Who has yet tried the new flagship R4?
A third of the forum is filled with messages dedicated to R4 - and you ask if anyone has tried this controller?
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@den1willemoes There's a subforum dedicated to discussion of the R4, you might get more traction (and less guff) there.
Scroll through the forum to read about all the problems people have encountered. Better, use the forum search box!
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I moved your topic to a more appropriate forum category @den1willemoes.
In the future, please take the time to pick the forum category that best suits the subject of your question. There is an "About the _____ category" topic at the top of each category that explains its purpose.
Thanks in advance for your cooperation.
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Indeed.
And not only this forum - loads of people are posting reviews, videos, etc all over the interwebs...
@den1willemoes - Was there something specific you wanted to ask about it (or, rather, them) ?
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I've been playing around with the minima and here are a few impressions
I've been pleasantly surprised with the accuracy of the ADC
Here is a measurement from my precision reference (which is 2.048V). With a little oversampling and filtering it's rock solid and quite accurate(ideally would read 2048)
There has also been some cool discussions on the forum about how fast you can write to pins and make analog measurements. @susan-parker has done some cool stuff here.
Having a DAC is a lot of fun! it also appears to be quite accurate but no data to show here.
the floating point support is great so my DSP runs lightning fast
But there are problems. The main one is that it is new and not so fantastically supported yet. For a some features, you'll have to read the datasheet and implement them yourself.
But ultimately I think it's quite a promising board.
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Hi, lovely graph!
Is this with USB power or with an external input that gets the internal board DC/DC ?
On my R4 board I get the nominal +5V at something like +4.72V when VUSB powered (due to D3 the Schottky reverse protection diode for when the internal DC/DC is running).
If I attach external power the ADC reading changes and gets a lot more noisy.
Thanks for the mention 
USB, still get a bit of noise at 50Hz but I've used a 4th-order digital filter with a 5Hz cutoff so even this gets removed for very clean DC signals.
that's a pain. I haven't powered externally yet
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R4 ADC Tests: Note these are "raw" readings without any averaging or other filtering.
14bit ADC, with USB power:
14bit ADC, with external power i.e. DC/DC converter running:
Just on my workbench, not a "tidy" measurement.
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Don't forget "complaints"!
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Added how to setup and use the DAC... it took a bit of time to get going.
Note the DAC uses separate external Aref pins to the ADC, so the external Aref option is not available.
https://github.com/TriodeGirl/Arduino-UNO-R4-code-DAC-ADC-Ints-Fast_Pins
I am thinking to purchase it but what is the major difference between R3 and R4 version?
The R4 has a completely different chip that has never been used for an Arduino board before. A 32bit ARM CM4 from Renesas: the RA4m1.
This has significantly more code and data memory, hardware floating point support, runs at 48MHz, and has native USB support. In theory, it should be significantly faster than an Uno R3, but so far several common features (like SPI) have turned out to be slower 
The power supply section is also improved.
It's Uno-compatible in the sense that IO is 5V, and the high-level pin assignments are the same (eg A4 and A5 duplicate the I2C pins, so there are exactly 20 available IO. (Which IMO is sorta sad for a 64pin chip!)) But many things are not nearly as Uno-compatible as the name would imply, and I think it was a mistake to label it this way.
There are weird things in the core code, which is built on top of the Renesas "Flexible Software Package" (FSP) libraries. FSP seems to have some of the same problems as many vendor-provided libraries
There are weird things in the hardware (like needing to map 100+ peripheral events onto 32 interrupts.) There are things that are not documented. I do not like the documentation very much. The Minima and Wifi boards are more different than you would expect.
Renesas is not known for being "hobbyist-friendly", but they have invested significantly in Arduino, so perhaps they are trying to change. I do not see a healthy Renesas user forum akin to avrfreaks (but then the ARM forums from ARM are also pretty awful.)
The most significant part may be the hint that Arduino and Microchip have had some sort of falling out. (I don't think there has been an Arduino product using a Microchip part that was introduced since the Atmel acquisition...)
We shall see.
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What about the Nano Every with the ATmega4809.
Unfortunately the naming of the R4 as a Uno based on the form factor is similar to the naming of the Every as a Nano. In my opinion this naming has led to much confusion with beginning users, and it will likely be replicated with the R4.
I think the 4809 was introduced just before the acquisition, along with some of the tiny0/1 series. The "after" chips include the AVR-Dx, AVR-Ex, and PIC32C...
The Atmel acquisition was in 2016. I believe the SAMD21 came out after that point (Arduino Zero, Nano 33 IoT, and the MKR family). And the ATmega4809 (Arduino UNO WiFi Rev 2 and Nano Every) also came out after 2016.
I also hate the board naming and the attempt to shoehorn all the modern microcontrollers to be compatible to the ancient ATmega328P.
What I find interesting about the R4 is not the R4 itself but the high proportion of questions from "new" forum members, but otherwise seemingly experienced users, who appear to have got hold of one.
I think I'll resist the temptation to get one at the moment. Having found my way around the AVR (including tinyAVR and megaAVR) data sheets and partly around those of the ESP8266, ESP32, STM32 (bluepill) with their respective abstraction layers, I'm reluctant to get involved with a whole new platform. For a similar reason I have also resisted getting hold of one of the much talked about NXP based Teensys.
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I think I gave into temptation because it can do a number of things quite well that other boards specialize in.
- It has both wifi and good analog input/output which the ESP32 does not(quite nonlinear)
- it's not as fast as the latest teensy but I just ran 32 floating point 4th order IIR filters at 48000 Hz this morning (not bad).
- it's got a very nice power supply section as mentioned by @westfw
- native USB, hopefully will support USB audio class (as Arduino MBED does)
- at some point it may offer on-board debugging via the ESP32 without extra hardware. This would be both useful and a wonderful educational tool for those who have no experience of embedded debugging.
- It is within the ARM ecosystem which is already familiar to some.
- it is an arduino, so you are supporting a pretty damn good cause.
do any of these points tempt you yet @6v6gt?
obvs, I'm leaving out the major downside that it doesn't have the community support that really makes the r3 a powerhouse.
Yeah, i bought my R4 Wifi with a 3.5" Display Shield (ILI9486) which would be a strong combination to visualize some data but gave up modifying the given library source code because it fails to compile every given example for the R4. I am just not that into C++ to modify a library to support another plattform.
I hope these problems will get sorted out