You can install the Adafruit Bluefruit nRF52 BSP (Board Support Package) in two steps:

1. BSP Installation

Recommended: Installing the BSP via the Board Manager

• Download and install the Arduino IDE (At least v1.8)
• Start the Arduino IDE
• Go into Preferences
• Add https://adafruit.github.io/arduino-board-index/package_adafruit_index.json as an 'Additional Board Manager URL' (see image below)

• Restart the Arduino IDE
• Open the Boards Manager option from the Tools -> Board menu and install 'Adafruit nRF52 by Adafruit' (see image below)

It will take up to a few minutes to finish installing the cross-compiling toolchain and tools associated with this BSP.

The delay during the installation stage shown in the image below is normal, please be patient and let the installation terminate normally:

Once the BSP is installed, select

• Adafruit Bluefruit nRF52832 Feather (for the nRF52 Feather)
• Adafruit Bluefruit nRF52840 Feather Express (for the nRF52840 Feather)
• Adafruit ItsyBitsy nRF52840 (for the Itsy '850)
• Adafruit Circuit Playground Bluefruit (for the CPB)
• etc...

from the Tools -> Board menu, which will update your system config to use the right compiler and settings for the nRF52:

2. LINUX ONLY: adafruit-nrfutil Tool Installation

adafruit-nrfutil is a modified version of Nordic's nrfutil, which is used to flash boards using the built in serial bootloader. It is originally written for python2, but have been migrated to python3 and renamed to adafruit-nrfutil since BSP version 0.8.5.

Install python3 if it is not installed in your system already

$ sudo apt-get install python3

$ sudo apt-get install python3

Then run the following command to install the tool from PyPi

$ pip3 install --user adafruit-nrfutil

$ pip3 install --user adafruit-nrfutil

Add pip3 installation dir to your PATH if it is not added already. Make sure adafruit-nrfutil can be executed in terminal by running

$ adafruit-nrfutil version
adafruit-nrfutil version 0.5.3.post12

$ adafruit-nrfutil version
adafruit-nrfutil version 0.5.3.post12

3. Update the bootloader (nRF52832 ONLY)

To keep up with Nordic's SoftDevice advances, you will likely need to update your bootloader if you are using the original nRF52832 based Bluefruit nRF52 Feather boards.

Follow this link for instructions on how to do that

Advanced Option: Manually Install the BSP via 'git'

If you wish to do any development against the core codebase (generate pull requests, etc.), you can also optionally install the Adafruit nRF52 BSP manually using 'git', as decribed below:

Adafruit nRF52 BSP via git (for core development and PRs only)

1. Install BSP via Board Manager as above to install compiler & tools.
2. Delete the core folder nrf52 installed by Board Manager in Adruino15, depending on your OS. It could be
   macOS: ~/Library/Arduino15/packages/adafruit/hardware/nrf52
Linux: ~/.arduino15/packages/adafruit/hardware/nrf52
Windows: %APPDATA%\Local\Arduino15\packages\adafruit\hardware\nrf52
3. Go to the sketchbook folder on your command line, which should be one of the following:
   macOS: ~/Documents/Arduino
Linux: ~/Arduino
Windows: ~/Documents/Arduino
4. Create a folder named hardware/Adafruit, if it does not exist, and change directories into it.
5. Clone the Adafruit_nRF52_Arduino repo in the folder described in step 2:
   git clone --recurse-submodules [email protected]:adafruit/Adafruit_nRF52_Arduino.git

6. This should result in a final folder name like ~/Documents/Arduino/hardware/Adafruit/Adafruit_nRF52_Arduino (macOS).

7. Restart the Arduino IDE