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[on:]

I have just finished a shield intended for DMX or RS485 based network. It has two RJ45 ports and two Phoenix type screw connectors. All A and B terminals of RS485 are connected together despite their label of IN and OUT

It can be used for DMX application, pins are configured according to DMX channel one, ie, pin 1 to DMX Data+ (and to RS485 A on the driver) and pin 2 to DMX Data- (and to RS485 B on the driver), pin 3 and pin 6 are pass-through.

Another intention of this shield is for home automation where remote switches or relays can be controlled via RS485 communication lines due to its high noise immunity over long distance. In this regard, power can be transmitted over RJ45 cable (Cat 5 or Cat 6) using 4 and 5 pins (not used in DMX) as V+ and 7 and 8 as ground. Power can come from external power or from Arduino power supply (not recommended for real installation but can be used during development). Resettable thermal fuse rated 3A is used to protect the shield from accidental shorts.

When using RS485, it is much easier to use RJ45 cables because they are easier to source, cheap and can be found almost everywhere, and best of all in my mind is its plug-and-go feature.

[Reply #1 on:]

Congratulations, your board looks cool
I also develop a board using RS485 but in my case is not a shield, I was for a dedicated Temperature Sensor Bus topology.
Can you post your schematic?
   

[Reply #2 on:]

salve sono interessato a capire come fare a colloquiare arduino con dmx ma non sono pratico.
Mi spiego meglio cosa vorrei realizzare:

1) Usando una qualunque centralina DMX vorrei commandare due servi.
2) Usando una qualunque centralina DMX vorrei comandare lo zoom e messa fuco di una videocamera tramite LANC ( schema gia realizato con arduino)
3) eventuale luce