Browse Prior Art Database

Method for Transmitting CD-ROM Error Syndromes Across the Small Computer System Interface Bus

IP.com Disclosure Number: IPCOM000108594D
Original Publication Date: 1992-Jun-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 2 page(s) / 76K

Publishing Venue

IBM

Related People

Kerins, TM: AUTHOR [+2]

Abstract

This article describes a method for sending compact disc (CD)-ROM error information to a host system so that error compensation on CD-ROM extended architecture (XA) data sectors may be performed by the host.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Method for Transmitting CD-ROM Error Syndromes Across the Small Computer System Interface Bus

       This article describes a method for sending compact disc
(CD)-ROM error information to a host system so that error
compensation on CD-ROM extended architecture (XA) data sectors may be
performed by the host.

      In the CD-ROM XA standard, CD-ROM data sectors can be one of
two formats, Form 1 or Form 2.  In the Form 1 format, which is used
for executable programs and other critical data, error correction
code (ECC) information is included in the data sectors which allows
the CD-ROM drive to correct for data errors which may occur while
reading the CD-ROM XA disc.  This ECC information (along with the
base ECC information which is present in all CDs whether CD-digital
audio (DA) or CD-ROM) allows the CD-ROM drive to achieve a 10** -12
error rate while reading Form 1 data, which matches the error rate on
standard magnetic disk drives.

      In the Form 2 format, which is used for digital video and audio
data, ECC information is not included in the data sectors.  Because
of this, the CD-ROM drive has only the CD-DA base ECC data available
for correcting errors which allows the CD-ROM drive to achieve a 10**
-9 error rate. This base ECC data provides enough information to do
error detection down to a byte level within the CD-ROM Form 2 data,
but not enough information to do full error correction on the data.

      The method described herein provides a means of passing CD-DA
error detection information to the host computer across the small
computer system interface (SCSI) bus.  This allows the host system to
attempt to do error compensation...