Specifications

MICROPROCESSADORES
INTERRUPÇÕES
5
Luís Miguel Charrua Figueiredo 5 - 19 E.N.I.D.H.
how much extended memory has been used by VDISKs (see #00649). DOS 3.3+
PRINT hooks INT 19 but does not set up a correct VDISK header block at the
beginning of its INT 19 handler segment, thus causing some programs to
overwrite extended memory which is already in use. the default handler is at
F000h:E6F2h for 100% compatible BIOSes MS-DOS 3.2+ hangs on booting (even
from floppy) if the hard disk contains extended partitions which point at each other
in a loop, since it will never find the end of the linked list of extended partitions
under Windows Real and Enhanced modes, calling INT 19 will hang the system in
the same was as under bare DOS; under Windows Standard mode, INT 19 will
successfully perform a cold reboot as it appears to have been redirected to a MOV
AL,0FEh/OUT 64h,AL sequence
BUG
: when loading the remainder of the DOS system files fails, various
versions of IBMBIO.COM/IO.SYS incorrectly restore INT 1E before calling INT 19,
assuming that the boot sector had stored the contents of INT 1E at DS:SI instead
of on the stack as it actually does
SeeAlso
: INT 14/AH=17h,INT 18"BOOT HOOK",INT 49"Tandy 2000",INT 5B"PC
Cluster"
SeeAlso
: MEM 0040h:0067h,MEM F000h:FFF0h,CMOS 0Fh
Format of VDISK header block (at beginning of INT 19 handler's segment):
Offset Size Description (Table 00649)
00h 18 BYTEs n/a (for VDISK.SYS, the device driver header)
12h 11 BYTEs signature string "VDISK Vn.m" for VDISK.SYS version
n.m
1Dh 15 BYTEs n/a
2Ch 3 BYTEs linear address of first byte of available extended memory
Format of hard disk master boot sector:
Offset Size Description (Table 00650)
00h 446 BYTEs Master bootstrap loader code
1BEh 16 BYTEs partition record for partition 1 (see #00651)
1CEh 16 BYTEs partition record for partition 2
1DEh 16 BYTEs partition record for partition 3
1EEh 16 BYTEs partition record for partition 4
1FEh WORD signature, AA55h indicates valid boot block
Format of partition record:
Offset Size Description (Table 00651)
00h BYTE boot indicator (80h = active partition)
01h BYTE partition start head
02h BYTE partition start sector (bits 0-5)
03h BYTE partition start track (bits 8,9 in bits 6,7 of sector)
04h BYTE operating system indicator (see #00652)
05h BYTE partition end head
06h BYTE partition end sector (bits 0-5)
07h BYTE partition end track (bits 8,9 in bits 6,7 of sector)
08h DWORD sectors preceding partition
0Ch DWORD length of partition in sectors
SeeAlso
: #00650
(Table 00652)
Values for operating system indicator:
00h empty partition-table entry
01h DOS 12-bit FAT
02h XENIX root file system
03h XENIX /usr file system (obsolete)
04h DOS 16-bit FAT (up to 32M)
05h DOS 3.3+ extended partition
06h DOS 3.31+ Large File System (16-bit FAT, over 32M)
07h QNX
07h OS/2 HPFS
07h Windows NT NTFS
07h Advanced Unix
07h see partition boot record; could be any of the above or others
08h OS/2 (v1.0-1.3 only)
08h AIX bootable partition, SplitDrive
08h Commodore DOS
08h DELL partition spanning multiple drives
09h AIX data partition
09h Coherent filesystem
0Ah OS/2 Boot Manager
0Ah OPUS
0Ah Coherent swap partition
0Bh Windows95 with 32-bit FAT
0Ch Windows95 with 32-bit FAT (using LBA-mode INT 13 extensions)
0Eh logical-block-addressable VFAT (same as 06h but using LBA-mode
INT 13)
0Fh logical-block-addressable VFAT (same as 05h but using LBA-mode
INT 13)
10h OPUS
11h OS/2 Boot Manager hidden 12-bit FAT partition
12h Compaq Diagnostics partition
14h (resulted from using Novell DOS 7.0 FDISK to delete Linux Native
part)
14h OS/2 Boot Manager hidden sub-32M 16-bit FAT partition
16h OS/2 Boot Manager hidden over-32M 16-bit FAT partition
17h OS/2 Boot Manager hidden HPFS partition
17h hidden NTFS partition
18h AST special Windows swap file ("Zero-Volt Suspend" partition)
19h Willowtech Photon coS
1Bh hidden Windows95 FAT32 partition
1Ch hidden Windows95 FAT32 partition (using LBA-mode INT 13
extensions)
1Eh hidden LBA VFAT partition
20h Willowsoft Overture File System (OFS1)
21h officially listed as reserved
21h FSo2
23h officially listed as reserved
24h NEC MS-DOS 3.x
26h officially listed as reserved
31h officially listed as reserved
33h officially listed as reserved
34h officially listed as reserved
36h officially listed as reserved
38h Theos
3Ch PowerQuest PartitionMagic recovery partition
40h VENIX 80286
41h Personal RISC Boot
41h PowerPC boot partition
42h SFS (Secure File System) by Peter Gutmann
45h EUMEL/Elan
46h EUMEL/Elan
47h EUMEL/Elan
48h EUMEL/Elan
4Fh Oberon boot/data partition
50h OnTrack Disk Manager, read-only partition
51h OnTrack Disk Manager, read/write partition
51h NOVELL
52h CP/M
52h Microport System V/386
53h OnTrack Disk Manager, write-only partition???
54h OnTrack Disk Manager (DDO)
55h EZ-Drive (see also INT 13/AH=FFh"EZ-Drive")
56h GoldenBow VFeature
5Ch Priam EDISK
61h SpeedStor
63h Unix SysV/386, 386/ix
63h Mach, MtXinu BSD 4.3 on Mach
63h GNU HURD
64h Novell NetWare 286
64h SpeedStore
65h Novell NetWare (3.11)
67h Novell
68h Novell
69h Novell
70h DiskSecure Multi-Boot
71h officially listed as reserved
73h officially listed as reserved
74h officially listed as reserved
75h PC/IX