Switching to a custom nRF52840 board for nRF Desktop App

Question

I'm trying to configure the nRF Desktop Application for an Adafruit nRF52840 Feather that's plugged into a custom FeatherWing. The nRF52840 Feather is a supported board so I just used that in the configuration page of the VS Code extension. I copied the nrf52840dk_nrf52840 prf.conf file over to a ./configuration/adafruit_feather_nrf52840/ folder. The build fails because there are two warnings: 
 If I set CONFIG_LED_PWM=n then the first warning goes away but that doesn't seem like a proper solution. USB_HID_PROTOCOL_CODE should be set because DESKTOP_HID_BOOT_INTERFACE_MOUSE is set to y. Is there something obvious that I'm missing? Is nRF Desktop not supposed to be altered? Is it better to start a from scratch project and pull in modules and drivers where I need them?

Marte Myrvold · Accepted Answer

Hi, 
 Most of the errors in the build log come from missing devicetree configurations, i.e. things that should be defined in app.overlay. However, the configuration files for the nRF52840 DK cannot be directly used for the Adafruit Feather nRF52840, since they are not compatible. For example, the Adafruit Feather only has the reset button compared to the DK's four user buttons, and it only has 2 user LEDs while the nRF52840 has 4. You will have to change the configuration files, and possibly also the nRF Desktop application itself, to correspond with what is supported by the Adafruit Feather. It might be a good starting point to look at the configuration files for the nRF52840 Dongle instead, as that would be more similar to the Adafruit Feather than the DK. 
 Best regards, Marte

Switching to a custom nRF52840 board for nRF Desktop App

Top Replies