henkp@nikhefk.uucp (Henk Peek) (10/21/86)
CD-ROM readers are expensive (or not ?). With a low-cost audio compact-disk player and some additional hardware, it can be done much cheaper. Questions: -Is the CD-ROM error-correction and data-format identical to the (audio) compact-disk. -Are there procedings of the first CD-ROM conference 1986? -Are there other usefull references? I will summarize direct replays to net.periphs Uucp: henkp@nikhefk.UUCP ..!seismo!mcvax!nikhefk!henkp Mail: Henk Peek, NIKHEF-K, PB 4395, 1009 AJ Amsterdam, Holland
drg@briar.UUCP (Don Gentner) (10/30/86)
In article <41@nikhefk.UUCP>, henkp@nikhefk.uucp (Henk Peek) writes: > -Is the CD-ROM error-correction and data-format identical > to the (audio) compact-disk. > -Are there procedings of the first CD-ROM conference 1986? > -Are there other usefull references? The CD-ROM format is built on top of the CD-Audio format. The basic data unit in CD-Audio is the frame (24 bytes of audio data). In CD-ROM, the basic unit is the block, made up of 98 frames for a total of 2352 bytes of data per block. There are two CD-ROM formats. In Mode 1, a block contains 16 bytes of header, 2048 bytes of user data, and 288 bytes of error detection and correction codes. These 288 bytes of ED/EC are in addition to the normal error detection and correction codes in CD-Audio, giving Mode 1 CD-ROM a nominal error rate of 1 error per 200 million discs!!! In Mode 2, a block contain 16 bytes of header and 2336 bytes of user 18 data. Mode 1 is normally used for text and data; Mode 2 is used for graphics and sound, where a few errors don't hurt so much. I don't believe there are procedings of the CD-ROM conference. There's some discussion of CD-ROM format in Byte, May 1986, pp 164-165. Don Gentner Philips Laboratories Briarcliff Manor, NY 10510 gentner@nprdc.arpa {seismo,decvax,ihnp4}!philabs!gentner