It keeps compatibility with the XIAO bootloader by:
- using Soft Device 7.3.0
- reserving 48k memory for the bootloader.
So on double reset a drive pops for uploading an uf2 image or a nrfutil zip
pkg file. Instructions to create it from a hex file are included. The
bootloader can as well be activated with the touch 1200 option of nrfutil.
The script download_ble_stack.sh has been adapted to get the version 7.3.0
soft device files. It may have to be executed once before building.
The file system is set to 256k and the pin definitions are adapted.
Besides that, it has the common functionality and omissions. The on-board
sensors and additional flash can be supported by Python scripts.
robert-hh