DMX on op-z (dmx.json question)

Hey to all,

I am trying to get my dmx lights to work on my op-1…
I got the necessary usb interface (Enttec), a dmx fixture, cables,etc,…
What you need to edit is the file called dmx.json on your op-z
That is where trouble comes in …
I am quite new to editing json files,
To be honest I am also new to dmx but I have a technical background and I really want this to work

It is very hard to find any documentation on this(besides the very standard doc found in the manual), sorry for this question… my bad
If anyone else knows more about editing the dmx.json file please feel free to share or discuss…

Or if someone who got this to work on their op-z please if you would be so kind to send me your dmx.json file for my inspiration or point me in the right direction, that would be such a big help

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You an edit a .json file with a text editor. Lots of documentation on DMX is available. https://en.wikipedia.org/wiki/DMX512 is a good starting point.

what light fixture do you have?

Thanks for your reply! Very kind …
American DJ Ultra Hex Bar 6
Tip is very interesting, in the next comment I can send you copy paste of my file, any idea what could be wrong.

{
“profiles”:
[
{
“name”: “rgb”, “1, 2, 3”: [“red”, “green”, “blue”]
},
{
“name”: “dimmer”, “7”: [“intensity”]
},
{
“name”: “movinghead_example”, “channels”: [“knob5”, “knob6”, “knob7”, “knob8”, “red”, “green”, “blue”, “white”, “strobe”]
}
],

"config":
[
	{ "fixture": 1, "profile": "rgb" },
	{ "fixture": 2, "profile": "rgb" },
	{ "fixture": 3, "profile": "rgb" },
	{ "fixture": 4, "profile": "rgb" },
	{ "fixture": 5, "profile": "rgb" },
	{ "fixture": 6, "profile": "rgb" },
	{ "fixture": 7, "profile": "rgb" },
	{ "fixture": 8, "profile": "rgb" },
	{ "fixture": 9, "profile": "rgb" },
	{ "fixture": 10, "profile": "rgb" },
	{ "fixture": 11, "profile": "rgb" },
	{ "fixture": 12, "profile": "rgb" },
	{ "fixture": 13, "profile": "rgb" },
	{ "fixture": 14, "profile": "rgb" },
	{ "fixture": 15, "profile": "rgb" },
	{ "fixture": 16, "profile": "rgb" }
]

}
This is my current dmx.json file, you have any idea what could be wrong… I suppose a lot :slight_smile:
Thanks in advance kingof9x

woa, I’m having the same problem… but I think I’m a bit more lost thant you!

i can’t even seem to find the dmx.json file, do you have to create it and place it in the content folder on the OPZ?

do you have to configure the Enttec usb interface somehow?

let’s get this working! :smiley:

Dmx.json file is on your opz when you connect it with the usb cable it comes with to yr computer. Hold track and turn on yr power than in the config folder you will find the json file… (edit with tekst editor and save and eject yr opz and thats it! And now back to you ;-))

Hi guyken1,

Assuming you have no problems with your dmx/usb interface and fixtures themselves, for the .json file what you need to do is to match the channel type to the DMX channel type for your fixtures:

For example, if your fixture that you want to name “RGBdimmer” has a 4-channel mode that you want to control with the following setup:
Starting with DMX channel 1: Ch. 1: red, Ch. 2: green, Ch. 3: blue, Ch. 4: master dimmer

In the profiles section of the .json file you would then need to add the following line:

{
“name”: “RBGdimmer”, “channels”: [“red”, “green”, “blue”, “intensity”]
},

and then in the config section of the .json file you would then assign fixture 1 to your “RBGdimmer” fixture:

{ “fixture”: 1, “profile”: “RBGdimmer” },

I haven’t extensively tested it yet, but it seems that if you use multiple fixtures with different DMX channel settings you will need to set the fixtures to the appropriate DMX address. For example, if you you added a second RBGdimmer under fixture 2, you should it so that it receives starting on DMX channel 5.

The OP-Z will reject the .json file if it is formatted incorrectly and put it into a separate folder, so after editing the file I found it useful to check whether the file updated correctly before connecting it to the USB DMX interface to test settings.

Hope that helps!

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A big thank you for your kind reply! I ll test it out now

@jflee Could you be so kind to send me your dmx.json file or paste the contents here, just for my inspiration

It really depends on what your fixture’s DMX channel settings are and what you want it to correspond to in the OP-Z light track. My test setup uses fixtures that don’t have a dimmable red/green/blue channel, so it probably won’t be a good reference point. Looking at the manual for the American DJ Ultra Hex Bar 6, if you wanted to use the 7 channel mode you could use the following as an example:

Insert into the “profiles” section (make sure there is a comma separating entries):
{
“name”: “UltraHexBar6”, “channels”: [“red”, “green”, “blue”, “white”, “knob5”, “knob6”, “intensity”]
},

Assuming you want to start on DMX channel 1 on your fixture, edit the first line (“fixture”: 1) and replace “rgb” with the custom profile name:

{“fixture”: 1, “profile”: “UltraHexBar6” },

On the OP-Z there’s no channel type that directly corresponds to “amber” or “uv”, so in the above example I just assigned it to knobs 5 and 6 (accessed with the shift/arrow-up button, knob LEDs will then turn yellow-ish) so that you can check how they work.

After that you can just experiment and see what control layout on the OP-Z works for you. For example, you could set up different profiles and config arrangements for the different channel modes for the hex bar.

One thing that was confusing at first was understanding how “fixture preview” and “step view” worked, you’ll need experiment to see how the patterns/effects and step view parameter locks work with your setup.

@jflee I can’t thank you enough mate for your help!
It is so clear to me now and so logical thanks to your perfect explanation, thanks for being so patiënt with me!
Unfortunately it doesn’t work yet, as you said in your first comment, it is probably my interface, it is an Enttec open usb widget(the cheapest there is:-)) but not the Enttec dmxusb pro… I ordered this one last night, I ll update you when it arrives…Can’t wait to try it out
I guess there is no option with the cheaper Enttec stuff :frowning:

Thank you again because before your helpful comment, my understanding with this Json files was almost zero !

ps:indeed the preview(step & fixture)was hard to get yr head around , now with the + and - button it is easy to see yr result, what a complex device this is(and I mean it in a good way)

Got it working with the enttec dmxusb pro, allthough I need a powered usb hub to make it work, but I was able to mix colour and so on…
Only problem when I start a sequence and the lights are connected after a few bars the playback slows down extremely, maybe the hub is not compatible ?
Please feel free to join the discussion

What USB hub are you using? TE lists the “kingston nucleum” as the only supported usb hub. If you are using that and still seeing the pattern slow down you should contact TE for support. If you are using a different hub I bet they would advise you to get the supported hub.

Just curious, if you op-z is fully charged can it run the enttec dmxusb pro? according to the manual that should work, but will drain your battery quickly. If it doesn’t work at all I would contact TE support since it says you can do that specifically in the manual.

@guyken1 Glad you are getting it working :slight_smile: I am using a Kingston Nucleum for a USB hub with the entice dmxusb pro, and I can confirm weird tempo slowdowns every once in a while. It seems to happen when changing projects, but I haven’t tested it enough to find a consistent reason…

@jflee tempo slowdowns with nucleum like…occasionaly…every once in a while…? as in once every hour or every few hours or could you be a little bit more specific? Thanks in advance!

@kingof9x said:
What USB hub are you using? TE lists the “kingston nucleum” as the only supported usb hub. If you are using that and still seeing the pattern slow down you should contact TE for support. If you are using a different hub I bet they would advise you to get the supported hub.

Just curious, if you op-z is fully charged can it run the enttec dmxusb pro? according to the manual that should work, but will drain your battery quickly. If it doesn’t work at all I would contact TE support since it says you can do that specifically in the manual.

@kingof9x Thanks for your reply , here is my reply to your questions:
sitecom usb hub 2.0 , and no I fully charged my op-z and it does not work (my dmx fixture blinks for 1 second and thats all it does) without the hub,
although with the Sitecom usb-hub it works but it is also not very stable when I press play on the op-z(major slowdown)

@gyken1 and @jflee you two are champions. Thanks for investing in the hardware and for your time. If you have not already, I am sure TE support would like to get this info from you with your system logs. It sounds like there may be some bugs in the DMX implementation that are not being noticed by the majority of the community. Since the manual says you can connect the light directly without a USB hub and that doesn’t work I would contact support with as much info as possible.

Thanks for experimenting with this stuff for us!

@guyken1 I haven’t had problems with tempo when I’m working on a pattern within a project, but when switching projects during playback it seems as though the project tempo gets reset to a much slower tempo that doesn’t change until I turn the op-z off and on. With playback stopped I can switch projects without problem. I haven’t done extensive troubleshooting to figure out all the variables though…

Also ordered A kingston Nucleum hub…
Does not work as I expected though…
Similar behaviour as with my other usb hub, as long as I m not pressing play on the op-z, it is working fine!I can mix colours, change speed and dimmer values…
But once I press play on the op-z , it’s a matter of a few seconds or max 2 minutes before it slows down and becomes unresponsive !(even without changing patterns or project)
I send an email to TE(because now I have all the hardware at my disposal that they have guaranteed that should work) with my dmx.json file and log, see what they say about it…
Maybe a mistake in my config json files or ? A little bug?
Really hope there is a way to make it more stable and usable, if anyone here wants to throw in some possible solutions/questions/tips/tricks … Always welcome

Fantastic … after resetting my op-z, everything works perfect now, even directly in the op-z without a usb hub!
Really happy that it all works by the book now
And the strange thing is : with the default dmx.json file , I did not change a thing about it ;-)))
thanks to everyone to help me

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