HDMI

Neither X11, nor wayland but framebuffer is used as our default graphical backend which can be used by gstreamer for video output or Qt5 to have a fully fledged GUI.

Connect HDMI monitor while booting and watch the graphical boot sequence. More: framebuffer.

Add/enable the following lines in config.txt:

hdmi_force_hotplug=1 
hdmi_drive=2
hdmi_group=1

• hdmi_force_hotplug to enable HDMI even if no HDMI monitor is detected
• hdmi_drive send audio over HDMI
• hdmi_group enable CEA HDMI modes

You may also set a specific hdmi_mode and disable overscan area to have a FullHD 1920x1080@60Hz resolution:

disable_overscan=1 
hdmi_mode=16

Note:

• for 720p @ 60Hz use mode: 4
• There is a raspi specific software tvservice which will not be discussed here.