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Structure of .ST files

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Paolo

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Apr 21, 2012, 7:37:27 AM4/21/12
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Please, what is the structure of a .ST file emulating an Atari ST
floppy disk?
It gets 738.260 B versus 726.016 on the FD.
Thanks
Paul

Guillaume Tello

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Apr 21, 2012, 9:39:27 AM4/21/12
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A standard floopy has:
80 tracks with 9 sectors of 512 bytes on each side, so it is a total of:
80*9*2*512 = 737 280 bytes.

Some sectors are reserved for boot + FAT, so you only get 726 016 bytes
available for storage.

738260 - 737280 = 980 bytes added.
Well, I can't say more in this organisation of those 980 bytes.

Guillaume.

Peter Dassow

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Apr 24, 2012, 5:13:33 PM4/24/12
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It's similar to MS-DOS formatted floppy disks.
You have a boot sector (512 Bytes), which is always not usable for data.
And you have some File Allocation Table sectors, and last but not least
a few sectors for directory entries.
How many sectors are used for FAT and Directory Entries is set by some
bytes/numbers in the mentioned boot sector.

So this is no rocket science.

Charles Richmond

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Apr 25, 2012, 7:26:19 PM4/25/12
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"Peter Dassow" <z8...@arcor.de> wrote in message
news:4f971782$0$6555$9b4e...@newsspool4.arcor-online.net...
I believe that there are *two* copies of the FAT table, in case one becomes
corrupted.

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