redundant groups are provided in each track (14) for recreating missing groups and a cyclic redundancy checksum field is provided for error detection in each track (14).
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