Hi !

I am running deb stretch server on OPi Zero LTS. To control LEDs I tried to follow this thread https://forum.armbian.com/topic/6306-orange-pi-zero-h2-status-led/

So if I edit the file /sys/class/leds/orangepi:green:pwr/trigger to select "cpu" but I get the following

 

opi@orangepizero:/$ sudo echo "power" > /sys/class/leds/orangepi:green:pwr/trigger
-bash: /sys/class/leds/orangepi:green:pwr/trigger: Permission denied

With root as user, this is what I get

root@orangepizero:/# echo "power" > /sys/class/leds/orangepi:green:pwr/trigger
bash: echo: write error: Invalid argument

however, if I edit the file using nano and delete all contents and then type cpu then it gets saved and green led shows intended status.

Whats the standard procedure to do this??

1 hour ago, Aditya said:

Whats the standard procedure to do this??

When using "sudo", it only affect the left part, here "echo", everything at right of ">" isn't "sudo" applied ...

So, if you wish to use "sudo", syntax would be :

echo "default-on" | sudo tee /sys/class/leds/orangepi:green:pwr/trigger

Note here : "power" is not an available choice, do "cat /sys/class/leds/orangepi:green:pwr/trigger", it will show you all possible choices and the current setting is indicated with brackets. The choice you probably wish is "default-on".

 

Thanks a lot. It works fine.

It asked for a password when I entered the command like you just told, so how to use this command in rc.local or how to execute it at boot??

Edit:

Simply added the line to /etc/rc.local

Thanks again btw