Re: [ros-dev] [ros-diffs] [mbosma] 25283: Do not show "Press any key to boot from CD"-Message if there is no MBR on the hard drive.

[Klemens Friedl]

(forwarded for maarten bosma)


>   [03 Jan 07 16:03] * Morpheouss * i am here just to
> say, that change made 
in 25283 revision is not accurate
>   [03 Jan 07 16:04] * Morpheouss * it was introduced in
> windows 2000, and it 
fails when user have installed OS, MBR is not written, and OS
is bootable...
>   [03 Jan 07 16:05] * Morpheouss * eg. i use Linux and
> grub to boot it up
>  [03 Jan 07 16:05] * Morpheouss * and windows 2000 doesn't show this 
message and
boots up
>   [03 Jan 07 16:05] * Morpheouss * even if i wanted to
> boot linux
>  [03 Jan 07 16:06] * Morpheouss * so i don't think it was a good idea
>  [03 Jan 07 16:06] * Morpheouss * sometimes when i install windows i forget 
to eject
CD :P
>   [03 Jan 07 16:06] * Morpheouss * it was better done in
> my opinion
>  [03 Jan 07 16:07] * Morpheouss * when user could control it even MBR is 
not
written
>   [03 Jan 07 16:09] * Morpheouss * in my opinion it
> should be reverted 
Please comment.

>   Author: mbosma
>  Date: Wed Jan  3 17:33:41 2007
>  New Revision: 25283
>
>  URL: http://svn.reactos.org/svn/reactos?rev=25283&view=rev
>  Log:
>  Do not show "Press any key to boot from CD"-Message if there is no MBR on
the hard drive.
>  
>  Modified:
>      trunk/reactos/boot/freeldr/bootsect/isoboot.asm
>
>  Modified: trunk/reactos/boot/freeldr/bootsect/isoboot.asm
>  URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/bootsect/isob…
>  
==============================================================================
>   --- trunk/reactos/boot/freeldr/bootsect/isoboot.asm
> (original)
>  +++ trunk/reactos/boot/freeldr/bootsect/isoboot.asm Wed Jan  3 17:33:41 
2007
> @@ -139,13 +139,21 @@
>      jmp    .kbd_buffer_test
>  .kbd_buffer_empty:
>   
> -    ; Check if there is harddisk
> +    ; Check for MBR on harddisk
>      pusha
> -    mov    ax, 0800h
> +    mov    ax, 0201h
>      mov    dx, 0080h
> +    mov    cx, 0001h
> +    mov    bx, trackbuf
>      int    13h
>      popa
> -    jc    .boot_cdrom
> +    jc    .boot_cdrom ; could not read hdd
> +
> +    push ax
> +    mov ax, word [trackbuf]
> +    cmp ax, 0
> +    je    .boot_cdrom ; no boot sector found (hopefully there are no
weird bootsectors which begin with 0)
> +    pop ax
>   
>      ; Display the 'Press key'
message and wait for a maximum of 5 seconds
>      call    crlf