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# BIOS int 13h, function 02h, Read Sector.
# Input
# AH = 02h
# AL = number of sectors to read
# CH = track/cylinder
# CL = sector
# DL = disk (00h-7Fh floppy, 80h-FFh hard disk)
# DH = head
# ES:BX = segment:offset of buffer
# Output
# CF = 0 on success, 1 on failure with AH = failure code
# AL = number of sectors read
YES,bwat wrote:Not sure I understand the question, but, if I'm guessing right you want to map disks to identifiers used by the BIOS???
If so, there's a major clue in the documentation for BIOS int 13, function 2. Here's the documentation found in my bootstrap-loader's subroutine that uses that BIOS function.
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# BIOS int 13h, function 02h, Read Sector. # Input # AH = 02h # AL = number of sectors to read # CH = track/cylinder # CL = sector # DL = disk (00h-7Fh floppy, 80h-FFh hard disk) # DH = head # ES:BX = segment:offset of buffer # Output # CF = 0 on success, 1 on failure with AH = failure code # AL = number of sectors read
I want to get all disks IDbwat wrote:Not sure I understand the question, but, if I'm guessing right you want to map disks to identifiers used by the BIOS???
If so, there's a major clue in the documentation for BIOS int 13, function 2. Here's the documentation found in my bootstrap-loader's subroutine that uses that BIOS function.
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# BIOS int 13h, function 02h, Read Sector. # Input # AH = 02h # AL = number of sectors to read # CH = track/cylinder # CL = sector # DL = disk (00h-7Fh floppy, 80h-FFh hard disk) # DH = head # ES:BX = segment:offset of buffer # Output # CF = 0 on success, 1 on failure with AH = failure code # AL = number of sectors read
For example,We set BIOS first boot disk 1,Now,We use disk 1 to boot disk 2,How to determine their own disk 2 ID,It is guided by indirect.djmauretto wrote:0x80 Hard Disk (Boot)
0x81 Hard Disk
0x82 Hard Disk
Total 3 Hard Disk
For example,We set BIOS first boot disk 1,Now,We use disk 1 to boot disk 2,How to determine their own disk 2 ID,It is guided by indirect.
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XOR DX,DX
MOV ES,DX
MOV BX,0x7C00
MOV CX,1 ; Start Load from Sector #1
MOV DL,0x81 ; Hard Disk 2
MOV AX,0201H ; Read 1 Sector
INT 13H ; BIOS Disk
JC @Error
JMP 0x0000:0x7C00