The debugger does not need any driver for Mac OS. But it does need LibUSB driver for the debugging/programming interface on Windows. Using Zadig to install the libusb-win32 driver. Then select Burn ...
Crazflie 2.0 bootloader firmware that runs in the nRF51. See readme.md in crazyflie2-nrf-firmware repo for more information about flash and boot architecture. In order to work on this bootloader, you ...