.. _arduino_uno_r4:

Arduino UNO R4
##############

Overview
********

The Arduino UNO R4 Minima/WiFi is a development board featuring the Renesas RA4M1 SoC
in the Arduino form factor and is compatible with traditional Arduino.

Hardware
********

- Renesas RA4MA1 Processor (ARM Cortex-M4 at 48 MHz)
- 256 KiB flash memory and 32 KiB of RAM
- One user LEDs
- One reset button
- One WiFi Transceiver (Arduino UNO R4 WiFi only)
- One 12x8 LED Matrix (Arduino UNO R4 WiFi only)
- Built-in CMSIS-DAP debug adapter (Arduino UNO R4 WiFi only)

Supported Features
==================

The Arduino UNO R4 Minima/Wifi  board configuration supports the following
hardware features:

+-----------+------------+------------------------------------------+
| Interface | Controller | Driver/Component                         |
+===========+============+==========================================+
| GPIO      | on-chip    | I/O ports                                |
+-----------+------------+------------------------------------------+
| UART      | on-chip    | Serial ports                             |
+-----------+------------+------------------------------------------+

Programming and debugging
*************************

Debug adapter
=============

A debug adapter is required to flash and debug programs.
Arduino UNO R4 WiFi has a built-in debug adapter that
you can use for flashing and debugging.

In the Arduino UNO R4 Minima case, You need to prepare
debug adapter separately. A 5V-compatible CMSIS-DAP adapter
adapts to this board.


Building & Flashing
===================

You can build and flash with ``west flash`` command (See
:ref:`build_an_application` and
:ref:`application_run` for more details).

Here is an example for building and flashing the :zephyr:code-sample:`blinky` application.

.. zephyr-app-commands::
   :zephyr-app: samples/basic/blinky
   :board: arduino_uno_r4_minima
   :goals: build flash

.. zephyr-app-commands::
   :zephyr-app: samples/basic/blinky
   :board: arduino_uno_r4_wifi
   :goals: build flash

Debugging
=========

Debugging can be done with ``west debug`` command.
The following command is debugging the :zephyr:code-sample:`blinky` application.
Also, see the instructions specific to the debug server that you use.

.. zephyr-app-commands::
   :zephyr-app: samples/basic/blinky
   :board: arduino_uno_r4_minima
   :maybe-skip-config:
   :goals: debug

.. zephyr-app-commands::
   :zephyr-app: samples/basic/blinky
   :board: arduino_uno_r4_wifi
   :maybe-skip-config:
   :goals: debug


Using pyOCD
-----------

Various debug adapters, including cmsis-dap probes, can debug the Arduino UNO R4 with pyOCD.
The default configuration uses the pyOCD for debugging.
You must install CMSIS-Pack when flashing or debugging Arduino UNO R4 Minima with pyOCD.
If not installed yet, execute the following command to install CMSIS-Pack for Arduino UNO R4.

.. code-block:: console

   pyocd pack install r7fa4m1ab


Restoring Arduino Bootloader
============================

If you corrupt the Arduino bootloader, you can restore it with the following command.

.. code-block:: console

   wget https://raw.githubusercontent.com/arduino/ArduinoCore-renesas/main/bootloaders/UNO_R4/dfu_minima.hex
   pyocd flash -e sector -a 0x0 -t r7fa4m1ab dfu_minima.hex

.. code-block:: console

   wget https://raw.githubusercontent.com/arduino/ArduinoCore-renesas/main/bootloaders/UNO_R4/dfu_wifi.hex
   pyocd flash -e sector -a 0x0 -t r7fa4m1ab dfu_wifi.hex