#345

[@hygri]

The guy with the Swiss Accent - Smashing the Arduino learning curve into a pancake since Video #1.

[@AndreasSpiess]

Thank you!

[@Bravo_L]

The guy with the Swiss accent knows alot of cool things for sure 👍

[@iforce2d]

Depending on what you're making, the larger memory of the ESP32 can be a HUUUGE win, probably should have been given a mention in your summary

[@AndreasSpiess]

Thanks for the addition. Coming from the ESPs I did not think too much about memory. Maybe I will miss it when I do more with STM32... BTW: Did not see a Video since a Long time on your channel. Always love them!

[@Stopinvadingmyhardware]

@@AndreasSpiessstop the pill shit. These people don’t even care what they did to our lives

[@bananaman2495]

@@Stopinvadingmyhardware what?

[@Stopinvadingmyhardware]

@@bananaman2495 Nobody asked you a damn thing

[@mattmurphy7030]

@@Stopinvadingmyhardwaresomeone needs their pills…

[@anvz6]

Atvantages of stm32: it can act as USB keyboard, serial, even as USB storage... All at the same time if needed.

[@AndreasSpiess]

True. I did not mention this fact explicitly. I only used this feature for upload.

[@ami6packs]

@@cambouiscom it supports hid.

[@ami6packs]

And DMA too. It makes coding a lot easier in case of data sampling e.g. ADC Samp.

[@arduinoguru7233]

@@cambouiscom HID works on it .

[@crosswick]

Also, the F105 and F107 have USB-OTG functionality (as do some more expensive ones)

[@RTmadnesstoo]

I always wait a while to watch your videos so the comment section can fill up. Sometimes the comments are almost as good as the video. Almost. Thanks for your efforts.

[@AndreasSpiess]

You are right. I am proud of my commenters. They know much more than me alone.

[@RTmadnesstoo]

@@AndreasSpiess Well, nobody has taught me more than you. Thanks, again.

[@beauslim]

You always seem to know exactly what I'm wondering about. Thanks so much for the comprehensive comparison.

[@AndreasSpiess]

You are welcome!

[@mxmxjrjr]

The most kind heart to make this video

[@AndreasSpiess]

Unfortunately I do not understand :-(

[@mxmxjrjr]

@@AndreasSpiess someone like you who have resources showing knowledge like this on internet makes a lot of different for people who want to learn and only have youtube. If some day i want to build something and need to compare what you did, i do not need to try and error by buying each of those. Now i know what to choose for my project all thanks to your video. Great job you have done.

[@drbra1n]

STM32F4xx has FPU, USB OTG working in both, device and host mode (some MCUs have 2 ports), support for external FLASH/SRAM/LCD screen, internal RTC clock, support for SD cards. The debugging capabilities are also awesome - breakpoints, single stepping, memory & register view, SWO tracing. AFAIK, ESP32 can be debugged too :)

[@AndreasSpiess]

You are right. I made a video about debugging the ESP32. And I should get some F4 boards...

[@TimSavage-drummer]

The one big advantage I found for the STM32 is the ease at which I can set up a hardware debugger with the STM32Cube IDE. The STM32 Discovery boards are great for prototyping and cheap, I only use ESP boards now for wifi connectivity. Have a black pill driving my DIY modular synth as a MIDI to CV converter, the hardware debugger came in really handy for developing that.

[@AndreasSpiess]

You are right: A debugger is a good thing. I probably will try to use it, but with platformIO.

[@EdFrench_uk]

Most of the "Blue Pills" have an incorrect resistor, which means the USB interface wont be recognised on a lot of machines (I think it depends on your PC's USB driver chip). I think there is also some software problem as I haven't been able to get it to work consistently even when I fix the bad resistor.

[@giorgioboiero]

The problem with the USB is sometime related to the use of clones of the STM32 chip , not only the wrong USB resistor www.cnx-software.com/2020/03/22/how-to-detect-stm32-fakes/ List of STM32 compatible chips www.richis-lab.de/STM32.htm A good work around is to upload the firmware using the ST-LINK and then upload an USB HID bootloader github.com/Serasidis/STM32_HID_Bootloader

[@AndreasSpiess]

Thank you for the hint. I saw a remark about that resistor, but have no blue pill.

[@cbm80amiga]

@@AndreasSpiess In most cases "wrong" resistor doesn't cause any issues. At least I tested it on 9 computers I have at home - USB works as expected.

[@marcovalenti2621]

@@giorgioboiero where may i find a "healthy" Blue Pill ( For Healthy i mean that it doesn't have problem with HID)? (sorry for my bad english)

[@TomaszStachewicz]

@@marcovalenti2621 most new sold blue pills now have corrected usb pullup resistor. check out the photo of the boards underside, it's resistor r10. it should read 152 (1.5k ohm) and definitely not 103 (10k ohm)

[@jessiegashler427]

A genuinely clear and concise comparison of the two. I'll be subscribing to your channel based solely on this video. Fantastic work.

[@AndreasSpiess]

Welcome aboard the channel!

[@derecwilsom4546]

that little hand makes me so happy, i giggle every time I see it!

[@jankomuzykant1844]

Deadpool hand ;o)

[@derecwilsom4546]

@@jankomuzykant1844 lol now i like it even more!

[@rcfreakamit]

Great video! For me though, the main motivation for going with stm32 over arduino or esp32 is the much more capable (and more difficult to learn) STM CubeMX config suite with the STM32 eclipse IDE, with St-link debugger, rather than the difference in sheer hardware capabilities.

[@AndreasSpiess]

Good point!

[@evabaroni6693]

System workbench for STM32 (SW4STM32) by AC6 tools with cubeMX is my go to for these CPUs. Sorry but can't call Arduino an IDE after using SW4STM32.

[@RustedCroaker]

@@evabaroni6693 Did you tried Keil by any chance?

[@NotMarkKnopfler]

Great video. What I would really like to see is an STM32 video showing how the low power modes work. Particularly wake-on-interrupt. I would really like to see that. Thanks again, Andreas.

[@AndreasSpiess]

Power consuption is stuff for a whole video...

[@ch94086]

ST has some nice dev boards with the STM32L low power series. These dev boards (discovery) have a separate processor to measure chip power down to nanoamps, and there are tutorials demonstrating all the power modes. After wake, it can read the sleep power and show on the epaper display.

[@RRits57]

Would love to see this comparison as well

[@TheAoab50]

Many thanks again for the great efforts to give us comparison results ready and free.

[@AndreasSpiess]

My pleasure!

[@victorlacerda9659]

The blackpill stm32f411 or stm32f410 both was floating point hardware and a faster clock speed than the bluepill. This make thinking if stm32f4 could be a better choice for floating point calculation.

[@AndreasSpiess]

True! The Blackpills are in the mail...

[@m0rph171]

@@AndreasSpiess Would be really interesting to see the calculation result for the f4 blackpill!

[@Brandon-rc9vp]

Thank you for freely sharing such great content. It is intellectually interesting, quirkily entertaining, and best of all technically informative for us trying to get back to our roots in electronics and learn how to operate todays newfangled gadgets :) If I had to guess I would say you are one of those rare individuals that know what an exciter is and at the same time can hold your own at any maker fair today. Good on you sir!

[@AndreasSpiess]

Thank you for your kind words! And enjoy your hobby (again). Quite a few of my viewers report the same. We live in a beautiful (electronics) time.

[@crckdns]

I personally am using the blackpill for smaller projects. Great video as always! Please more STM32 content 😻👍 (we use them also in our flight controllers ^^)

[@AndreasSpiess]

I think I will have a look at the interest and decide about the future plans.

[@giorgioboiero]

Some information about the Black Pill STM32F4x1 from the chinese designer github.com/WeActTC/MiniF4-STM32F4x1 It's now supported by STM32Duino but it's not yet integrated the USB Bootloader of WeAct

[@happysingh-gk2dj]

Hiii brother can u send your email.i want to learn black pill

[@alfredopreciadomolina1576]

wow, just what I was looking for, you can't ask for a better explanation, as always, master.

[@AndreasSpiess]

Glad you liked it!

[@EdFrench_uk]

I like both, I haven't looked much at power consumption on the stm32- that might be something where it wins a bit? I don't think anyone has done a video on stm32 sleep modes and power consumption with Arduino?

[@AndreasSpiess]

Power consumption is also on my list...

[@edwitte4752]

I believe Stm32 supports DMA for peripherals (ADC/ I2C etc). This can free up the processor for other tasks... Maybe add this one to the 'to do' list?

[@damny0utoobe]

@@AndreasSpiess STM32 also has the L0 lineup which is the ultra low power line. This one can run on a small battery for years. It's much more energy efficient than ESP32

[@lohikarhu734]

I missed a comparison of power consumption when running benchmarks... Also, just a note that the differences in non-floating-point are quite a bit smaller than the clock speed difference. Thanks very much for this work, i especially like the walk-through on software setup. Alles gute, MfG'n

[@AndreasSpiess]

I was also astonished about the small difference... This was an introduction and, depending on the response, I plan to do something with power consumption in the future.

[@lohikarhu734]

@@AndreasSpiess very good comparison, and i know that you are guided by comments, so it's clearly a fine response to those... as you probably note, i'm a bit of a 'picky' one on some things ;-) i kind of wonder at these microsecond(s) interrupt times, it would, perhaps, be interesting to see what code the compiler generates for IRQ handling, how much is stacked on entry. With 80 MHz clock rates, a fast IRQ should be sub-microsecond.... maybe a bit too deep for the average user?

[@AndreasSpiess]

I posted the measurements done for digitalwrite in another comment. It takes nearly half of the time...

[@RickB3n]

I have a suggestion: Try also the ST Nucleo boards, i think it's a good alternative to "blue pill" or other.

[@AndreasSpiess]

I thought they were bigger and more expensive?

[@RickB3n]

@@AndreasSpiess I understand, but an original Arduino UNO is more expensive. The ST Nucleo costs between 10 and 40$ For a hobbist it's possible. ST if you read this give me more boards 😂

[@anvz6]

@@RickB3n You can buy an UNO or a mini for 3€

[@RickB3n]

@@anvz6 It's true, but a chinese copy. They often also use a low quality clone for the atmega 328p.

[@SamupamIn]

@@AndreasSpiess you can buy stmf407vgt etc boards with more I/0 then mega or due at 10 USD from AliExpress.

[@shabbarvejlani]

Thank you Sir for your analysis ! Appreciate!

[@AndreasSpiess]

My pleasure!

[@curlybrace6694]

bluepill has software floating point implementation. esp32 has hardware. stm32f4 also has hardware floating point. xtensa is a very slow core, compared to cortex. even having much faster clock, it wins only a little bit in speed.

[@AndreasSpiess]

You are right with the speed difference: It was very small for port I/O and integer. Maybe I will do some tests with the F4 when I get it.

[@thegittubaba]

@@AndreasSpiess can you run ESP32 at slower clock? It'd be interesting to see the comparison when both are running at same clock frequency.

[@ragesmirk]

@@AndreasSpiess Use these boards: www.aliexpress.com/item/4000103610226.html I have them they are very high quality

[@Cracked1ce]

@@AndreasSpiess The F4 black pill is a beast. i am doing floating point calculations for engine management and the speed difference is astronomical. it takes nearly 700 clock cycles for the F1 for a floating point multiply or divide whereas it is instantaneous on the F4.

[@happysingh-gk2dj]

@@Cracked1ce hii brother can you send your contact or email I facing problem in blue pills ..thankyou

[@santorcuato]

Thanks Andreas. I do mainly IoT so WiFi is a must, even bluetooth to read some sensors, so... The ESP32 is not perfect but as a maker I focused on it and it works for me. Nevertheless it's always interesting to know some other alternatives to right choose in the future. Good job!

[@AndreasSpiess]

That was the purpose of the video. To know the choices.

[@AttilaAsztalos]

If one needs WiFi there's simply no alternative to the ESP32 series. On the other hand, not a single project I did ever needed WiFi and at that point that RTOS and WiFi stack preempting everything you do is just a liability.

[@moudi0082]

stm32 f4 and f7 series have built in FPU for floating point operations

[@AndreasSpiess]

You are right!

[@breedj1]

When using the esp32 be sure to use float and not double when optimizing for speed. Using floats is about 10 times faster. The floating point unit is not used for doubles.

[@AndreasSpiess]

Thanks for the info!

[@wingedrhinotv]

This is the first thing I'm seeing after waking up late on a Sunday, having spent the whole night dreaming about pitch detection algorithms. Wish I was a little more normal 😂

[@AndreasSpiess]

Nice you remember what you dreamed of. I never remember :-(

[@MiniLuv-1984]

I think the correct word is fretting rather than dreaming.

[@hamjudo]

An FFT is a common way to get a list of approximate frequencies out of a microphone or other noisy analog source. I've never needed very precise frequencies, so I haven't any experience with those algorithms.

[@stephenborntrager6542]

FFT is probably better, but one simple method that I know if is to set a window of a several thousand samples (maybe 4x the max frequency you care about), measure the time between peaks, and then average the periods. 1 / period (seconds) = frequency (Hz). From there, tables can be used to lookup "notes" ie A4 = 440Hz. I don't know how well it works, since it was a very crude method and I never actually used it. Probably won't work with lots of harmonic content. Might need to weigh the sample periods by the amplitude or something... or add some sort of hysteresis to keep the output stable... Great. Now I'M stuck thinking about them!

[@williamdunn5081]

Normal is totally overrated.

[@Promilus1984]

Comparison of ESP32 with really old Cortex-M3 based STM32F1 proved bluepill is pretty decent hw. Blackpill is even faster. Usually there's nearly 50% performance gain just by using higher clock rate and STM32F4 does have integrated FPU as well so doesn't suffer such penalty as STM32F1. Both flash and ram are significantly bigger as well than old F1 and architecture is based on Cortex-M4 so with additional dsp instructions. That makes it pretty big improvement. I hope you will be so kind to repeat tests once you get hold on STM32F411 based black pill :)

[@AndreasSpiess]

You are right. But I think, speed and flash size are not real limitations for most makers. This is why I did not focus on those features. The FPU is a game changer if you need it. This is why I mentioned it. I have no plans for the moment, but this easily can change ;-)

[@mr.meticulous1241]

Exactly the video I was waiting for! Thanks Andreas :)

[@AndreasSpiess]

Glad you enjoyed it!

[@yunshi7786]

Thank you very much for such a detailed and clear comparison. Since they are all pretty cheap, I’ll buy all of them to have a try and compare the outputs in my projects.

[@AndreasSpiess]

You are welcome!

[@unclejoe8310]

Where the hell do you get STM32 chips right now 🥴

[@sharana.p5921]

My favourite is STM32. Please make video to program esp8266 using embedded c or bare metal programming. Thank you.

[@AndreasSpiess]

I will stick to the Arduino IDE :-( But I did a video about assembler programming of the ESP32

[@sharana.p5921]

@@AndreasSpiess Oh ok thank you Mr. Andreas and another one is there, what about making a RF circuit like 435 MHz 4 channel or 8 channel circuit from scratch? Would you make it si, please.

[@muflah]

It was hard for me to convince my co-workers to look at esp32. Earlier they were using stm32 with esp8266 in master/slave configuration. Now the go-to choice is esp32 for most projects.

[@AndreasSpiess]

If you need connectivity, the ESP32 is for sure the better choice.

[@WacKEDmaN]

apples vs oranges... ESP32 has wifi and bluetooth... STM32 does not...it all depends on the use and features needed..

[@AndreasSpiess]

I thought I covered these things in the video...

[@WacKEDmaN]

@@AndreasSpiess sorry mate..i deleted that bit after i seen you covered it! :P

[@zoli11]

Not quite. I have been doing stuff with ESP32, but this comparison showed me that even if I don't need wifi, in most cases I don't miss out if I just keep using those, and save myself the trouble of getting familiar with a different setup.

[@newburypi]

Yet again, both useful and interesting. Thank you.

[@AndreasSpiess]

My pleasure!

[@cwbh10]

Lol I just replaced my "Blue Pill" with an ESP32 on a project I'm working on, since the community support for the ESP32 is just better

[@AndreasSpiess]

I think you are right with the community.

[@cwbh10]

@@AndreasSpiess In my specific case I was trying to use the NRF24 modules, and it worked flawlessly with the RF24 library on the ESP32 and not the STM32. I figured I could get it working, but for the project the time is important and if it just works, I'm going to go with that device (mostly)

[@danielegger6460]

Outside of Arduino the support and community for Cortex-M MCUs is way beyond the support for ESP32 and AVR MCUs combined. I'm actually slightly disappointed that Andreas Spiess fell back to using the lame Arduino instead of going for platformIO which would have allowed for a much better comparison.

[@Vicolaships]

Give libopencm3 a chance, it's a great hardware library with a nice community and documentation (libopencm3.org/docs/latest/stm32f1/html/modules.html ). STM32 for Arduino is a little bit dead and the code quality is poor. libopencm3 for Blue-Pill examples here: (C or C++, project configured with CMake): gitlab.com/VictorLamoine/libopencm3_bluepill_examples. You can pick any IDE you like that supports CMake, I like KDevelop. "Beginning STM32: Developing with FreeRTOS, libopencm3 and GCC" (Warren Gay) book is a great way to get started with practical examples and explanations. If you want to do some real-time (detailed in Warren Gay book) check-out: gitlab.com/VictorLamoine/libopencm3_freertos_bluepill_examples Feel free to reach me for help!

[@AndreasSpiess]

@Daniel: Can you contact me to discuss the integration into platformIO?

[@a1nelson]

Thanks for all the good work you do channel. I’ve learned a lot from it and look forward to new videos. This one, unfortunately, was the rare exception when I cannot really agree with your conclusions. The main issue is that the STM32 model chosen, while being very cheap and popular, isn’t really in the same class as the ESP32. In STM32F4 or STM32L4 would have been more appropriate, since they have similar clock speeds and feature an FPU (among other things). The other thing is that, in the absence of at least two excellent voltage references, pretty much all ADCs need to be calibrated. Their output magnitude and slope are relative, not absolute - despite what the datasheets imply. As an aside, neither board has very much in the way of decoupling, so noise is going to be a significant factor too. STM recommends a ferrite bead or independent decoupling for the VDDA input, but the blue pill and other low-cost boards do not have those parts. Based on the form factor, I doubt the ESP32 boards have them either. If the data points for the comparison were not collected under the same conditions (at about the same time), that adds a lot of uncertainty. Just things to consider. Thanks again for all your hard work.

[@AndreasSpiess]

You are right with the FPU. I will look at it in a future video. And about noise reduction on boards: The ADC of the Maple Mini was better than the ESP32 in the configuration bought by my viewers. And this is what counts on this channel. I am sure all boards could be improved if buyers would see the differences pay a little more. But platforms like AliExpress support a race to the bottom price. So, if you want a decent board, you have to make your own. Which is also not too complicated anymore.

[@a1nelson]

Andreas Spiess Thanks for your quick and thoughtful reply. What you said makes very good sense. It caused me to check my assumptions. The first is that, as one moves beyond just flashing an LED, the cost of the MCU board becomes a smaller and smaller part of the total system cost. Using a board with better ADCs or more IO pins may be easily justified by eliminating the need for IO expanders, external ADCs, more complicated software, etc. But, importantly, not every project requires that. You mentioned checking battery voltage, which is a good example of a situation when high accuracy isn’t critical. My second assumption was related to your final comment. Although I have a handful of STM dev boards, Teensys, etc., for non-trivial projects, I often just roll a new board. And, although it’s pretty easy to do so, it’s definitely not for everyone. So, after a bit of reflection, I do appreciate your position much better. Thanks again. Be well.

[@Ottmar555]

@@a1nelson Do you have the reference about using ferrite in the VDDA input? I'm having a little more noise than I'd like for my application in my ADC, and a moving average is not a good option, since I need fast code. Do you have any suggestions?

[@mrrboo]

Thx for the interesting video. I think it's also a matter of "makers" VS "pro", in a pro embedded development environment STM32 is the king (with ST official boards, mbed dev environment for example more than Arduino) and ESP + Arduino rules the makers market. In my company we use a lot of STM32 dev boards, you can find official STM32 "Arduino nano format" boards with Cortex-M4F for 10€ like the NUCLEO-L432KC

[@AndreasSpiess]

You are right about the different environments. For professional usage, you usually go with the supplier tools. On this channel, most users use Arduino IDE because they do not use STM chips as a first choice.

[@sullivanzheng9586]

ESP32 actually has quite fast ADCs with at least 650Ksps speed if using DMA. The problem is lack of documentation to enable this feature. I spent a few weeks hacking and testing this feature. Now I am working on an ESP32 SDR, and I think it is the best MCU for hobbyist to build an SDR, because: 1) ADC with 650 ksps effective sample rate. Sufficient bandwidth to demodulate FM and LORA baseband. 2) dual core + very powerful FPU. No more fixed-point/integer DSP algorithm workarounds. 3) Lots of SRAM compared with similar priced development boards. 4) ESP32 DSP library, integrated into ESP32 Arduino Core v2.0+. Optimized at assembly level and can do FFT 2x faster than arduinoFFT. It has complex number support, IIR, FIR, Matrix manipulations etc. Really amazing. ESP32 really has lots of processing power, and probably the best processing power for the money.

[@AndreasSpiess]

Welcome to the club! We are already a few who try to use the ESP32 for SDR projects. Maybe you watch my video about a marvellous audio library. It can save a lot of time. NA5Y is one of team. Maybe you watch his channel, too. And I created a Discord channel (sdr-stuff) for us (invitation link: discord.gg/JfgDSa8 ). You have to add https to the address because KZbin does not like links.

[@bobblaine1437]

Thank you for the very useful video. I've been curious where the STM32 fit in the micro controller pecking order, and when to use it.

[@AndreasSpiess]

There are many more STM chips. I assume I will cover a few more to get an overview.

[@theboots39]

Thank you for this video. I was trying to answer this exact question for the last week. I've been using esp32, but I rarely have any need for internet connectivity. At the moment, I don't think it's worth changing over, but definitely a consideration for future projects. Perfect timing!

[@AndreasSpiess]

Without Wi-Fi the STM32 boards are a good selection, I think

[@tigercat3864]

I abandoned the Blue Pill because there's no reliable supply of legit or even consistent boards. Too many of them are fakes or bad clones that don't work reliably. It's ESP8266/ESP32 & Teensy FTW.

[@AndreasSpiess]

Thank you for sharing your experience!

[@leonardoh6140]

@ 7:14 a wise man said: When you "pluck" the usb "pluck"... Just kiddind, nice video as always!

[@AndreasSpiess]

:-)

[@MithatKonar]

A word of caution around "Black Pills": There are (at least) two different strains of products using the "Black Pill" moniker out there. Before the current crop of STM32F4-based Black Pills were a thing, RobotDyn started making several modules based on the STM32F1 Blue Pill and referred to them as Black Pills. These are very good STM32F1 modules -- in black rather than blue. They are not what the cool kids mean when they talk about Black Pills.

[@AndreasSpiess]

I odered boards with an F4 chip and hope I will get the right chips..

[@Aerrow62]

There are F versions of STM32 series using M4 cores that have hardware floating point support.

[@AndreasSpiess]

True. The blackpill in the Mail will be such a F4 version

[@Aerrow62]

@@AndreasSpiess I personally prefer the STM32F303 series. Have full float and are M4 cores. Really cheap. I love the IDE generating initialization code for me. Life is so much simpler with it and the HAL is pretty well written.

[@FilipLamparski]

Many STM32 MCUs support Arm's mbed environment which is somewhat similar to Arduino but can be used across many different Arm microcontrollers, and has a number of cross platform libraries that work across a wide range of boards. Heck, some of the newer Arm based arduinos are implemented on top of mbed. It's also very easy to use since you don't have to install anything if you don't want to - you can code in the browser, download a BIN file, and then drag it into a USB mass storage device presented by the debugger circuitry on your board. I think most "official" boards support this workflow, like the Nucleos.

[@AndreasSpiess]

Sounds simple. On this channel I will stick with the Arduino IDE because it is the "smallest common denominator"...

[@fullsolutionslab]

Dear Andreas. As you told us in another video from you, you are a true swiss biker :) and I dont mean a bicycle-biker but a motorcycle biker! because I'm a Swiss biker too, it would be cool if you can make a motorcycle project. For example to collect multiple data by riding like speed, real-time, position (GPS), temperature, humidity, pressure, angle of the motorcycle, acceleration, break way (how long it takes), distance from the wheels to the chassis (to record if the street is rough), power consumtion an so on. then collect all the data in an excel sheet and do some machine learning to evaluate your driving style and to see if your driving style is good or not. then of course with real time online update with a GSM module and connect all sensors to each other by wifi or something similar like BT. The whole system could be controlled via a voice regonition interface or a gesture sensor and all data could be displayed on a TFT display or maybe a Nextion. And to round up everything an ESP32-Cam could record everything on your way. What do you think? I'm creating something similar at the moment, but it would be realy cool to see how you would do a project like this ;) I hope you stay healthy and keep corona free :o) kind regards, delf from Bern

[@AndreasSpiess]

As you might know, I am an old man and therefore I own a Harley: So most of the things you want to measure are not of interest to me anymore ;-) The only thing I measure is fun per time... So you need a younger, more ambitious guy for such a project. BTW: I have a Hero on my bike to keep the impressions of our journeys.

[@iforce2d]

Many of those things could be recorded pretty well by just slapping an Ardupilot board on :)

[@fullsolutionslab]

​@@AndreasSpiess Come on Andreas, you are not an old man yet. Take a look on all miracles you are doing, inventing and sharing with us. I think because of your grey hears you look older than you are ;o) I'm just joking :) I can fully understand, that you arent interessted in a motorcycle data capture project. Thats ok. The reason, why I have proposed this project is, because I miss sometimes some realistic applications in your nearly perfect video's. Everytime you explain very complicated stuff so good, that even the biggest noob can understand what you are teaching. The part, that you are allready doing for long time has nothing on it that I could do critics on it. But unfortunely I often have not enough ideas how to use your content in real life. Maybe if you like you could make a project with a real life application/use. You have done a lot of LoRa instructions and presentations. Some of your LoRa instructions i have successfully achieved. Now I have a LoRa Gateway and some working LoRa modules. But what can I do now with them? For what should or could I use it? Very nice to have, but till now useless for me :) But I had a lot of fun to replicate your instructions.It was very cool ;) Yeah, maybe you have more ideas than me for the future. I hope you stay healthy and I wish you only the best :) Kind regards

[@AndreasSpiess]

I agree that I often leave the imagination to my viewers. But this is how I am built. My firm belief is, that the wish is the first thing in a project, especially in hobby. I have quite a few videos where I show how I use it (for example the hacked garage door opener below the saddle on my Harley). But often I only want to spark the imagination of my viewers. LoRaWAN is a special case because it is a technology with a lot of enthusiasm but not a lot of applications for the average Maker. I liked it because I am a HAM operator and love RF stuff. I also thought I can help a lot of people with my knowledge in these areas.

[@BluCasper]

Thank you for such an amazing content. It was really helpful. Stay safe and have a great day. Best wishes for you.

[@AndreasSpiess]

You are welcome! I am vaccinated twice already:-)

[@BluCasper]

@@AndreasSpiess that's great. waiting for your upcoming videos. if possible please make a video how a newbie can program esp with micropython and use AI somehow to make something intelligent.

[@AndreasSpiess]

This channel is more for the advanced (or at least ambitious) Maker. So you probably will not find stuff for beginners...

[@BluCasper]

​@@AndreasSpiess there are tons of channels for beginners. I like your contents sepcially the comparing. But i think you should make another video comparing different ESPs and different STM MCUs. How good are other ARM products from atmel, TI and other brands. It'd be really helpful. Thanks in advance

[@phymacillustrator]

Thank you so much, It helped me to understand options to program STM32. Thanks again.

[@AndreasSpiess]

You are welcome!

[@triggerthesound767]

You did one video on circuit python and yet you seem determined to stick with the Arduino IDE. why is that? It seems really slow and awkward and terrible. Is it just because it is by now so widely used? If so then why wouldn’t we keep using magnetic tape media, to use one example.

[@AndreasSpiess]

Which IDE should I use in the future according to your experience? And maybe you read the comments in the Micropython video if you want what would happen to this channel if I would switch to it :-(

[@triggerthesound767]

Andreas Spiess sure, will do. I would just like to see a video from you using micro python or circuit python, or Make:code, just to see what your opinion is of something other than Arduino.

[@asm_nop]

In my college courses, we used a board running an STM32F405. That board runs a Cortex-M4F at up to 168MHz with an integrated FPU. It's more expensive, but it was extremely capable, had multiple separate ADCs/DACs, etc.

[@AndreasSpiess]

As I mentioned, I should get some F4 blackpills.

[@georgegu3374]

availability of libraries, documentations, and example projects are crucial. price is probably the least of concern, unless you plan for mass production.

[@AndreasSpiess]

The Maker community is quite price sensitive, I think. Maybe because of the cheap Chinese prices in the past

[@johanmartijn]

The advantage of the STM32 is native USB support. I use them as a USB microphone with the ADC. But the programming is done in STCubeMX and not Arduino

[@AndreasSpiess]

I concentrate on the Arduino IDE on this channel because most of the viewers use it. This can be a disadvantage compared with the native IDEs. But it is well known and also work for other chips.

[@xConundrumx]

The main advantage imho to the STM32 boards is the STM32Cube software that allows you to configure the chips truly purpose driven ways and turning off anything you do not need. The memory depends on the type of STM32 you are using and the implementation. Some even exceed the ESP32 memory setups.

[@user-mr3mf8lo7y]

True.. but that targets less than 20% of general makers. The rest (including me) either does not have enough knowledge of what to set in that software or, simply do not care.

[@xConundrumx]

@@user-mr3mf8lo7y And so that is why there is now support in the Arduino IDE I guess. Even so, it is there if you want it and especially for people that are looking for low power (to name but one example) the STM32Cube route is a definite option. On top of that there is tons of information on what to set and when available. Plus a ton of YT videos on it. All I am saying is it is worth looking into.

[@treelibrarian7618]

a little bit more on the STM32 ADC's ... no experience with ESP32 so I cant say how this stacks up... There are 2 ADC's, both operating at 1us, and can be configured to sample alternately or simultaneously and scan automatically over all 10 inputs in any order and with differing sampling gate times (longer gate times allow for higher impedence sources and greater stability) and can link with DMA for hands-off cyclical filling of a block of memory with ADC values with interrupts at 1/2-buffer intervals for processing. The DMA can also be used to cyclically write hardware registers from a range in memory, triggered by hardware interrupt, for hands-free PWM dithering or block serial send/receive, or anything else you can imagine doing by copying memory to hardware registers on interrupts. Speaking of interrupts, it may be possible to get even much faster interrupt response from the STM32 if you code it yourself and set up the interrupt pin wisely with maximum interrupt priority and minimum disambiguation overhead. Also, using the library functions like digitalwrite will add an overhead from all layers of calculations and function calls required to drill down to the actual hardware write. Should be possible (IRQ to GPIO) in ~14 cpu cycles (0.2µs). Finally, I've only ever used maple-mini clones which all came with the maple bootloader pre-loaded so I've only ever needed a USB cable to program them their only disadvantage was that one of the 10 ADC lines doesn't make it to the edge of the board. I do remember the "Red-pill" boards that were around at the time that STM32 was first being integrated into arduino, I seem to remember them being hard to make work but cheaper (missing something?). Blue-pill/Red-pill were terms coined to distinguish the blue solder-mask ones that worked better from the red solder-mask ones that often didn't in forum threads discussing how to make them work, since there wasn't much else to distinguish them.

[@AndreasSpiess]

Thank you for the additional information!

[@stefkpl]

@15:04 floating point is better on ESP32 because STM32 tested was a cortex M3 mcu @72Mhz (ESP32 run @240Mhz). If you use a black pill, I think the result will be better. It's cortex M4 @ 100Mhz but the price is closer to the ESP32.

[@AndreasSpiess]

You are right. But as I said, I had none available. Maybe later...

[@rondlh20]

15:00 It would be worth mentioning here that the ESP32 has much more ram and flash than the STM32 Arduinos (Uno, Nano etc.), it's shown at 4:00, but should be part of the conclusions too

[@AndreasSpiess]

You are right.

[@KerbalLauncher]

I really never understood why people don't just buy nucelo boards off digikey. They come with an embedded st-link! The PSOC6 prototyping kits are a great alternative to the ESP32 as well, much lower power consumption. The H7 series are really powerful and under $30.

[@user-mr3mf8lo7y]

When I finalized a RFID project, storage/EEPROM was the main consideration. Having 4MB of storage, clearly, ESP8266 was the winner. Still is.

[@AndreasSpiess]

Indeed, most other MCU boards do not offer this amount of flash...

[@PhG1961]

Thnxs for this very well explained overview. A nice wrap up !

[@AndreasSpiess]

Glad you enjoyed it!

[@PhG1961]

@@AndreasSpiess I always do ;-)

[@nicolaw6829]

I am a bit confused about the code on @11:38, and I think that this might not actually be adequate as integer benchmark. On each iteration, you set a pin as output, then you toggle it, then you set it as input (I think without any PU/PD), and you read it 3 times. If it is high, then you perform a multiplication (single cycle in a CM3), otherwise a remainder operation (the division takes 2-12 cycles on CM3). This code has some issues in my opinion: 1) If the pin is left floating, then it might perform randomly divisions or multiplications, depending on external noise and board layout. 2) Instead, if you force externally a logic level using a pull-up/pull-down resistor, then you are not actually getting the integer performance, as, for instance, the multiplication (and probably the division too) is much faster than the "digitalRead/Write" and "pinMode", functions, as they have a lot of overhead. I think that in this case you are just measuring how optimized is the bsp for a particular board instead. This might explain why a Cortex M3 at 84 MHz (Arduino 2) is more than 2 times slower than a Cortex M3 at 72 MHz (Maple)... (different flash caches on the STM32 and ATSAM3X8E might impact on the speed, but I would not expect a factor 2).

[@AndreasSpiess]

You are right and I should have corrected this if statement. But I wanted to keep it the same as in the first video. Also because it was not very important for me. Next time I will try to use a better sketch like calculating primes or so.

[@riscy00]

Wondered why cubIDE and Mx is not covered

[@AndreasSpiess]

Because I do not use proprietary IDEs on this channel.

[@riscy00]

@@AndreasSpiess That fair, Visual Code?, I just set up ESP32-C3 on Visual Code. It supports both STM32 and ESP32.

[@riscy00]

@@AndreasSpiess Okay, Visual Code supports both ESP32 and STM32. I just installed an extension from ESP32, which looks like a very complete package. I just ran a few demos.

[@riscy00]

I found out it may work out better on Visual Studio for debugging, which is a major shift away from being eclipse-based CubeIDE/MX. At the moment, I am reading through the IoT part with ESP32-C3 and seeing how this worked out in Visual Code and maybe with Platform IO.

[@brycedavey1252]

This shows how good the esp32 is, given it also has WiFi and Bluetooth!! It also has a core just for the Rf

[@AndreasSpiess]

The ESP32 is also newer. But it is definitely a good choice for many applications.

[@brycedavey1252]

@@AndreasSpiess One thing I would point out is that the STM32 product line has some very nice development boards. Plus the programmable brushless motor controllers are fantastic for DIY projects :) I do normally recommend the esp32 for beginners though if I'm honest

[@user-qr4jf4tv2x]

The beachmark part is like watching linus if microprocessor don't exist yet

[@trevorvanbremen4718]

At around 10:30-11:00 you talk about the (comparatively) s-l-o-w interrupts on both STM32 and ESP32. However, your example code makes use of the digitalWrite() function with the ISR. My experimentation on the Arduino Due (which is admittedly neither STM32 nor ESP32 - It's an ARM based ATMEL/Micrchip) showed that the digitalWrite() function is disgustingly s-l-o-w. I am willing to bet that your 2.5uS to 3uS of interrupt latency would drop to nanosecond levels if you were to emply direct port writes instead.

[@AndreasSpiess]

You are right with the STM. About 50% of the time is used for the digitalwrite. I posted the measurements in another comment.

[@AirzonesBlasters]

Regarding the Blue Pill resistor, it really depends on the PC you connect it to. Some are tolerant and some are not. In the STM32F103 based board I put together, it of course uses the correct resistor. However I have since changed the board design over to the STM32F411. And that's such a nice chip.

[@AndreasSpiess]

Thank you for the info. I will look at it as soon as I get my bluepills...

[@noweare1]

There are higher performance boards that ST has written arduino cores for like the F4 and F7. It really comes down to if you need BT or Wifi then the choice is clear. One thing though, migrating from arduino to HAL (ST native API) is much easier than going from arduino to IDF (Espressif native API) which is just overwhelming. Hard to beat form factor and price of the esp32. There is one thing that is hard to quantify is the fun factor of programming an 8 bit processor in an arduino environment. Even experienced enginners have to admit that it doesn't get much "funner" than that.

[@AndreasSpiess]

I think I mentioned that you get also support for other families and I should get some F4 blackpills. A lot of the viewers on this channel are not software engineers and they love the Arduino IDE also because of the help of a large community. Already finding information for the STM32 was much harder...

[@silverjohnson3163]

wifi is important to my projects, it's one of the very cool things about the 8266 and esp32 boards. Thanks for the review

[@AndreasSpiess]

Same here...

[@adrock0801]

Your comparison applies only if you are using Arduino IDE. In any other case, both chips have not only different hardware, but also completely differenct approaches. On a STM32 you can program "bare metal" with having full control of the MCU. In this case you have a consistent behavior for any aspect of the STM32 MCU (interrupts, memory, speed etc.). On a ESPxx you will never have full control as it has to do housekeeping etc. for the wifi connection, so it behaves like a shared ressource. However, both MCUs have their specific use cases, so like you already stated, there is no "better" MCU.

[@AndreasSpiess]

You are right. But on this channel, we use the Arduino IDE. That is why I did it this way.

[@hebersolisbravo4502]

Excelente análisis, me ayudo mucho en la selección para el proyecto. Muy bueno

[@AndreasSpiess]

Glad it helped!

[@stewartrv]

I like the Bluepill and the newer Blackpill's even more, especially if you get one with the extra memory. For about $5 it's very fast and will also run MicroPython. It's a pity you didn't have the new Blackpill baords yet. I hope you'll do a quick update with them when you get your hands on them. Oh and don't forget to have some USB-C cables on hand the blackpills use that now instead. 73

[@AndreasSpiess]

I have more and more USB-C cables. That should not be teh limitting factor ;-)

[@stewartrv]

@@AndreasSpiess I have Android only and so didn't have any USB-C and forgot to order at the same time :) I have a few now though! Of course you can program without a USB-C anyway.

[@R3VISION3]

I personally had to install the USB bootloader using the ST-Link only since the FTDI boards I ordered are still in the mail. I was about to recommend the video guide made by Caleb Marting back in February until I noticed it in the description, since that's the one that helped me figure out the bootloader flashing without having to use FTDI boards like most other videos seem to show.

[@AndreasSpiess]

Calebs video is very good. I found quite a few references on how to use ST-Link to flash the bootloader. But only blogs, not videos.

[@electronic7979]

Very helpful video 👍

[@AndreasSpiess]

Glad you think so!

[@mjyai]

Bluepill is probably refer to movie "The Matrix". But I'm not sure because later an improved version used black pcb and call Blackpill instead of using red pcb.

[@AndreasSpiess]

Indeed, the newer one is called Blackpill. So it is probably the color...

[@andys4777]

Thanks for the great video, but I wouldn refer to STM32F1 as just STM32. STM32 is a huge family, like x64, there is F0 that is even slower and there is STM32H7 that can be clocked at speeds up to 480 MHz with a benchmark performance greater than 1,000 DMIPS, so stating in the table that STM32 is slower than ESP32 on floating point is straight away misleading.

[@AndreasSpiess]

You are right. But for a comparison I had to chose one of the many boards. I did another comparison video with more STM chips

[@deangreenhough3479]

Good work Andreas 😁🏴󠁧󠁢󠁥󠁮󠁧󠁿

[@AndreasSpiess]

Thank you!

[@lmamakos]

I believe the interrupt response time latency is actually better than it appears. I believe that the Arduino GPIO "pin" library functions are rather slow; look at the width of the pulse on the scope, almost a microsecond to toggle the pin on and off. The STM32 processors have this "bit banding" memory region which maps a memory reference to a piece of address space to an individual pin, so you don't need to do a read OR/AND and write cycle to twiddle an individual bit in a GPIO control register.

[@AndreasSpiess]

You are right. I got to the same results after a few viewers mentioned the fact.

[@villageidiot8718]

If physical space is not an issue, I prefer the ESP32 with the external ADC. Thanks for this video

[@AndreasSpiess]

Good concept!

[@ivolol]

It's great of you to mention the makers of the software/firmware/libraries that enable all the tinkering!

[@AndreasSpiess]

We all stand on their shoulders and we should know that!

[@phinok.m.628]

The ATmega328P also has an internal reference voltage, you just have to activate it. Also, there are many STM32s. The STM32s with the Cortex-M7 cores running at 400 MHz for example also have FPUs and they are most certainly faster than the ESP32.

[@AndreasSpiess]

Video#10 shows how to use this internal reference. And when the Blackpills arrive I will for sure check them out.

[@blekenbleu]

Thanks; looking forward to a similar comparison for Nordic dongles

[@AndreasSpiess]

This is definitively on my list!

[@methauchohnegaming9327]

Other pros for the stm32: -for thr prize of the esp32 you can get a stmf411 Board which is faster has more ram/flash and floating point unit - CubeIde which makes complex programs and features like dma easy to access/use

[@AndreasSpiess]

I should get some Blackpills with an F4 chip

[@TheRainHarvester]

There is an archive for the stm32/Roger Clark forums...

[@TheRainHarvester]

web.archive.org/web/20190316154334/www.stm32duino.com/viewforum.php?f=19

[@TheRainHarvester]

I posted the link. Can anyone see it, or is it removed (shadow banned) by KZbin?

[@etmoimeme]

@@TheRainHarvester Thanks, but why has it been deleted?

[@AndreasSpiess]

Thank you for the link. I assume the links I googlef were links to his blog, not to his forum.

[@TheRainHarvester]

@@etmoimeme I could never find why it was deleted. I read that he didn't want to get sued, but I'm not sure why stm, or anyone, would sue him. The forum was so great !

[@DanDrown]

Thank you for creating this nice tutorial on the STM32 boards For the ADC, the Vref channel is not used automatically. You can read from it using readVref on the ADC object, but it looks like the code is incomplete.

[@AndreasSpiess]

Thanks for the info!

[@jewe37]

there is also the itm interface for stms programmed via an st link for printing. these st link sticks dont have the right swd pin broken out, but you can solder a wire to it and it works. alternatively you can buy one of those bigger stlink devices with a full jtag port and there it is broken out. you can hook that up to the stm and then print from it. the inoffical stm libraries dont support it, but the logic is fairly self contained and you can just copy paste it from the official package. on linux i am reading out using a very simple openocd config(which also allows very handy gdb debugging!), i dont know how you d do it on windows. it works great if you dont have any spare serial lines or dont wanna break out those pins as well.

[@AndreasSpiess]

Thanks for teh information. I anyway try to use debugging in the future.

[@ManfredBrauchle]

how much time is wasted on interrupts because of the _digitalWrite_ function? I remember that it was not very efficient ...

[@AndreasSpiess]

I just checked it. It takes about 700ns on the STM32. On the ESP32 it is only 120ns.

[@ATS3788]

The Main Problem with the STM Blue Pill is that the compile Code is huge so I did not even get the Fast LED code in the flash

[@vvhat]

There's a Timer and a SPI version of WS2812 libraries, all DMA.

[@DavidCaplinGIS]

Is there a plethora of weird and wacky STM boards? Like a soil moisture probe that is also a LoRa node?

[@AndreasSpiess]

I think the STM32 is more used in the professional environment.

[@robsinHL]

ESP-NOW makes it a no brainer if connecting multiple devices. ESP32 is fast, cheap with a ton of RAM. I stick with Espressif boards available on Mouser for like $10. Can get ESP32-S2 for $8 which handles low power properly, minus a processing core though.

[@christianlennertz5780]

Like always great video. I also like the „Black Pill“. The Stm32F411 is very good in my opinion. What I really like of it, is the integrated USB ports.

[@AndreasSpiess]

As I said, they are in the mail and for sure I will play with them...

[@TheNamelessOne12357]

STM32F1 is a very old MCU series, but even so it performed very well. You should compare ESP32 with STM32F4. It has more or less same price, but outperforms ESP32 by factor of 6 in floating point operations, and the interrupts will be much faster too because of the much higher frequency compared to F1. And for the low power application there is L-series. They can change their freqency, have many sleep modes and turn on/off peripherials on the fly to acheive minimal power consumption over time. Much better and easier than ESP32's ULP.

[@AndreasSpiess]

As said, I have F4 Blackpills in the mail. And a few others (including L0) on order. So stay tuned...

[@TheNamelessOne12357]

@@AndreasSpiess You should also try WB series - they are like L4, but with WiFi and Bluetooth. Maybe they will eventually replace that ugly complicated ESP32. :)

[@hzrnbugsie]

The latest and greatest Arduino Portena uses STM32 now

[@thomasscheidegger2847]

Yes, its Portenta H7 (STM32H747)

[@AndreasSpiess]

This board is probably too specialized for this channel. I also see no use case :-(

[@jean-marclugrin1902]

Thanks. I think you missed an important point: The STM32 has many 5V tolerant pins. This may be useful when you interact with a mixed environment (or just as a protection in case of error). In principle you can use for example 5V RS485 interfaces with it. The ESP32 is very stricly 3.3V. I do not compare the STM32 with the ESP32, but with the standard Arduino. I use them in a project because I can use their hardware serial ports, which is more convenient that the Arduino Nano where you have to use softserial. An Esp32 interfaces between Bluetooth and a driver STM32 (via one serial port), which itself send commands to other STM32 or arduino via RS485.

[@AndreasSpiess]

I did not start this comparison ;-) As I said, viewers started to compare Bluepills with the ESP32 in my interrupt and ADC videos. That is why I thought it would be valuable to know the differences.

[@AureliusR]

They are completely different microcontrollers for completely different applications. One isn't "better" than the other. If you need integrated wifi and are looking for low-cost, you go with the ESP32. If you need ARM Cortex power, and traceability/supply chain, you go STM32. They aren't really the kind you could just swap out.

[@AndreasSpiess]

You are right. I meant "Better for a particular purpose"

[@namesurname5005]

Combining Visual Studio code with Platform IO and STM32 works great for me. (libraries and debugging are also a plus feature) Why should someone stick on the Arduino IDE?

[@glewiss6696]

What stm32 libraires would you use then on platformio ? Thanks

[@AndreasSpiess]

Same question here

[@namesurname5005]

@@AndreasSpiess Sorry, i just saw your response! platformio.org/lib/search?query=platform%253Aststm32&page=1

[@rcpoisond]

Regarding ESP32 ADC, have you tried measuring using battery? A quick test shows that I get very stable values when running my ESP32 from a battery and measuring the battery via a voltage divider compared running/measuring from a DPH5005. Maybe the noise is because the ADCs have a much lower sampling time and thus pick up the power supply noise?

[@AndreasSpiess]

Battery is always good to reduce noise. I used USB for all my tests. Also reducing the sample rate helps a lot. Did you check the linearity?

[@rcpoisond]

@@AndreasSpiess 'Plotted' a graph a while backand it matches what other people found. it's mostly linear between 0.3 and 3V. Of course since I did it manually it's low resolution. Currently hacking my DPH so I can automate stuff like this ^^

[@FearedSpark]

I use STM32 MCUs for most of my projects because of the awesome HAL. They are very capable chips, but as for every other chip, the Arduino library is limiting their capabilities (to the advantage of making them more accessible). I only use the ESP32 when I need the WiFI connectivity. The chip tested here is one of the first Cortex-M they released back in 2007. I think a better comparison would be with a STM32F4 series. As for development boards, several people already pointed out the awesome NUCLEO boards, the large ones coming with Arduino compatible headers, and integrated ST-LINK and serial port via USB. They also have a smaller form factor called the NUCLEO-32 if compared with an Arduino Nano.

[@FearedSpark]

As for the libraries, you should check PlatformIO, a little more complicated than Arduino, but has an ever growing support

[@AndreasSpiess]

1. I agree that I used an old chip. But most of the comments mentioned this Bluepill because it seems to be very common. I should get F4 blackpills and eventually will use one in a future video. 2. The only problem I have with Nucleo boards is their availability here. I have to go through digikey or mouser which doubles their price because of freight :-( Then they are as expensive as a Raspberry Pi.

[@ami6packs]

Stm32 dma feature is quite useful. I don't know if esp32 has this.

[@AndreasSpiess]

I also do mot know if their DMA features are comparable

[@TristanGomez]

I've been playing around with the NRF52832 and the low power BLE capabilities mean I can have it running on coin cells without much problems! It's the younger brother (sister?) of the NRF52840 found in the new Arduino Nano 33 BLE and also programmable with the Arduino IDE. I'd love to see more of the this Nordic Semiconductor chip in your videos :)

[@AndreasSpiess]

Me too!

[@jpjude68]

if i remember correctly, (from forun/errata sheets), the stm32's may have trouble with the ADC due to the integrated PLL which is used to generate the cpu's 72MHz from a simple 8MHz source. Also, it depends how the micocontroller is set at startup : the default configuration is 8MHz cpu clock without PLL.

[@AndreasSpiess]

Good information. I did not know.