Long Distance

Projects General Guidance
1

Hi all,
i am working on a theatre play, my system is simple: 7 switch connected to digital inputs, I used the 5v to make a simple "0/1".
In my computer, I treat the data with "Arduino2Max" to "Max4live" in Albeton live, it trigers events and sounds...
I need to be in the technical area with my Mac and of course my interface on stage (approximately 50 meters max).
I have tried a line extender (usb to rj45) but it does't work on so long distance.

In your opinion what is the most simple and reliable solution ?
Thank you

2

Use DMX, it was designed for theater.
playground.arduino.cc/Learning/DMX

3

Hmm, DMX isn't a cheap or simple setup really - we are, as far as I can tell, talking about connecting 7 switches on stage to an arduino which has its usb connector plugged into a computer in the control booth. All the software is already there for piping the pin state into the relevant
software. Also existing DMX setup will be running the other direction, from control booth to the stage!

Perhaps, given each switch is presumably low bandwidth, is to run a long ribbon cable from the Arduino to the switches on stage, and
add low-pass-filtering, schmidtt-triggers and protection circuitry at the Arduino end.

Alternatively the existing Arduino2Max will need rewriting and use RS485 link between 2 Arduinos, one on stage that multiplexes up the
pin states and sends it (perhaps with DMX protocol) via a RS485 transmitter to another Arduino in the control booth that reads the
incoming data and can handle the communications to Max.

4

DMX isn't a cheap or simple setup really

Yes it is, both cheap if you make it yourself, and simple to set up, just plug it in.

Also existing DMX setup will be running the other direction, from control booth to the stage!

DMX runs on wires, any other DMX setup is not going to interfere with it.

5

Thank you for your help, I'll do some research with these solution.
I will come back to you if you do not bother.

6

I would think you could use simple serial communication between the computer and the arduino.

7

what type of connection do you recommend ?
i need to stay in max/msp because it is the environment that I know best,I have very limited programming skills.
Currently my patch generates simple signals note on note off, each switch have his note.
About a "MIDI Breakout" with a midi booster ? I've seen a midi booster diy kit for the length.
Thx

8

I think of another solution, I need your advice, is it possible to:
1 - Boost output voltage at 9V or 12v
2 - Connect 4 XLR cable female from the arduino (8 connections one 9v or 12v out and seven digital in) to pass through the multicore down to the stagebox, than 4 XLR male to my interface on stage.
3 - and to regulate de voltage back to the arduino with something like this: 5V switching voltage regulator - 7805 replacements Do i need 7 of those ?

Additional difficulty is that a theater to another, the cable length will never be the same, between 20m and 50m.
I noticed that the voltage drop was very low via an XLR cable, for 1 loop of 50m I get 4.94v without external power.
I do not have enough cable to test with 8 length at home, i think the voltage drop will be bigger with 8 connection on 50m right ?
I need to connect my interface on stage to the mic inputs, as in every theater there a multicore that goes from stage to technical area, its the solution
the easiest I think.
That way i can keep it simple and have the arduino in USB next to my computer.
What do you think?
Sorry for my dumbness and the bad english...

9

that looks the least expensive: