Problems with the ATSAMD21G18-AU


I am designing a PCB with several sensors using the ATSAMD21G18-AU, but I am having problems with burning the bootloader  using a JTAGICE3 (also tried the SWD PCB version).

Atmel Studio gives me the error message "No device detected. Error 4109", but it does read the correct voltage.

I've tried to measure over XIN/XOUT and there is no oscillation there. Could this be the issue? I tried to hook XIN32 up with a signal generator, but still the same error message.

Any helpful tips?

I have an open case at microchip regarding the issue, but their response time is really slow.

Attaching the schematic:


More questions in this forum