NIME

DMX Lightning System

Posted on November 27th, 2012 by Johann

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Last night I worked on putting together a simple DMX lighting system for my NIME instrument and performance called A Haunting.

I built a DMX shield for my Arduino by following the instructions from this website.

The parts needed are:

SN 75176 chip
Eliminator ED-15 DMX Lighting Dimmer Pack
100 ohm resistor
XML female jack
Assorted wires for connections
Some soldering skills

To start, I made a huge mistake at the beginning. Make sure to put the IC chip in the MIDDLE of your breadboard. If you don’t do this, all the pins will cross and once you start giving it power the chip will burn out, just like my first one did So don’t follow these pictures exactly. The chip should be over the middle the breadboard

So to begin, here is my breadboard, with my circuit for my NIME instrument. Pretty clean and simple

Here is the chip on the breadboard. Remember, don’t place it where I placed it! Put it in the MIDDLE of the breadboard, so that is is crossing over the bridge. I didn’t realize this until much later on

After

After wiring everything up, it should look like this. I eventually did more cleaning up down the road, and fixed a few connections. This is as far as I got before I got to looking for an XLR female jack.

So now I needed an XLR female jack, but I had none Luckily the junk shelf gods were smiling down on me, for I was able to find this!

Here is a closer one to show the details of the connections.

With advice from Ben Light, I was able to harvest one of these XLR female jacks to put to good use.

Back to the breadboard, I was able to connect the three pins from the circuit diagram to the three pins of the XLR female jack pretty easily.

It was at this point when I tried plugging the XLR female jack into the Eliminator ED-15 DMX Lighting Dimmer Pack when I realized something was up. I had Mark Kleback come give it a second look, and he helped me figure out that I needed to move my chip, as well as move some wires around. After a few good minutes of head scratching, we came to this:

Here is the final circuit, going into the Arduino!

Here is the test code I used.


#include <DmxSimple.h>

void setup() {
 DmxSimple.usePin(3);
  DmxSimple.maxChannel(4);
}

void loop() {
  int brightness;
  for (brightness = 0; brightness <= 255; brightness++) {
    DmxSimple.write(1, brightness); // Set DMX channel 1 to new value
    delay(10); // Wait 10ms
for (brightness = 255; brightness >= -; brightness--) {
    DmxSimple.write(1, brightness); // Set DMX channel 1 to new value
    delay(10); // Wait 10ms
  }
}

This example and others, including the DMXSimple library you are going to need to use, can be found at the DMXSimple website.

Here it is, working in action! The lightbulb is dimming on and off: