Here i have added a video to explain my problem:
I think i solved my problems.
Read more here:
https://groups.google.com/forum/#!topic/open-lighting/RY46V46lgTs
Hi all, Iām the OP and wanted to share the solution I seem to be settling on.
Basically I decided not to do DMX in software, but in hardware. Mainly because I was, and still am, completely baffled by why anyone would want to do this in OLA, or get involved with DMX over an IP network. I donāt mean that to sound rude to all the good people who have discussed solutions here! Perhaps itās just my lack of understanding!
My setup:
openHAB sends MQTT messages to an Arduino, which is connected to a DMX shield (mine is the orange one from Tinkerkit, Ā£15, easy to set up). This is connected to my numerous 12 channel DMX lighting dimmers. The good thing is, if I need to change the hardware and use a 0-10V dimmer instead, itās an easy change.
In my Arduino code, I can set dimming curves - itās fun working out the mathematical formulae for dimming curves and trying to code them. (Fun = āsurprisingly difficult to do wellā)
This setup also allows for complete independence from network switches / servers etcā¦ In the case of IT problems, we donāt want to lose all our lights! For example I plan to make a basic emergency backup panel with a number of buttons, each one will set a lighting zone on or off (or probably 75% dimmed). This would be a PCB directly connected to the Arduino with the DMX shield. Alternatively I might make 3 or 4 emergency panels hidden in cupboards around the house, connected to the central Arduino with RS485 or something.
I was tempted to use RS485 directly from all my automation control panels as the primary mode of communication, rather than MQTT. Then have a central receiving Arduino that controls DMX, updates openHAB, and receives messages from openHAB as well. But there are just too many benefits of going full-fat MQTT with the wall panels, such as directly addressing e.g. computers.
Still some architectural choices to make, but those are my latest thoughts!
Hey hazymat,
Do you mind if I pick your brain a bit on your current raspberry pi / arduino / mqtt configuration. Think I am leaning this way as well and would love to copy a it of what you have done to save time and sanity 
Hey @Matthew_Mathis - sure go ahead. I was going to give you my email, but on second thoughts might be useful to others if we discuss on this forum (maybe even a new thread?)
By the way, my home construction project has taken approximately 3 years longer than I thought, so I havenāt actually implemented everything yet in the home, but Iāve done a fair bit of testing so far, enough that I know the only thing between me and home lighting success is my own time / work!
look this link
Working good!