If I understand your comment correctly, you are looking for more hardware related information, e.g. how to access a certain port pin.
The provided example and all the documentation is focused on the integration of the underlying system and how to access hardware drivers or other software stacks.
For all hardware related aspects (GPIOs, port configurations, etc.) please have a look to the examples and documentations provided by the chip / BSP manufacturer.
Best regards,
Manfred.