12v accessory over 1 wire

Hello all,

Newby here to arduino. Looking for some assistance on programming and wiring an arduino setup to control multiple 12v accessories

Basically here it is. I have multiple 12v accessories on my truck (led lightbars mainly) and everything is hard wired to the point of almost multiple wires per accessories and now I'm trying to clean it up. I feel there is a way to have 2 arduinos on my truck. 1 in cab and one in bed, with multiple switches (or a touchscreen later on) on arduino in cab with a data and ground wire to arduino in bed where the arduino in bed can turn on the various devices based on what switch was initially pushed. Goal is to reduce the number of wires. I would like to have a strobe function available to certain devices and maybe control over rgb leds, from what I've read so far I'd want mosfets instead of relays.

Looking for some guidance on what hardware I'd need and why So I can look into it some more and post back with questions.


Ps if I'm in wrong group I apologize

Generally the communications that offer greater immunity to noise work in a balanced way. For this it is necessary to use 2 data wires.

The One Wire system has its limitations.

We recommend a maximum of 20 sensors on one 1-Wire extension regardless of wiring topology.


One of the most used systems for professional lighting is the DMX512. This system operates over an RS485 network. This network is balanced. Research the DMX512.

Q: Why do I need a RS-485 repeater for more than 32 nodes/devices?
A: A standard RS-485 node has a rated input impedance of 12Kohms. A standard RS-485 transmitter can't drive more than 32 devices and one pair of 120 ohm termination resistors. Simply adding an isolated repeater allows another 32 nodes to be connected.


That is much bulkier then I was hoping for but a good start. Are you aware if they make smaller versions?