发明名称 Disk data reproducing apparatus and disk data reproducing method
摘要 A disk data reproducing apparatus and a disk data reproducing method for carrying out error correction at fixed intervals independent of demodulation rate fluctuations caused by variable disk revolutions during access, whereby the reliability of error correction is improved. Data are demodulated by use of a regenerative clock signal acquired in keeping with the input data rate, whereas error correction is conducted at a fixed frequency clock signal. Two counters are provided, one being incremented by a signal generated upon detection of a block top, the other counter being incremented by a signal generated when a block of erroneous data is corrected. The two computers are compared in contents so that depending on the result of the comparison, an error correction start signal is generated. Error correction is performed always at fixed intervals regardless of the velocity of reproduction being standard, doubled, quadrupled, or multiplied by a factor of j (j: natural number). Error correction, performed on the fixed frequency clock signal, takes shorter than data demodulation through reproduction at a maximum linear velocity. Thus even if data cannot be read, error correction proceeds irrespective of the demodulation anomalies so that error correction is performed reliably.
申请公布号 US6092232(A) 申请公布日期 2000.07.18
申请号 US19980042659 申请日期 1998.03.17
申请人 HITACHI, LTD. 发明人 NAGAI, YUTAKA;KUDO, TOMOAKI;HIRABAYASHI, MASAYUKI;TAKEUCHI, TOSHIFUMI;GUNJI, HIROYUKI
分类号 G11B19/28;G11B19/247;G11B20/10;G11B20/18;G11B27/36;G11C29/00;(IPC1-7):G11C29/00 主分类号 G11B19/28
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