EP0110367A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Coded data on a record carrier and method for encoding same
Assignee: NEWS LOG INTERNATIONAL Inc
•
Filing: 1983-11-28
•
Granted: —
•
Expires: 2003-11-28
Abstract
Abstract 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) are 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).
Inventors
- 👤 Alan A. Jewer
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 07:01
CPC Classifications
G; G06; G06K; G06K19/00; G06K19/06; G06K19/06009; G06K19/06046; G06K19/06075; G06K19/06037; G11; G11B; G11B20/00; G11B20/10; G11B20/12; G11B20/14; G11B20/1403; G11B20/18; G11B20/1833; G11B27/00; G11B27/10; G11B27/19; G11B27/28; G11B27/30; G11B27/3027; G11B7/00; G11B7/002; G11B7/0033; G11B7/007; G11B7/013
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
81 words
A method for encoding digital data which is recorded in tracks on a substrate to form a data record carrier with each track having a front track address section, a back track address section and coded groups therebetween, characterized in that said method of encoding provides error correction and includes the step of: providing in each coded group (52) a plurality of coded words, each work comprising a byte of data bits and a field of parity bits for error correction.
Claim 2
Independent Claim
81 words
A method for encoding digital data which is recorded in tracks on a substrate to form a data record carrier with each track having a front track address section, a back track address section and coded groups therebetween, characterized in that said method of encoding provides error correction and includes the step of: providing in each coded group (52) a plurality of coded words, each work comprising a byte of data bits and a field of parity bits for error correction.
Claim 3
Dependent Claim
28 words
The method of claim 1 characterized in that said coded group (52) also includes a cyclic redundancy checksum word formed by invoking a residue add and shift technique.
Claim 4
Dependent Claim
47 words
The method of claim 2 characterized in that said cyclic redundancy checksum word is formed by exclusive ORing the eight least significant bits with the eight most significant bits of an original 16 bit cyclic redundancy checksum word to obtain the eight bit cyclic redundancy checksum byte.
Claim 5
Dependent Claim
50 words
The method of claim 1, 2 or 3 characterized in that said coded group (52) comprises seven data words each comprising an eight bit data byte and a four bit parity field and an eighth word comprising an eight bit cyclic redundancy checksum byte and a four bit parity field.
Claim 6
Independent Claim
21 words
The method of any one of claims 1-4 characterized in that said data bits in each coded group (52) are multiplexed.
Claim 7
Dependent Claim
67 words
The method of claim 5 characterized in that said multiplexing is achieved by recording the data bits in a stream which defines columns of data bits which are arran g eable in an array or matrix to form data words in rows across the array or matrix of the adjacent columns of data bits retrieved from the data record carrier (10) in the field of the array.
Claim 8
Independent Claim
106 words
The method of any one of claims 1-6 characterized in that each track (14) is provided with at least one cyclic redundancy checksum field section obtained by invoking a CCITT polynomial for all the data bits in the coded groups which invoking consists of an application of a residue add and shift technique to all the data bits, the result cf which is a cyclic redundancy checksum word, such as a 16-bit cyclic redundancy checksum word, whereby the residue add and shift technique can be applied to the data retrieved from the coded groups (52) and compared with the cyclic redundancy checksum word to detect errors.
Claim 9
Independent Claim
73 words
The method of any one of claims 1-7 characterized in that each track (14) is provided with at least one redundant coded group which is the result of sequential exclusive ORing, residue add, or comparing, of all the data bits in the coded-groups (52) such that if a coded group (52) is found to be missing, the exclusive ORing of the groups retrieved and the redundant group will result in the missing group.
Claim 10
Dependent Claim
93 words
The method of claim 8 characterized in that two redundant coded groups are provided in each track (14), one such redundant group being positioned on the track (14) at the beginning of the coded groups (52) and being a resultant redundant group of all the odd or even coded groups (52), and the second such redundant group being positioned in the.track (14) at the end of the coded groups (52) and being a resultant redundant group of all the even or odd coded groups (52) whereby two lost adjacent groups can be recreated.
Claim 11
Independent Claim
78 words
The method of any one of claims 1-7 characterized in that each track address (32, 44) has half the data bits of the bit positions in a front track address section (32) and the address is placed on the track in proper order in the first half of the bit positions and the second half of the bit positions of the address section are filled with the inversion or compliment of the track address (32) in reverse order.
Claim 12
Dependent Claim
25 words
The method of claim 10 characterized in that said back track address section (44) is a mirror image of the front track address section (32).
Claim 13
Independent Claim
70 words
The method of any one of claims 1-11 characterized in that two identical cyclic redundancy checksum field sections are provided, one at the beginning of each track (14) and one at the end of each track (14) and each such cyclic redundancy checksum field section is combined with a track address (32, 44) and placed in the front track address section (32) or the back track address section (44) respectively.
Claim 14
Dependent Claim
47 words
The method of claim 12 characterized in that said combined track address byte and cyclic redundancy checksum field byte are each encoded with a parity field, a cyclic redundancy checksum word is formed therefrom to form another data byte and all the resulting data bits are multiplexed.
Claim 15
Dependent Claim
73 words
A data record carrier having digital data encoded in tracks on a substrate, with each track having a front track address section, a back track address section and coded groups therebetween, characterized in that each coded group (52) has error correction encoded therein such that each coded group (52) comprises a plurality of coded words and each word comprises a byte of data bits and a field of parity bits for error correction.
Claim 16
Dependent Claim
73 words
A data record carrier having digital data encoded in tracks on a substrate, with each track having a front track address section, a back track address section and coded groups therebetween, characterized in that each coded group (52) has error correction encoded therein such that each coded group (52) comprises a plurality of coded words and each word comprises a byte of data bits and a field of parity bits for error correction.
Claim 17
Dependent Claim
30 words
The data record carrier of claim 14 characterized in that said coded group (52) also includes a cyclic redundancy checksum word formed by invoking a residue add and shift technique.
Claim 18
Dependent Claim
47 words
The method of claim 15 characterized in that said cyclic redundancy checksum word is formed by exclusive ORing the eight least significant bits with the eight most significant bits of an original 16 bit cyclic redundancy checksum word to obtain the eight bit cyclic redundancy checksum byte.
Claim 19
Dependent Claim
52 words
The data record carrier of claim 14, 15 or 16 characterized in that said coded group (52) comprises seven data words each comprising an eight bit data byte and a four bit parity field and an eighth word comprising an eight bit cyclic redundancy checksum byte and a four bit parity field.
Claim 20
Dependent Claim
21 words
The data record carrier of any one of claims 14-16 wherein said data bits in each coded group (52) are multiplexed.
Claim 21
Dependent Claim
55 words
The data record carrier of claim 18 characterized in that said multiplexing is achieved by recording the data bits in streams which define columns of data bits which are arrangeable in an array or matrix of the adjacent columns of data bits retrieved from the data record carrier (10) in the field of the array.
Claim 22
Dependent Claim
110 words
2 0 . The data record carrier of any one of claims 14-19 characterized in that each track (14) is provided with at least one cyclic redundancy checksum field section obtained by invoking a CCITT polynomial for all the data bits in the coded group (52) which invoking consists of an application of a residue add and shift technique to all the data bits, the result of which is a cyclic redundancy checksum word, such as a 16-bit cyclic redundancy checksum word, whereby the residue add and shift technique can be applied to the data retrieved from the coded groups (52) and compared with the checksum word to detect errors.
Claim 23
Dependent Claim
75 words
The data.record carrier of any one of claims 14-20 characterized in that each track (14) is provided with at least one redundant coded group which is the result of sequential exclusive ORing, residue add, or comparing, of all the data bits in the coded groups (52) such that if a coded group (52) is found to be missing, the exclusive ORing of the groups retrieved and the redundant group will result in the missing group.
Claim 24
Dependent Claim
93 words
The data record carrier of claim 21 characterized in that two redundant coded groups are provided in each track (14), one such redundant group being positioned on the track at the beginning of the coded groups (52) and being a resultant redundant group of all the odd or even coded groups, and the second such redundant group being positioned in the track (14) at the end of the coded groups (52) and being a resultant redundant group of all the even or odd coded groups whereby two lost adjacent groups can be recreated.
Claim 25
Dependent Claim
75 words
The data record carrier of any one of claims 14-22 characterized in that each track address (32, 44) has half the data bits of the bit positions in a track address section and the address is placed on the track (14) in proper order in the first half of the bit positions and the second half of the bit positions are filled with the inversion or compliment of the track address (32) in reverse order.
Claim 26
Dependent Claim
27 words
The data record carrier of claim 23 characterized in that said back track address section (44) is a mirror image of the front track address section (32).
Claim 27
Dependent Claim
70 words
The data record carrier of any one of claims 14-24 wherein two identical cyclic redundancy checksum field sections are provided, one at the beginning of each track (14) and one at the end of each track (14) and each such cyclic redundancy checksum field section is combined with a track address (32, 44) and placed in the front track address section (32) or the back track address section (44) respectively.
Claim 28
Dependent Claim
49 words
The data record carrier of claim 25 characterized in that said combined track address byte and cyclic redundancy checksum field byte are each encoded with a parity field, a cyclic redundancy checksum word is formed therefrom to form another data byte and all the resulting data bits are multiplexes.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.