Arduino Uno R4 Minima (RA4M1 ARM Cortex M4 - assembled)

Arduino Uno R4 Minima, the new 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!

It is an Super-powered Arduino propeled by a 32 bit ARM Cortex at 48Mhz, the Renesas Renesas RA4M1 (fiche technique).
Like its predecessors, the UNO R4 operates in 5V logic! Which seems essential to us for Arduino UNO range.

The Uno R4 is avialble in two flavors:

• R4 Minima : an Arduino UNO on steroïds. A fabulous jump in power for our maker project!
• R4 WiFi : available here with Steroïds + WiFi connectivity + 12x8 LED Matrix !!!

So the UNO R4 offers 8x more Flash (256 KiB, program storage), 16x more RAM (32 KiB) and 8x more EEPROM (8 KiB Data Flash). The analog inputs are more precise (up to 14 bits instead of 10 bits) and the R4 has an analog output.

The R4 also gives pride of place to encryption tools (RSA, AES, HASH, Unique ID) and signal processing (DSP). The RA4M1 also offers 4 operational amplifiers, an SSIE (Serial Sound Interface Enhanced) audio output and other features.

A big improvement of the R4 is the availability of several serial ports (UART to be precise).
As the Arduino R3 (ATMega328) was limited to a single UART, it was impossible to use the serial console to debug while receiving GPS data (which also uses a serial port).
On the Arduino R4, it will now be possible to receive serial data while using the serial console. This will really change the makers live for many projects.

The Uno R4 Minima offers:

• 14 digital I/O
• 9 analog inputs
• 6 PWM output
• 1 analog output (DAC)

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)
• Digital I/O: 14 (6 of them with PWM)
• Analog Input: 6
• Max current par I/O: ? 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 Minima (Arduino.cc)