Glad to see you here! Thank you for your answers. I will pin your comment that everybody can see it. I was not aware that the clones also have an external interface chip (I did not find a diagram). However, I wondered what this chip between the CH340 and the MPU is... This also answers the question about the "no bootloader". I thought the fuses are "burned" automatically. But this seems not the case. So we always have to press "Burn bootloader" if we change the frequency? Most people here use PlatformIO for debugging. Is there a possibility to debug these ATmega chips with PlatformIO?

​@@AndreasSpiess I'm not sure why the fuse that sets the main system clock (fuse5/SYSCFG0) wasn't automatically set correctly when you're uploading. I have the exact same board, and It happens automatically for me. I'd be very grateful if you took the time to open an issue over at the MegaCoreX repo where you paste the IDE output after tuning on verbose upload in the IDE settings. (Note that a fuse change is only required when switching the main clock. A switch from 16 to 8, 4, 2, or 1 MHz is done in software before setup() ). The chip between the CH340 and the ATmega4808 is very likely a Nuvoton N76E003AQ20 microcontroller that runs a modified version JTAG2UPDI sketch. I don't think a schematic exists for this board, but someone at the Avrfreaks forum figured out the programmer chip part number. I'm a PlatformIO user myself, and I've put a lot of effort into making support for the entire AVR ATmega range as good as possible. Sadly, there's currently no AVR debugging support. A few enthusiasts have been working on it and got close. The discussion can be found here: community.platformio.org/t/debug-an-avr-4809-with-microupdi/19926t However, PlatformIO support for AVRs has gotten very good apart from the debugging part. You can define your preferred hardware settings in platformio.ini, and it will calculate and load the correct fuses (and bootloader if selected) for you. A guide for configuring the platformIO.ini file for megaAVR-0's can be found here: github.com/MCUdude/MegaCoreX/blob/master/PlatformIO.md

Can micropython support the new MCU?

​@@foxeskeeper3817 A python interpreter could theoretically work on an 8-bit microcontroller, but Micropython requires a 32-bit processor such as an ARM or Xtensa based one.

@@hansibull Thanks for the info. Issue created.

I agree. I also used these Pro Minis in my 3.3V projects.

Ennar - would the "fuse" be useful to the beginner? Intermediate? Advanced? Thank you.

@@bob-ny6kn It's a low-level register that changes the startup configuration of the microcontroller, like clock source and frequency. memory protection and undervoltage detection. Beginners usually won't have to worry about it.

And for the "older chips" you needed a special 12V programmer for programming.

@@nrdesign1991 Thank you. I am not there yet. :( But I am having fun at the beginner level, trying to get familiar with the complete syntax. Looking to bake my first ATTINY85 soon. Long term: motorized blinds (RTC and remote control), WS2812B storefront display lighting, and the biggie- Aduino P.O.S.T. shield. I might be at the fuse level after.

You are welcome! This is the task of a UKpostsr ;-)

Glad you enjoyed it!

Glad you enjoyed it

My pleasure!

Well possible. But the time of 5 volt only boards is limited..

Also a good solution. Such a chip runs in my mailbox sensor

@@AndreasSpiess Indeed a good solution, especially when the target application needs a lot of flash memory. PS. Your video about CAN communication will probably be useful to me in a near future!!

You are welcome!

It's my pleasure!

1. I was able to program the clone with the bootloader and UPDI without changes on the board. 2. You are right with the 16/20MHz. As I said, it was strange to me. And your explanation is the solution. I was not aware of that. 3. You are right with the "fast" commands. Still, they are much faster for the casual user and I do not know why they are not available for the standard Arduino. 4. Thank you for the additional info about the differences 5. I only know of the Pro Mini 3.3V board on Aliexpress. Others might be available in different channels.

As for the programming issues, you can make a cheap UPDI programmer with a CH340 IC, or even a self enclosed USB-to-UART cable with some addons. For making circuits with raw ATmega4808 (or any other from the new series) I’d recommend just leaving that 3-pin UPDI header open, and use a custom programmer for it when needed. Much more compact and cheaper than putting a programming chip on every PCB.

So you are trying to tell me that they put a 48MHz 32bit ARM-M0 on a board to act as a programmer for a 8bit micro? Oh well the Atmega range of device have been sort of obsolete due to price/performance ratings for a while now.

@@TalpaDK Well, it's way cheaper than the ATmegaU2 they're using as USB-to-serial converter on the Uno, not to speak of the FT232 on the Nano -- none of which comes with an embedded hardware-level programmer for the AVR. I think it makes a lot of sense for a hobbyist "plug and play" board like this.

You are welcome!

Glad it was helpful!

Thank you!

You are right, you get a reduction with that method. If I remember right you have to pay attention on how low you go if you want to use the peripherals.

99 percent of current measured are due to how the "arduino" and people's code handles things. If you code using the avr libraries, use sleep modes, interrupts, etc the current can be very low. As another point of reference using Adafruit ble type libraries to do a keyboard on an nrf52 results in milliamps. Custom implementation using nrf5sdk 50microamps while ble is working. While ble is inactive and device is sleeping 1microamp. You can do similar with all this stuff it's just hobbyist code and ide are setup for easy, not energy efficient programming. Superloops for checking pins and delays is like running a chip flat out onwith the processor busy all the time. I've seen coin cell atmega chips that can run a year on a 2032. It's just in the code.

@@kwakeham Do you use the Arduino IDE for programming BLE on the NRF chips? I am interested because this is on my to-do list...

You're welcome

Thank you!

You are welcome!

Thank you!

Thank you!

I mostly use ESP32s here. But as you, sometimes an Arduino is the better choice.

I agree if you only look at the hardware. For a Maker with constraint time, it is also important if he finds libraries and projects to replicate. And there, the past rules the future.

@@AndreasSpiess stm32duino core is stupidly easy and fully (I believe) backwards compatible with original core, so only libraries that won't work are probably the ones that target specific MCUs directly, utilizing low level hardware registers and not via Arduino.h abstraction layer. I used to overestimate the difficulty of switch to STM too, but was surprised how accessible is now. The most limiting factor is MCU prices really (: because you always want more chips.

In my opinion the role of the new AVR chips is simply to beat in price. You really don't need 256kB of flash or 80MHz 32bit CPUs for most projects that require a microcontroller. For prices around 0.4€, you can get yourself MCUs from the Tiny0 family that offer low power consumption and more than decent peripherals (serial communication protocols, RTC, 10-bit ADC much better than on ESPs, 8-bit DAC, Event Controller for relieving the CPU from certain tasks, and even capacitive sensing for the higher memory variants). If I want to make a non-iot project that doesn't require huge data processing or pre-made libraries, I'll definitely go for the AVR option, I also find it funnier to program, it's better for low-level people :)

@@rojirrim7298 I get the masochistic appeal of 8-bit chips programmed in assembly code. I used to love programming PIC chips this way. But as soon as you go to C this disappears. The price difference only really applies to chips and is really only important if you are making a low margin device in large quantities. At board level, RP Pico costs less than any official Arduino and most makers will not be producing in high enough quantities for the difference in chip prices (or indeed the chip prices!) to be significant compared to engineering time or even sufficient coffee to sustain the most modest coding effort!

@@john_hind So true. I just got 4x RP2040 for $2.24 each the other day. Atmega4809p is $6.64 and almost gone. STM32F0 from $5.31 STM32F401RCT6 $11.04 STM32F103C8T6 $14.52 Atmega328p is $88 and a week long shipping xD Local trustworthy distributor.

You are welcome!

You are welcome!

You are welcome!

Glad to hear that

Thank you for sharing your experience!

Thank you for sharing your experience!

Thank you for the additional information!

I agree. A lot of my sketches without Wi-Fi are one or two pages long and solve a problem where we used to use a few logic chips.

That why they make atmega48xx or AVRDA with highest performance for 8bit mcu, ofc it still small when compare with arm32bit

"The 8bit Atmel MCU's are obsolete and only useful for tiny applications." // And for the "fat" applications there is an option to use a low powered PC (like RaspberyPi) with the full featured OS.

my opinion: both are great I personally like AVR's because of instant boot times, not requiring a bootloader otherwise i'd use an ESP32 personally because i could use quite a few useful things of it. I made a controller for slot cars that runs on a standard Arduino Nano (flashed with an Uno i've got anyways as ISP to not need the bootloader) because "track calls" kill the power entirely, same thing when doing a lane change (analog, not digital) where you will definitely want it to be able to boot up instantly, the half sec boot time of an ESP will screw you

I agree, Espressif so far had no (visible) shortages. Astonishing! BTW: I agree that we should not compare the 8 bitters with the 32 bitters.

@@AndreasSpiess You ignored, "Couldn't be happier after making the change over and wish I had done it sooner, cheaper and far outperforms the offerings from Atmel." I am not surprised, not a little, not at all. Ignorance is a sanctuary favored by the complacent. Like many older engineers you seem to be steadfastly focused on the past while you purport to be boldly moving out into the future. It's as if you are saying, "The future looks great!... now let me go back to using the inferior tools and technologies I am comfortable using." Perhaps when you extract money from your ERP customers for your current employer, that is a profitable approach. But this channel implicitly claims to focus on presenting technologies that are well-suited for makers, not anachronistic technologies such as ERP or Ham radio which many folks with heads of grey hair have invested many thousands of hours learning. I assert that for the vast majority of projects, which the vast majority of makers create, MicroPython on the ESP32 is superior to competitors in the microcontroller market such as the ATmega4808. As I have opined in a previous comment of mine, you are cobbling together toy projects. For those projects using modifying pre-existing software makes sense. But for more complex projects-that don't need the performance of C/C++-MicroPython is almost always vastly superior because it's generally much, much quicker and easier to create projects with MicroPython that with C/C++. Perhaps you would reply yet again, "Oh, but my viewers prefer C/C++!" If your viewers wanted you to teach them how to program 4 bit microcontrollers with Assembly would you teach them that? Are you trying to teach students about technologies that will serve them best, or are you merely pandering to viewers so that you can earn more money? You are an excellent teacher but you are misleading your viewers by having them waste their time with inferior technologies. ESP32s are cheap and powerful. Of course C/C++ applications will run on them. But for most projects most makers create, MicroPython on ESP32 is a better approach. It's not an accident in your real job that you work on ERP (which is not only an anachronistic technology but worse still, from the vantage point of ERP customers, has ** always ** been vastly inferior to using a "best of breed" approach). ERP is an anachronistic technology which many older engineers have spent decades learning and working with. I wonder if I need to find UKposts channel run by an engineer two or three decades younger than you who isn't stuck in the past, who actually embraces new and better technologies wholeheartedly. Older engineers who are looking forward to retirement, who half-heatedly espouse forward-thinking technologies, yet are unwilling to jettison years of obsolete learning, are extremely common. Most companies hire young engineers, in part, because young engineers are eager to learn and actually implement new technologies. Why not boldly take on a challenging real-world project so that you can teach your viewers how to efficiently and effectively solve small yet significant real world problems? Real engineering is often difficult. Making toy projects and playing around with gadgets you get in the mail from China is fun, easy, yet ultimately not worth very little unless that knowledge and those technologies are properly applied to solving real engineering problems. It's common knowledge that older ignorant engineers tend to indulge themselves by prattling on about technologies which they have spent decades learning. I'm neither pontificating nor am I haranguing you; I'm challenging you to "get out of your comfort zone" and become a great UKposts professor of engineering, instead merely being a retiree who devises clever methods for pulling balloons out of trees.

The 4809 chips were still available on Aliexpress and JLCPCB for assembly (3000pcs)

@@AndreasSpiess AliExprress is charging 3 to 4 times the normal prices, shortage will indeed drive up the price. But for a prototype design buying 2 or 3 at that price will be accessible. THanks for pointing out the JLCPCB stock, that my go-to- factory for prototyping. 73 to you and yours, and stay safe. Lex PH2LB

I do not know this line. Do they have a good Arduino IDE and library support?

@@AndreasSpiess I don't know much about Xmegas Arduino compatibility, because I have not used them with arduino. I know they have been ported to arduino though.

@@peerappel2012 atXmega family ? I have few atXmega128AU at here. Realy powerful avr 8bit mcu. Btw i need modify usbAsp to burn firmware via isp

​@@nguyenthinh6188 yeah, they use the PDI-interface for programming and debugging. I have also used a usbASP for programming them.

@@peerappel2012 btw it not popular at here. Few units i have come from "taken from industrial machine"

Thank you for the additional info!

For deep sleep ist is always better to use a bare chip, I think.

Hope you enjoyed the video

It is the tool's section of the Arduino IDE

The 4808 chips are hard to get, but the Chinese manufacturers seem to have enough for their boards (or the boards are already produced). The 4809 is available at LCSC

Gern geschehen!

Maybe. I like to have several possibilities...

I do not know this family:-( My first question always is: How about the Arduino IDE and library support? And my second: Do I get boards on Aliexpress?

@@AndreasSpiess Absolutely agree with this The AVR-Dx parts are better in every respect. There is a very good Arduino core (DxCore) on Github and there are Microchip and 3rd party boards available. UPDI programming can be achieved with a common USB/serial adapter and a single resistor. All my current 8-bit projects use this chip. The AVR128DA28 costs $2 and has 16K SRAM, 128KB flash and runs at 24MHz without a crystal from 1.8 - 5V. The -DB family has MVIO - you can run the chip at 5V and some of the pins at 3.3V, so you don't need an external voltage level shifter, And the most important thing ... they are actually in stock to buy now.

@@AndreasSpiess SpenceKonde/DxCore is github repository, haven't seen t boards yet

Good decision, I think. Do you have open-sourced your PCBs?

@@AndreasSpiess Oh no, I can't even use GIT, But if you want i can send you some pcb's

@@andreasnocker9877 I have a bunch of 4809s on order and would like to get such a PCB. Maybe you contact me on Twitter or Facebook messenger for my address?

Thank you for the info. FastLED is no surprise for me. NRF24 is surprizing because I do not see where it uses special things.

@@AndreasSpiess Well, it's Radiohead's NRF24 library that doesn't compile for me. I will check TMRh20's RF24 library. I think this may work. Gotta do more testing.

But I am already a subscriber and I’ve watched your videos for 2 weeks now, so it’s suggesting similar interets

Very good that Google shows you my videos :-)

See last entries in my link collection in the video description

AFAIK the Arduino IDE does not support this chip yet (see other comment).

Glad you think so!

Strange. Do you use an ad-blocker?

@@AndreasSpiess I use Pi-hole. When turning it of It works. 😬 😬 😬

they have one..... Atmega2560 (used on arduino mega boards) has 256kb program memory, 8Kb ram, 4Kb EEPROM then there is also the Atmega128-16AI... in TQFP64 form...4Kb ram, 128Kb program memory, 4Kb EEPROM then theres the Atmega640 with 64Kb... sounds like someone hasnt done ANY research....

@@WacKEDmaN funnily enough that's the ones I was using. So maybe I want even mooooore ram and program memory, and probably a rewrite. I just couldn't remember what the number was. For context sometimes it's difficult or even impossible to avoid strings and lots of libraries, a combination of both use a lot of storage and ram causing problems. Its easy to say don't use strings but the end result needed a lot of info to be sent as one long string to be used in its destination correctly.

@@dennis8196 bloated libs by the sounds of it...i use Atmega32A on a z80-mbc2, if i use wrong libs (eg bloated) it wont fit into program memory...but after hunting for some lightweight libs i ended up getting my additions in, with room to spare (think LCD/TFT libs!...some a bloatware, some are lean and mean!)... i also found compiling with the switch for "Compiler LTO" (available from the menu with Mightycore) decreased the size of the sketch by a good 20Kb, allowing me to squeeze even more in...

For larger projects I tend to use the ESP32. These 8-bitters are good for the small stuff, I think.

@@AndreasSpiess when I started the project way back the ESP series wasn't even on my radar, possibly not even available. I probably will use them when I recreate it. I can now make better cases with PLA, write better code and understand libraries better, so overall the V2 will be much much better.

You are welcome!

Coming of age? No, its really more like over the hill when many other options exist.

@@boots7859 True, but then again, so am I. And like many 'old' people, we like to hold on to the past, although I must admit that I'm very fond of ESP's too... ;-)

If the Arduino is over the hill, where am I with my 65 years ;-)

@@AndreasSpiess Many men like us will mental stay in their mid 20-ties. Forever young I guess. But indeed, the bodywork is getting older and we can't ignore some defects...

The CCL is a very specific functionality and hard to use. Here you find an example: ukposts.info/have/v-deo/aZVjgYx-eIyTu4E.html

I do not know this family :-(

for UPDI you do not need a bootloader - that's most probably why you need to choose "no bootloader". Also using direct port access in the "old" ATmegas is not cheating, it's the native way to do things. The new IO-blocks of the ATmega4808 have additional hardware registers for individual bit access which are wrapped into the new Arduino _fast_-functions.

You are right. UPDI programming and "bootloader" programming are different ways. For UPDI, you have to select another function in the Arduino IDE (upload with programmer or so). I did not know that the new nanos come with this feature. Mine are quite old...

Interesting project, a comination of an Atmel and a Z80 :-)

And the 4809 (3000pcs) is available at JLCPCB for assembly...

I agree!

We find the 555 timer still in use. And the 741 op amp, and the 7400 quad NAND gate chip. All 3 chips more than 50 years old.Even the 6502 and Z80 are still in production.The 80286 is still in use in Avionics.

A lot of people still use the Atmel chips. But the Pico is a good choice, too. Not too much appreciated by the Maker community if I look at the published projects

@@AndreasSpiess but that's because the chips in the Atmega 328 family were popular through most of the last 2 decades and have a lot of ready to use shield. For a new project, is there any real advantage to picking the ATmega4808 other than power efficiency? The Pico is cheaper, faster, has more expansion, USB, AND is easier to buy. If the 4808 was available for 2$ as a DIP chip that would be completely different!

You are right, the original has such a bridge. And both have the 256B EEPROM

@@AndreasSpiess more importantly, the 328p has 1024B of EEPROM, so the 4808/9 have 1/4 the EEPROM space... if that's relevant to your design it's an important consideration. I guess it's easier to add an external EEPROM than to add SRAM.

Unfortunately, I do not do the decision for the libraries and have to stick with what is available. So far, the Pico did not catch fire in the Maker community which would be needed to get more support. Maybe it will change over time.

I see these also as advantages.

:-)

The Arduino Mega has a lot of pins. And often, people use port extenders for such projects.

@@AndreasSpiess Thanks! Yes you're right, I suppose it just feels a step backwards. Adafruit's SAMD51-based Grand Central is nice too but pricey

@@jamesdoubt6660 Indeed. So far I only saw SAMD21s on AliExpress.

The question is: What software is available?

Thank you for your information!

Where did you hear about the CLC? Is that a configurable logic cell i.e. a small fpga?

@@cannaroe1213 i had to google the chip to figure out whether it has USB, was looking on the official page. And then i stumbled upon the CLC. It appears to be configurable logic cells. Expecting the power of an FPGA out of it would be insanely silly, but given GAL are dead, there are actually some uses i could think of where it would come to good use even if it's insanely simple, because i have been tempted to use GAL in conjunction with a microcontroller before. I don't know CLC's exact scope of capabilities yet. Like i really don't need more than a couple cells to implement an i2s interface on top of an existing SPI interface.

@@cannaroe1213 it is indeed. It has only very few cells but can be enough and indeed be very handy to implement certain interfaces that would otherwise eat up a lot of cpu time.

I had a short look at the CLC. It seems to be quite limited as @Peer writes.

It should be easy. Just the minimum configuration on a PCB. You even could have the board assembled by JLCPCB. They still have 3078 of ATmega4809 chips ready for assembly ;-)

Thanks for the info about the ADC

Try to get a Raspberry now. I saw ridiculous prices (100$+), too

Looking for this too, can you provide a link? Thank you

I added a link to the description (no links allowed here)

I do not know how good the library support of the Pico is now. I do not see a lot of projects using it :-(

These days most people use ESP32s if they need WiFi and lots of space. But the 1284 was also a good choice (it works in my LoRa mailbox sensor)

Level shifters are used to connect 5 volt and 3.3 volt logic level chips.

@@AndreasSpiess Well, they can connect 1.8v to 5v as well, or whatever, but you said you dont like to use them and I am asking why.

@@alexandrsoldiernetizen162 Because they need wiring and add complexity...

@@AndreasSpiess Fair enough, but its the only way you are going to get your RPi and Odroids and Beaglebones to talk to your TTL off the 40 pin headers, the only way to use the PWM and 1.8v analog in from the header, and it acts as an isolator to keep the demons of magic smoke from your delicate expensive linux SBC.

Welcome in the new world! I got a few 4809s on Aliexpress and LSCS has them in stock, too.

Well possible. But I do not know since when it is supported by the Arduino IDE.

You are right. I thought the clone has a bootloader. But it has such a chip, too (see pinned comment)

The Arduinos also have PWM pins. Maybe this is a good way to create fast changing signals, too.

@@AndreasSpiess Oh I'm aware there's a few PWM pins, just, how many is the issue. What I mean by that is, if all of the digital I/O can reach update rates in the multiple MHz, there's no need for dedicated pins, and every output pin could just be treated as an analog stream. For the (musical) synth folks, that would mean multitimbral voices only limited by pincount. Something like the mintysynth, but instead of 4-voice, it's 21 voice. I understand that the Uno's speed limitations would make it unfeasible to actually do it, as there would simply not be enough cputime to update all of the pins in time. Now that I think of it, it's probably better to modularise, and keep 1 mcu per voice, and make an overarching control scheme. Maybe it's better for this kind of idea to be implemented in FPGA form..

If it is not supported by the Arduino IDE it does not exist for this channel :-( This is a decision I made a few years ago.

@@AndreasSpiess hopefully they'll get popular enough for arduino support! thanks for your attention

The compilation time seems to be faster, yes. Unfortunately, everything from China became more expensive. I fear we must get accustomed to it :-(

I agree, prices went up a lot lately, also for simple boards. As I said: I would not compare them with an ESP32. EOL of the 328 will only be in a few years, I think. Earlier we will no longer find a lot of good 5-volt sensors, I think.

@@AndreasSpiess It's stunning how inexpensive the expensive boards have gotten, and how expensive the inexpensive boards have gotten. I'm overwhelmed with fast new boards. I wrote Teensy off years ago as too expensive. But a superscalar 600 MHz Teensy 4.0 with predictive branching and double-precision hardware floating point for $20?? And I thought the ESP32 was a steal! :o

@@d.jensen5153 It's much likely the mass production / success of some chips. Especially in special times like the last 1-2 years where the production is limited and the demand is high "old hobbyist" chips get more expensive while mass produced ESPs, that are in a lot of IOT devices, stay stable or get even cheaper.

Good idea. Maybe you are right.

Another possibility to consider is a liquid flow sensor, allowing you to track the quantity dispensed. Google "liquid flow sensor" and "water flow sensor" for examples from places like Seed Studio, Mouser and DigiKey.

@@BusyElectrons I have considered this but do not know the exact capacity of my tank, also its run by a 12v pump to supply all the faucets, I have a feeling this may also make it hard to calculate the flow rate with the pump force?

@@montaguemonro565 I've studied various approaches to the "liquid level in a tank" problem but haven't implemented a system myself, so my comment may have limited value. Perhaps someone more knowledgeable will chime in.

I made a video about pressure sensors. And read also the comments.

What about using an ultrasound sensor? Or a flow sensor like used in gas pumps at gas stations ? The ultrasound sensor can measure the height of the water level. You can find waterproof ultrasound sensor with electronics on Aliexpress.They look like the reverse sensor used in cars. The flow sensors have an input and an output and will give pulses for each liter of water passing through it.

You are right, they are not new. New are that those boards appeared on Aliexpress (at least for me)

@@AndreasSpiess i agree, recently board nano every 4808 more easy to buy , i got 3 of them from Shopee platform ( seller come from AliEx and re-up to Shopee) . btw i waiting for Atmega4809 Dip-40 - last model have DIP instead qfn,tqfp,...

You are welcome!

Why do you ask? This board costs 550$ excluding VAT.

@@AndreasSpiess Because it is a good board and has built in IEEE754 standard math and it is extremely fast and can take machine code like... fldt %0 fldt %1 fmulp %%st,%%st(1) fstpt %2 ret

Thanks for sharing. This is an old library, and I had known it for a long time... And I only use Google for my searches.

@@AndreasSpiess thanks alot for your continuous caring and replies

The further you go away from the Atmel architecture the more differences you have to cover. But for sure, STM chips are a good alternative.

I do not know. But Arduinos had no big issues in this domain. So I assume this did not change.

If you do not change the resistor the chip runs on 5 volts. If you change the resistor to 3.3 volts, it runs on 3.3 volts and officially is not 5 volts tolerant.

These 8 bit chips will no more get a lot of new functions, I fear.

As a Maker with time constraints, I depend a lot on libraries and ready-made projects. Therefore, I love the Arduino ecosystem. The TI chips for sure are good, but never adopted by the Maker community

The RP2040 is an ok alternative if you get the library support you need. It is cheap, but often shipping is expensive...

The ATTiny85 is a cool chip and I like it. However probably a different class because of the number of pins...

If you run it at 5 Volt it is no problem. At 3.3 Volt the datasheet does not allow 5V at the data pins.

I only know of the ESP8266 being 5v tolerant (confirmed by the CEO). I never heard the same for the ESP32. And reading the datasheets you hardly find more than VDD+0.5 volts. So it is up to you to try it. Please not with the Raspberry. There I read that it is killed nearly immediately;-)

some of new models have multi voltage io with builtin shifter..

google says: The AVR® DB Family of microcontrollers is equipped with a configurable integrated level shifter. and i say: in europe these are +50 to +100% more expensive compared to last year and harder to get with new delivery times from 3 to 6+ months for devices out of stock..

Just check the datasheets. I do not know MCU specs by heart :-(

Me too

Thank you for the info!

:-)

No