Int 7F Fn C5  - Alloy Mw386 - Change Console Mode                          [N]

   AH = C5h
   AL = new console mode
       00h keyboard indirect
       01h keyboard direct
       02h data handshake enforced
       03h no data handshake

Return: CF clear if successful
       AL = prior console mode
   CF set on error (caller is not remote user)

Note:  modes 2 and 3 may be used for input through the console port; no video
     output should be performed in these modes