CD-ROM XA

CD-ROM XA is an extension of the Yellow Book standard for CD-ROMs that combines compressed audio, video and computer data, allowing all to be accessed simultaneously. It was intended as a bridge between CD-ROM and CD-i (Green Book) and was developed by Sony and Philips. "XA" stands for eXtended Architecture.

CD-ROM sector types:

1. Audio (2352):
   Data (2352)
   Raw data, no ECC; used for audio.
2. Mode 1 (2048):
   Sync (12), Address (3), Mode (1), Data (2048), EDC (4), reserved (8), ECC (276)
   2048 bytes of user data with error correction; usually used for computer data.
3. Mode 2 (2336):
   Sync (12), Address (3), Mode (1), Data (2336)
   2336 bytes of user data, no ECC; usually used for compressed audio, video or picture.

CD-ROM XA defines two forms of Mode 2 sectors:

1. Mode 2 Form 1 (2048):
   Sync (12), Address (3), Mode (1), Subheader (8), Data (2048), EDC (4), ECC (276)
   2048 bytes of user data, ECC, can interleave with Mode 2 Form 2 sectors, used for data.
2. Mode 2 Form 2 (2324):
   Sync (12), Address (3), Mode (1), Subheader (8), Data (2324), EDC (4)
   2324 bytes of user data, error detection, can interleave with Mode 2 Form 1 sectors; used for audio/video data.

Bibliography

• McFadden, Andy (2002-12-20). "What is XA? CDPLUS? CD-i? MODE1 vs MODE2? Red/yellow/blue book?". CD-Recordable FAQ. Retrieved 2008-05-04.
• Sony Storage Support - What are CD-ROM Mode-1, Mode-2 and XA?