BOSSAC (the command line version of BOSSA) is the tool that is used to flash firmware onto SAM microcontrollers via the bootloader. FortyTwo Systems has its own version of this utility which includes support for the SAMC21/SAMC21N microcontrollers.

Build process


Start by cloning the repository. You don’t need to have wxWidgets installed on your system since you’re only building the CLI.

git clone

Compile BOSSAC

Navigate into the BOSSA folder. To build the program, run

make arduino HOST=hostname

Fill “hostname” according to the following list:

  • ARM Linux 32-bit (arm-linux-gnueabihf),

  • ARM Linux 64-bit (aarch64-linux-gnu),

  • macOS 64-bit (x86_64-apple-darwin),

  • Windows (i686-mingw32),

  • Linux 32-bit (i686-linux-gnu),

  • Linux 64-bit (x86_64-linux-gnu)

To override the version coded into the Makefile, add VERSION=version to the above command

Finishing Up

There should now be a compressed (.tar.bz2) binary in the BOSSA folder, as well as a file named package_bossac_1.9.1-fortytwo-0_hostname_index.json. Copy and paste the relevant lines from that file into the json that should have come with the repo. Once you’ve compiled across all your target operating systems, you can upload the compressed binaries plus the single json file to your file server.