==Peripheral GPIOs ==
Nel In [[ETRA_SOM | ETRA SOM è presente un ]] there is an I/O Expander piloatato driven via i2c, non è presente un with this ETRA can handle external pins in many different ways and most of them can be configured as GPIOs, these GPIOs are present in the J11 connector.There is no driver per configurare e usare questi gpio liberamenteto configure and use these GPIOs, questi gpio sono presenti nel pettine J11to configure and write/read the GPIOs you need to interact with I/O expander with i2c commands.
ETRA can handle external pins in many different ways and most of them can be configured as GPIOs. When a pin is set as a GPIO, it is possibleto read its value, change its direction or change output value directly from the shell. ===Accessing the peripheral===
==== Usage with i2c command ====