Scanning the root dir fails...

[Berry]

Hello,

I find it difficult to find and scan the root-dir. I find the root-dir this way:

;bereken de LBA
mov ax, [num_fats]
mov bx, [sectors_per_fat]
mul bx ;num_fats * sectors_per_fat...
add ax, [num_boot_sectors] ;... + num_boot_sectors

push ax ;zet de LBA op de stack

;bereken aantal in te lezen sectors
mov ax, [num_root_dir_ents]
mov bx, 0x20
mul bx ;num_root_dir_ents * 0x20...
mov bx, [bytes_per_sector]
div bx ;... / bytes_per_sector
mov cx, ax ;cx = aantal in te lezen sectors

pop ax ;ax = LBA

mov bx, 0x0200
mov es, bx ;segment:
mov bx, 0x0000 ;offset van de root_dir

call load_sector ;laad de sectors van de floppy

load_sector resets the floppy drive, calls LBAtoCHS and loads the sectors where the root-dir is. I then scan the root-dir for

second.bin db 'SECOND  BIN',0

it doesn't find it... I use cmpsb to compare the string... Load the string in like this:

mov si, second.bin_file ;de string om te zoeken
mov bx, 0x0200
mov es, bx ;waar te zoeken
xor di, di ;di = 0

than call scan_root_dir

is anything wrong with this? Debugging for 2 days now...

[Berry]

Ow, yes ofcourse! Your english...

;calculate the LBA
mov ax, [num_fats]
mov bx, [sectors_per_fat]
mul bx ;num_fats * sectors_per_fat...
add ax, [num_boot_sectors] ;... + num_boot_sectors

push ax ;push the LBA to the stack

;calculate number of sectors to read
mov ax, [num_root_dir_ents]
mov bx, 0x20
mul bx ;num_root_dir_ents * 0x20...
mov bx, [bytes_per_sector]
div bx ;... / bytes_per_sector
mov cx, ax ;cx = # sectors to read
pop ax ;ax = LBA

mov bx, 0x0200
mov es, bx ;segment:
mov bx, 0x0000 ;offset of the root_dir

call load_sector ;load the sectors from the root-dir

load_sector resets the floppy drive, calls LBAtoCHS and loads the sectors where the root-dir is. I then scan the root-dir for

second.bin db 'SECOND  BIN',0

it doesn't find it... I use cmpsb to compare the string... Load the string in like this:

mov si, second.bin_file ;the string to search
mov bx, 0x0200
mov es, bx ;where to search
xor di, di ;di = 0

then call scan_root_dir

If there's not anything wrong with this, please post that, then I will post all my code

[ASHLEY4]

Berry go here:

  http://alexfru.chat.ru/epm.html

And down load "bootprog.zip" in is the code to do what you want (Coded in nasm) compear it with yours, and see were you are going wrong.

ASHLEY4.