INT 13 - HARD DISK - READ LONG SECTOR(S) (AT and later)
        AH = 0Ah
        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:  this function reads in four to seven bytes of error-correcting code
          along with each sector's worth of information
        data errors are not automatically corrected, and the read is aborted
          after the first sector with an ECC error
        used for diagnostics only on PS/2 systems
SeeAlso: AH=0Bh