Arduino Uno R4 Review - Best Arduino Board Ever?

The latest iteration of the Arduino Uno is out, the Arduino Uno R4. As the successor to the Uno R3, the new board uses a 32-bit Arm Cortex-M4 CPU alongside an ESP32-S3 which provides Wi-Fi and Bluetooth connectivity. Add USB-C, a 12-bit DAC, and a 12x8 LED matrix then this just might be the best Arduino ever!
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#garyexplains

[ergindemir]

This R4 wifi board is probably the best value Arduino board ever made. Most interesting part is the led matrix, they use charlieplexing instead of regular led driver ic, less bright and efficient but save a lot of cost.

[rickh]

I bought one of each here in the U.S. and the shipping was $3.50, no sales tax. I try to buy all of their new boards to support the ecosystem.

[johnking]

Its a tough piece of gear. Idiot delivery man threw the package over my back fence and, since I didn't know it had been delivered it was out in the rain for 3 days. The cardboard was sodden so I dried it as best I could and left it on a warm shelf for 2 days. It works fine!

[anugrahandi]

Some people asked why not just skip the UNO and going with Arduino Nano, or ESP 32, or other boards. Well, at least for me, it suits well: 5V connectors so it would still be compatible with my sensors, also now come with ADC so I don't need additional controller to control my actuator (needs 1-5V DC signal for control input), and also now it comes with neat LED to show any error or status for fast debugging. All in one 'package' that robust and easy for my project.

[Stabby]

Weirdly the WiFi module is a lot more powerful than the ARM part 😁 I always wonder why they choose to do this - maybe just the number of I/Os.

[warrenscorner]

I was so disappointed when I discovered that my Arduino Uno WiFi rev2 board wouldn’t connect to the Arduino Cloud. I’m really looking forward to playing around with this one. I actually like that it doesn’t take up space on my breadboard.

[PeetHobby]

What is the "best" Arduino always depends on your use case. 😊

[sagerdood]

Not big enough for me
I use megas only

[rambo]

Wouldn’t a downside be that some some existing libraries or projects might need to be updated to work on this rev?

[rogercarlsson]

I don't really understand what the LED matrix could be used for. Seems to be a gimmick.

[redikaak]

So basically this is just like connecting the ESP32-S3 to an Arduino R3 with improvements in the processor sector

[petermainwaringsx]

Shame there is no antenna socket on the WiFi.

[Bob_Burton]

Incompatibility with many existing libraries is a big problem at the moment judging by the posts on the Arduino forum. This will improve in time but right now is a big problem

[whothefoxcares]

Q: Can the Arduino Uno R4 be used to build a #TRUTH detector to regulate who uses which washroom?👍

[gedtoon]

Do you have any information on why the SPI bus is so slow on the Uno R4?

[donkeypoopdragon]

My problem with the uno is its so big! After using a seeeduino xiao, every other board seems way too big

[steveu]

The popular GRBL cnc controller can not be flashed to Arduino4 do you think it will be long before it can be used for GRBL?

[QuimChaos]

29.99/19.99€ R4 WiFi/Minima in Portugal @Mauser...

[viktorhugo]

If you have a ESP32-S3 on the board why you will program the ARM with M4 Core?

[stark_energy]

With current price of Arduino R4 it is way too expensive for this low-spec. You can get several ESP32 from the same price. And ESP32 still has some winning category such as faster processor speed, higher memory, smaller form factor and more pins. It is only great when the price of Arduino R4 down to near the same as ESP32. And no, I don't need that built-in LED matrix. It is better to buy LED Matrix module separately (if needed) than to burden the buyer with this cost.

And there are tons of microprocessors (small Computer) like Orange Pi that is just double or triple the price of this Arduino but way far far more powerful (like GHz of multi-core processors and Gigabytes or RAM with Linux OS and HDMI display support). I know this is not apple to apple comparison as Orange Pi is already on different league with Arduino but hey, the price matters a lot. You don't pay for expensive things for Arduino. It supposedly not to be expensive, otherwise it enters different market, the market of complex microprocessors. In my country, I check that with the same price, I could buy second-hand Orange Pi Zero LTS with 512MB and 1.2GHz Quad Core + Wifi + USB + Audio and Ethernet socket.