SparkFun Arduino UNO R4 WiFi Qwiic Kit Hookup Guide

Contributors: Ell C
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The Arduino Uno R4 Wifi Board

This board is jam packed with functionality. We'll cover some of the basics here, but to read about the full shebang, refer to the Product Reference Manual.


The Arduino UNO R4 board is equipped with a powerful RA4M1 series 32-bit microcontroller from Renesas, which offers increased processing power, memory, and on-board peripherals. Importantly, these enhancements do not compromise compatibility with existing shields and accessories, nor do they require any changes to the standard form factor or 5V operating voltage.

The Renesas microcontroller is highlighted

ESP32-S3-MINI CoProcessor

The UNO R4 WiFi features an ESP32-S3-MINI coprocessor that enhances the capabilities of the RA4M1 microcontroller. With WiFi and Bluetooth connectivity, this board allows makers to easily connect to the internet and create IoT projects.

The ESP32 CoProcessor is highlighted here


You can provide power via the USB-C connector or the Barrel Jack. A USB-C cable is included in the kit, the Barrel Jack can be purchased separately. The RA4M1's operating voltage is fixed at 5 V, whereas the ESP32-S3 module is 3.3 V. Communication between these two MCUs are performed via a logic level translator (TXB0108DQSR).

Both the barrel jack and the USBC are highlighted

LED Matrix

The UNO R4 WiFi includes a bright 12x8 red LED matrix (96 dots total). This feature is ideal for creative projects using animations or for plotting sensor data, without the need for any additional hardware.

The LED Matrix is highlighted

Qwiic Connector

The UNO R4 WiFi includes an industry-standard Qwiic I2C connector that facilitates quick prototyping. With a wide variety of compatible modules that can be connected over I2C, makers can easily create custom projects and expand the capabilities of the UNO R4 WiFi.

The Qwiic connector is highlighted


The board features 14 digital I/O ports, 6 analog channels, dedicated pins for I2C, SPI and UART connections. The pins on either side of the board are highlighted here.

The GPIO pins are highlighted on either swide of the board

Their functionality is shown below; for more details, refer to the Product Reference Manual.

Pinout definitions

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