I want to modify SAM BA bootloader for SAM D21 and adapt it for my project. My target device is ATSAMD21J18A and I would use USB CDC for bootloading.
Now when I program my ATSAMD21J18A and connect it to computer, I get an "UNKNOWN DEVICE" error.
But at the same time if I program ATSAMD21J18A with pre-compiled binary files (which came along with source code zip file) then it works absolutely fine.
How can I solve it?
please help me~