Labs

File System Labs

GPIO (General Purpose Input Output)

root@board:~# dmesg | grep -i gpio
root@board:~# ls /sys/class/gpio/
root@board:~# ls /sys/class/gpio/gpio13
root@board:~# echo 13 > /sys/class/gpio/export

root@board:~# ls /sys/class/gpio/gpio13
active_low  direction  drive  edge  power  subsystem  uevent  value

root@board:~# echo in > /sys/class/gpio/gpio13/direction
root@board:~# echo out > /sys/class/gpio/gpio13/direction
root@board:~# echo 1 > /sys/class/gpio/gpio13/value
root@board:~# cat /sys/class/gpio/gpio13/value    
root@board:~# echo 0 > /sys/class/gpio/gpio13/value
root@board:~# cat /sys/class/gpio/gpio13/value

I2C (Inter-IC)

root@board:~# dmesg | grep -i i2c

root@board:~# ls /sys/class/i2c-dev/
i2c-0 i2c-1  i2c-2  i2c-3  i2c-4  i2c-5  i2c-6  i2c-7

root@board:~# i2cdetect -y -r <Bus>
root@board:~# i2cdump -f -y <Bus> <0xAddress>