Board module

The board module is used to ensure the proper state of GPIO pins that are not configured by other modules in the application. Ensuring the proper state is done by setting the state of the mentioned pins on the system start and wakeup, and when the system enters the low-power mode.

Module events

Source Module	Input Event	This Module	Output Event	Sink Module
Source modules for module_state_event	module_state_event	board
Power manager module	power_down_event
Bluetooth LE advertising module	wake_up_event
Buttons module
HID forward module
Motion module
Power manager module
Wheel module
			module_state_event	Sink modules for module_state_event

Note

See the Application overview for more information about the event-based communication in the nRF Desktop application and about how to read this table.

Configuration

The module uses Zephyr’s General-Purpose Input/Output (GPIO) driver to set the pin state. For this reason, set the CONFIG_GPIO option.

For every configuration, you must define the port_state_def.h file in the board-specific directory in the application configuration directory.

The port_state_def.h file defines the states set to the GPIO ports by the following arrays:

• port_state_on - State set on the system start and wakeup.

• port_state_off - State set when the system enters the low-power mode.

Every port_state refers to a single GPIO port and contains the following information:

• port_state.name - GPIO device name (obtained from devicetree, for example with DT_LABEL(DT_NODELABEL(gpio0))).

• port_state.ps - Pointer to the array of pin_state.

• port_state.ps_count - Size of the ps array.

Every pin_state defines the state of a single GPIO pin:

• pin_state.pin - Pin number.

• pin_state.val - Value set for the pin.

You can use the CONFIG_DESKTOP_BOARD_PM_EVENTS Kconfig option to enable or disable handling of the power management events, such as power_down_event and wake_up_event. The option is enabled by default and depends on the CONFIG_CAF_PM_EVENTS Kconfig option.