Accessing data on MD

[Sparda]

How does the MD technology work? Thats a bit vague so let me rephrase. For example I have 100 tracks on my MD disc. Now when I burn my songs via SS I burn them in order (song 2 is transferred after song 1 as track 2, and so on) do they in reality physically burn one after another or is it randomly placed on the disc or are the information scattered? Lets just suppose that they burn physically one after another. So track 1 should be near the inner circle of the MD and track 100 would be at the outer edge of the MD (Follow me? Think of CD-R). Now after I've transferred the songs they should be burned in that order, but wait I pull track 100 to the very beginning, making it track 1. And now track 1 would be track 2 because I just pulled (when I say pull I mean drag over) track 100 over, then suppose I pull track 3 to the end making it track 100. Now my question to you is: does the unit re-burn the information making them physically in order, or does it just re-write the TOC and tell the MD where to look. Now imagine this situation, I play track 1 the optical head goes all the way to the outer edge of the MD disc and after track 1 is over it plays track 2 which is physically near the inner circle of the Md disc, so the optical head goes all the way back, track 3 is at the outer edge, head goes over to the opposite side, see what I'm getting at here? The optical would be going back and forth, not good, unnecessary wear and tear. Now all this would true if everything I've said is theoretically correct. Now if I'm wrong somewhere then this may not be true. But could someone explain all this to me? And tell me where I am wrong, because this is all just an educated guess. Thanks for reading this long post. Let us discuss! All comments welcome.

Edit: I think what I am talking about is whether MD is sequential access media or not?

Edited December 24, 2006 by Sparda

[fishstyc]

Only the TOC gets updated, rewriting the songs would be much more unnecessary work (and would be way too slow).

Try it out if you're not sure, you'll hear the head move. I never tried this out myself, but it's the only logical way that it can be done.

One other possiblilty would be that the file is recreated in the fat table, so that the order of the data in the file is modified, but the actual data stay on the same place on the disc. That would be easy to test, copying the ATDATA file to harddisk, make the changes and compare the ATDATA on the disc with the one on your harddisk. My guess is that this file will not have changed.