Int 13 Fn 12  - Hard Disk - Controller Ram Diagnostic (xt,ps)              [B]

   AH = 12h
   DL = drive number (80h = first, 81h = second hard disk)

Return: CF set on error
   CF clear if successful
   AH = status code (see #0166 at AH=01h)
   AL = 00h

See Also: AH=13h,AH=14h