A CDDA has 2352 bytes of main data and 96 byte of sub-channel data per sector, so a total of 2448 bytes per sector. A sector is made up of 98 sub-frames. Each s

A CDDA has 2352 bytes of main data and 96 byte of sub-channel data per sector, so a total of 2448 bytes per sector. A sector is made up of 98 sub-frames. Each such sub-frame has 24 bytes of main data, 4 bytes of C1 error correction and 4 bytes of C2 error correction, and 1 "byte" of sub-channel data. The first 2 sub-frames have a special pattern in the sub channel data to recognize the start of the sector, leaving 96 bytes of sub-channel data available for other things. The error correction only covers the main data, the sub channel data just has a CRC. The standard API to talk to the CD-ROM does not have a way to get the C1 and C2 error correction data. There is only a way to get 1 bit for each of the 2352 main data bytes after the C2 error correction to indicate that there was an error with it or not. But getting that data doesn't actually seem to be useful on the drives I tested it with, they all seem to have weird firmwares.