What is DMX512?
In the good old days in the stage lighting is a number of manual potentiometers, which were controlled lights during the performance. They were located next to the stage, and electricity supplied by them to the lamps on the long power cable that runs around the whole scene. Not that these cables were too much, just the whole system was obtained by a cumbersome and awkward. You were like an octopus, which ruled this huge and lined up the light scenes.
All this went on for as long as some craftsmen may have guessed provide rotary engines ... and op! Behind the scenes appeared a small, elegant bar, potentiometers and motors were removed at the base of the stage and everything! Only a small number of thin wires connect the console now with the engines. However, the problem remained - the speed, or rather its absence (as we now would seem). The engines have a limited speed, and it affects the whole installation as a whole.
Soon came the first electronic dimmers and the first console. Necessity - the mother of invention, and soon began to acquire more console familiar to us form. Office produced with a low DC voltage, depending on which varied luminous flux. The voltage was applied on separate wires for each channel, and must say that on such systems sometimes work today.
We used different voltage and polarity, but the system +10 V was the most popular. However, she suffered from the following drawbacks:
- prone to noise and the formation of ground loops, if skommutirovanna wrong.
- nonlinear worked with different types of lamps.
Offers various solutions to these problems, but they all proved unsatisfactory.
Then came the first computerized console with simply being able to save a scene in memory. Outputs were still analog, and all improvements related to the transfer of different signals on one wire.
Computers have opened a new dimension to the whole system: fader should not be responsible for a specific dimmer - it can be assigned to any group of dimmers or dimmer. With faders and buttons on one end and dimmers on the other computer could establish any link between the program, the actions of the operator and light.
Various manufacturers entered the market with all kinds of advanced control panels. They quickly realized that digital data exchange system between the console and dimmers has become a natural complement to the computer system data, as well as one and the other had as an output signal "number". It was developed by a number of different protocols, and disappeared as a result of the interchangeability between devices from different manufacturers, and the whole set had to buy from one manufacturer. Most suffered from end-user, and create a single standard interface under the circumstances was a must.
U.S. Institute of Theater Technology (USITT) first in 1986, developed as a protocol DMX512 standard interface for exchanging data between dimmers and consoles.
It was a fairly simple idea, which could easily be applied and further developed by those who have an interest.
In 1990, the first standard was minor corrections and fixes some bugs, and now known as the standard USITT DMX512 (1990). It all started with a protocol for controlling dimmers, but ended that with this protocol are controlled digital lighting, kolorchendzhery, Lira, strobes, smoke machines, lasers, fountains, stage machinery, and even confetti spreaders.
Oksid.ch - All about DMX 512
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Terminators and their installation