Using Manual Custom-built Mode(N2/C4/HC4)

If your monitor doesn't work automatically because you have a special Monitor, not VESA standards or you want to use a specific resolution, set the custom-built mode.
To use the Custom-built mode, you need ModeLine information. We are going to use the 480×1280 monitor as an example.

If you are using an old Ubuntu image so you don't have the config.ini file in the partition, check “boot.ini”.

Set the "display_autodetect" to "false" in config.ini


Set the "hdmimode" to "custombuilt" in config.ini


Set the ModeLine value

We already found the “modeline” value of 480×1280 monitor in the following link.
How to get monitor information(Modeline)

modeline= "horpixels,verpixels,pixel_clock,hor_freq,ver_freq,hdisp,hsyncstart,hsyncend,htotal,vdisp,vsyncstart,vsyncend,vtotal,hsync_polarity,vsync_polarity,progress_mode"

Please be sure of units for pixel_clock, hor_freq and ver_freq.

  • pixel_clock : in KHz unit, ex) 56.4MHz → 56400
  • hor_freq : in Hz unit ex) 78.333KHz → 78333
  • ver_freq : in Hz unit ex) 60Hz → 60

Add the line in config.ini file


Reboot your system.

sudo reboot

After the reboot, you can verify with this command if it is applied well.

odroid@odroid:~$ cat /sys/class/display/mode
  • common/hdmi_howto/custombuilt.txt
  • Last modified: 2021/04/09 12:09
  • by john1117