(MESS) intv: converted the driver to use slot devices for
cartridges and implemented the IntelliVoice expansion and 
the Entertainment Computer System expansion as passthru 
devices. The official syntax to launch games requiring the
speech expansion is now
  mess intv -cart voice -cart2 gamename
which corresponds to mounting the IntelliVoice and plugging
the game cart in its subslot.  The official syntax to launch games 
requiring the ECS expansion is now instead
  mess intv -cart ecs -cart2 gamename
and
  mess intv -cart ecs -cart2 voice -cart3 gamename
if the game requires both expansions at once. For additional user 
friendliness, we also offer intvecs (which emulates an Intellivision
unit with both expansions added) and intvoice (which emulates 
an Intellivision with Intellivoice expansion added) drivers, where 
games can simply be mounted with the -cart media switch. [Fabio 
Priuli]