Crazflie 2.0 bootloader firmware that runs in the nRF51. See readme.md in crazyflie-nrf-firmware repos for more information about flash and boot architecture.
Compiling with this program currently requires the nRF51_SDK and S110 packages. These can be downloaded from the Nordic semiconductor website. See s110/readme and nrf51_sdk/readme for exact version.
Most of the code is licensed under LGPL-3.0.
Some files under src/ble/ are modified from Nordic semiconductor examples.
Downloading the nrf51_sdk and nordic S110 softdevice require to aquire one of the Nordic Semiconductor development kit. Discussion is in progress with Nordic to solve this situation.
To compile arm-none-eabi- tools from https://launchpad.net/gcc-arm-embedded should be in the path.