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Re: The Virtual Partition - say goodbye to FAT12

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"wolfgang kern" wrote:
> "Mike Gonta" wrote:
>> "wolfgang kern" wrote:

> Hello Mike,
>>> What's wrong by using FAT16 instead of FAT12 for small
>>> systems ?
>
>> Hi wolfgang,
>
>> What's "wrong" with using FAT12 for small systems?
>
> Me too see FAT12 as a weird historical requirement, I
meant that FAT16 could replace FAT12 with lesser overhead.

And now FAT32 can replace both.

>> The Virtual Partition enables the use of the exact same
>> simple FAT12 driver for an unmodified fully compliant
>> FAT32 volume. What's wrong with that?
>
> Yeah, you haven't said it before.
> So most of us are still in doubt what your
> FAT32-modifaction was all about...
> Meanwhile a few of us older AOD's may have got your idea :)

Maybe, but I'm not quite sure.

>> The only difference in the driver is that the FAT table
>> entries are 32 bit instead of 12 bit. As a bonus, the 32 bit
>> entries are easier to handle than the odd sized (not a
>> native CPU word size) 12 bit which can also cross a sector
>> boundary for added complications. Of course, a full blown
>> FAT32 driver is expected to process the entries as the
>> actual 28 bit that it is and maintain the top 4 (reserved)
>> bits. It's way past the need to be concerned about the
>> mature FAT32 file system anymore (and even if the bits are
>> used - say by a file utility) the hobbyist system can safely
>> ignore them. Of course, handling them correctly is only a
>> minor thing anyway. Some other small nit picks that would
>> make the drivers different such as having the directory
>> entry for the file start cluster in two parts in two
>> different places is also easily ignored (and just as easily
>> handled) since the size of the Virtual Partition - even when
>> 8MB would have a max cluster number of only 16K which easily
>> fits in the original 16 bit entry anyway.
>
> After all, you could have just said that you only made the
> FAT-32 root directory a fix-size like old FAT12/16 instead
> of dynamic.

Basically that and the "fence file" is essentially what the
AOD Virtual Partition is all about. Keep in mind that I
didn't "make" it, it's merely "formatted" that way and still
fully dynamic. The pre-allocation merely makes those clusters
contiguous so the users of the AOD Virtual Partition can
merely load a "fixed" size contiguous table, existing
software still happily follows the cluster chain to do so.

> so why that many posts and distracting words for a single
> matter :)

Yes, I know, I talk too much.


Mike Gonta
look and see - many look but few see

http://mikegonta.com
http://tawk.to/mikegonta 

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The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-03-31 17:51 -0400
  Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-03-31 20:48 -0500
    Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-01 06:50 -0400
      Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-01 11:06 -0500
        Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-01 13:45 -0400
          Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-01 17:06 -0500
            Re: The Virtual Partition - say goodbye to FAT12 James Harris <james.harris.1@gmail.com> - 2016-04-01 23:16 +0100
              Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-01 17:29 -0500
                Re: The Virtual Partition - say goodbye to FAT12 Rod Pemberton <NoHaveNotOne@bcczxcfre.cmm> - 2016-04-01 20:24 -0400
                Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-02 00:10 -0500
                Re: The Virtual Partition - say goodbye to FAT12 Rod Pemberton <NoHaveNotOne@bcczxcfre.cmm> - 2016-04-02 12:03 -0400
                Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 20:19 -0400
                Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 20:08 -0400
                Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 20:02 -0400
                Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 19:55 -0400
              Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 19:30 -0400
            Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 18:55 -0400
              Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-04 00:40 -0500
  Re: The Virtual Partition - say goodbye to FAT12 "wolfgang kern" <nowhere@never.at> - 2016-04-01 09:20 +0200
    Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-01 07:01 -0400
      Re: The Virtual Partition - say goodbye to FAT12 "wolfgang kern" <nowhere@never.at> - 2016-04-04 10:42 +0200
        Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-05 15:58 -0400
          Re: The Virtual Partition - say goodbye to FAT12 "wolfgang kern" <nowhere@never.at> - 2016-04-05 22:19 +0200
            Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-05 18:24 -0400
  Re: The Virtual Partition - say goodbye to FAT12 James Harris <james.harris.1@gmail.com> - 2016-04-01 09:55 +0100
    Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-01 07:11 -0400
  Re: The Virtual Partition - say goodbye to FAT12 Rod Pemberton <NoHaveNotOne@bcczxcfre.cmm> - 2016-04-01 20:24 -0400
    Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 21:30 -0400

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