J-Link 19-pin Cortex-M Adapter
The SEGGER J-Link 19-pin Cortex-M Adapter allows JTAG, SWD and SWO connections between SEGGER J-Link debugger and Cortex-M based target hardware systems. It adapts from the 20-pin 0.1'' JTAG connector to a 19-pin 0.05'' Samtec FTSH connector as defined by ARM.
Overview
The J-Link 19-pin Cortex-M Adapter may also be used to connect J-Link to a non Cortex-M target as far as the target connector uses the same pinout as shown below.
By default, TRST is not connected, but the Cortex-M Adapter comes with a solder bridge (NR1) which allows TRST to be connected to pin 9 of the Cortex-M adapter.
SEGGER J-Link debuggers are the most popular choice for optimizing the debugging and flash programming experience.
Documentation
Debugging with the Arduino IDE 2.0
Learn how to set up a Zero board, J-Link and Atmel-ICE debuggers with the Arduino IDE 2.0, and how to debug a program.
Using the Segger J-Link debugger with the MKR boards
Learn how to set up a MKR board with the Segger J-link debugger.