May 17, 2013, 8:01am
Hi ArtNet users, Devs,
When I send DMX values over ArtNet with
DMX (Network Artnet Sender) , I can only send full universes. Is there a way of sending only active channels on a universe, not the full frame? Ideally with a spreadable DoSend Input of the DMX ArtNet node. Does anybody know about a specification regarding this? Does ArtNet allow to send only some values?
ArtNet is DMX “multiplexed” and the DMX protocol is sending the all 512 channels in each packet. I think it’s not possible to send only a few channels.
May 17, 2013, 10:04am
Thanks for that confirmation!
After my post here I figured from the ArtNet standards definition that the ArtDMX function always sends DMX512 data, which is essentially one full DMX universe.
This poses questions how to use one universe with two ArtNet nodes without overwriting values …
Can I address fixtures from two machines on different channels in the same universe without creating overwrites?
May 17, 2013, 12:20pm
Can’t you change the universe on one artnet node?
May 17, 2013, 12:23pm
Yes, but with a temproal difference I want to control the same fixtures from different machines. Or rather: Sometimes I want to control some fixtures from a specific machine, while usually they are controlled by a regular light desk.
If I understand well your goal, I think there are two cases:
only one machine > only one artnet node by dmx universe, you do normal slice operations to mix your values before the artnet node.
two or more machines > If you want to “merge” values, I think you need to chain your machines.
machine1 >>> machine2 ( receives universe and modifies it ) >>> artnet receiver
May 17, 2013, 12:51pm
May 17, 2013, 12:53pm
or you could use a device like the Datagate from Enttec:
EDIT: this will give you an artnet to dmx box as well as a merger (it seems, I have not tried it)
May 17, 2013, 1:03pm
(at least some) artnet-nodes support merging with ltp (latest takes precedent)
that might be what you want.
// ah, almost the same answer as sune
May 17, 2013, 8:56pm
Thank a lot for this helpful information!
I’m pretty sure that PixelMad, an osx LED mapping app only sends channels that have changed, and as a result can handle 100’s of universes of channels, a spreaded send would be really useful!
After playing a bit with Artnet in vvvv, I find merging values in vvvv is great because you can use all animation nodes where “classic” mergers allow only HTP/LTP.