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Re: Reference for layout of ProDOS and DOS 3.3. sector ordering?

schmidtd wrote:

Andy McFadden wrote:


The way I addressed this in CiderPress was to convert from the file's
ordering to "physical" and then "physical" to the requested sector in
the current mode.  If you can convert ProDOS blocks to physical sector
numbers, and DOS sector numbers to physical sector numbers, then you can
convert between ProDOS blocks and DOS sectors with two calculations.



I think, for my purposes, I could make do with a server-side (in the
ADT sense) converter from .po to .do and back again.  (I would then
always assume .po at the Apple end.)  Would NufxLib be my solution to
do the conversion?  Not that rearranging sectors would be all that
hard, but if there were a ready-made solution...


Rearranging sectors is, in fact, a trivial transformation.

All you need is a 16-entry table to index to the offset of the next
256 bytes to send!  That's a 16-entry table and one line of code
inside the sector loop.

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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