Int 14 Fn 23  - Multidos Plus - Get Port Status                            [S]

   AH = 23h
   DX = port number

Return: AH = line status (see #0230 at AH=03h)
   AL = modem status (see #0231 at AH=03h)

See Also: AH=03h,AH=07h"MultiDOS",AH=20h"MultiDOS"