boards: arduino_nano_33_ble: add pyocd support

Add support to debugging and flashing with the pyocd.

Signed-off-by: TOKITA Hiroshi <tokita.hiroshi@fujitsu.com>

boards/arm/arduino_nano_33_ble/board.cmake

@@ -1,4 +1,7 @@
 # SPDX-License-Identifier: Apache-2.0
 
+board_runner_args(pyocd "--target=nrf52840" "--frequency=4000000")
+
 include(${ZEPHYR_BASE}/boards/common/bossac.board.cmake)
+include(${ZEPHYR_BASE}/boards/common/pyocd.board.cmake)
 include(${ZEPHYR_BASE}/boards/common/blackmagicprobe.board.cmake)

boards/arm/arduino_nano_33_ble/doc/index.rst

@@ -121,6 +121,30 @@ Then, you can flash the image using the above script.
 
 You should see the the red LED blink.
 
+Debugging
+=========
+
+You can debug an application on the board with a debug adapter that supports
+CMSIS-DAP. This board has the SWD connector for debugging but exposes it as
+a test pad pattern (not a connector) on the back side of the PCB. So, It needs
+bit of difficult soldering. At a minimum, SWDIO and SWCLK need soldering (As
+shown in the picture). GND, 3.3V, and RESET are also available in the DIP
+connector, therefore it may be easier to connect using the DIP connector
+instead of soldering to them.
+
+.. image:: img/nano_33_ble_swd.jpg
+     :align: center
+     :alt: Nano 33 BLE SWD connecting
+
+After connecting the debug adapter, you can debug it the usual way.
+Type the following command will start debugging.
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/basic/blinky
+   :board: arduino_nano_33_ble
+   :maybe-skip-config:
+   :goals: debug
+
 References
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