I'm thinking of using Teensey 4.1 with Zephyr.
After I ordered a few Teensy, I found out there is no SWD or JTAG connection for my trusty Segger J-Link!
Debugging is mentioned here: https://docs.zephyrproject.org/latest/boards/arm/teensy4/doc/index.html
Unfortunately the page doesn't explain what kind of debugging is supported.

Does the Zephyr toolchain support including a GD stub so GDB can be used over serial port?
How does one debug a Teensey application and Zephyr?

Thanks!
Best Regards, Dave

-- 
Dave Nadler, USA East Coast voice (978) 263-0097, drn@..., Skype 
 Dave.Nadler1