Arduino UNO R4 Minima and WiFi boards launched for $20 and $27.50

Arduino UNO R4 Minima and WiFi boards powered by a Renesas RA4M1 32-bit Arm Cortex-M4F microcontroller and equipped with an optional ESP32-S3 WiFI & BLE module are now available for respectively $20 (18 Euros) and $27.50 (25 Euros) on the Arduino store.

The Arduino UNO R4 Renesas RA4M1 board was initially unveiled during Arduino Day with most details, but not everything as the company had hidden one part of the board which we now know is for a 12×8 LED matrix and a Qwiic connector for expansion present on the UNO R4 WiFi only.

Arduino UNO R4 specifications:

Microcontroller – Renesas RA4M1 Arm Cortex-M4F MCU @ 48 MHz with 32KB SRAM, 256KB flash
Wireless (Arduino UNO R4 WiFi only) – ESP32-S3-MINI-1 module based on ESP32-S3 dual-core Xtensa LX7 microcontroller with 512KB SRAM, 384KB ROM, WiFi 4 and Bluetooth 5.0 connectivity, PCB antenna
Display (UNO R4 WiFi only) – 12×8 LED matrix
USB – 1 x USB Type-C port for power and programming
Expansions
- Arduino UNO headers with Pins
  - 14x digital I/Os
  - 13x LED pins
  - Analog – 6x analog input pin, 12-bit analog DAC
  - 6x PWM
  - 1x UART, 1x I2C, 1x SPI
  - CAN Bus support
  - I/O Voltage – 5V
  - DC Current per I/O pin – 8 mA
- Arduino UNO R4 WiFi only
  - Qwiic I2C connector for expansion modules.
  - 3-pin header with an “OFF” pin to turn off the board and a “VRTC” pin to keep the internal Real-Time Clock powered and running.
Debugging and programming – 6-pin ICSP header; Arduino UNO R4 Minima only: 10-pin SWD header
Misc – Reset button, Power LED
Input voltage – 6 to 24V via a power barrel jack or Vin, 5V via USB-C port
Dimensions – 68.6 x 53.4mm

Arduino UNO R4 MINIMA — Arduino UNO R4 Minima

Both Arduino UNO R4 boards retain hardware compatibility with the UNO form factor and 5V operating voltage meaning you can keep using existing shields. They also add HID support to emulate a mouse and/or keyboard, and the WiFi model also implements an error-catching mechanism that detects runtime crashes – such as a division by zero – and provides detailed explanations and hints about the code line causing the crash.

Arduino has already been ported to the Renesas RA4M1 microcontroller, and you’ll find detailed hardware and software documentation and example projects for both the Arduino UNO R4 WiFi and Minima on the documentation website, including for the use of new features such as WiFi and USB HID.

Arduino UNO R4 WiFi pinout — Arduino UNO R4 WiFi board pinout diagram

Jean-Luc Aufranc (CNXSoft)

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.