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Controlling Raspberry Pi 2 LEDs

Commands for controlling the Raspberry Pi 2 LEDs.

See rpi-leds for a node module that does this.

Power (PWR) LED

  • OK (ACT) LED = led0
  • Power (PWR) LED = led1

Allow access

echo gpio | sudo tee /sys/class/leds/led0/trigger
echo gpio | sudo tee /sys/class/leds/led1/trigger

Heartbeat effect

echo heartbeat | sudo tee /sys/class/leds/led0/trigger
echo heartbeat | sudo tee /sys/class/leds/led1/trigger

Timer effect

echo timer | sudo tee /sys/class/leds/led0/trigger
echo timer | sudo tee /sys/class/leds/led1/trigger

Turn on/off

echo 1 | sudo tee /sys/class/leds/led0/brightness
echo 0 | sudo tee /sys/class/leds/led0/brightness

echo 1 | sudo tee /sys/class/leds/led1/brightness
echo 0 | sudo tee /sys/class/leds/led1/brightness

Revert back to default setting

echo input | sudo tee /sys/class/leds/led1/trigger
echo mmc0 | sudo tee /sys/class/leds/led0/trigger

Notes

Resources

LED trigger original values:

pi@raspberrypi ~ $ cat /sys/class/leds/led1/trigger
none mmc0 timer oneshot heartbeat backlight gpio cpu0 cpu1 cpu2 cpu3 default-on [input] rfkill0
pi@raspberrypi ~ $ cat /sys/class/leds/led0/trigger
none [mmc0] timer oneshot heartbeat backlight gpio cpu0 cpu1 cpu2 cpu3 default-on input rfkill0

wsmoak commented Dec 25, 2015

On a Raspberry Pi 2 Model B purchased from Adafruit (with their pre-loaded card) I found that the green led is controlled with /sys/class/leds/ACT/trigger and /brightness. The ACT directory is a symlink, and the files are only writeable by root.

$ cat /sys/class/leds/led1/trigger
none mmc0 timer oneshot heartbeat backlight gpio cpu0 default-on [input]
$ 

What does that do??

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