Probably true. I mentioned it because I've seen talk of "four-wire
RS-485", which is probably just RS-422, but I haven't examined it
closely enough to know that it isn't some hybrid beast.
There are. Greyhill uses them on their microDAQ controllers. For
hardware it is 422 but since it is a daisy chained buss it has a 485
command structure to take care of who is talking. They also can be
simply switched to a 2 wire interface for true 485 behavior.
Basically it is a hybrid beast and just means that your 485 software
can run with a 422 port.
