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5. APPENDIX
A Quick Lesson On DMX
DMX (aka DMX-512) was created in 1986 by the United States Institute for Theatre Technology (USITT)
as a standardized method for connecting lighting consoles to lighting dimmer modules. It was revised in
1990 and again in 2000 to allow more flexibility. The Entertainment Services and Technology Association
(ESTA) has since assumed control over the DMX512 standard. It has also been approved and recognized
for ANSI standard classification.
DMX provides up to 512 control "channels" per data link. Each of these channels was originally intended
to control lamp dimmer levels. You can think of it as 512 faders on a lighting console, connected to 512
light bulbs. Each slider's position is sent over the data link as an 8-bit number having a value between
0 and 255. The value 0 corresponds to the light bulb being completely off while 255 corresponds to the
light bulb being fully on.
DMX is connected using a daisy-chain configuration where the source connects to the input of the first
device, the output of the first device connects to the input of the next device, and so on. The standard
allows for up to 32 devices on a single DMX link.
Each receiving device typically has a means for setting the "starting channel number" that it will respond
to. For example, if two 6-channel fixtures are used, the first fixture might be set to start at channel 1 so
it would respond to DMX channels 1 through 6, and the next fixture would be set to start at channel 7 so
it would respond to channels 7 through 12.
The greatest strength of the DMX communications protocol is that it is very simple and robust. It in-
volves transmitting a reset condition (indicating the start of a new "packet"), a start code, and up to 512
bytes of data. Data packets are transmitted continuously. As soon as one packet is finished, another can
begin with no delay if desired (usually another follows within 1 ms). If nothing is changing (i.e. no lamp
levels change) the same data will be sent out over and over again. This is a great feature of DMX -- if for
some reason the data is not interpreted the first time around, it will be re-sent shortly.
Not all 512 channels need to be output per packet, and in fact, it is very uncommon to find all 512 used.
The fewer channels are used, the higher the "refresh" rate. It is possible to get DMX refreshes at around
1000 times per second if only 24 channels are being transmitted. If all 512 channels are being transmit-
ted, the refresh rate is around 44 times per second.
Art-net™ Protocol
Art-Net is a protocol for transmitting the lighting control protocol DMX512-A (with RDM) over the User
Datagram Protocol of the Internet Protocol suite. The protocol was developed by Wayne Howell and his
company, Artistic Licence Engineering (UK) Ltd, is open for implementation with attribution but without
charge, and made available as a software development kit for convenience. It is typically implemented
as lighting-control nodes in embedded controllers, driven from a lighting desk or similar software operat-
ing as a server. Art-Net compatible products are made available by dozens of companies.
ArKaos Kling-Net™
ArKaos has designed the Kling-Net protocol to allow the distribution of real-time video data to remote
display devices, such as LEDs or LED panels, over Ethernet.
Many first time users are afraid of using LED lighting because of the complexity of networking and con-
trol issues. Using and networking LED lighting has required a high level of technical knowledge which has
been a deterrent for many.
ArKaos wanted to remove all this complexity and replace it with an easy protocol which automatically
takes care of the magic numbers for the user!
The purpose of Kling-Net is:
• To allow the automatic configuration and connection of display devices to a computer
• To add some 'intelligence' into display devices, which enables auto configuration
• To ensure a perfect time synchronization of multiple display devices
• To avoid using expensive hardware video converters to send video to display devices
• To allow the creation of an heterogenic network of display devices from different manufacturers, which
can all be controlled from one computer
Page 15
Solar Ray™ User Manual Rev. A
© 2015 Blizzard Lighting, LLC
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