The Arduino UNO R4 WiFi is the latest evolution of the iconic UNO series, powered by the Renesas RA4M1 (Arm Cortex-M4) processor running at 48 MHz — a 3× speed increase over the UNO R3. With 256 KB flash, 32 KB SRAM, USB-C, and built-in Wi-Fi/Bluetooth via an ESP32-S3 module, it's a major upgrade while maintaining full compatibility with existing UNO shields and the 5V ecosystem.

New onboard peripherals include a 12-bit DAC, CAN bus, op-amp, Qwiic I2C connector, and a 12×8 red LED matrix for animations and sensor data display. The board supports HID emulation, battery-powered RTC, and input voltages up to 24V for direct integration with motors and LED strips.

Key Features

• Renesas RA4M1 Processor – Arm Cortex-M4 at 48 MHz, 3× faster than UNO R3
• Wi-Fi & Bluetooth – ESP32-S3 module for wireless connectivity and Arduino IoT Cloud
• 12×8 LED Matrix – 96 red LEDs for animations, status displays, and sensor plots
• 256 KB Flash / 32 KB SRAM – 8× more flash and 16× more RAM than UNO R3
• USB-C – Modern connector with HID support (mouse/keyboard emulation)
• 24V Input Tolerance – Direct integration with motors, LED strips, and actuators
• 12-Bit DAC – Analog output for audio and waveform generation
• CAN Bus – Industrial communication with minimal wiring
• Qwiic Connector – Easy I2C connection to the Qwiic sensor ecosystem
• Battery-Powered RTC – VRTC pin keeps the real-time clock running when the board is off
• Runtime Error Diagnostics – Detects crashes and provides line-level debugging hints
• UNO Form Factor – Same pinout and shield compatibility as UNO R3

Specifications

• MCU – Renesas RA4M1 (Arm Cortex-M4)
• Clock Speed – 48 MHz
• Flash – 256 KB
• SRAM – 32 KB
• Operating Voltage – 5V
• Input Voltage – 6–24V
• Wi-Fi / BLE – ESP32-S3-MINI
• Digital I/O – 14 (6 PWM)
• Analog Inputs – 6 (ADC)
• DAC – 1 (12-bit)
• SPI – 1
• I2C – 2
• CAN – 1
• LED Matrix – 12 × 8 (96 red LEDs)
• USB – Type-C

Ideal For

• IoT projects with Arduino IoT Cloud integration
• Upgrading existing UNO R3-based projects
• Prototyping with wireless connectivity
• Education and learning embedded programming

Package Contents

• 1× Arduino UNO R4 WiFi Development Board