Arduino Uno R4 WiFi (RA4M1 ARM Cortex M4 + ESP32-S3)

Arduino Uno R4 WIFI, the connected prototyping board for makers

It's been a long time since we had the opportunity to talk about the Arduino range and guess what, the Arduino UNO R4 is here!

This product is the Arduino UNO R4 WIFI, an Arduino R4 Minima with WIFI + Bluetooth as well!
The gain in power is impressive thanks to the Renesas ARM 32 bit 48Mhz Cortex (technical sheet). The UNO R4 works in 5V logic by offering 8x more Flash (256 KiB), 16x more RAM (32 KiB) and 8x more EEPROM (8 KiB of Data Flash) and many other improvements that you can discover here.

The WiFi connectivity is provided by an ESP32-S3-Mini-1 (384Kio ROM, 512 Kio SRAM, 2Mio PSRam, 16 Kio SRAM RTC, and up to 8 Mio Quad SPI Flash). Not only does the ESP32 provide WiFI & Bluetooth 5, BLE and Mesh (Bluetooth Mesh Network) connectivity, but it can also provide many online services.

Combined with Arduino IoT cloud (cloud.arduino.cc), it is possible to visualize data and control projects remotely. As example, IoT cloud allows to append an Alexa voice control to an Arduino project (more info here).

The 12x8 LED matrix is a great idea for displaying text, graph or evolution graph information using a CharliePlexing controller. It will be convenient to display the IP address of the WiFi connection.
Arduino had the excellent idea of creating the matrix with 8 pixels height, just enough to display letters correctly (like in retro computing).

Le connecteur Qwiic présent sur la carte permet de brancher très facilement des cartes/breakout/capteurs supportant cette connectique 4 fils (3.3V, GND, SDA, I2C). Qwiic transporte un bus I2C, il est donc très facile de chaîner les capteurs/actuateur sur un seul bus.
Qwiic est une norme inventée par SparkFun USA également supportée par Adafruit Industries sous le nom StemmaQt. Nous proposons également des câbles Qwiic/StemmaQT/JstSH-4 sur notre shop.

The Qwiic connector present on the board makes it very easy to connect expansion/breakouts/sensors supporting this 4-wire I2C connection (3.3V, GND, SDA, SCL). As this connector carry an I2C bus, it is very easy to chain the sensors/actuator on a single bus.
Qwiic is a standard invented by SparkFun USA also supported by Adafruit Industries (under the name StemmaQt). Our shop also offers Qwiic/StemmaQT/JstSH-4 cables.

The Uno R4 WiFi still features:

• 14 digital I/O
• 9 analog input
• 6 PWM output
• 1 analog output (DAC)
• 4 UART
• 1 SPI bus
• 1 I2C bus
• 1 CAN bus

Technical details

• Size (maximum): 75.14 x 53.51 x 15.08mm
• Weight: 27.95 gr
• Logic: 5V
• Supply: up to 24V!
• Microcontroler: Renesas RA4M1 (datasheet)
  - 256 Kio Flash (32 Kio for the R3)
  - 32 Kio SRAM (2 Kio for the R3)
  - 8 Kio Data Flash (data storage like EEPROM does)
  - Analog/Digital converter (A/D) of 14 bits
  - Natif USB 2.0 with HID support (keyboard/mouse)
  Hardware - SPI / I2C
  - SCI ( UART / simple SPI / simple I2C )
  - CAN 2.0B support (High speed industrial bus)
  - Tactile input (Capacitive Touch Unit)
  - LCD controler (requires some additional research in the datasheet)
  - Analog output on 12bits (and some other at 8 bits as stated in the datasheet)
• ESP32-S3-Mini-1 for the WiFI/Bluetooth/Arduino Cloud I/O connectivity
• 8x12 LED matrix display
• Digital I/O: 14 (6 of them with PWM)
• Analog Input: 6
• Max current par I/O: 8 mA
• Clock speed: 48 MHz
• Révision R4

Advanced features offered by the microcontroller

• As it is a Cortex-M4 core, the MCU does have a floating point calculation unit (FPU) and DSP instructions (signal treatment).
• A unique identifiant over 128 bits.
• A audio interface SSIE : Serial Sound Interface Enhanced
• WatchDog : qui redémarre le MCU en cas de plantage
• 4 Op-Amp (see analog section of the datasheet)
• TSN temperature calulation (see analog section of the datasheet)
• RTC clock with external battery support.
• Sleep mode
• Random number generator TRNG
• Hash calculation (GHash)
• AES encryption 128/256

Datasheet: Uno R4 WIFI (Arduino.cc)