Examples Using EV3DEV

Here you can find examples, how to use the EV3DEV kernel drivers. The examples are using only echo and cat from the command line, but it is possible to write and read the same files with other programming languages. Before you can start, boot from SD card, open an SSH connection, and login. If you do not have an SSH connection already, go back to Home how to do this.

Turning On LEDs

The following example shows, how to turn on the right green LED. In the same way you can use all LEDs (left green, right green, left red, right red). You can see an orange LED, if the red and green LED has been turned on at the same side.

Deactivate LED Trigger

Before using the LED it is necessary to deactivate the LED trigger (for heartbeat, ...), e.g. you can deactivate the trigger for the right green LED with

echo none > /sys/class/leds/ev3\:green\:right/trigger

This can be verified with

cat /sys/class/leds/ev3\:green\:right/trigger

Turning LED On and Off

Turn on the right green LED:

echo 1 > /sys/class/leds/ev3\:green\:right/brightness

Turn off the right green LED:

echo 0 > /sys/class/leds/ev3\:green\:right/brightness