The digital IO shield allows you to add 16 more gpios to the already existing ones of your Linino board. The shield is equipped with 8 Leds, 4 Relays and 4 push buttons as follows:

To enable the digitalIO shield you can run this command:

root@linino:~# echo digitalio > /sys/devices/mcuio/shield_register

If the shield registration is successful, you will be able to detect gpiochip216 in the following sysfs path :

root@linino:~# ls /sys/class/gpio/
export       gpio22       gpiochip0         gpiochip216
gpio21       gpio23       gpiochip100    unexport

to enable the use of a given push button, you first have to export its correspondig gpio (i.e. push button 1 on the gpio 216):

root@linino:~# echo 216 > /sys/class/gpio/export

set the gpio direction in input mode:

root@linino:~# echo in > /sys/class/gpio/gpio216/direction

and then you can read the input value:

root@linino:~# cat /sys/class/gpio/gpio216/value
0

To read the push button state in nodejs, run the following script:

to enable the use of a given led, you first have to export its correspondig gpio (i.e. Led 5 on the gpio 228):

root@linino:~# echo 228 > /sys/class/gpio/export

set the gpio direction in output mode:

root@linino:~# echo out > /sys/class/gpio/gpio228/direction

and then turn the led on by running this command:

root@linino:~# echo 1 > /sys/class/gpio/gpio228/value

to enable the use of a given relay, you first have to export its correspondig gpio (i.e. Relay 1 on the gpio 224):

root@linino:~# echo 224 > /sys/class/gpio/export

set the gpio direction in output mode:

root@linino:~# echo out > /sys/class/gpio/gpio224/direction

then, you can change relay's state by writing “1” or “0” in the “value” field:

root@linino:~# echo 1 > /sys/class/gpio/gpio224/value