DMX
What is DMX?
DMX512 is a standard digital communication commonly used for stage lighting and effects. It was introduced as a method to standardize away from the proprietary methods used for lighting. It soon became the primary method used for stage and lighting effects, but it has also become common place for intelligent light systems found in the home and building automation.
The simple design and low-cost implementation of DMX however means that it doesn’t employ any automatic error checking or correction, this makes it unsuitable for hazardous applications such as pyrotechnics. False triggering on DMX may be caused by electromagnetic interference, static electricity discharges, improper cable termination, excessively long cables, or poor-quality cables.
Now you know about it, if you look carefully at the display, you may see some evidence of false triggering or glitches.
A DMX bus comprises of 512 channels (hence DMX512) and any given display may contain several DMX buses, or ‘universes’ – our MATRIX prop uses 12 universes as an example.
A DMX universe is intended to be used by stringing a number of devices together and each device in that chain may consume a number of the channels.
By example:
Prop 1 may use 4 channels and prop 2 may use 6 channels, totaling 4+6 = 10 channels of 512. There are 502 channels left available after the first 2 props are added.
The channels required are based on the prop developers’ requirements.
A prop developer may design a product that uses channel 1 to define the brightness of red, channel 2 to define the brightness of green, channel 3 to define the brightness of blue, channel 4 to turn the prop on/off.
The stage lighting designer incorporates these requirements into their control sequences.
Technology: DMX