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
Building an Application and
Run an Application for more details).
Here is an example for building and flashing the Blinky application.
# From the root of the zephyr repository
west build -b arduino_uno_r4_minima samples/basic/blinky
west flash
# From the root of the zephyr repository
west build -b arduino_uno_r4_wifi samples/basic/blinky
west flash
Debugging
Debugging can be done with west debug command.
The following command is debugging the Blinky application.
Also, see the instructions specific to the debug server that you use.
# From the root of the zephyr repository
west build -b arduino_uno_r4_minima samples/basic/blinky
west debug
# From the root of the zephyr repository
west build -b arduino_uno_r4_wifi samples/basic/blinky
west 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.
pyocd pack install r7fa4m1ab
Restoring Arduino Bootloader
If you corrupt the Arduino bootloader, you can restore it with the following command.
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
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