Adapter using libftdi doesn't work properly on startup (PI4, Buster)

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debaldinger
Posts: 1
Joined: Mon Aug 27, 2018 3:21 pm
Real Name: Carsten Schmid

Hi,

i have a strange problem with QLC 4.12.3 on a PI4 using Buster.
I have set up the PI to autostart QLC with a project, which works fine.

What i encounter is:
After startup, the fixtures flicker when engaged. Looking what could cause this brought up the following:
The USB2DMX Adapter seems to be not used correctly by the Enttec plugin, in dmesg i can see entries like:
[ 82.033491] usb 1-1.4: usbfs: process 682 (EnttecDMXUSBOpe) did not claim interface 0 before use
[ 82.067502] usb 1-1.4: usbfs: process 682 (EnttecDMXUSBOpe) did not claim interface 0 before use
[ 82.100998] usb 1-1.4: usbfs: process 682 (EnttecDMXUSBOpe) did not claim interface 0 before use
[ 82.134633] usb 1-1.4: usbfs: process 682 (EnttecDMXUSBOpe) did not claim interface 0 before use
[ 82.168639] usb 1-1.4: usbfs: process 682 (EnttecDMXUSBOpe) did not claim interface 0 before use

Having QLC+ set to "Hotplug enabled", i now unplug the USB2DMX from the PI and plug it back:
[ 82.236647] usb 1-1.4: usbfs: process 682 (EnttecDMXUSBOpe) did not claim interface 0 before use
[ 82.325387] usb 1-1.4: USB disconnect, device number 3
[ 86.253621] usb 1-1.4: new full-speed USB device number 4 using xhci_hcd
[ 86.400716] usb 1-1.4: New USB device found, idVendor=0403, idProduct=6001, bcdDevice= 6.00
[ 86.400736] usb 1-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 86.400752] usb 1-1.4: Product: JMS USB2DMX OPTO V1.0
[ 86.400767] usb 1-1.4: Manufacturer: JMS
[ 86.400782] usb 1-1.4: SerialNumber: 141500832
[ 86.408202] ftdi_sio 1-1.4:1.0: FTDI USB Serial Device converter detected
[ 86.408360] usb 1-1.4: Detected FT232RL
[ 86.415482] usb 1-1.4: FTDI USB Serial Device converter now attached to ttyUSB0
[ 86.496769] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0

After this, all fixtures work like expected.

I want to install that Raspberry in a location where a power outage should not cause any problems, but with that behaviour of QLC+ i definitely have a problem.
Any idea? Besides using a "USB interruption relay"?

Best regards
Carsten
Sp4rKy
Posts: 46
Joined: Fri Oct 12, 2018 6:36 am
Real Name:

It looks like i have more or less the same issue as you.

Just bought RPi build a few days ago. I use an USB adapter which requires 'DMX USB' output to be configured with "Pro MK2" type.
I started qlcplus through ssh, configured it correctly, saved. But still, when service starts, it does not work.

I did some more checks. If i starts it by hand with the following command line :

Code: Select all

qlcplus -platform eglfs --nowm --web --web-auth --operate --overscan -d 3 --open autostart.qxw
Using pi user (with a copy of /root/.qlcplus/autostart.qxw in pi user's home) everything works correctly and i get no error.
If i use the very same cmdline as root, everything starts, but my adapter keeps blinking red and nothing works.

I triple checked the qfx files, both have same checksum.

The input output map looks like :

Code: Select all

 <InputOutputMap>
   <Universe Name="Universe 1" ID="0">
    <Input Plugin="ArtNet" Line="1"/>
    <Output Plugin="DMX USB" Line="0">
     <PluginParameters UniverseChannels="147"/>
    </Output>
   </Universe>
   <Universe Name="Universe 2" ID="1"/>
   <Universe Name="Universe 3" ID="2"/>
   <Universe Name="Universe 4" ID="3"/>
  </InputOutputMap>
I could run it as the pi user instead of root, but ... would prefer to understand what's wrong there
RudiMent
Posts: 1
Joined: Sat May 22, 2021 8:03 pm
Real Name: Rüdiger Haack

Same problem here :o :shock:
Sp4rKy
Posts: 46
Joined: Fri Oct 12, 2018 6:36 am
Real Name:

So, i finally strace'd both execution as root and pi user. Diff between both gave me some possible reason.
qlcplus open a config file inside ~/.config/qlcplus/Q\ Light\ Controller\ Plus.conf
diffing both, it appears than the one inside /home/pi has a `dmxusbconfig` that the one in root doesn't have.

It may explain why I have different behaviour even with the same project file.

I need to try to copy the conf file from pi to root and see what happens
Sp4rKy
Posts: 46
Joined: Fri Oct 12, 2018 6:36 am
Real Name:

That was it ! I copied the conf file from pi user to root, and everything now works as expected. Not sure why this bug, is the conf file for root provided with rpi image and not updated ?
Anyway, now works for me right after a reboot !
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GGGss
Posts: 2732
Joined: Mon Sep 12, 2016 7:15 pm
Location: Belgium
Real Name: Fredje Gallon

Thanks for reporting...
There are quite some posts here 'complaining' about pi-user and root-user issues.
Your explanation will help others 4 sure.
All electric machines work on smoke... when the smoke escapes... they don't work anymore
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