Device description module¶
The device description module defines custom GATT Service, which contains:
Information about whether the peripheral supports the Low Latency Packet Mode (LLPM)
Hardware ID (HW ID) of the peripheral
In order to support the LLPM, the peripheral must use the SoftDevice Link Layer (CONFIG_BT_LL_SOFTDEVICE
) and CONFIG_DESKTOP_BLE_USE_LLPM
Kconfig option must be enabled.
The Service is mandatory for all nRF Desktop peripherals that connect to the nRF Desktop centrals.
Module events¶
The dev_descr
module does not submit any event nor subscribe for any event.
Configuration¶
The module uses Zephyr’s Hardware Information to obtain the hardware ID.
Enable the required driver using CONFIG_HWINFO
.
The module is enabled by default for all nRF Desktop peripheral devices.
The dev_descr.h
file contains the UUIDs used by the custom GATT Service.
The file is located in the configuration/common
directory.
The UUIDs must be the same for all devices to ensure that the central is able to read the provided information.
Implementation details¶
The module uses BT_GATT_SERVICE_DEFINE
to define the custom GATT Service.
More detailed information regarding GATT are available in Zephyr’s Generic Attribute Profile (GATT) documentation.