While I love using
Arduino, I would never use one in
line with my rig in a mission critical situation. They may work fine, but are not heavily tested for reliability, and there would be no vendor support. Look at Pathway and
Enttec products.
I've got a nano running in my wall right now for architectural control. While I agree show dependent applications might not be sound, there's a lot to be said for the ATMega chips with no boot time and low
power needs. Mine's been running now for a few months with nary an issue. I'm planning to do a
bit of a writeup on it since it has proven itself to be a useful addition to our space.
The
shield uses a serial data
line from the
Arduino and just houses the RS-485 chip that converts the
DMX into the correct balanced
protocol. Most of the shields
enable the
RDM functionality, but I haven't seen definitively that any of the software libraries for
Arduino actually support it. Most stuff I found online gets to the
point of sending data, but not much past that. I think it's possible, but I can't speak to that
point. I ended up buying a
shield, but it didn't have isolation so I made my own which added a DC-DC converter and an optocoupler. When I get some time I'll put a
build guide together.
Thinking further, to use one to solve OP's problem would probably require multiple shields since you'd need one to act as a receiver and the other as a master for the next
leg and you'd want to electrically isolate both runs. It would also be tricky with coding and I'm not sure if the
Arduino could handle processing one stream and then resending with coding that would get it to hold on signal loss. But as a simple
send device I've found it particularly useful.