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Index > OS Construction > Boot CD-Rom code and how to create file ISO ?

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Tos_2011



Joined: 02 Oct 2010
Posts: 4
Tos_2011
thank ,I understood Asm and C.
I want to live CD.I work with NASM
Code:
[org 0x7C00]
start: ;some code.example:FAT12,printstring,...
Times  510-($-$$) db 0
Dw AA55    

How to code for LiveCD And command make file.iso ?
Post 08 Nov 2010, 09:58
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bitRAKE



Joined: 21 Jul 2003
Posts: 3044
Location: vpcmipstrm
bitRAKE
I thought someone here did a bootable "El Torito" spec image from FASM. Yet, my quick search didn't turn up anything. Lots of result on Google. First one seems most helpful...

http://forum.osdev.org/viewtopic.php?f=1&t=20561
Post 08 Nov 2010, 15:11
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rugxulo



Joined: 09 Aug 2005
Posts: 2341
Location: Usono (aka, USA)
rugxulo
Jorg Schilling's MKISOFS.EXE should work to create one. Alexei Frounze's FAT library has a DOS/DJGPP compile. (Obviously more popular OSes have 'em too, somewhere.)
Post 08 Nov 2010, 15:59
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mindcooler



Joined: 01 Dec 2009
Posts: 423
Location: Västerås, Sweden
mindcooler

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Post 08 Nov 2010, 16:51
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cod3b453



Joined: 25 Aug 2004
Posts: 619
cod3b453
You can make the ISO from FASM - note that the sector size is not 512 bytes, so it's better to use a symbolic constant rather than hardcoding if you want to have multiple boot images of the same code.

iso.asm
Code:
        ; Output
        format binary as 'iso'


        ; Macros
macro @align_null a
 {
        repeat ((a - ($ mod a)) mod a)
                db NULL
        end repeat
 }

macro iso9660_timestamp yr,mo,da,hr,mi,sc,off
 {
        db (yr - 1900)
        db mo
        db da

        db hr
        db mi
        db sc

        db off
 }

macro iso9660_dw v
 {
        dw v

        db (v shr 8)
        db (v and 0xFF)
 }

macro iso9660_dd v
 {
        dd v

        db ((v shr 24) and 0xFF)
        db ((v shr 16) and 0xFF)
        db ((v shr  8) and 0xFF)
        db (v and 0xFF)
 }

macro iso9660_ddx v
 {
        db ((v shr 24) and 0xFF)
        db ((v shr 16) and 0xFF)
        db ((v shr  8) and 0xFF)
        db (v and 0xFF)
 }

        ; Constants
        DISK_SIZE_SECTOR        equ 2048

        NULL                    equ 0

        IS09660_VDT_BOOTRECORD equ 0x00
        IS09660_VDT_PRIMARY equ 0x01
        IS09660_VDT_SUPPLEMENTARY equ 0x02
        IS09660_VDT_PARTITION equ 0x03
        IS09660_VDT_TERMINATOR equ 0xFF

        ; ISO image
        rb (16 * DISK_SIZE_SECTOR)
        db IS09660_VDT_PRIMARY
        db 'CD001'
        db 0x01
        db 0
        db '                                '
        db '                                '
        iso9660_dd 0
        iso9660_dd (iso9660.boot / DISK_SIZE_SECTOR)
        dd 0,0,0,0,0,0,0,0
        iso9660_dw 1
        iso9660_dw 1
        iso9660_dw DISK_SIZE_SECTOR
        iso9660_dd 10
        dd (iso9660.plpath / DISK_SIZE_SECTOR)
        dd 0
        iso9660_ddx (iso9660.pmpath / DISK_SIZE_SECTOR)
        dd 0
        db 0x22
        db 0x00
        iso9660_dd (iso9660.pdr / DISK_SIZE_SECTOR)
        iso9660_dd DISK_SIZE_SECTOR
        iso9660_timestamp 2000,1,1,0,0,0,0
        db 0x02
        db 0x00
        db 0x00
        iso9660_dw 0
        db 0x01
        db 0x00
        dq 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
        dq 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
        dq 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
        dq 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
        dq 0,0,0,0
        dd 0
        db 0
        dq 0,0,0,0
        dd 0
        db 0
        dq 0,0,0,0
        dd 0
        db 0
        db '2000010100000000',0
        db '2000010100000000',0
        dd 0,0,0,0
        db 0
        dd 0,0,0,0
        db 0
        db 0x01
        @align_null DISK_SIZE_SECTOR

    iso9660.brd:

        db IS09660_VDT_BOOTRECORD
        db 'CD001'
        db 0x01
        db 'EL TORITO SPECIFICATION',0
        dd 0,0
        dd 0,0,0,0,0,0,0,0
        dd (iso9660.bootcat / DISK_SIZE_SECTOR)
        @align_null DISK_SIZE_SECTOR

    iso9660.svd:

        db IS09660_VDT_SUPPLEMENTARY
        db 'CD001'
        db 0x01
        db 0x00
        dd 0,0,0,0,0,0,0,0
        db 0,'c',0,'o',0,'d',0,'3',0,'b',0,'4',0,'5',0,'3'
        db 0,'b',0,'o',0,'o',0,'t',0,' ',0,'c',0,'d',0,' '
        iso9660_dd 0
        iso9660_dd (iso9660.boot / DISK_SIZE_SECTOR)
        db 0x25,0x2F,0x45,0
        dd 0,0,0
        dd 0,0,0,0
        iso9660_dw 1
        iso9660_dw 1
        iso9660_dw DISK_SIZE_SECTOR
        iso9660_dd 10
        dd (iso9660.slpath / DISK_SIZE_SECTOR)
        dd 0
        iso9660_ddx (iso9660.smpath / DISK_SIZE_SECTOR)
        dd 0
        db 0x22
        db 0x00
        iso9660_dd (iso9660.sdr / DISK_SIZE_SECTOR)
        iso9660_dd  DISK_SIZE_SECTOR
        iso9660_timestamp 2000,1,1,0,0,0,0
        db 0x02
        db 0x00
        db 0x00
        iso9660_dw 0
        db 0x01
        db 0x00
        dq 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
        dq 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
        dq 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
        dq 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
        dq 0,0,0,0
        dd 0
        db 0
        dq 0,0,0,0
        dd 0
        db 0
        dq 0,0,0,0
        dd 0
        db 0
        db '2000010100000000',0
        db '2000010100000000',0
        dd 0,0,0,0
        db 0
        dd 0,0,0,0
        db 0
        db 0x01
        @align_null DISK_SIZE_SECTOR

    iso9660.tvd:

        db IS09660_VDT_TERMINATOR
        db 'CD001'
        db 0x01
        @align_null DISK_SIZE_SECTOR

    iso9660.boot:

        ; The boot sector
        include 'boot.asm'

        org (21 * DISK_SIZE_SECTOR)

    iso9660.bootcat:

        db 0x01
        db 0x00
        dw 0
        dd 0,0,0,0,0,0
        db 0xAA,0x55
        db 0x55,0xAA
        db 0x88
        db 0x00
        dw 0x0000
        db 0x00
        db 0
        dw 0x0004
        dd (iso9660.boot / DISK_SIZE_SECTOR)
        @align_null DISK_SIZE_SECTOR

    iso9660.pdr:

        db 0x22
        db 0x00
        iso9660_dd (iso9660.pdr / DISK_SIZE_SECTOR)
        iso9660_dd DISK_SIZE_SECTOR
        iso9660_timestamp 2000,1,1,0,0,0,0
        db 0x02
        db 0
        db 0
        iso9660_dw 0
        db 0x01
        db 0x00

        db 0x22
        db 0x00
        iso9660_dd (iso9660.pdr / DISK_SIZE_SECTOR)
        iso9660_dd 2048
        iso9660_timestamp 2000,1,1,0,0,0,0
        db 0x02
        db 0
        db 0
        iso9660_dw 0
        db 0x01
        db 0x01
        @align_null DISK_SIZE_SECTOR

    iso9660.plpath:

        db 0x01
        db 0x00
        dd (iso9660.pdr / DISK_SIZE_SECTOR)
        dw 1
        dw 0
        @align_null DISK_SIZE_SECTOR

    iso9660.pmpath:

        db 0x01
        db 0x00
        iso9660_ddx (iso9660.pdr / DISK_SIZE_SECTOR)
        iso9660_dw 1
        iso9660_dw 0
        @align_null DISK_SIZE_SECTOR

    iso9660.sdr:

        db 0x22
        db 0x00
        iso9660_dd (iso9660.sdr / DISK_SIZE_SECTOR)
        iso9660_dd DISK_SIZE_SECTOR
        iso9660_timestamp 2000,1,1,0,0,0,0
        db 0x02
        db 0
        db 0
        iso9660_dw 0
        db 0x01
        db 0x00

        db 0x22
        db 0x00
        iso9660_dd (iso9660.sdr / DISK_SIZE_SECTOR)
        iso9660_dd DISK_SIZE_SECTOR
        iso9660_timestamp 2000,1,1,0,0,0,0
        db 0x02
        db 0
        db 0
        iso9660_dw 0
        db 0x01
        db 0x01
        @align_null DISK_SIZE_SECTOR

    iso9660.slpath:

        db 0x01
        db 0x00
        dd (iso9660.sdr / DISK_SIZE_SECTOR)
        dw 1
        dw 0
        @align_null DISK_SIZE_SECTOR

    iso9660.smpath:

        db 0x01
        db 0x00
        iso9660_ddx (iso9660.sdr / DISK_SIZE_SECTOR)
        iso9660_dw 1
        iso9660_dw 0
        @align_null DISK_SIZE_SECTOR

        ; Other disk data can go here
    

boot.asm
Code:
        org 0x7C00

        cli
        jmp 0:@f

    @@:

        mov ax,0xB800
        mov ds,ax
        mov word [ds:0],'Hi'

        xor ah,ah
        int 0x16

        times (0x7C00 + DISK_SIZE_SECTOR - $ - 2) db 0
        dw 0xAA55    
(apologies -- this is a merge of 5/6 files to save space)

Hope that helps Cool
Post 08 Nov 2010, 19:25
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egos



Joined: 10 Feb 2009
Posts: 144
egos
I'm still developing mkisofs.inc for fasm and boot code for cdfs (iso9660). You can take current version of mkisofs.inc here, but be careful because it's experimental version. In boot code now I use the method that's realized in GRUB. I'm storing position and size of the loading file in boot code. I can show basic routines from my boot code.

cdrom.asc
Code:
include "mkimage/mkisofs.inc"

rb 16*2048 ; system area
primvd
bootrec
termvd
bootcat
lpt
mpt

defdir root
{
dent kernel,"KERNEL.BIN",FA_DEF
dent readme,"README.TXT",FA_DEF
}

stof boot,"bootcode.bin" ; boot is reserved name for boot code
store dword kernel_base/2048 at boot_base+16
store dword kernel_size at boot_base+20
stod root,root ; root is reserved name for root directory
stof kernel,"content/kernel.bin"
stof kernel,"content/readme.txt"

fixvol    


Code:
;
; ax:cx - starting sector number
; dx - file size in kilobytes
; bx - buffer base in paragraphs (will be recalculated)
;
loadfile:
  mov word [dapack.lba],ax
  mov word [dapack.lba+2],cx
  mov ax,SPB
  shr dx,1
  pushf
  jmp short @f
.read1:
  xor dx,dx
.read2:
  push dx
  call read
  pop dx
  push ax
  aam 2
  ror al,1
  add bx,ax
  pop ax
@@:
  sub dx,ax
  jnc short .read2
  add ax,dx
  jnz short .read1
  popf
  jnc short @f
  push bx
  mov bx,BUFSEG
  inc ax
  call read
  pop bx
  mov es,bx
  add bx,40h
  mov si,BUFSEG shl 4
  xor di,di
  mov cx,512
  rep movsw
@@:
  ret
tryagain:
  dec ah
  jnz short @f
  call putstr
  db 13,10,"Disk read error",0
bootfailure:
  call putstr
  db 13,10,"Disk boot failure",0
;
; dword [dapack.lba] - starting sector number (will recalculated)
; ax - number of sectors to read (not abave 127)
; bx - buffer base in paragraphs
;
read:
  mov word [dapack.pointer+2],bx
  mov ah,MAXTRIES
  push bx
@@:
  mov si,dapack
  mov [dapack.length],al
  mov dl,[drive]
  push ax
  mov ah,42h
  int 13h
  pop ax
  jc short tryagain
  pop bx
  cbw
  add word [dapack.lba],ax
  adc word [dapack.lba+2],0
  jc short bootfailure
  ret    


Description:
Download
Filename: mkisofs.zip
Filesize: 1.02 KB
Downloaded: 245 Time(s)

Post 09 Nov 2010, 12:45
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