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ArtNet Input AND Output possibly not working
Posted: Mon Jan 04, 2016 8:47 pm
by siegmund
Hey guys,
I ran into an issue where I'm not sure if the problem is me or the software...
Sorry for a longer text describing my setup:
I got two ArtNet Nodes. One is for input, the other for output. for testing purposes, between them there is a LED Spot.
Then I have two computers running QLC+ (both Xubuntu 14.04 64Bit with QLC+ 4.10.2, Qt5.2.1). The first (Laptop) outputs signal to the output-node (ArtNet universe 1). That works easily. The other computer (desktop) receives data from the input-node. This isn't that problem either.
It gets complicated when I try to send some output from the desktop, too. As soon as I check the box for "output" in the In/Out-Tab (even if I use another universe for output than for input) I'm no longer able to receive ArtNet data from the input-node (sent by the laptop).
Maybe some of you will ask: "Why this?"
- The laptop simulates a DMX controller. Some time I want to be able to control my programmed show with such a DMX controller and so I need exactly that setup.
The fact that only checking the output makes the difference got me thinking that the problem might be inside QLC+.
What do you guys say? Maybe somebody could tell me something about how ArtNet data is sent in QLC+?
Update: While writing this I did some tests with wireshark. At first I thought the ArtNet data ist transmitted directly from one PC to another, because all 10 seconds there is some TCP traffic going on between the two instances, but this doesn't increases when changing values on the laptop. So the input on the desktop really comes from the interface.
I hope this is clear enough. If not, don't hesitate to ask.
Thanks for help!
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 7:45 am
by plugz
Hello,
This might be the same issue as this one:
http://qlcplus.org/forum/viewtopic.php?f=5&t=8951
The issue is probably fixed with the current source code.
Can you compile QLC+ yourself to test a new version of the ArtNet plugin ? If not, can you download a TEST version ?
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 7:45 am
by siegmund
Hi plugz!
Thanks for your reply.
plugz wrote:This might be the same issue as this one:
http://qlcplus.org/forum/viewtopic.php?f=5&t=8951
The issue is probably fixed with the current source code.
Can you compile QLC+ yourself to test a new version of the ArtNet plugin ? If not, can you download a TEST version ?
I read that some time ago but didn't realize that this is a very similar setup to mine. I'll give it a try today.
Installing the latest automated git build for Ubuntu should do that, right?
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 12:42 pm
by plugz
The latest automated git build (4.10.3.20151231.adf825e) does contain the wanted changes.
It should work
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 3:30 pm
by siegmund
plugz wrote:The latest automated git build (4.10.3.20151231.adf825e) does contain the wanted changes.
It should work
I'm really sorry but this version does not work at all
Output works. But apparently no input is received (no joystick) even with no output selected.
Do you have some ideas to debug that?
I definitely can confirm that it's the other version - I tested it with the 4.10.2 release before I switched to the git automated build and that caused QLC+ to not recognize the input..
Besides, I really really like the ability to chose the ArtNet universe for input!
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 3:44 pm
by siegmund
While playing around I noticed a smaller bug: It's not possible to set the input ArtNet universe back to 0 if it was changed.
By the way: Could somebody please state why the upper limit for the ArtNet universe number is 65535?
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 5:19 pm
by plugz
For the input not working:
Are ArtNet universes the same ?
Do you send ArtNet to a broadcast address or to the IP of the target computer ? What's the network configuration like ?
siegmund wrote:While playing around I noticed a smaller bug: It's not possible to set the input ArtNet universe back to 0 if it was changed.
I will look into it, thanks
siegmund wrote:By the way: Could somebody please state why the upper limit for the ArtNet universe number is 65535?
I believe it's defined like this by the ArtNet protocol
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 5:19 pm
by siegmund
At first, thank you for your help!
plugz wrote:For the input not working:
Are ArtNet universes the same ?
Yes. QLC+ assumes in 4.10.2 the ArtNet universe 0, doesn't it?
plugz wrote:Do you send ArtNet to a broadcast address or to the IP of the target computer ? What's the network configuration like ?
When outputting ArtNet from the computers I use the addresses of the interfaces. Since the interfaces do not support setting a target IP they broadcast the ArtNet messages.
Just as I already stated, I made no change instead of the new QLC+ version.
A test with wireshark also shows that the packets are arriving at my network card.
Is there a possibility to get a little deeper to see whats going on?
plugz wrote:
siegmund wrote:By the way: Could somebody please state why the upper limit for the ArtNet universe number is 65535?
I believe it's defined like this by the ArtNet protocol
Maybe there should have someone a look into again. Following the ArtNet-specs from
http://www.artisticlicence.com/WebSiteM ... rt-net.pdf we can only have 32,768 universes, because the bit 15 seems to be always 0. [sorry for hijacking the thread in this way - should I open another one for that?]
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 8:30 pm
by plugz
siegmund wrote:At first, thank you for your help!
I made the changes to the ArtNet plugin, so thanks for testing them
siegmund wrote:plugz wrote:For the input not working:
Are ArtNet universes the same ?
Yes. QLC+ assumes in 4.10.2 the ArtNet universe 0, doesn't it?
It should stay the same, yes.
siegmund wrote:plugz wrote:Do you send ArtNet to a broadcast address or to the IP of the target computer ? What's the network configuration like ?
When outputting ArtNet from the computers I use the addresses of the interfaces. Since the interfaces do not support setting a target IP they broadcast the ArtNet messages.
Just as I already stated, I made no change instead of the new QLC+ version.
A test with wireshark also shows that the packets are arriving at my network card.
I'm not sure I understand. The network interface of the target computer does not have an IP address ? Or the computer that sends ArtNet ? Or the ArtNet nodes ?
siegmund wrote:Is there a possibility to get a little deeper to see whats going on?
Can you draw me a network topology ?
Or screenshots of the ArtNet configurations for both computers, and ifconfig results ? I suspect a network mask different than /24.
siegmund wrote:plugz wrote:
siegmund wrote:By the way: Could somebody please state why the upper limit for the ArtNet universe number is 65535?
I believe it's defined like this by the ArtNet protocol
Maybe there should have someone a look into again. Following the ArtNet-specs from
http://www.artisticlicence.com/WebSiteM ... rt-net.pdf we can only have 32,768 universes, because the bit 15 seems to be always 0. [sorry for hijacking the thread in this way - should I open another one for that?
You're right, I'll take care of this.
plugz wrote:siegmund wrote:While playing around I noticed a smaller bug: It's not possible to set the input ArtNet universe back to 0 if it was changed.
I will look into it, thanks
This was already the case with output ArtNet universe in 4.10.2, I'll fix this too
Re: ArtNet Input AND Output possibly not working
Posted: Tue Jan 05, 2016 8:30 pm
by siegmund
plugz wrote:siegmund wrote:At first, thank you for your help!
I made the changes to the ArtNet plugin, so thanks for testing them
It's a pleasure
plugz wrote:
siegmund wrote:plugz wrote:Do you send ArtNet to a broadcast address or to the IP of the target computer ? What's the network configuration like ?
When outputting ArtNet from the computers I use the addresses of the interfaces. Since the interfaces do not support setting a target IP they broadcast the ArtNet messages.
Just as I already stated, I made no change instead of the new QLC+ version.
A test with wireshark also shows that the packets are arriving at my network card.
I'm not sure I understand. The network interface of the target computer does not have an IP address ? Or the computer that sends ArtNet ? Or the ArtNet nodes ?
Sorry this wasn't clear enough. With "interfaces" I normally mean the DMX interfaces.
Everybody has an IP address, of course (; The DMX interfaces got static ones, the Computers via DHCP (but they're not changing). The computers send their ArtNet output to the IP addresses of the DMX-interfaces. The DMX-interfaces seem not to be able to send ArtNet to an IP address, so I assume they are broadcasting.
siegmund wrote:Is there a possibility to get a little deeper to see whats going on?
Can you draw me a network topology ?
Of course, find that attached (;
plugz wrote:I suspect a network mask different than /24.
If I didn't miss something you're (unfortunately) wrong...
plugz wrote:plugz wrote:siegmund wrote:While playing around I noticed a smaller bug: It's not possible to set the input ArtNet universe back to 0 if it was changed.
I will look into it, thanks
This was already the case with output ArtNet universe in 4.10.2, I'll fix this too
This was the next thing I wanted to check
ifconfig output
Desktop
Code: Select all
eth1 Link encap:Ethernet Hardware Adresse 74:d4:35:fd:43:9d
inet Adresse:192.168.2.21 Bcast:192.168.2.255 Maske:255.255.255.0
inet6-Adresse: fe80::76d4:35ff:fefd:439d/64 Gültigkeitsbereich:Verbindung
UP BROADCAST RUNNING MULTICAST MTU:1500 Metrik:1
RX-Pakete:160995 Fehler:0 Verloren:0 Überläufe:0 Fenster:0
TX-Pakete:135503 Fehler:0 Verloren:0 Überläufe:0 Träger:0
Kollisionen:0 Sendewarteschlangenlänge:1000
RX-Bytes:199382820 (199.3 MB) TX-Bytes:16828416 (16.8 MB)
Interrupt:20 Speicher:f7c00000-f7c20000
Laptop
Code: Select all
wlan0 Link encap:Ethernet Hardware Adresse ac:72:89:2d:4a:38
inet Adresse:192.168.2.25 Bcast:192.168.2.255 Maske:255.255.255.0
inet6-Adresse: fe80::ae72:89ff:fe2d:4a38/64 Gültigkeitsbereich:Verbind
Edit: Attached some screenshots.
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 7:22 am
by plugz
OK thanks for all the information
So now, the question is: the "DMX IN" interface is sending ArtNet DMX packets to what broadcast address ? 192.168.2.255, or something else ? You should be able to see this on wireshark.
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 7:22 am
by siegmund
plugz wrote:So now, the question is: the "DMX IN" interface is sending ArtNet DMX packets to what broadcast address ? 192.168.2.255, or something else ? You should be able to see this on wireshark.
I did never think about it, but it broadcasts to 255.255.255.255 - is that good or bad?
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 9:53 am
by plugz
ArtNet PDF, page 7: "Limited Broadcast: Art-Net packets should not be broadcast to the Limited Broadcast address of 255.255.255.255."
It should broadcast to the subnet's broadcast address: 192.168.2.255.
If you can't change that, then I'll have to do some new changes to the ArtNet plugin.
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 9:53 am
by siegmund
plugz wrote:ArtNet PDF, page 7: "Limited Broadcast: Art-Net packets should not be broadcast to the Limited Broadcast address of 255.255.255.255."
It should broadcast to the subnet's broadcast address: 192.168.2.255.
I also just read that. The 4.10.2 release also listens to the limited broadcast, right?
Give me a minute for checking that, but as I remember I'm not able to change the broadcast. But from the IP and net mask the interface should be able to build this subnet broadcast message, shouldn't it?
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 9:53 am
by siegmund
plugz wrote:If you can't change that, then I'll have to do some new changes to the ArtNet plugin.
I'm really sorry for holding you busy. Seems that the programmer doesn't really take care of the ArtNet specs:
Code: Select all
// send an ArtDmx packet
void artnet_sendDmxPacket(void) {
[...]
create_new_udp_packet(sizeof(struct artnet_dmx) + artnet_dmxChannels, artnet_port, artnet_port, (unsigned long)0xffffffff);
}
I already wrote him an email.
The question is: Is that a single case or are there more of these not well programmed interfaces?
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 10:30 am
by plugz
OK then I'll make sure to make this work again, thank you. Should be done in a few days.
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 10:30 am
by siegmund
plugz wrote:OK then I'll make sure to make this work again, thank you. Should be done in a few days.
As I said, there is the possibility that this is only a single case.
The funny thing is, that the broadcast address in the DMX interface SourceCode is calculated twice, but never used. So I assume there was something forgotten. I hope he fixes that with a new firmware.
But anyway - thanks for your quick and constructive help
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 1:27 pm
by plugz
Actually it's done already
Universe on 15bits: done
Unable to restore parameters back to default: fixed
Able to receive broadcasts on 255.255.255.255: done
Are you able to compile QLC+ from sources ?
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 1:27 pm
by siegmund
plugz wrote:Actually it's done already
Universe on 15bits: done
Unable to restore parameters back to default: fixed
Able to receive broadcasts on 255.255.255.255: done
Sounds great! Especially because the guy who sold the interface really is the most ignorant person that has ever answered a mail from me.
plugz wrote:Are you able to compile QLC+ from sources ?
Yes.
Re: ArtNet Input AND Output possibly not working
Posted: Wed Jan 06, 2016 2:07 pm
by plugz
siegmund wrote:plugz wrote:Are you able to compile QLC+ from sources ?
Yes.
If you want to test it, the code is available on the master branch