NanoPi Neo: Enable function of blue status LED

Community Tutorials
1

By default on NanoPi Neo, the blue system LED is always off and has no function.

Update:

  • Since DietPi v.143 blue LED is heartbeat for H3 now functional and applied during boot.

Hint:

  • this will ONLY work with Legacy kernel images (3.4x) at the moment
  • NOT with Mainline kernel images (4.9.x) ==>> green Power LED will start blinking, if device is ready for login
root@NanoPi-Neo:~# uname -r

List available options:

root@NanoPi-NEO:~# cat /sys/class/leds/blue_led/trigger



[none] mmc0 timer heartbeat backlight default-on

Example: Turn off

echo 0 >/sys/class/leds/blue_led/brightness
echo none >/sys/class/leds/blue_led/trigger

Example: link to Heartbeat usage

echo 1 >/sys/class/leds/blue_led/brightness
echo heartbeat >/sys/class/leds/blue_led/trigger

Example: link to SD usage (Note: Only after completely booting up device! )

echo 1 >/sys/class/leds/blue_led/brightness
echo mmc0 >/sys/class/leds/blue_led/trigger

To get this blue LED changes persistent on every boot, you have to edit /etc/rc.local

Make a backup:

cp /etc/rc.local /etc/rc.local.bac

Edit:

nano /etc/rc.local

Add following lines before "exit 0 ":
[Example - edit or uncomment line you needed.]

#### switch on blue LED for sd-card activity
echo 1 >/sys/class/leds/blue_led/brightness
echo mmc0 >/sys/class/leds/blue_led/trigger

#### switch on blue LED for heartbeat 
## echo 1 >/sys/class/leds/blue_led/brightness
## echo heartbeat >/sys/class/leds/blue_led/trigger

#### switch off blue LED 
## echo 0 >/sys/class/leds/blue_led/brightness
## echo none >/sys/class/leds/blue_led/trigger

exit 0
2

On a roll with the LED’s k-plan :smiley:. Nice one!

3

So i’d love to see if someone gets this running on 4.14. I’ve had issues with my nanopi neo locking up and i had no idea it stopped. I need to always be sure it is runnin at a glance. Maybe a blue led flashing i can see from across the room? or maybe a screen popup on the oled every 5 minutes or so? i dunno. but something to let me know it’s working. I like the idea of the heartbeat led but as you say it doesnt work on 4.14