I've installed Ubuntu 16.04 on my Asus X555LJ.

But I don't know how to install drivers or how to enable function keys to controls screen backlight brightness.

  • any news? I would be interested to know if you found anything as it might work for me too :) – Zanna Aug 5 '16 at 17:24
  • No, Now News On That. Currently I Using Solution Suggested By You :) – Mek Vala Aug 8 '16 at 7:56
  • :) I'll remember to come back here and let you know if I hear of a better way! – Zanna Aug 8 '16 at 7:58

It seems quite common for brightness Fn keys to not work on Asus machines. On my Asus X205TA the brightness function keys don't work natively but I can use xbacklight as a workaround:

sudo apt install xbacklight


get current brightness:

xbacklight -get 

set brightness to 50%

xbacklight -set 50

increase brightness by 10%

xbacklight -inc 10

decrease by 10%

xbacklight -dec 10

If these work, you can get the function keys to change brightness by assigning them as shortcuts to the commands.

In keyboard settings click Custom Shortcuts and click the + button to add a new one

Name: Brighter
Command: xbacklight -inc 15

Click OK, then click where it says 'Disabled' next to the new shortcut and press the key combination you want (Fn will probably not work) for example ctrl+F6 or just F6

Name: Dimmer
Command: xbacklight -dec 15

And make this one F5 or whatever combination you want.

  • How Do I Set F5 Or F6 Key with function button? Because this works without pressing function key. – Mek Vala Jul 15 '16 at 7:38
  • When you click to set the shortcut, just hold the Fn key and press F5 at the the same time, does that work? Sometimes the Fn key can be tricky... – Zanna Jul 15 '16 at 7:42
  • No, Tried Holding Function Key + F5/F6 . But System Doesn't take it. – Mek Vala Jul 15 '16 at 7:46
  • 1
    For me, i was able to xbacklight -dec until the screen went off, so i wrote a small bash script to run instead that adds a lower limit of 10%. – Scimonster Aug 26 '16 at 9:15
  • 1
    a=$(xbacklight);printf -v a %.0f "$a";b=10;if [ "$a" -gt "$b" ];then xbacklight -dec 5;fi; It limits it at 10 (b=10) and decrements by 5% each time. – Scimonster Aug 26 '16 at 9:38

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