BBB: About setting up display of BBB

Embedded Linux Discussions
1

Hi I am using 7 inch LCD monitor using HDMI with Beaglebone black
I want to change display resolution
so I entered the following, but an error occurred.

debian@arm:~$ xrandr
Can't open display
debian@arm:~$ export DISPLAY=:0
debian@arm:~$ xrandr
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 1024 x 600, current 1024 x 600, maximum 1024 x 600
default connected 1024x600+0+0 0mm x 0mm
   1024x600       0.00*
debian@arm:~$ xrandr -q | grep " connected"
xrandr: Failed to get size of gamma for output default
default connected 1024x600+0+0 0mm x 0mm
debian@arm:~$ xrandr --output HDMI-0 --mode 1024x600 --rate 60
xrandr: Failed to get size of gamma for output default
warning: output HDMI-0 not found; ignoring
debian@arm:~$

How can I fix this error message. xrandr: Failed to get size of gamma for output default
and how can I fix next error. warning: output HDMI-0 not found; ignoring

Can you resolve them for me?
and Can you help me to change display resolution?

2

It looks like your LCD only supports one mode, 1024x600 and doesn’t report Frequency nor anything else over the EDID bus… You could try a 5.10.x based kernel to see if there was a fix for this, or the hardware only reports resolution…

Regards,

3

Thank you for your help.
I will try it.