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No Screen but Web interface
Posted: Fri Sep 13, 2024 6:17 pm
by vicat56
Hello everyone,
i tried to install using the qlcplus_raspios_bookworm_20240907 image QLC on a Raspberry pi 4 with a 64 gb micro SD (don't have less...)
I have an HDMI monitor plugged in (1080p 144hz monitor, locked here at 60hz)
i tried a VGA monitor (via cheap converter)
i have this error when i look at the status of qlc :
Code: Select all
pi@raspberrypi:~ $ sudo service qlcplus status
● qlcplus.service - Q Light Controller Plus
Loaded: loaded (/lib/systemd/system/qlcplus.service; enabled; preset: enabled)
Active: active (running) since Fri 2024-09-13 19:05:33 BST; 1min 34s ago
Docs: man:qlcplus(1)
Main PID: 548 (bash)
Tasks: 9 (limit: 3917)
CPU: 2.199s
CGroup: /system.slice/qlcplus.service
├─548 bash /usr/sbin/qlcplus-start.sh
└─635 /usr/bin/qlcplus -platform offscreen --nowm --web --web-auth --operate --overscan
We can see that the status is "-platform offscreen", so i believe that the raspberry don't detect the screen, but the soft is working.
if i
, it show up !
What can i do to fix that ?
Thank you !
Re: No Screen but Web interface
Posted: Fri Sep 13, 2024 7:54 pm
by mcallegari
At the beginning of the startup script there is a check for a connected display
https://github.com/mcallegari/qlcplus/b ... art.sh#L22
if that fails QLC+ starts without an actual output.
I'd say your display is slow to be detected (or sleeping?) so you'd need to delay the systemd script to a later stage of the boot sequence (e.g. after network)
Or brutally place a sleep command before the check above.
Re: No Screen but Web interface
Posted: Sat Sep 14, 2024 9:37 am
by vicat56
Hello, thanks for your help, i will try to delay that !
Btw, i think that you are right with the "slow" monitor thnig, because i tried this morning and i needed to start the screen a few second before the raspi to change manualy the video input, and now it works....! I dig a bit further
thank you again
Re: No Screen but Web interface
Posted: Sun Sep 15, 2024 5:28 am
by markzvo
I have seen this behavior as well, some boots do not work properly because the display is not yet detected... I will probably have to add sleep 3 to /usr/sbin/qlcplus-start.sh file before the HDMI detection logic
Re: No Screen but Web interface
Posted: Mon Sep 23, 2024 9:44 am
by vicat56
great idea !
thank you
Re: No Screen but Web interface
Posted: Wed Oct 16, 2024 8:50 pm
by Peetem
markzvo wrote: ↑Sun Sep 15, 2024 5:28 am
I have seen this behavior as well, some boots do not work properly because the display is not yet detected... I will probably have to add
sleep 3 to
/usr/sbin/qlcplus-start.sh file before the HDMI detection logic
Did this work? How was it done?
Still can't get mine to recognize the display....
Re: No Screen but Web interface
Posted: Mon Oct 21, 2024 1:39 pm
by markzvo
I have a Pi 5 with NVMe storage so my setup is VERY fast... so I only saw this issue once. But no more after Sleep 3.
Try Sleep 20? Anything longer than that and you may have a different issue such as a display that is not Linux-friendly.
Re: No Screen but Web interface
Posted: Mon Nov 11, 2024 11:50 pm
by tdunlop
Has there been any resolution to this problem? I'm having the same issue on a pi4 4GB. No web interface and no screen on the latest image (20241101). I tried rolling back to an earlier image (20230519) and was able to get the web interface working but had no screen. I tried making adjustments to /usr/sbin/qlcplus-start.sh but no luck. I'm more than willing to tinker with things, so if you have any suggestions I'm all ears.
Re: No Screen but Web interface
Posted: Tue Nov 12, 2024 7:33 am
by mcallegari
tdunlop wrote: ↑Mon Nov 11, 2024 11:50 pm
Has there been any resolution to this problem? I'm having the same issue on a pi4 4GB. No web interface and no screen on the latest image (20241101). I tried rolling back to an earlier image (20230519) and was able to get the web interface working but had no screen. I tried making adjustments to /usr/sbin/qlcplus-start.sh but no luck. I'm more than willing to tinker with things, so if you have any suggestions I'm all ears.
Might be the same of this?
https://www.qlcplus.org/forum/viewtopic.php?t=17877
Are you customizing the image when flashing it?
Re: No Screen but Web interface
Posted: Tue Nov 26, 2024 7:45 pm
by vicat56
Peetem wrote: ↑Wed Oct 16, 2024 8:50 pm
markzvo wrote: ↑Sun Sep 15, 2024 5:28 am
I have seen this behavior as well, some boots do not work properly because the display is not yet detected... I will probably have to add
sleep 3 to
/usr/sbin/qlcplus-start.sh file before the HDMI detection logic
Did this work? How was it done?
Still can't get mine to recognize the display....
I'm a bit late... Yes the issue was my "slow" screen. so a timer was the way to go for me.
Re: No Screen but Web interface
Posted: Wed Dec 18, 2024 5:32 pm
by stockers
I am seeing similar problems, using the latest release, a PI 5 with an official raspberry PI touch screen (original). I have set the delay to both 3 and 20.
1 time out of every 5 to 10, it will start properly with the screen displaying properly. the rest of the time, it shows the command prompt and does not start QLC. disconnecting and reconnecting the power a number of times eventually resolvesthe issue.
If I add the line QTPLATFORM="linuxfb" after the autodetect in qlcplus-start.sh, it works every time, but the screen is not usable (wrong fonts and sizes for tabs, etc.). If i manually set it to "eglfs" (i.e. bypass the detection and force a screen) I get the same unreliable startup.
Not sure what is going on as I make no changes between it working and failing...