LED Class Directory
Interfaces
Default Trigger
/sys/class/leds/led4/
User LED4
none
The locations of the user LEDs seen from the exterior of Armadillo-IoT are shown below.
Figure 5.41. User LEDs Location
In the following explanation, the LED class directory representing an arbitrary LED is written as
/sys/class/leds/
[LED]
.
5.4.1. Activating and Deactivating LEDs
An LED can be turned on and off by writing a value to the brightness file under the LED class directory. Valid values to
write to brightness are between 0 and 255.
Writing a value other than 0 to brightness turns the LED on.
[armadillo ~]# echo 1 > /sys/class/leds/[LED]/brightness
Figure 5.42. Turning on an LED
Since the LEDs on Armadillo-IoT do not have brightness control functionality only
two states, 0 (off) and 1-255 (on), can be specified.
Writing 0 to brightness turns the LED off.
[armadillo ~]# echo 0 > /sys/class/leds/[LED]/brightness
Figure 5.43. Turning off an LED
The state of an LED can be obtained by reading brightness.
Armadillo-IoT Gateway G3Product Manual - INTL
Operational Checks
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