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.
- for nrf52840, use S140.
- Softdevice should be programmed using nrf Connect -> Programmer.
- Softdevice location under the main nrf folder: \components\softdevice\s140\hex
- 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.