1. I'm using Ubuntu running on the BBB board for this article. First login into the board and become root with command ...
2. Access to /sys/class/leds , you can find 4 folders that contain control files for all USER 4 LEDs.
3. Let's control LED number 4 (the one that placed next to the Ethernet Port). Access the beaglebone:green:usr3 folder.
4. You can see the values inside control files with cat command.
5. Use this comand to turn On/Off LED
# echo 1 > brightness
# echo 0 > brightness
6. To blinking the LED, use this command ...
# echo timer > trigger
# echo 1000 > delay_off
# echo 500 > delay_on
That is for today. See you next time :)