{{indexmenu_n>1}}

====== GPIO Header ======

===== GPIO usage examples =====

<WRAP important >
Please make sure that the GPIOs you want to use are not configured as other functions, if they are, you can follow [[products:sbc:common:configurations:device-tree-overlay|Device Tree Overlay]] to configure them as normal GPIOs.
</WRAP>

When you get the GPIO number, you can follow the steps below to control it. Here we take GPIO number ''465'' as an example.

==== Export GPIO ====

```shell
$ echo 465 | sudo tee /sys/class/gpio/export
```

==== Set-up GPIO direction ====

We can configure direction as input or output.

```shell
$ echo out | sudo tee /sys/class/gpio/gpio465/direction # Set GPIO output
$ echo in  | sudo tee /sys/class/gpio/gpio465/direction # Set GPIO input
```

==== Set GPIO value ====

```shell
$ echo 1 | sudo tee /sys/class/gpio/gpio465/value # Set GPIO output high
$ echo 0 | sudo tee /sys/class/gpio/gpio465/value # Set GPIO output low
```

==== Get GPIO value ====

```shell
$ cat /sys/class/gpio/gpio465/value # Get GPIO input value
```

==== Unexport GPIO ==== 

```shell
$ echo 465 | sudo tee /sys/class/gpio/unexport
```

==== Troubleshooting ====

If you got the similar error below, it means that the PIN you try to export is used for another function, you need to edit [[products:sbc:common:configurations:device-tree-overlay|Device Tree Overlay]] configuration file to set the PIN as normal GPIO.

```shell
khadas@Khadas:~$ echo 465 | sudo tee /sys/class/gpio/export 
tee: /sys/class/gpio/export: Invalid argument
```