From Technologic Systems Manuals
There are four LEDS on the TS-7180 that may be controlled by the user, through the sysfs interface. These are colored yellow, green, red, and blue.
To turn an LED on, write a 1 to 'brightness'. To turn it off again, write a 0.
# Example: Turn on the Blue LED... echo 1 > /sys/class/leds/blue-led/brightness # Turn it off again... echo 0 > /sys/class/leds/blue-led/brightness