High End Systems AXON - Manual (Page 37)

Axon Media Server User Manual 17
Chapter 4:
DMX Programming Basics and Quick Start
If you are new to DMX programing, this chapter will give you a brief overview
on programming DL.3, DL.2, and Axon media servers followed by a example of
using a Wholehog console to patch and display output from a media server.
DMX Programming Overview
DMX512 Links
A lighting console typically utilizes a protocol called DMX512 to communicate with automated
lighting fixtures and conventional dimmers. This protocol consists of 512 unique channels of
control per output link (universe). Typically a lighting fixture or device will use a channel for
each parameter’s function. Each channel consists of 256 values ranging from 0 to 255. The
lighting console is programmed to transmit a corresponding DMX value for the desired function
of each parameter. All DMX values are stored within in the lighting console, and typically are
referred to as cues, scenes, or presets. A lighting console locates a device on the link by it’s
DMX Start Channel.
8-bit vs. 16-bit DMX Parameters
Most parameters of an automated light use one channel of DMX providing 256 values of control
(0-255). This is known as 8-bit DMX. Although most parameters use 8-bit DMX, several require
a more accurate range of values than can be provided with a single DMX channel.
By utilizing two DMX channels for a single parameter, 65535 values become available for
controlling and adjusting parameter functions. This is known as 16-bit DMX. You can adjust
16-bit DMX values in both coarse and fine increments. The first channel of the pair provides
coarse control changes of the DMX value in increments of 256. The second channel provides fine
control and changes of the DMX value in increments of 1.
Individual access of the two DMX channels used with 16-bit parameters varies by lighting
console. Most modern DMX consoles bind these two channels into a single 16-bit parameter to
accurately perform 16-bit crossfades. Consult your lighting console manual for further
information.