Jump to content
Light-O-Rama Forums

DMX pinouts Vary for LOR?


Recommended Posts

do the DMX pinouts vary from controller to controller?


I run my whole show in DMX using CCB's and PC-controllers and all of them work flawlessly..


however I tried to wire up my RGB floods and the controller that came with them (CMB24D)  and I get nothng but a flashing LED on the board.


if I jumper back to LOR network I can talk to it via LOR..  I move the jumpers to the DMX position and connect it up to a known good DMX connection and flashing light..


some of the docs I read are confusing but seem like its Pinout is different in DMX from other controllers?


can anyone confirm?



Link to comment
Share on other sites

As I understand it from reading that section of the manual, and what I already knew, the DMX / LOR jumpers on the CMB24D control the physical pinout on the RJ-45 connectors.  Remember that the DMX standard (when using an RJ-45 connector) is to use pins 1 & 2, whereas the LOR standard is to use pins 4 & 5.  In both cases the data is sent via the same RS-485 electrical standard.  On most LOR controllers, in either case, pins 4 & 5 are used resulting in the need for a "crossover" cable between LOR controllers operating in DMX and normal DMX controllers or dongles.  I am assuming that the jumpers were provided to allow the CMB24D to operate on either pinout standard just by moving a few jumpers.


So, if you are getting blinking status light on the CMB24D when attempting to use DMX with the jumpers in the DMX position, but connected to other LOR controllers, the controller is not seeing a signal, so move the jumpers back to the LOR position.


I agree that the docs are not real clear on this setting.

Link to comment
Share on other sites

super!, ill give this a shot..  that makes sense that 4 and 5 were used in the LOR protocol because thats the RJ45 standard for Most RS485 based networks..


I guess because DMX was always based on the LXR connector they stayed with 1 and 2 even in an RJ45..


and yeah im in fact running my DMX signals on 4 and 5 because I am running home-built dongles from my Sandevices controllers in DMX mode...


I didnt realize the jumpers just altered the pinouts I was thinking they set terminations and signal levels  so I never tried putting them back and plugging it in..




Link to comment
Share on other sites

I got this several times on the help desk too.  The problem is that we silkscreened those jumpers as 'LOR/DMX'.  What we should have called them was 'LOR/ESTA'


The LOR pinout on EVERYTHING assumes pin 4 and 5.  It does not matter if you are running DMX protocol or LOR protocol -- data lives on 4 and 5.  


We came up with that standard long before anyone out there in the industry.  Ok, that is giving LOR too much credit.  I really can't even call it a standard because other lighting companies making similar products back then used their own pins, or changed the polarity of the pins.


The 'ESTA',(Entertainment Services and Technology Association, which in 2010 merged with Plasa - "Professional Lighting and Sound Association", which used to be BADEM - the "British Association of Disco Equipment Manufacturers".  REALLY..  Go check it out) finally in 2004 had approved the DMX protocol.  Several years later they agreed on how DMX protocol should be sent on twisted pair.  They picked...  Drum roll....  1 and 2.  Not that it mattered that we were out there already doing DMX 512 on twisted pair on 4 and 5.  Feh! :P


So the world standardized on 1 and 2.  But we have such a large existing user base we can't just switch over to 1 and 2. 


Previously if you wanted to use our equipment in a DMX environment, or wanted to use our Adapter as a DMX adapter, you had to build a special cable.  4 & 5 end up on 1 & 2, or vice versa depending on if you are going from standard DMX equipment to LOR equipment or the other way.  For the limited number of people out there at the time (mostly professionals) this was not a big deal.  They were probably already using XLR cable and not twisted pair, so for them to build a cable that was ESTA XLR DMX on one side to LOR RJ45 DMX on the other was not a big deal.  In fact a quick peek at the LOR website will show a document on how to do just that.


Today however more and more people are using DMX.  DMX has finally gained traction in the world as the defacto standard for theatrical lighting and sound equipment to talk.  What can we do?  We can add jumpers to our boards that will allow for you to change the pinouts there and not worry about building a cable correctly.  No special cables means less headaches.


We decided to designate the 2 positions LOR (good) and DMX (maybe in hindsight not so good).  People see that and think OH!  I want to run this device as part of a DMX universe so I need to move the jumpers.  Hey, I would too!  Problem is they are connecting to other LOR controllers that are also running in DMX mode.  Those controllers are all fat dumb and happy talking on 4 and 5.  Here comes the CMB24 (or whatever) controller where you moved the jumpers.  It wants data on 1 and 2.  Hair pulling starts.


Or even worse....  People already have one of these special 4&5/1&2 cables built.  They use that cable from standard DMX equipment (1 and 2), which then puts the signal back on 4&5, and swap the jumpers - which makes the board want to get data from 1 and 2!


So whenever you see a 'LOR/DMX' jumper, don't think 'LOR or DMX protocol'.  Think 'LOR or ESTA pinout'

Link to comment
Share on other sites

  • The topic was locked
This topic is now closed to further replies.
  • Create New...