First post, by superfury
I know that the CD-ROM(ATAPI using sff8020i) reads use either LBA or MSF addressing. One thing I don't understand is the physical disk(in this case an iso file or cue-sheet) and it's effect on that addressing(the tracks and absolute disk addresses including pregap, postgap, audio and mode 1/2 data.
How is the LBA/MSF converted to the absolute (cue-based) address?
- What happens during the read (10/12) commands? How does pregap, postgap, track type affect this(besides only allowing mode 1/2 tracks)? How is the LBA address converted to the physical MSF address of the sector? How does pregap/postgap affect this? Does pregap add to the LBA/MSF address(move it after the pregap, essentially adding the pregap/INDEX 00 entry for the sector address)?
- What happens during the audio commands with pregap/postgap? Does it play those as zeroed blocks of audio?
- How do the track numbers affect all of it? Are they in effect at all during reads or playback(other than reporting them to software through the read TOC command)?
So, for example, what happens with a data track with pre and/or postgap?
And what happens during reading (by software) the pregap/postgap areas of an audio track?
Also, there's one command I can't quite identify the purpose of: the SEEK command. Is that purely for audio playback? Afaik it won't affect data track reads, as they are either locked to track 1 only or being seeked accross all tracks? Or does tracks say nothing except when reporting them in the TOC?
What happens with data tracks not at track 01? Or multiple data tracks? Or multiple data tracks with audio tracks(1 or more) between them?
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