Programming Softdevice - Noaman-strat/nrf5 GitHub Wiki

For most custom code and/or board (especially when using Raytac modules) softdevice needs to be programmed on the board.

1. for nrf52840, use S140.
2. Softdevice should be programmed using nrf Connect -> Programmer.
3. Softdevice location under the main nrf folder: \components\softdevice\s140\hex
4. Erase and write.

Do not mix softdevices from different SDK versions. there are api compatibility as well as softdevice size differences that can cause problems.