DOS3 File System

Boot sector

Sectors $01-$09 is boot sector.
$0A-$0F are empty.

Directory

$10-$17 are directory. I don't know what's first entry, containing $0E empty bytes and $7F $A5 at the end (for MD) and $57 $A5 for SD.

Offset Description
$00 Flags
bit 0 Unknown
bit 1 Unknown
bit 2 Unknown
bit 3 Unknown
bit 4 Unknown
bit 5 Unknown
bit 6 Unknown
bit 7 Unknown
$01-$08 Filename (padded by spaces)
$09-$0B Extension (padded by spaces)
$0C Number of blocks (8 sectors)
$0D Starting block
$0E-$0F Length of file in bytes

FAT

Sector $18 is FAT. Maximum number of blocks that could be allocated is $7F.
  • $FF - can't be allocated
  • $FE - free
  • $FD - eof
  • other - link to other block

This format is just guessed. . Back (c) 1998-2004 Jindroush Last modified: Sun Dec 5 19:28:22 1999