INT 13 - HARD DISK - CONTROLLER RAM DIAGNOSTIC (XT,PS)

	AH = 12h
	DL = drive number (80h = first, 81h = second hard disk)
Return: CF set on error
	CF clear if successful
	AH = status code (see #00234 at AH=01h)
	AL = 00h
SeeAlso: AH=13h,AH=14h