Browse Prior Art Database

Method for Specifying ECC Correction Algorithm Used for Small Computer System Interface Bus Attached CD-ROM Extended Architecture Drive

IP.com Disclosure Number: IPCOM000108634D
Original Publication Date: 1992-Jun-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 2 page(s) / 71K

Publishing Venue

IBM

Related People

Kerins, TM: AUTHOR [+2]

Abstract

This article describes a method to have a host system read the MODE field on a data track and specify to the compact disc (CD)-ROM drive what error correction code (ECC) mode to use to process the data track.

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

Method for Specifying ECC Correction Algorithm Used for Small Computer System Interface Bus Attached CD-ROM Extended Architecture Drive

       This article describes a method to have a host system
read the MODE field on a data track and specify to the compact disc
(CD)-ROM drive what error correction code (ECC) mode to use to
process the data track.

      More specifically, the method disclosed herein allows a host
system to select which ECC algorithm to use when reading CD-ROM discs
by means of an existing small computer system interface (SCSI)
command parameter.  The manual selection of the CD-ROM ECC algorithm
by the host system prevents potential errors which would occur if the
CD-ROM drive were to automatically determine the ECC algorithm by
itself.

      A CD-ROM extended architecture (XA) disc is separated into
different groups of data called data tracks, which are similar to the
tracks found in an audio CD.  These data tracks consist of one or
more data sectors of 2352 bytes in length and contain information
which is formatted according to one of two standards, the CD-ROM
standard (Mode 1 track) or the CD-ROM XA standard (Mode 2 track).
Tracks formatted to the CD-ROM standard will use a different ECC
algorithm than those formatted to the CD-ROM XA standard.

      A MODE field is included in each data sector within a data
track to indicate whether the track is in Mode 1 or Mode 2 format.
This field will contain the same value for all sectors in a
part...