Fault tolerant RLL data sector address mark decoder

Details Fault tolerant RLL data sector address mark decoder Fault tolerant RLL data sector address mark decoder

1991-06-04

1993-07-27

Pascal, Robert J.

Dynamic magnetic information storage or retrieval

General processing of a digital signal

Address coding

360 40, 341 59, G11B 509

Patent

active

052315452

ABSTRACT:
A method is provided for decoding a unique data sequence forming an address mark within a stream of RLL coded data values in order to start a byte clock for synchronizing operations within a data sequencer of a data storage system. The unique data sequence nominally comprises at least two adjacent sequences of zeros of a maximum permitted length occurring between three flux transitions under a predetermined RLL data code. This new method comprises the steps of:
detecting a first flux transition,
detecting a second flux transition,
determining the number of zeros of a first zero sequence from the first flux transition to the second flux transitions,
determining if the accumulated number of zeros of the first zero sequence is equal to the maximum permitted length, plus or minus one zero, and if so,
detecting the third flux transition,
determining the number of zeros of a second zero sequence from the second flux transition to a third flux transition,
summing the numbers of zeros of the first and second sequences,
determining if the sum is of the maximum permitted length, plus or minus one zero, and if so,
starting the byte clock in relation to the determined first and second sequences and in relation to the time of detection of the third flux transition.

REFERENCES:
patent: 4488142 (1984-12-01), Franaszek
patent: 4501000 (1985-02-01), Immink et al.
patent: 4669004 (1987-05-01), Moon et al.
patent: 4675652 (1987-06-01), Machado
patent: 4688016 (1987-08-01), Fok
patent: 4719523 (1988-01-01), Kutaragi
patent: 4752841 (1988-06-01), Syracuse et al.
patent: 4868690 (1989-09-01), Minuhin et al.
patent: 4933786 (1990-06-01), Wilson
patent: 5170299 (1992-12-01), Moon
F. Jorgensen, Handbook of Magnetic Recording 3rd Ed. .COPYRGT.1988 Tab Books, p. 683.
McCullough, Ryals, "Hard and Floppy Disks Plus Tape Obey Disk Control Chip Duo", Electronic Design, vol. 33, No. 2, Jan. 24, 1985, pp. 185-194.
Khu, Sterner, "PLDs Implement Encoder/Decoder for Disc Drive," Elect. Design News, vol. 31, No. 19, Sep. 18, 1986, pp. 285-294.
Howell, "Analysis of Correctable Errors in IBM 3380 Disk File" IBM J. Res & Develop., vol. 28, No. 2, Mar. 1984 pp. 206-211.
Matsumoto, "A 48 MB/s Disk Drive Data Separator," Proc. 1990 Bipolar Circuits & Tech. Mtg. No. 2.4, Sep. 17, 1990 Minneapolis, MN pp. 52-55.

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