Newsgroups: rec.arts.theatre.stagecraft
Subject: Re: Building DMX stuff from scratch
References:  <[email protected]>
"Richard Crowley"  writes:

> "Torrance Bell" wrote ...
> > Been toying with the idea of putting together a box that takes a dmx
> > signal and controls some relays.  so far, I have found one chip that
> > meets my needs perfectly.  The Artistic Licence AL4008.
> > This is something I would like to use in the future for doing Xmas
> > lights like the infamous trans siberian orchestra video recently
> > floated around the net.
> 
> That light show was implemented using products from
> http://www.lightorama.com  They appear to use a
> proprietary(?) communication bus called "SC485"
> which appears to be significantly less expensive than
> DMX.

I am just wondering why would using rom proprietary 
RS-485 bus (I quess that "SC485" is RS-485 based) 
would be in any way significantly less expensive than
DMX. There is nothing magic in DMX-512 compared to other 
RS-485 busses that woudl make is more expnsive. 
All you need to make DMX-512 interface (transmitter or receiver) 
is a decent microcontroller (6-10 Euros/dollars) and RS-485 
transceiver IC (maybe 1-2 Euros/dollars). 

> The European magazine "Elektor Electronics" (published
> in several languages including English) has published
> several DMX construction articles and generally has pre-
> programmed chips and PC boards available for sale...
> http://www.elektor-electronics.co.uk/default.aspx?tabid=48&q=DMX

There are also many interresting DMX-512 project in different 
web sites. The best ones I know are listed at
http://www.epanorama.net/links/lights.html#dmx512
Look "DMX-512 circuits" section. 


-- 
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/