Today, with the help of Truong Hi, the coder of PerfectRip, we've come up with a better way of detecting the combined read+write offset of a disc. This new method expands upon our previous discovery, and also proves that our current methods of correcting both offsets are correct.
The principle is that, by using the D8 vendor read command on compatible drives, data sectors are read in audio mode and thus become scrambled. The sync remains unscrambled, and its position can be used to determine the combined read+write offset.
Advantages over old method:
- Works on all discs with data tracks
- All data track sectors can be used to detect
Disadvantage:
- It requires a drive that supports the D8 read command. Most Plextor drives (original ones, not rebadged) are confirmed to support this command (755A, 760A, etc).
Software needed:
Px_D8 v1.01A by Truong Hi and Dremora - http://soft.dremora.com/px_d8_1.01A.7z
Usage: px_d8 <drive letter> <LBA sector>
For LBA sector you can just put '0' or any number. If your drive supports the command, it will give you the Combined offset (the offset that is used in EAC for dumping audio tracks).
Precautions:
- If you have a Plextor drive, be sure to update to the latest firmware available for your drive!