INT 13 - HARD DISK - WRITE LONG SECTOR(S) (AT and later)
        AH = 0Bh
        AL = number of sectors
        CH = low eight bits of cylinder number
        CL = sector number (bits 5-0)
             high two bits of cylinder number (bits 7-6)
        DH = head number
        DL = drive number (80h = first, 81h = second)
        ES:BX -> data buffer
Return: CF clear if successful
        CF set on error
        AH = status (see AH=01h)
        AL = number of sectors transferred
Notes:  each sector's worth of data must be followed by four to seven bytes of
          error-correction information
        used for diagnostics only on PS/2 systems
SeeAlso: AH=0Ah