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Re: Volume Number support for .dsk images



Rubywand wrote:
>Like emu writers don't have enough to do, here's another wish list item: Why not add support for Volume Numbering of .dsk images?

And don't forget as was pointed out earlier, it is embedded in the VTOC on track 11, sector 0, Byte 6 on DOS 3.3 diskettes... No file name convention required. (ProDOS is always the same volume number, 1, I think.)

Look for pattern "04 xx xx 03 xx xx ##", ignore the xx bytes and use the ## number for the volume when reporting to DOS.

Thankx,
Ed

Extra info taken form the FAQ about the VTOC on a DOS 3.3 diskette...

Track 11, Sector 0:
Byte   Meaning
----   -------
$00    Unused (always $04 on my disks)
$01-02 Track/Sector location of first catalog sector-- the standard
       location is Track $11/Sector $0F (17/15)
       Note: The location of first catalog sector may be different on some
       disks. DOS 3.3 can adjust; but, some utilities (e.g. Copy II Plus)
       assume T/S $11/$0F and will not be able to find the catalog.
$03    DOS version number ($03 for DOS 3.3)
$04-05 Unused
$06    Volume Number-- $01-$FE (1-254) is the standard range;
       $FE (254) is the standard default VN
       Note: This entry merely records the VN for handy reference.
       VN is set when a disk is INITed and it is embedded in the
       Address header of each sector.
$07-26 Unused