I am using Magic Mirror together with my Raspberry Pi 3B+ (Buster) and an old laptop monitor. The website is displayed using kiosk mode with chromium. When my RPi normally starts, the monitor is turned off. That's why I've added hdmi_force_hotplug=1 to /boot/config.txt. But this doesn't work, somehow the hdmi output is off and the monitor says no signal detected. I've also set several settings to match my monitor settings:
/boot/config.txt
# uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1
# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
disable_overscan=1
# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
#overscan_right=16
#overscan_top=16
#overscan_bottom=16
# uncomment to force a console size. By default it will be display's size minus
# overscan.
#framebuffer_width=1280
#framebuffer_height=800
# use edid_file in boot folder
#hdmi_edid_file=1
# uncomment if hdmi display is not detected and composite is being output
hdmi_force_hotplug=1
# uncomment to force a specific HDMI mode (this will force VGA)
hdmi_group=2
hdmi_mode=28
# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
#hdmi_drive=2
# uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
#config_hdmi_boost=9
# uncomment for composite PAL
#sdtv_mode=2
#uncomment to overclock the arm. 700 MHz is the default.
#arm_freq=800
# Uncomment some or all of these to enable the optional hardware interfaces
#dtparam=i2c_arm=on
#dtparam=i2s=on
#dtparam=spi=on
# Uncomment this to enable infrared communication.
#dtoverlay=gpio-ir,gpio_pin=17
#dtoverlay=gpio-ir-tx,gpio_pin=18
# Additional overlays and parameters are documented /boot/overlays/README
# Enable audio (loads snd_bcm2835)
dtparam=audio=on
[pi4]
# Enable DRM VC4 V3D driver on top of the dispmanx display stack
# Next line commented out, cuz dtoverlay=vc4-kms-v3d is now in use
#dtoverlay=vc4-fkms-v3d
max_framebuffers=2
[all]
#dtoverlay=vc4-fkms-v3d
# Magic Mirror added
dtoverlay=vc4-kms-v3d
avoid_warnings=1
But this is not working, if I turn the monitor on after boot, it says no signal detected.
I even tried a workaround by turning it after boot on with the command:
pi@himbipi:~ $ sudo /opt/vc/bin/tvservice -p
Powering on HDMI with preferred settings
[E] Failed to power on HDMI with preferred settings
But without success. It's strange, that the poweroff doesn't show any error and the monitor is staying on though:
pi@himbipi:~ $ sudo /opt/vc/bin/tvservice -o
Powering off HDMI
Maybe the settings in /etc/xdg/lxsession/LXDE-pi/autostart are influencing the behaviour?
pi@himbipi:/boot $ cat /etc/xdg/lxsession/LXDE-pi/autostart
@lxpanel --profile LXDE-pi
@pcmanfm --desktop --profile LXDE-pi
# Bildschirmschoner deaktivieren
#@xscreensaver -no-splash
@xset s noblank
@xset s off
@xset -dpms
# Bildschirm drehen
@xrandr --output HDMI-1 --rotate right
# Mauszeiger ausblenden
@unclutter -display :0 -idle 3 -root -noevents
# lädt Chromium im Vollbild bei einem Neustart
@chromium-browser --no-default-browser-check --check-for-update-interval=604800 --disable-pinch --incognito --kiosk http://localhost:80
At this point I don't have a clue, can anyone help me please? :)
Thank you very much
