UNO R4 WiFi

The Arduino UNO R4 WiFi is designed around the 32-bit microcontroller RA4M1 from Renesas while also featuring a ESP32 module for Wi-Fi® and Bluetooth® connectivity. Its distinctive 12x8 LED matrix makes it possible to prototype visuals directly on the board, and with a Qwiic connector, you can create projects plug-and-play style.

GET STARTED

DATASHEET

Main Features

The MCU on the board is the high performance Renesas RA4M1 (Arm® Cortex®-M4) with a 48 MHz clock speed, 32 kB SRAM and 256 kB flash memory. This MCU features an RTC, a DAC and a CAN bus and has support for HID via USB.

The UNO R4 WiFi also features an ESP32-S3 for Wi-Fi®/Bluetooth® connectivity, which can also be separately programmed via a specific header.

Cheat Sheet

A reference to all technical features on this board, with pointers to additional documents.

Cheat Sheet

5 V Operating Voltage

The RA4M1 and the GPIOs of this board operates on 5 V.

LED Matrix

Learn how to create animations and graphics on the 12x8 LED matrix.

Documentation

Real-Time Clock (RTC)

Keep track of time & date and set alarms with the built-in RTC.

Documentation

Digital-to-Analog Converter (DAC)

Use the onboard 12-bit DAC to build sophisticated audio projects.

Documentation

Mouse/Keyboard Emulation (HID)

Build game controllers by emulating a mouse/keyboard.

Documentation

Input Voltage

Power your UNO R4 board through the VIN pin or the barrel jack at up to 6-24 V.

Tech Specs

Here you will find the technical specifications for the Arduino® UNO R4 WiFi.

Note on ESP header: the ESP32-S3 module on this board operates on 3.3 V. The ESP header located close to the USB-C® connector is 3.3V only and should not be connected to 5 V. This may damage your board.

Note on Qwiic connector: the Qwiic connector on this board is connected to a secondary I2C bus on this board, IIC0. This connector is 3.3 V only, connecting higher voltages may damage your board. To initialize this bus, use

Wire1.begin()

instead.

Maximum current draw per pin: the UNO R4 series' maximum current draw per GPIO is 8 mA, which is significantly lower than previous versions. Exceeding this limit may damage your pin / board.

Board	Name	Arduino® UNO R4 WiFi
Board	SKU	ABX00087
Microcontroller	Renesas RA4M1 (Arm® Cortex®-M4)
Radio Module	ESP32-S3-MINI-1-N8
USB	USB-C®	Programming Port
Pins	Digital I/O Pins	14
	Analog input pins	6
	DAC	1
	PWM pins	6
	External interrupts	2,3
Communication	UART	Yes, 1x
	I2C	Yes, 1x
	SPI	Yes, 1x
	CAN	Yes 1 CAN Bus
Power	Circuit operating voltage	5 V (ESP32-S3 is 3.3 V)
	Input voltage (VIN)	6-24 V
	DC Current per I/O Pin	8 mA
Clock speed	RA4M1	48 MHz
Clock speed	ESP32-S3-MINI-1-N8	up to 240 MHz
Memory	RA4M1	256 kB Flash, 32 kB RAM
Memory	ESP32-S3-MINI-1-N8	384 kB ROM, 512 kB SRAM
Dimensions	Width	68.85 mm
Dimensions	Length	53.34 mm

Compatibility

Essentials

First Steps

Quickstart Guide

All you need to know to get started with your new Arduino board.

Suggested Libraries

Wire

This library allows you to communicate with I2C / TWI devices.

SPI

The SPI library allows you to communicate with SPI devices, with the Arduino board as the controller device.

Servo

The Servo library allows an Arduino board to control RC (hobby) servo motors.

Arduino Basics

Built-in Examples

Built-in Examples are sketches included in the Arduino IDE and demonstrate all basic Arduino commands.

Learn

Discover interesting articles, principles and techniques related to the Arduino ecosystem.

Language References

Arduino programming language can be divided in three main parts: functions, values (variables and constants), and structure.

Tutorials

Arduino UNO R4 WiFi ADC Resolution

Learn how to change the ADC resolution on the UNO R4 WiFi.

ADC

14-bit

Arduino UNO R4 WiFi CAN Bus

Learn how to send messages using the CAN bus on the UNO R4 WiFi.

CAN

Arduino UNO R4 WiFi Cheat Sheet

Learn how to set up the Arduino UNO R4 WiFi, the fourth revision of our most popular and important development board.

Installation

I2C

SPI

UART

Wi-Fi

Bluetooth

Arduino UNO R4 WiFi IoT Cloud Setup Guide

A step-by-step guide on how to set up the UNO R4 WiFi with the Arduino IoT Cloud.

UNO R4 WiFi

IoT Cloud

Arduino UNO R4 WiFi Digital-to-Analog Converter (DAC)

Learn how create waveforms and output them on a piezo, using the DAC on the UNO R4 WiFi board.

Waveform Generation

Analog

DAC

Arduino UNO R4 WiFi EEPROM

Learn how to access the EEPROM memory on the UNO R4 WiFi.

RTC

Alarm

UNO R4 WiFi Custom Firmware Upload to ESP32 (Advanced)

Learn how to load custom firmware to the ESP32-S3 module on the UNO R4 WiFi, using the esptool.py command line interface.

ESP32

esptool

Flash

Using the Arduino UNO R4 WiFi LED Matrix

Get off the ground with the Arduino UNO R4 WiFi built-in LED matrix. Learn the different techniques for controlling it, create animations, graphics or even games.

Guide

LED Matrix

Arduino UNO R4 WiFi Qwiic Connector

Learn how use the Qwiic connector on the Arduino UNO R4 WiFi.

Qwiic

STEMMA QT

I2C

Getting Started with UNO R4 WiFi

A step-by-step guide to install the board package needed for the UNO R4 WiFi board.

UNO R4 WiFi

Installation

IDE