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I'm having some troubles reading sector 0 - head 0 - cylinder 1....
it outputs the wrong data....
but it does output the right data if I read sector 63 - head 0 - cylinder 0 before I read sector 0 - head 0 - cylinder 1...
(yes, it is on the disk in case you're wondering (I used dd for that), used the mbr for booting (windows-way))
So why doesn't it just read it inmidiatly?
reading a sector on cylinder 0, head 0, sec <63 works inmidiatly.
But reading sec 1 - cylinder 0 - head 0 doesn't..
any ideas why?

Here's the code:

code:
--------------------
bits 32
jmp s

err: mov ebx,0xb8000
     mov byte[es:ebx],'E'
     inc ebx
     mov byte[es:ebx],0x1F
     jmp hang



;===============================================
; read
;===============================================
s:

  mov dx,0x1f6
  mov ax,176      ; head+drive, second drive
  out dx,ax

  mov dx,0x1f2
  mov ax,1       ; 1 sector
  out dx,ax      

  mov dx,0x1f3
  mov ax,0        ; sector 0
  out dx,ax

  mov dx,0x1f4
  mov ax,1        ; cylinder 1
  out dx,ax

  mov dx,0x1f5
  mov ax,0        ; high cylinder = 0
  out dx,ax

  mov dx,0x1f7
  mov ax,0x20     ; read with retry :]
  out dx,ax

f:  in al,dx
    or al,1          ; error?
    je err      
    test al,8        ; are we still busy?
    jz f
    mov cx,0
    mov ebx,0xB8000
    jmp re

re: mov dx,0x1f0
    in ax,dx

    mov dl,al
    mov dh,ah

    mov byte[es:ebx],dl
    inc ebx
    mov byte[es:ebx],0x1F
    inc ebx

    mov byte[es:ebx],dh
    inc ebx
    mov byte[es:ebx],0x1F
    inc ebx

    inc cx
    cmp cx,512
    jne re
    jmp hang

hang: jmp hang          ; hang  
---------------------------------