Hi

8.04 all working nice and stable on my new Acer 4810t dual core, but still with some outstanding issues.

I haven't found a way to get the brightness to change at all, am wondering if anyone can help.

Looking around the brightness control could be here:

/proc/acpi/video/VGA/LCD/brightness

and if I try

cat /proc/acpi/video/VGA/LCD/brightness

I get something like

~$ cat /proc/acpi/video/VGA/LCD/brightness

levels:  100 80 30 40 50 60 70 80 90 100

current: 70

which I've just noticed is controlled by the hotkeys. Unfortunately it has no effect on the brightness. Using the echo command has no effect on it.

There is also

/sys/class/backlight/acer_acpi/brightness

and if I try

cat /sys/class/backlight/acer_acpi/brightness

I get

9

but echo changes nothing.

There is also

/proc/acpi/acer/brightness

and if I try

cat /proc/acpi/acer/brightness

I get

8

but the echo command makes no difference.

Any ideas where I'm going wrong?

Jim

Thanks for getting back to me

I try this

sudo echo 7 /sys/class/backlight/acer_acpi/brightness

which, after giving the password, gives me

7 /sys/class/backlight/acer_acpi/brightness

But then, if I check with

cat /sys/class/backlight/acer_acpi/brightness

the answer still comes back as

9

Hi

Not very good with the Command Line, me.

I thought that you'd solved it, but I'm afraid it made no difference. I've tried with the different 'brightness' files that I have found and simply get 'Permission Denied' even when I try it as root. Here's a copy:

~$ cat /proc/acpi/video/VGA/LCD/brightness

levels:  100 80 30 40 50 60 70 80 90 100

current: 100

~$ echo 40>/proc/acpi/video/VGA/LCD/brightness

bash: /proc/acpi/video/VGA/LCD/brightness: Permission denied

~$ sudo echo 40>/proc/acpi/video/VGA/LCD/brightness

bash: /proc/acpi/video/VGA/LCD/brightness: Permission denied

However, I can use the function keys on the keyboard to change this value (above), though it has no effect on the actual screen brightness.

~$ cat /sys/class/backlight/acer_acpi/brightness

9

~$ echo 4>/sys/class/backlight/acer_acpi/brightness

bash: /sys/class/backlight/acer_acpi/brightness: Permission denied

~$ sudo echo 4>/sys/class/backlight/acer_acpi/brightness

bash: /sys/class/backlight/acer_acpi/brightness: Permission denied

And finally...

~$ cat /proc/acpi/acer/brightness

6

~$ echo 2>/proc/acpi/acer/brightness

bash: /proc/acpi/acer/brightness: Permission denied

~$ sudo echo 2>/proc/acpi/acer/brightness

bash: /proc/acpi/acer/brightness: Permission denied

:(

Jim