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IDEDOS

1,645 bytes added, 22:12, 27 March 2011
Partition Types
There are numerous partition types [http://8bit.yarek.pl/system/fs.idedos/index.html defined]
<pre>=====Partition Type 0x00: unused partition- Unused Partition=====0x01: system This is an empty partition0x02: swap partition0x03: +3DOS partition0x04: CP/M partition0x05: boot partition0x0F: movie partition0x10: FAT16 partition0x20: UZI(X) partition0x30: TR-DOS disk image0x31: +D/SAMDOS disk image0x32: MB-02 disk image0x40: ZX Spectrum +3 disk image0x41: Elwro 800 Junior disk image0x48: Amstrad CPC disk image0x49: Amstrad PCW disk image0xFE: bad table entry. Type 0x00 entries do not describe any disk space0xFF: free disk space</pre>and should be left blank.
=====Partition Type 0x01 - The IDEDOS System Partition=====
The first partition entry in the partition table is always the IDEDOS system partition. There must only be one System Partition on a hard disk. The partition label must always be the string "PLUSIDEDOS" followed by six spaces (ascii 0x20) as this string is used to determine whether the disk was created using an 8 or 16-bit interface.
The starting head and ending head are either zero or one depending on where the partition table has been written.
The drive geometry is written in the type specific data in the bytes 0x0020 to 0x0027
??: unused
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=====Partition Type 0x02 - Swap Space=====
Swap partitions can be created with the [[+3e|+3e ROMs]] however no software is known to use them.
=====Partition Type 0x03 - +3DOS=====
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 =====Partition Type 0x04 - CP/M Partition=====[[CP/M]] partition with an XDPB which reflects the geometry of the physical disk. The partition must use a whole number of cylinders and use whole number of tracks. If the partition does not start at track 0 of the cylinder the area before the partition on that cylinder must be marked as reserved tracks in the XDPB. =====Partition Type 0x05 - Boot Partition=====A partition of type 0x05 is accessed as a single file. This can be used as a boot file for example a [[Timex FDD3000]] with a [[YABUS.TF]] searches for a type 0x05 partition with the label "YABUS.TF". If found the contents of the partition are copied to RAM and executed. =====Partition Type 0x0F - Movie Partition=====Partition containing a sequence of screenshots (and sound). =====Partition Type 0x10 - FAT-16 Partition=====Partition containing a FAT-16 filesystem. =====Partition Type 0x20 - UZI(X) Partition=====Partition for UZI(X) the UNIX Implementation for MSX. =====Partition Types 0x3x - Non-CP/M Disk Image Partitions=====
For partitions containing non-CP/M floppy disk images the type specific information defines a virtual geometry. More than one disk image partition can be present on each track, i.e. the partitions do not have to align to track boundaries.
This is achieved by specifying a sector shift in the partition table entry. For example for a disk with 980 cylinders, 5 heads, 17 sectors per track and 512 bytes per sector, a 800kB partition takes 1600 sectors which is equal to 18 cylinders + 4 tracks + 2 sectors, so the shift for next partition is 2.
The following non-CP/M format disk image types are defined:* 0x30: [[TR-DOS]] image.* 0x31: [[+D]]/SAMDOS image.* 0x32: [[MB-02]] image.* 0x33: [[Timex FDD3000#TOS A.2|TOS A.2]] image.  =====Partition Types 0x4x - CP/M Disk Image Partitions=====The following CP/M format disk image types are defined:* 0x40: [[ZX Spectrum +3/2A/2B|ZX Spectrum +3]] image.* 0x41: Elwro 800 Junior image.* 0x48: Amstrad CPC image.* 0x49: Amstrad PCW image.  =====Partition Type 0xFE - Bad Disk Space=====Drive space which should not be used. =====Partition Type 0xFF - Free Disk Space=====
A Type 0xFF partition entry as created by the +3e ROMs is all blank except for the type byte and the location and size information. The type specific information is not used.

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