Re: [MiNT] (fwd) Revisited: HDDRIVER, FAT32, MiNT, FAT too small

[Frank Naumann <fnaumann@boerde.de>]

Hello Jo Even!

> When creating a FAT32 partition of 4095 MB HDDRUTIL allocates 8386528
> sectors of 512 bytes for the FATs and the actual data area. 8174 sectors
> are allocated for each FAT, which means that 8386528-2*8174=8370180
> sectors remain for the actual data. There are 8 sectors per cluster,
> which means that there are 8386528/8=1046272 data clusters. For each of
> these 1046272 clusters a 32 bit FAT entry is required, which means that
> 1046272*4=4185088 bytes are needed per FAT. This is exactly what 8174
> sectors per FAT amount to: 8174*512=4185088.
>
> This calculation shows that the number of FAT sectors allocated by
> HDDRUTIL is exactly the number of sectors needed.
> If my calculation is right MiNT is wrong and should be fixed. If my
> calculation is wrong please point out the error so that I can fix my code.

What about the two empty (unused) entries at the start of each FAT table?


Regards,
Frank

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ATARI FALCON 060 // MILAN 060
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