2001-06-20 20:31:35 +00:00
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;
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; Win2k FAT32 Boot Sector
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;
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; Brian Palmer <brianp@sginet.com>
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;
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;
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; The BP register is initialized to 0x7c00, the start of
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; the boot sector. The SP register is initialized to
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; 0x7bf4, leaving 12 bytes of data storage space above
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; the stack.
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;
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; The DWORD that gets stored at 0x7bf4 is 0xffffffff ??
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;
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; The DWORD that gets stored at 0x7bf8 is the count of
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; total sectors of the volume, calculated from the BPB.
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;
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; The DWORD that gets stored at 0x7bfc is the logical
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; sector number of the start of the data area.
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;
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2002-04-16 06:11:08 +00:00
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org 7c00h
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2001-05-15 03:50:25 +00:00
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segment .text
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bits 16
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start:
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jmp short main
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nop
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2001-07-06 22:05:05 +00:00
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OEMName db 'MSWIN4.0'
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2001-05-15 03:50:25 +00:00
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BytesPerSector dw 512
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SectsPerCluster db 1
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ReservedSectors dw 1
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NumberOfFats db 2
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MaxRootEntries dw 0 ;512 - Always zero for FAT32 volumes
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TotalSectors dw 0 ;2880 - Always zero for FAT32 volumes
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MediaDescriptor db 0f8h
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SectorsPerFat dw 0 ;9 - Always zero for FAT32 volumes
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SectorsPerTrack dw 18
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NumberOfHeads dw 2
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HiddenSectors dd 0
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TotalSectorsBig dd 0
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; FAT32 Inserted Info
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SectorsPerFatBig dd 0
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ExtendedFlags dw 0
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FSVersion dw 0
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RootDirStartCluster dd 0
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FSInfoSector dw 0
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BackupBootSector dw 6
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Reserved1 times 12 db 0
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; End FAT32 Inserted Info
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2002-04-16 06:11:08 +00:00
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BootDrive db 80h
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2001-05-15 03:50:25 +00:00
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Reserved db 0
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ExtendSig db 29h
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SerialNumber dd 00000000h
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2001-07-06 22:05:05 +00:00
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VolumeLabel db 'NO NAME '
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FileSystem db 'FAT32 '
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2001-05-15 03:50:25 +00:00
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main:
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00007C5A 33C9 xor cx,cx
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2001-06-20 20:31:35 +00:00
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00007C5C 8ED1 mov ss,cx ; Setup the stack
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00007C5E BCF47B mov sp,0x7bf4 ; Give us 12 bytes of space above the stack
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2001-05-15 03:50:25 +00:00
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00007C61 8EC1 mov es,cx
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00007C63 8ED9 mov ds,cx
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00007C65 BD007C mov bp,0x7c00
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2001-06-20 20:31:35 +00:00
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00007C68 884E02 mov [bp+0x2],cl ; Zero out the nop instruction?? (3rd byte of the boot sector)
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2001-05-15 03:50:25 +00:00
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00007C6B 8A5640 mov dl,[bp+BootDrive]
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00007C6E B408 mov ah,0x8
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00007C70 CD13 int 0x13 ; Int 13, func 8 - Get Drive Parameters
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2001-06-20 20:31:35 +00:00
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00007C72 7305 jnc drive_param_ok ; If no error jmp
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drive_param_error:
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00007C74 B9FFFF mov cx,0xffff ; We couldn't determine the drive parameters
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00007C77 8AF1 mov dh,cl ; So just set the CHS to 0xff
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drive_param_ok:
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00007C79 660FB6C6 movzx eax,dh ; Store the number of heads in eax
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00007C7D 40 inc ax ; Make it one-based because the bios returns it zero-based
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00007C7E 660FB6D1 movzx edx,cl ; Store the sectors per track in edx
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00007C82 80E23F and dl,0x3f ; Mask off the cylinder bits
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00007C85 F7E2 mul dx ; Multiply the sectors per track with the heads, result in dx:ax
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00007C87 86CD xchg cl,ch ; Switch the cylinder with the sectors
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00007C89 C0ED06 shr ch,0x6 ; Move the top two cylinder bits down where they should be
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00007C8C 41 inc cx ; Make it one-based because the bios returns it zero-based
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2001-05-15 03:50:25 +00:00
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00007C8D 660FB7C9 movzx ecx,cx
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2001-06-20 20:31:35 +00:00
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00007C91 66F7E1 mul ecx ; Multiply the cylinders with (heads * sectors) [stored in dx:ax already]
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00007C94 668946F8 mov [bp-0x8],eax ; This value is the number of total sectors on the disk, so save it for later
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00007C98 837E1600 cmp word [bp+TotalSectors],byte +0x0 ; Check the old 16-bit value of TotalSectors
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00007C9C 7538 jnz print_ntldr_error_message ; If it is non-zero then exit with an error
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2001-05-15 03:50:25 +00:00
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2001-06-20 20:31:35 +00:00
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00007C9E 837E2A00 cmp word [bp+FSVersion],byte +0x0 ; Check the file system version word
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00007CA2 7732 ja print_ntldr_error_message ; If it is not zero then exit with an error
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2001-05-15 03:50:25 +00:00
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2001-06-20 20:31:35 +00:00
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;
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; We are now ready to load our second sector of boot code
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; But first, a bit of undocumented information about how
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; Win2k stores it's second sector of boot code.
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;
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; The FAT32 filesystem was designed so that you can store
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; multiple sectors of boot code. The boot sector of a FAT32
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; volume is actually three sectors long. Microsoft extended
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; the BPB so much that you can't fit enough code in the
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; boot sector to make it work. So they extended it. Sector 0
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; is the traditional boot sector, sector 1 is the FSInfo sector,
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; and sector 2 is used to store extra boot code to make up
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; for the lost space the BPB takes.
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;
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; Now this creates an interesting problem. Suppose for example
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; that the user has Win98 and Win2k installed. The Win2k
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; boot sector is stored at sector 0 and the Win98 boot sector is
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; stored as BOOTSECT.DOS on the file system. Now if Win2k were
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; to store it's second sector of boot code in sector 2 like
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; the fat spec says to do then when you try to dual boot back
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; to Win98 the Win98 boot sector will load Win2k's second
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; sector of boot code. Understand? ;-)
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;
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; To get around this problem Win2k stores it's second sector
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; of boot code elsewhere. This sector is always stored at sector 13
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; on the file system. Now don't ask me what happens when you don't
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; have enough reserved sectors to store it, but I've never seen a
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; FAT32 volume that didn't have at least 32 reserved sectors.
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;
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00007CA4 668B461C mov eax,[bp+HiddenSectors] ; Get the count of hidden sectors
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00007CA8 6683C00C add eax,byte +0xc ; Add 12 to that value so that we are loading the 13th sector of the volume
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00007CAC BB0080 mov bx,0x8000 ; Read the sector to address 0x8000
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00007CAF B90100 mov cx,0x1 ; Read just one sector
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00007CB2 E82B00 call read_sectors ; Read it
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00007CB5 E94803 jmp 0x8000 ; Jump to the next sector of boot code
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2001-05-15 03:50:25 +00:00
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print_disk_error_message:
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00007CB8 A0FA7D mov al,[DISK_ERR_offset_from_0x7d00]
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putchars:
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00007CBB B47D mov ah,0x7d
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00007CBD 8BF0 mov si,ax
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get_another_char:
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00007CBF AC lodsb
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00007CC0 84C0 test al,al
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00007CC2 7417 jz reboot
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00007CC4 3CFF cmp al,0xff
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00007CC6 7409 jz print_reboot_message
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00007CC8 B40E mov ah,0xe
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00007CCA BB0700 mov bx,0x7
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00007CCD CD10 int 0x10
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00007CCF EBEE jmp short get_another_char
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print_reboot_message:
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00007CD1 A0FB7D mov al,[RESTART_ERR_offset_from_0x7d00]
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00007CD4 EBE5 jmp short putchars
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print_ntldr_error_message:
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00007CD6 A0F97D mov al,[NTLDR_ERR_offset_from_0x7d00]
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00007CD9 EBE0 jmp short putchars
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reboot:
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00007CDB 98 cbw
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00007CDC CD16 int 0x16
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00007CDE CD19 int 0x19
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read_sectors:
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00007CE0 6660 pushad
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00007CE2 663B46F8 cmp eax,[bp-0x8]
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00007CE6 0F824A00 jc near 0x7d34
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00007CEA 666A00 o32 push byte +0x0
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00007CED 6650 push eax
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00007CEF 06 push es
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00007CF0 53 push bx
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00007CF1 666810000100 push dword 0x10010
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00007CF7 807E0200 cmp byte [bp+0x2],0x0
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00007CFB 0F852000 jnz near 0x7d1f
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00007CFF B441 mov ah,0x41
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00007D01 BBAA55 mov bx,0x55aa
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00007D04 8A5640 mov dl,[bp+BootDrive]
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00007D07 CD13 int 0x13
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00007D09 0F821C00 jc near 0x7d29
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00007D0D 81FB55AA cmp bx,0xaa55
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00007D11 0F851400 jnz near 0x7d29
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00007D15 F6C101 test cl,0x1
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00007D18 0F840D00 jz near 0x7d29
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00007D1C FE4602 inc byte [bp+0x2]
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00007D1F B442 mov ah,0x42
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00007D21 8A5640 mov dl,[bp+BootDrive]
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00007D24 8BF4 mov si,sp
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00007D26 CD13 int 0x13
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00007D28 B0F9 mov al,0xf9
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00007D2A 6658 pop eax
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00007D2C 6658 pop eax
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00007D2E 6658 pop eax
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00007D30 6658 pop eax
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00007D32 EB2A jmp short 0x7d5e
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00007D34 6633D2 xor edx,edx
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00007D37 660FB74E18 movzx ecx,word [bp+SectorsPerTrack]
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00007D3C 66F7F1 div ecx
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00007D3F FEC2 inc dl
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00007D41 8ACA mov cl,dl
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00007D43 668BD0 mov edx,eax
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00007D46 66C1EA10 shr edx,0x10
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00007D4A F7761A div word [bp+NumberOfHeads]
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00007D4D 86D6 xchg dl,dh
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00007D4F 8A5640 mov dl,[bp+BootDrive]
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00007D52 8AE8 mov ch,al
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00007D54 C0E406 shl ah,0x6
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00007D57 0ACC or cl,ah
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00007D59 B80102 mov ax,0x201
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00007D5C CD13 int 0x13
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00007D5E 6661 popad
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00007D60 0F8254FF jc near print_disk_error_message
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00007D64 81C30002 add bx,0x200
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00007D68 6640 inc eax
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00007D6A 49 dec cx
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00007D6B 0F8571FF jnz near read_sectors
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00007D6F C3 ret
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NTLDR db 'NTLDR '
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filler times 49 db 0
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NTLDR_ERR db 0dh,0ah,'NTLDR is missing',0ffh
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DISK_ERR db 0dh,0ah,'Disk error',0ffh
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RESTART_ERR db 0dh,0ah,'Press any key to restart',0dh,0ah
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more_filler times 16 db 0
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NTLDR_offset_from_0x7d00 db 0
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NTLDR_ERR_offset_from_0x7d00 db 0ach
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DISK_ERR_offset_from_0x7d00 db 0bfh
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RESTART_ERR_offset_from_0x7d00 db 0cch
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dw 0
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2001-06-20 20:31:35 +00:00
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dw 0aa55h
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;
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; And that ends the code that makes up the traditional boot sector
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; From here on out is a disassembly of the extra sector of boot
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; code required for a FAT32 volume. Win2k stores this code at
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; sector 13 on the file system.
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;
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00008000 660FB64610 movzx eax,byte [bp+NumberOfFats] ; Put the number of fats into eax
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00008005 668B4E24 mov ecx,[bp+SectorsPerFatBig] ; Put the count of sectors per fat into ecx
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00008009 66F7E1 mul ecx ; Multiply them, edx:eax = (eax * ecx)
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0000800C 6603461C add eax,[bp+HiddenSectors] ; Add the hidden sectors to eax
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00008010 660FB7560E movzx edx,word [bp+ReservedSectors] ; Put the count of reserved sectors into edx
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00008015 6603C2 add eax,edx ; Add it to eax
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00008018 668946FC mov [bp-0x4],eax ; eax now contains the start of the data area, so save it for later
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0000801C 66C746F4FFFFFFFF mov dword [bp-0xc],0xffffffff ; Save 0xffffffff for later??
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00008024 668B462C mov eax,[bp+RootDirStartCluster] ; Put the starting cluster of the root directory into eax
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00008028 6683F802 cmp eax,byte +0x2 ; Check and see if the root directory starts at cluster 2 or above
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0000802C 0F82A6FC jc near print_ntldr_error_message ; If not exit with error
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00008030 663DF8FFFF0F cmp eax,0xffffff8 ; Check and see if the root directory start cluster is and end of cluster chain indicator
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00008036 0F839CFC jnc near print_ntldr_error_message ; If so exit with error
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search_root_directory_cluster:
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0000803A 6650 push eax ; Save root directory start cluster on stack
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0000803C 6683E802 sub eax,byte +0x2 ; Adjust it because the first two fat entries are unused so the third entry marks the first data area cluster
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00008040 660FB65E0D movzx ebx,byte [bp+SectsPerCluster] ; Put the number of sectors per cluster in ebx
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00008045 8BF3 mov si,bx ; Now store it also in si register
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00008047 66F7E3 mul ebx ; Multiply sectors per cluster with root directory start cluster
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0000804A 660346FC add eax,[bp-0x4] ; Add the start sector of the data area
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read_directory_sector:
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0000804E BB0082 mov bx,0x8200 ; We now have the start sector of the root directory, so load it to 0x8200
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00008051 8BFB mov di,bx ; Put the address of the root directory sector in di also
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00008053 B90100 mov cx,0x1 ; Read one sector
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00008056 E887FC call read_sectors ; Perform the read
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check_entry_for_ntldr:
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00008059 382D cmp [di],ch ; Check the first byte of the root directory entry for zero
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0000805B 741E jz ntldr_not_found ; If so then NTLDR is missing so exit with error
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0000805D B10B mov cl,0xb ; Put the value 11 in cl so we can compare an 11-byte filename
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0000805F 56 push si ; Save si (which contains the number of sectors per cluster)
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00008060 BE707D mov si,NTLDR ;0x7d70 ; Check and see if "NTLDR" is the first file entry
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00008063 F3A6 repe cmpsb ; Do the compare
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00008065 5E pop si ; Restore sectors per cluster into si
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00008066 741B jz ntldr_found ; If we found it then continue, else check next entry
|
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00008068 03F9 add di,cx ; Add 0 to di? the next entry is 0x15 bytes away
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0000806A 83C715 add di,byte +0x15 ; Add 0x15 to di
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0000806D 3BFB cmp di,bx ; Check to see if we have reached the end of our sector we loaded, read_sectors sets bx = end address of data loaded
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0000806F 72E8 jc check_entry_for_ntldr ; If we haven't reached the end then check the next entry
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00008071 4E dec si ; decrement si, si holds the number of sectors per cluster
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00008072 75DA jnz read_directory_sector ; If it's not zero then search the next sector for NTLDR
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00008074 6658 pop eax ; If we got here that means we didn't find NTLDR in the previous root directory cluster, so restore eax with the start cluster
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00008076 E86500 call get_fat_entry ; Get the next cluster in the fat chain
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00008079 72BF jc search_root_directory_cluster ; If we reached end-of-file marker then don't jump, otherwise continue search
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ntldr_not_found:
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0000807B 83C404 add sp,byte +0x4
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0000807E E955FC jmp print_ntldr_error_message
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ntldr_load_segment_address dw 0x2000
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ntldr_found:
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00008083 83C404 add sp,byte +0x4 ; Adjust stack to remove root directory start cluster
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00008086 8B7509 mov si,[di+0x9] ; Put start cluster high word in si
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00008089 8B7D0F mov di,[di+0xf] ; Put start cluster low word in di
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0000808C 8BC6 mov ax,si ; Put high word in ax
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0000808E 66C1E010 shl eax,0x10 ; Shift it into position
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00008092 8BC7 mov ax,di ; Put low word in ax, now eax contains start cluster of NTLDR
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00008094 6683F802 cmp eax,byte +0x2 ; Check and see if the start cluster of NTLDR starts at cluster 2 or above
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00008098 0F823AFC jc near print_ntldr_error_message ; If not exit with error
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0000809C 663DF8FFFF0F cmp eax,0xffffff8 ; Check and see if the start cluster of NTLDR is and end of cluster chain indicator
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000080A2 0F8330FC jnc near print_ntldr_error_message ; If so exit with error
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load_next_ntldr_cluster:
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000080A6 6650 push eax ; Save NTLDR start cluster for later
|
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000080A8 6683E802 sub eax,byte +0x2 ; Adjust it because the first two fat entries are unused so the third entry marks the first data area cluster
|
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000080AC 660FB64E0D movzx ecx,byte [bp+SectsPerCluster] ; Put the sectors per cluster into ecx
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000080B1 66F7E1 mul ecx ; Multiply sectors per cluster by the start cluster, we now have the logical start sector
|
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|
000080B4 660346FC add eax,[bp-0x4] ; Add the start of the data area logical sector
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|
000080B8 BB0000 mov bx,0x0 ; Load NTLDR to offset zero
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|
000080BB 06 push es ; Save es
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000080BC 8E068180 mov es,[ntldr_load_segment_address] ; Get the segment address to load NTLDR to
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000080C0 E81DFC call read_sectors ; Load the first cluster
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000080C3 07 pop es ; Restore es
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|
000080C4 6658 pop eax ; Restore eax to NTLDR start cluster
|
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|
000080C6 C1EB04 shr bx,0x4 ; bx contains the amount of data we transferred, so divide it by 16
|
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|
|
000080C9 011E8180 add [ntldr_load_segment_address],bx ; Add that value to the segment
|
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|
|
000080CD E80E00 call get_fat_entry ; Get the next cluster in eax
|
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|
000080D0 0F830200 jnc near jump_to_ntldr ; If we have reached the end of file then lets get to NTLDR
|
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|
000080D4 72D0 jc load_next_ntldr_cluster ; If not, then load another cluster
|
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|
jump_to_ntldr:
|
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|
|
000080D6 8A5640 mov dl,[bp+BootDrive] ; Put the boot drive in dl
|
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|
|
000080D9 EA00000020 jmp 0x2000:0x0 ; Jump to NTLDR
|
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|
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|
|
get_fat_entry:
|
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|
|
000080DE 66C1E002 shl eax,0x2 ; Multiply cluster by 4
|
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000080E2 E81100 call load_fat_sector ; Load the fat sector
|
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|
000080E5 26668B01 mov eax,[es:bx+di] ; Get the fat entry
|
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|
000080E9 6625FFFFFF0F and eax,0xfffffff ; Mask off the most significant 4 bits
|
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000080EF 663DF8FFFF0F cmp eax,0xffffff8 ; Compare it to end of file marker to set the flags correctly
|
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|
000080F5 C3 ret ; Return to caller
|
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|
load_fat_sector:
|
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|
|
|
000080F6 BF007E mov di,0x7e00 ; We will load the fat sector to 0x7e00
|
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|
000080F9 660FB74E0B movzx ecx,word [bp+SectsPerCluster] ; Get the sectors per cluster
|
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|
000080FE 6633D2 xor edx,edx ; We will divide (cluster * 4) / sectorspercluster
|
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|
00008101 66F7F1 div ecx ; eax is already set before we get to this routine
|
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00008104 663B46F4 cmp eax,[bp-0xc] ; Compare eax to 0xffffffff (initially, we set this value later)
|
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|
|
00008108 743A jz load_fat_sector_end ; If it is the same return
|
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|
0000810A 668946F4 mov [bp-0xc],eax ; Update that value
|
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|
0000810E 6603461C add eax,[bp+HiddenSectors] ; Add the hidden sectors
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|
00008112 660FB74E0E movzx ecx,word [bp+ReservedSectors] ; Add the reserved sectors
|
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|
00008117 6603C1 add eax,ecx ; To the hidden sectors + the value we computed earlier
|
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|
0000811A 660FB75E28 movzx ebx,word [bp+ExtendedFlags] ; Get extended flags and put into ebx
|
2001-07-06 22:05:05 +00:00
|
|
|
0000811F 83E30F and bx,byte +0xf ; Mask off upper 8 bits
|
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|
00008122 7416 jz load_fat_sector_into_memory ; If fat is mirrored then skip fat calcs
|
2001-06-20 20:31:35 +00:00
|
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|
00008124 3A5E10 cmp bl,[bp+NumberOfFats] ; Compare bl to number of fats
|
|
|
|
|
00008127 0F83ABFB jnc near print_ntldr_error_message ; If bl is bigger than numfats exit with error
|
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|
|
0000812B 52 push dx ; Save dx
|
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|
|
|
0000812C 668BC8 mov ecx,eax ; Put the current fat sector offset into ecx
|
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|
|
|
0000812F 668B4624 mov eax,[bp+SectorsPerFatBig] ; Get the number of sectors occupied by one fat
|
|
|
|
|
00008133 66F7E3 mul ebx ; Multiplied by the active fat index
|
|
|
|
|
00008136 6603C1 add eax,ecx ; Add the current fat sector offset
|
|
|
|
|
00008139 5A pop dx ; Restore dx
|
|
|
|
|
load_fat_sector_into_memory:
|
|
|
|
|
0000813A 52 push dx ; Save dx, what is so important in dx??
|
|
|
|
|
0000813B 8BDF mov bx,di ; Put 0x7e00 in bx
|
|
|
|
|
0000813D B90100 mov cx,0x1 ; Load one sector
|
|
|
|
|
00008140 E89DFB call read_sectors ; Perform the read
|
|
|
|
|
00008143 5A pop dx ; Restore dx
|
|
|
|
|
load_fat_sector_end:
|
|
|
|
|
00008144 8BDA mov bx,dx ; Put it into bx, what is this value??
|
|
|
|
|
00008146 C3 ret ; Return
|
|
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|
|
|
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|
00008147 0000 add [bx+si],al
|
|
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|
|
00008149 0000 add [bx+si],al
|
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|
0000814B 0000 add [bx+si],al
|
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|
0000814D 0000 add [bx+si],al
|
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|
0000814F 0000 add [bx+si],al
|
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|
00008151 0000 add [bx+si],al
|
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|
00008153 0000 add [bx+si],al
|
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|
00008155 0000 add [bx+si],al
|
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|
00008157 0000 add [bx+si],al
|
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|
00008159 0000 add [bx+si],al
|
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|
0000815B 0000 add [bx+si],al
|
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|
0000815D 0000 add [bx+si],al
|
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|
0000815F 0000 add [bx+si],al
|
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|
00008161 0000 add [bx+si],al
|
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|
00008163 0000 add [bx+si],al
|
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|
00008165 0000 add [bx+si],al
|
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|
00008167 0000 add [bx+si],al
|
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|
00008169 0000 add [bx+si],al
|
|
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|
|
0000816B 0000 add [bx+si],al
|
|
|
|
|
0000816D 0000 add [bx+si],al
|
|
|
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|
0000816F 0000 add [bx+si],al
|
|
|
|
|
00008171 0000 add [bx+si],al
|
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|
|
00008173 0000 add [bx+si],al
|
|
|
|
|
00008175 0000 add [bx+si],al
|
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|
00008177 0000 add [bx+si],al
|
|
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|
|
00008179 0000 add [bx+si],al
|
|
|
|
|
0000817B 0000 add [bx+si],al
|
|
|
|
|
0000817D 0000 add [bx+si],al
|
|
|
|
|
0000817F 0000 add [bx+si],al
|
|
|
|
|
00008181 0000 add [bx+si],al
|
|
|
|
|
00008183 0000 add [bx+si],al
|
|
|
|
|
00008185 0000 add [bx+si],al
|
|
|
|
|
00008187 0000 add [bx+si],al
|
|
|
|
|
00008189 0000 add [bx+si],al
|
|
|
|
|
0000818B 0000 add [bx+si],al
|
|
|
|
|
0000818D 0000 add [bx+si],al
|
|
|
|
|
0000818F 0000 add [bx+si],al
|
|
|
|
|
00008191 0000 add [bx+si],al
|
|
|
|
|
00008193 0000 add [bx+si],al
|
|
|
|
|
00008195 0000 add [bx+si],al
|
|
|
|
|
00008197 0000 add [bx+si],al
|
|
|
|
|
00008199 0000 add [bx+si],al
|
|
|
|
|
0000819B 0000 add [bx+si],al
|
|
|
|
|
0000819D 0000 add [bx+si],al
|
|
|
|
|
0000819F 0000 add [bx+si],al
|
|
|
|
|
000081A1 0000 add [bx+si],al
|
|
|
|
|
000081A3 0000 add [bx+si],al
|
|
|
|
|
000081A5 0000 add [bx+si],al
|
|
|
|
|
000081A7 0000 add [bx+si],al
|
|
|
|
|
000081A9 0000 add [bx+si],al
|
|
|
|
|
000081AB 0000 add [bx+si],al
|
|
|
|
|
000081AD 0000 add [bx+si],al
|
|
|
|
|
000081AF 0000 add [bx+si],al
|
|
|
|
|
000081B1 0000 add [bx+si],al
|
|
|
|
|
000081B3 0000 add [bx+si],al
|
|
|
|
|
000081B5 0000 add [bx+si],al
|
|
|
|
|
000081B7 0000 add [bx+si],al
|
|
|
|
|
000081B9 0000 add [bx+si],al
|
|
|
|
|
000081BB 0000 add [bx+si],al
|
|
|
|
|
000081BD 0000 add [bx+si],al
|
|
|
|
|
000081BF 0000 add [bx+si],al
|
|
|
|
|
000081C1 0000 add [bx+si],al
|
|
|
|
|
000081C3 0000 add [bx+si],al
|
|
|
|
|
000081C5 0000 add [bx+si],al
|
|
|
|
|
000081C7 0000 add [bx+si],al
|
|
|
|
|
000081C9 0000 add [bx+si],al
|
|
|
|
|
000081CB 0000 add [bx+si],al
|
|
|
|
|
000081CD 0000 add [bx+si],al
|
|
|
|
|
000081CF 0000 add [bx+si],al
|
|
|
|
|
000081D1 0000 add [bx+si],al
|
|
|
|
|
000081D3 0000 add [bx+si],al
|
|
|
|
|
000081D5 0000 add [bx+si],al
|
|
|
|
|
000081D7 0000 add [bx+si],al
|
|
|
|
|
000081D9 0000 add [bx+si],al
|
|
|
|
|
000081DB 0000 add [bx+si],al
|
|
|
|
|
000081DD 0000 add [bx+si],al
|
|
|
|
|
000081DF 0000 add [bx+si],al
|
|
|
|
|
000081E1 0000 add [bx+si],al
|
|
|
|
|
000081E3 0000 add [bx+si],al
|
|
|
|
|
000081E5 0000 add [bx+si],al
|
|
|
|
|
000081E7 0000 add [bx+si],al
|
|
|
|
|
000081E9 0000 add [bx+si],al
|
|
|
|
|
000081EB 0000 add [bx+si],al
|
|
|
|
|
000081ED 0000 add [bx+si],al
|
|
|
|
|
000081EF 0000 add [bx+si],al
|
|
|
|
|
000081F1 0000 add [bx+si],al
|
|
|
|
|
000081F3 0000 add [bx+si],al
|
|
|
|
|
000081F5 0000 add [bx+si],al
|
|
|
|
|
000081F7 0000 add [bx+si],al
|
|
|
|
|
000081F9 0000 add [bx+si],al
|
|
|
|
|
000081FB 0000 add [bx+si],al
|
|
|
|
|
000081FD 0055AA add [di-0x56],dl ; We can't forget the infamous boot signature
|
