One of the most popular microcontroller boards, the Arduino Uno was launched in 2010 and the Uno R3 (Revision 3) has been the standard for over a decade.yesterday was big news Arduino Day Live Stream (opens in new tab)The company announced the upcoming Arduino Uno R4 board. This will be a huge leap in processing power, RAM, storage and connectivity.
The Arduino Uno R4 will be available in May and will come in both a “Minima” (regular) and Wi-Fi version, though pricing has not yet been announced. The wireless version features an Espressif S3 module that supports both Wi-Fi and Bluetooth connectivity.
The Uno R4 keeps the same pinout and layout as its predecessor, but steps up to the 32-bit Renesas RA4M1 CPU running at 48 MHz. This is a significant upgrade from his 8-bit, 16 MHz ATmega328P processor in his previous Unos. The new chip is based on the Arm Cortex M4 architecture as opposed to his AVR RISC-based platform of previous processors. Arduino says most existing software libraries should work without modification, but some optimized for the AVR may need tweaking.
The Uno R4 has 32K of SRAM, which is 16 times more than the Uno R3’s 2K. It will also have 256K of onboard NAND as opposed to 32K on R3. Instead of the cumbersome USB Type-B port on older models, there’s a USB-C port for connecting your PC. The barrel power connector is still there, but now it can handle up to 24V instead of 20V. It also has a 12-bit analog DAC, CAN bus and SPI port.
| Header Cell – Column 0 | Uno R4 | Uno R3 |
|---|---|---|
| CPU | Renesas RA4M1 (48 MHz, Arm Cortex M4) | ATmega328P (16MHz, AVR) |
| SRAM | 32K | 2K |
| flash storage | 256K | 32K |
| USB | type C | type B |
| Maximum voltage | 24V | 20V |
In the official photo of the Uno R4 (shown at the top of this article), Arduino has placed yellow and green boxes on part of the PCB. In that broadcast, the company said it would keep the surprise factor and not reveal what’s under the box until closer to launch.
If you want to buy the Uno R4 early, waiting list (opens in new tab) Be notified when your board is on sale.there is also early adopter program (opens in new tab) For developers who have created popular libraries. If you are accepted into the program, the company will send you a free Uno R4.
We don’t know the price of the Uno R4, but given the current price of the Uno R3, it’s safe to assume that the Minima version will cost $25 and up. The Uno R4 WiFi is clearly expensive.
The new Uno R4 should be a boon to manufacturers currently building robots and iOT devices with Arduino. Compatible with a huge ecosystem of shields and other accessories for better performance.
However, the Uno R4 faces very stiff competition from boards based on the Raspberry Pi’s RP2040 chip. The RP2040 runs at a generous 133 MHz (about 3x the Uno R4) with dual cores and 256K of SRAM. There are many boards with the RP2040, but the first party Raspberry Pi Pico is just $4 for the base model and $6 for Wi-Fi/Bluetooth.
On the other hand, the Uno R4 can handle much more power than the RP2040 board. Because its power connector supports up to 24V instead of just 5V on the Raspberry Pi platform. There is a detailed comparison between the previous generation Arduino and the Raspberry Pi Pico. I will update as soon as I get the R4.
