Minimalist Microcontroller: Building a Bare-Bones Dev Board

I've been designing an ESP32-based dev board recently and I got to thinking - what's the minimum we can get away with and still have something that works? As always we're sponsored by www.PCBWay.com/?from=atomic.
Turns out that you don't need much at all, a pretty interesting experiment - though it did involve a lot of cursing as I tried to get stupidly tiny bits of wire soldered onto very tiny pads...
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[@atomic14]

The PCBs have arrived! kzbin.info/www/bejne/sJa2nYWseMlpqsk

[@AMATISIG]

It is recommended that the output capacitor be connected in series with a 0.5R resistor (or 1R is ok) can read TI slva115a file

[@OMNI_INFINITY]

Thanks for the tutorial! I feel relieved that it is that easy to design a board for an MCU! (or use it without needing a board) What are the pads on the bottom in the middle for?

[@Sovvyy]

It's surprisingly useful to know the bare-bones setup if you run into trouble when designing your own dev board :). Speaking from experience here....

[@atomic14]

Yeah - that was part of my inspiration - trouble shooting customer boards. Is it my board, the module, or just terrible soldering…

[@simonmasters3295]

Ah but look at what you've lost! WiFi,Bluetooth,accessible Pins,Clock,RAM,control of power... Love ESP32❤

[@Stabby666]

Note: You cannot reliably connect EN to the VCC without the resistor and capacitor, as the ESP32 can fail to boot/program if EN rises before the voltage is stable (the reason for the resistor and cap is to delay EN going high). I've tried this shortcut on PCB designs and it /may/ work for you, or may not. For a couple of pence in parts, it's not worth the risk.

[@atomic14]

Definitely agree - the PCB I've got coming has everything on it - surprising what you can fit into a very small space!

[@meltonermeltoner]

hello @Stabby666 i seem to be have this (can fail to boot) issue . i added the 10k resistor on the EN pin and it appeared to improved the percentage of times esp 32 started the program. but afterwords i still had unreliable start up. Do you think the problem is that i should also add also add a 1μF capacitor as you recommend ... ? and if you know should i also install a 10k resistor also on the gpio0 ? my only requirement is for esp32 to always start when its provided with power. no need of usb serial or buttons or need to program it. i have the chip pre-programmed.

[@kennethkramer9615]

Agree. At power up, the cap is initially 0 V and the voltage across the cap steadily rises exponentially until the 3V3 applied is reached.

[@anon_y_mousse]

It still boggles my mind that these chips are basically used as toys now days and yet when I was a kid desktop computers weren't that powerful. Even more mind boggling is how little energy it takes to run them.

[@whattt-wc7gw]

Can I just say, you have absolutely saved my arse! Brilliant video, very easy to understand especially for a beginner and knowing how to setup a barebones no-nonsense esp has came in so much handy for me. I scoured everywhere and as of this moment, have not found a single tutorial better than this one. It gets straight to the point and explains beautifully exactly what you need to do. Not only have you earned my immense respect and thanks, but a sub. Thank you so much.

[@LordPhobos6502]

Oh hey! This video came up in my recommendations again!

[@Corebb]

You can also try the ESP32-S3 Mini Module and ESP32-C3 Mini Module, which are more tiny. I have tried the ESP32-C3 Mini Module for a tiny space project, i just has the same thought of your, just ignore the unncessary caps, and just connect D+ D- to PIN 18 & PIN 19. The S2,C3,S3 support USB-CDC,which make it possible, i really like this.

[@atomic14]

Ooh yes, I should have used a mini for my next project! That would have been a good challenge.

[@TD-er]

Yep, really LOVE those Seeed Studio XIAO - ESP32-C3 modules. They don't have anything other than an IPEX connector, 2 buttons and an USB-C connector on board. (apart from the encapsulated module) Since they also use an external antenna, the WiFi reception is also quite good.

[@atomic14]

Very nice. And really tiny! I am wondering if I should have gone with an external antenna for my PCB version.

[@philiphart6688]

I was just mulling over this selfsame question when contemplating the use of the ESP32-C3-WROOM for a bluetooth badge project. And this video provides all the answers. So, very many thanks for posting !!

[@SpinStar1956]

Great video! But may I offer a suggestion? I used to teach a solder-certification course for missiles,and in watching your soldering, I see your main difficulty is not using an external flux. The solder on your iron and components becomes oxidized leading to globing and lack of heat-conduction. I realize that many people forego flux because of the necessity for cleanup, but you would have a much easier time if you would add some. If you ‘flood-the-field’, you can use your existing iron tin, otherwise, with minimal flux, use new solder each time but added flux is still recommended. Anyway, appreciate your video and all your commenters. 😊

[@LordPhobos6502]

I tend to use one of those cheap 'no-clean' flux pens. It's quick n easy and gets me out of trouble... a lot.

[@AzaB2C]

Neat! Appreciate the ESP info and ideas!

[@SinanAkkoyun]

Definitely needed, how often I find myself wanting so solder a small circuit in air! Thank you!

[@harrypehkonen]

OMG! Just what I have been looking for (not that I put a lot of effort into searching)! I have some bare-bones ESP32s, but didn't know what to do with them. Thanks for the video!

[@filips7158]

The capacitors on the USB lines are not used for noisy signals but as ESD protection. There should be at least a nF range cap on every pin to protect it against transients.

[@muhammadshaheer8309]

So which capacitors he is using here?

[@filips7158]

@@muhammadshaheer8309 he is not using any, that is the issue. The capacitor type should be MLCC chip cap, X7R type dielectric.

[@muhammadshaheer8309]

@@filips7158 And of which values?

[@gordoncouger9648]

You make a clever demonstration of how robust the ESP-32 is. We will be running out of IP addresses again if we put them in toys. Some wire wrap wire would make your task much easier. A search on `Manhatten type prototyping` and 'dead bug prototypes` should give you some ideas to make building things like this easier. You are putting a great deal of faith in the quality of power of the USB port the ESP-32 -plugs onto. Many years of experience have shown me that filters and bypass capacitors on B+ are needed. I've also learned to put a bleeder resistor across the B+ on computer boards others are going to install. A slow sagging B+ voltage can cause problems with some SRAM and EPROM. There is no way to tell how others will use the thing you make.

[@nerddub]

"Dead Bug" protyping brings me back to 2006 making BEAM robots from Mark Tilden's original designs, man how time flies

[@jameshogge]

These shouldn't affect the IPv4 address space issue. They'll all be behind NAT on people's private networks

[@jgunther3398]

i like to use 30 gauge kynar wire wrapping wire for soldering up like this. it's just the right size. thanks for doing this, as is being said it's very handy for quickly insuring what components and connections are necessary

[@AndersNielsenAA]

If you feel like giving it another go, I suggest you scratch away the solder mask in opportune places and use the copper ground plane for ground connections - that should also give you enough rigidity to actually mount the USB connector straight to the module. Decoupling capacitors are not optional though. Under less than perfect conditions that suggestion will certainly get someone in trouble - eventually :)

[@yanhuang4911]

I remember datasheet says you should keep components away from antenna on both sides

[@atomic14]

Yes, there's definitely some compromises going on.

[@mav29]

perfect, thanks sir glad to have bumped on this video, since i have limited electronics knowledge specially with the composition of components this will definitely help me bigtime for some small project to be fabricated, again thanks

[@brandao.rafael]

I loved how you edited the "schematics" on top of the real life footage at 6:55. Sometimes is just those small edits that tangle the whole video together and makes it way simpler to understand what was your endgoal

[@atomic14]

Thanks - was a nice animation to make.

[@no_360scope9]

I really love this type of experimentation. Like maybe you do it for you or maybe you do it for us a little too, but I find this work, serves as a platform for people maybe like myself to create, aim higher. I could have tried to experiment on this type of work myself, but you did it for me! Thank you for this information, I will use it graciously and pursue it with higher ambitions on my project!

[@L2.Lagrange]

This is very helpful! A similar video showing minimum design for STM32 would also be great

[@DeadsupraEE3]

this was very entertaining (and meaningfully informative). thank you!

[@norlesh]

Work of art! was thinking if you started with four strands of ribbon cable and soldered those to the naked USB micro pins while everything was straight and aligned then you could route those wires easily without needing the additional break out board. 20/20 hindsight and all.

[@YoutubeBorkedMyOldHandle_why]

Interesting. About the USB connections, perhaps you could try soldering the wires first, and then crazy gluing the connector to the board.

[@atomic14]

Yeah - that would have made it a lot easier. Also using thinner wire would have been better.

[@YoutubeBorkedMyOldHandle_why]

@@atomic14 Way off topic, but ... Once upon a time, I bought an Atmel-Ice PCBA. This is the cheapest 'pcb version' of Atmel's programmer/debugger. (The damned thing still costs $135, but that's another story.) When it arrived, I was a bit shocked to realize that they used 1.27mm pitch headers and had provided nothing besides the board, not even a basic cable. And I had nothing lying around which would fit. So, I ordered some parts to make a cable, but in the meantime, I just wanted to plug the thing in and see it work. This is what I did: I found a tiny piece of copper foil, cleaned it and cut some tiny strips perhaps 2x5 mm each. Under a microscope I wrapped each of these strips around a sewing needle. I used some needle nose pliers to crimp them, so there was a tiny copper tube and a bit of excess copper which I cut off with some small scissors. I then 'very carefully' soldered tiny wires into each of these tubes. Turns out the tubes were still a bit large, so to make them fit on the pins, I needed to crimp them a bit more. 1 mm shrink wrap was too big, but not every pin was populated, so in a pinch I managed to make all the pins fit anyway. By no means perfect, but it did the job. Long story I know ... bottom line is: within about an hour or so, I had my debugger working, while gaining a certain amount of experience soldering tiny little parts. It's amazing what can be accomplished when necessity demands it.

[@ctrlaltdude]

An advantage to this is that deep sleep will probably work a lot better compared to a standard dev board. The components on a dev board usualy keep using power during deep sleep or prevent it. I'm going to try this.

[@atomic14]

Yes, you just need to use a better LDO than the AMS117. There are really nice modern ones that have really low quiescent current.

[@tobbleboii5988]

if conserving space is not an issue, buck converters work pretty good as well. They have a low quiecent current and additionally make full power operation alot more efficient

[@fire17102]

Really awesome ! Can you still use all the gpios? I was just thinking about a tiny ESP-based polytuner for the guitar - strum all strings at once, and see which needs to tune up or down.. At minimum we'd need - a tiny mic connected, running fft onboard, either 6 tiny rgb leds or a thumbnail sized screen, tiny battery with charging over usb, & a power button/capacitive touch. After all string are in tune, flash all leds as a success signal, and shutdown. I'd enable raw data transfer over BT so an app on the phone can see all the signals and frequencies together in detail in real time. Also through the app you can set/change tunings and instruments. Honestly I don't have any experience designing a board, and lack in electrical engineering. But I'll happily write the code :) Hope you're a musician haha Let me know if you like the idea and if you'd consider helping. Thanks a lot and all the best !

[@atomic14]

Yes, all the GPIOs are available - it's really just like a normal dev board. Unfortunately I don't have time for other project work, but I'd be really interested to hear how you get on.

[@jgunther3398]

i've done things a little like that. i'd suggest starting with one string. then apply what you've learned to the other strings individually. then try isolating one string in software when all strings are strummed. then finally go for it all if you still have a mind left :) maybe try to isolate all strings in a sequence. it will be hard to do what you described because of the different volumes and how the frequencies interfere, but i don't see anything that would make it impossible

[@marcus_w0]

Great Tutorial! Is there something similiar for the ESP32-C3 Modules? Does this also work with them?

[@kbongos]

wire wrap wire is nice to work with, get different colors to color code. Beware insulation melts very easy and can cross connect if not careful due to soldering and crossed wires. Have tried the magnet wire, that can work nice, it's typically a little too thin(hard to see, work with), am going to try a slightly larger from a different scrap solenoid with thicker wire. And it's free with some scrap parts. For glue try sprinkling some baking soda on with super glue and it sticks to anything, dries instantly, and produces rock hard results. A little strange to work with as you have to sprinkle baking soda, but it works and you can build up amazing rock hard structure. Interesting the newer esp32's you can do USB direct and get rid of the USB-uart chip, that just seemed silly to have on every dev board.

[@gearscodeandfire]

Dude you rule- this is another project that was exactly what i needed!

[@atomic14]

Thanks! What project are you working on?

[@gearscodeandfire]

@@atomic14 Hi! Pretty much everything I make has a New esp32 tucked away in it, and I'm currently working on a project where a small form factor will be critical, involving LEDs, vibratory motor, servo motor, and somehow being waterproof 😳 I've also been flirting with having my boards assembled SMD style instead of using through whole parts, and this was incredibly helpful for that (as well as your other videos)

[@tttuberc]

Love this video. Looks like this is a perfect fun way to get started with couple Wroom modules someone gave me

[@korean_dude6036]

It is quite fun to watch... Thank you

[@aviandragon1390]

Very neat project. Good of you to share. I'm sorry to pick nits, but watching the soldering bit gives me anxiety. Turn the heat up on your iron, and keep a nice clean tip. Always remember when soldering that (within reason) heat does not destroy components; exposure time destroys components.

[@jrapplefan2231]

Very, very, very good and clever tricks. Thanks.

[@akhurash]

I ended up designing a dev board with just the ESP32 C3 WROOM module. I needed access to all the pins for development at work. Surprisingly didn’t find much out there that breaks out all the pins.

[@therzook]

For wire connections in quick and dirty tasks that are not to be used next day I use cores from solid utp cable cat5 or 6. Also u can strip it twist 2 cores, wrap it couple of times around soldering cylinder and use twisted wires end as new soldering tip. Last one is old hack from my grandpa when nothing was available (apparently they had abundance of stripped wires and some source of heating, not always electrical)

[@Dazza_Doo]

I've read the comments. This is what I'm looking for. I think it's a brilliant project. Thanks for uploading. I have a jtag board, I would upload an OTA program and you can do away with the Jtag and USB.

[@diegoporras7769]

Amazing content!

[@rioferzz]

is this applicable for esp32WROOM 32E? I'm looking for minimum system for it on google, unfortunately didn't find it for exactly 32E

[@MikeHarris1984]

Why not use an ESP32-S3 chip direct and build the Flash, controllers, and full setup, instead of the Wroom Module? You can likely make it smaller as you dont need all that there too... if you build the use case to be specific, can squeeze as small as you want if you dont need all PIN outs/ins, only the ones you need for that project. But this is a cool idea with the capcom tape and just soldering it on, lol. I've been designing my projects to not use the Wroom module, but use the ESP32 SOC and building Flash, ant connector, etc... I've been going through the datasheets and building my circuit based on the info there and the final product looks freaking professional! I have not ordered yet to test... but its a LOT cheaper as the same board (125mm x 98mm) through JLC fully assembled with the flash/ESP32/Ant conn/crystal/all the resistors, capacitors, inductors, relays, screw terminals, fuse, etc. is about $8 a board. on a 20 board order. That is using their supplies and such. This is just the esimate when uploading all the files and board info, not final. and the quote for the wroom32 module (I didnt want to go with S3 because of some library short comings in the ESPHOME echosystem this board is used for, and I am patiently waiting for C6 as I want the Zigbee on Chip!!!!) for everything, but swap all the items instide the WROOM32 with one, was around $18 for a 20 board order. So I am very carefully going thru my design and check and double and double check about 15 more times before I push the purchase thru for my first test board. I have watched Phil's Lab on this very item he has up and an excellent walk thru, after I did my first draft. I'm not an electrical engineer, so this is my home hobby projects, and doing this as a puzzle for myself to perfect it and then just take that module block and put it on all my projects going fwd. Maybe save some money in the long run. Going to see about having them non-build it and get the parts myself and since its just me and not a full production, hand build all mine to save a few more bucks. But the pricees they offer for fully assembled with parts included is so freaking CHEAP, its hard not to..

[@PeetHobby]

Great video! Maybe buy some thin wire wrap wires; they're more suitable for this type of solder work.

[@Lamoboos223]

Does that connection work on esp32-c3-wroom-02 as well?

[@celiox23]

THANK YOU omg i've been struggling for so long trying to do just that

[@justinindustries2747]

Are the boot or reset buttons needed? To upload code I need the boot button.

[@fireworm91]

how did you manage those solderings? i am soldering and making so many prototypes but i have so many dead boards afterwards... could you explain me ho do you do it? i have tried high temp, low temp, quick and dirty, fast and clean, slow /../. anything...

[@atomic14]

For this board I had it assembled for me - PCBWay are quite affordable and there's also JLC. But you can easily do it yourself as well. Hand soldering components is tricky and you can get into quite a mess. I would recommend using solder paste and either a hot plate or a cheap hot air gun. It's also really worth getting a stencil when you order your PCBs.

[@TYGAMatt]

Where did you get the schematic? Also, no need to do the "hold boot and hit the reset" for uploading? Which is what I'm doing on an original ESP32 module and also a C3

[@atomic14]

Schematic came from the data sheet - www.espressif.com/sites/default/files/documentation/esp32-s3-wroom-1_wroom-1u_datasheet_en.pdf page 28. With the S3 you shouldn't need to do the boot reset dance. But people's experience seems to vary.

[@TYGAMatt]

@@atomic14 thanks for your reply. I actually did a bit of research and found it, and several other, but thanks anyway. Also looked at various schematics for the C3 and it seems that you can pretty much just hook a USB connector up to the D+ and D- pins of that one too. Jolly handy as the board has way too many pull ups and using an FTDI and stabbing buttons is boring. Keep up the great work! Cheers Matt

[@stickyfox]

Is it possible to power down the wireless devices, or better yet get a non-wireless version? I see a lot of new platforms coming out with built-in wireless, which is great.. but sometimes you do not want the RF environment of a wifi/BT device, and just want the microcontroller.

[@atomic14]

Sure - you don’t need to enable the wireless/Bluetooth. It doesn’t turn on unless you tell it to. There are ESP32 modules that don’t have the PCB antenna and just have a small connector for an external one so you can even save space. But, if you’re doing a project that doesn’t need wifi or Bluetooth then it might be worth looking at the RP2040 as an alternative.

[@atomic14]

You can subscribe to the atomic14 newsletter so you never miss out! atomic14.substack.com/ There's also the monthly Maker News - full of interesting titbits and videos: makernews.substack.com/ If you'd like to help support the channel and help me buy more nonsense - I have a Patreon page: www.patreon.com/atomic14 And if you're shopping on AliExpress or Amazon then if you click on these links I will get a little bit of affiliate money: Aliexpress - s.click.aliexpress.com/e/_Ac05mF Amazon - www.amazon.com/?tag=atomic14-20

[@bendtherules0]

Can you please share your Gerber file/Easyeda link for the custom board? That would be helpful.

[@atomic14]

@@bendtherules0 Check out the next video - kzbin.info/www/bejne/sJa2nYWseMlpqsk - links are in the description.

[@GargamelCZ]

I have several old WROOMs just collecting dust - does this work only with S3 or with any ESP32 module?

[@atomic14]

Only ones that have the USB interface built in - S2 and S3

[@andrekurniawan2121]

Can I use esp32 devkit v1? or do you have to use esp32 s3?. Thanks full

[@MatthewKanwisher]

Awesome video please do more

[@matthewvenn]

8:14 wobbbly! didn't you super glue that down too?

[@atomic14]

I tried - I think my superglue has gone off. Or it just down't like me.

[@KJ7JHN]

what are the values of the capacitors on the regulator please? Input and output respectively. Thank you for the video.

[@atomic14]

For this project I was just doing a proof of concept, so I used some fairly random values. The data sheet for the AMS117 that you are using will give you the exact value to use.

[@ddjazz]

Great project for the less adventurous take a look at the seeed xiao esp32 modules

[@wahyu_zx]

Thank you sir for granting my request to make this video

[@UNgineering]

this is a great setup for a one-off, but you might start getting weird brownouts or random errors without all the noise-cancelling cap's if you put this circuit in the field.

[@atomic14]

Yeah, it’s definitely not for production use.

[@muhammadshaheer8309]

Exactly what capacitors you used?

[@abcdefGaming38]

At 6:18 you mention a decoupling capacitor. Would you mind sharing which ones you used? 22uF, 10v?

[@atomic14]

I just used some random ones from my spare parts. For a real PCB, you would need 10uF for the AMS117 and then for the ESP32, you would need the decoupling capacitors it recommends, 22uF and 100nF.

[@abcdefGaming38]

@@atomic14 gracias

[@abcdefGaming38]

@@atomic14 10pf electrolytic cap decoupling I thought? Well whatever 😂

[@dzakysyaddad8901]

Did we need to flashing firmware to esp32 in first time ? Or it can be use after we buy it?

[@atomic14]

That's a really interesting question - I've personally not had issues with fresh ESP32s and have been able to flash them no problem. But I have had various times where I've had to manually put the module into download mode using GPIO0. So in my recent designs I've just included buttons as it's pretty unreliable. Sometimes you can just flash it no problem. And sometimes it just won't flash.

[@icarossavvides2641]

Suggest soldering the wires to the difficult component first i.e. the USB socket then gluing down?

[@atomic14]

That would have been a lot easier.

[@gamingknightly]

Nice video! Is it possible to do the same in a esp 12E module as well? Thanks in advance!

[@atomic14]

The 12E would need a USB to serial chip - so more components are required. But if you were happy to connect directly to the serial pins then you could definitely do a very minimal dev board.

[@gamingknightly]

​@@atomic14Can you please make a video on that too? Even a short will be really helpful. I had made a automatic pump controller with WiFi capabilities using esp8266 dev board. But to make the same project commercial it would be necessary to switch from the pcb that i made using perf-board to a fabricated pcb along with the esp 12e chip and not the board. I want to prototype this design so i may want the serial monitor and also want the esp 12e to be programmable inside the circuit itself. I would really appreciate any help or any other ideas to prototype my design into a pcb. Thanks in advance! Oh thanks for reply too.

[@GoatZilla]

That kapton tape job looked like a DIY flex PCB assembly.

[@metl_play]

I think you could upgrade the "free hand" version with a flex PCB, that way it would be less difficult to solder the micro USB and have anything in place. Maybe I try it out, at least in theory.

[@greg4367]

He has accomplished SO much, for SO long, with SO little, he'll next attempt to accomplish the infinite with the infinitesimal. I I think he'll do it.

[@maximal9857]

for what the build flags mean: -DARDUINO_USB_MODE probably enables usb support for arduino-adjacent microcontrollers -DARDUINO_USB_CDC_ON_BOOT is what tells the microcontroller to enable "USB Communication Device Class", which is the spec for sending plain serial over USB. and because of the "on boot" part, i assume there is some way to do this in code.

[@atomic14]

Thanks for the explanation!

[@wojciechbajon]

In fact, in many cases we overpay for devboards. Sure, it is worth having one, but mounting a working system with its use is a waste of. The only thing we need is the 3.3V regulator and the socket for convenient connection of the USB-UART board (For comfortable ones - for programming ESP -01. For hardcorers - an old laptop with a COM port). In all this confusion, the most pissed part is the part that the leaders are not 2.5 mm in the raster and you need to solve how to lead them to a standard protoyping plate. BTW: in your solution is bad - you cover anthena by usb port. (look to datashet, for recommended module placing) Best way is use more capton tape, and move it to bottom (if antena is on top) (or even move all elemnts to ESP cover.

[@atomic14]

Very true. Defnitely a bit of a compromise on the antenna. I've got a PCB coming so I'll do some tests to see how much of an impact it has. Inspired by looking at the TinyTV teardown (kzbin.info/www/bejne/rnKTYmd7q7pnfbc) I'm thinking of doing a new version with a vertically mounted USB socket. I'm also thinking there's plenty of room for MEMs microphone. And I think putting a connector for a display ribbon cable is easily doable as well.

[@jeanicezinho]

very nice!!!

[@TurtleWaxed]

The bare bones idea excellent, the soldering seems to need some help and maybe better flux and smaller diameter solder for the tight spots. Quite the challenge without very good solder equipment, I could feel your pain. :(

[@atomic14]

yeah, not ideal. Was surprised it actually worked.

[@mast3rbug]

You can do JTAG debugging directly with the USB port. No need to use the pins on the ESP32

[@Tavdog]

I would like to combine a max7219 based 32x8 led matrix board with an esp32. This really shows how minimal I could get it. Thanks.

[@atomic14]

Sounds like a great project.

[@szjoin992]

Great tutorial! The only remark from my side: You put a lot of stuff in the 'keep out area' (WiFi Antenna). I'd rather use the other side of the PCB for the USB connector. Thanks!

[@atomic14]

Very true - amazingly the wifi still seems to work. But definitely not recommended!

[@Alfi3boii]

when i hook up my esp32 to my pc it wont show up on my COM ports or as a USN device? any ideas ?:(

[@zyghom]

in all my projects I use bare-bone modules of ESP32 and its variants (Only prototyping I do sometimes on the dev boards). For many reasons: starting with power consumption of dev boards (too high), ending on customisations and money. However, SMD does NOT mean... flying components ;-) That is why you were not happy and successful

[@atomic14]

Very true, I've got a new PCB in the works - which is definitely my preferred option. But this seemed like a fun test of my fine motor skills - with predictable results!

[@Pein955]

Will this configuration work with esp32-wroom-32d?

[@atomic14]

You'll need one of the modules that has USB built in like the S2 or S3.

[@Pein955]

@@atomic14 thanks

[@taylor.galbraith]

Haha love it!

[@FiremarkPl]

So I guess, power usage should be minimal. Many devboards have problem with battery because of uart, usb and voltage converters. So it's what I looking for. Thanks!

[@TymArsenii]

does it work for regular esp32 (not s3)?

[@atomic14]

You would need to add a USB-UART IC for a regular ESP32.

[@sebby007]

You seem to really know your stuff. Very nice.

[@atomic14]

Still learning like everyone else.

[@AzaB2C]

Nice!

[@ngobduong8066]

I am new here think D+, D- from USB is 5V and esp32 s3 can support only 3.3v

[@JS7457]

I didn't even know you could program the esp32 with the USB otg port, is there a documentation talking about it?

[@atomic14]

Only the latest set of chips - support it, so the original ESP32 still need the USB-UART bridge.

[@JS7457]

@@atomic14 thanks, are those s2 and s3?

[@atomic14]

@@JS7457 that's right. One thing that is needed are the buttons for boot and reset. It seems that I can burn firmware 99% of the time without issue - and then randomly it will just stop working and I need to take IO0 low and reset it.

[@JS7457]

@@atomic14 thanks!

[@michalsabat4720]

you look like steve wozniak and steve jobs' faces fused together xD anyways nice vid! making it rn.

[@atomic14]

Haha - thanks! (I think :)). I've also been told I look a bit like the Edge from U2 - but that was when the beard wasn't quite a grey and was a bit more trimmed... Glad you enjoyed the video.

[@murraymadness4674]

Great idea if its a sunday night and you've got a demo to give monday morning, and your last working dev board got chewed by your dog. Otherwise, what is the point? You have all those pins how you going to connect to them? Can u buy plain esp32 dev boards to just solder your module. The bare modules are cheaper, I got a few S3's as the full boards are a few dollars more, and I've got some dead older esps, I assumed they are pin compatible with the s3, bet i'm wrong about that, anyway why I watched to see how minimum you can get, so thanks.

[@peut]

Next time,if ever, use thin enameled 'magnet wire'. As these are very thin, you hardly have to fight with other wires, and soldering is much faster as the wires are so thin.

[@jgunther3398]

30 gauge kynar wire wrapping wire is good -- plenty thin, durable insulation, usually silver plated and easy to solder to

[@peter.stimpel]

Nice. Did you measure the power consumption while having the "dev board" in deep sleep? Would love to learn about your DMM readings.

[@atomic14]

I didn’t! But that would be interesting. I think with a proper modern voltage regulator it should be very good.

[@peter.stimpel]

@@atomic14 Does the board still exist? Maybe you could ... ;)

[@atomic14]

Here you go :) kzbin.infoi4OT7duQy4M It's about 40mA when active and 5mA when sleeping - but that's probably almost entirely the AMS117 which has a quiescent current of up to 5mA!

[@peter.stimpel]

@@atomic14 Thanks a lot, Chris. That is what my assumption was. I run some ESP32 from LIFePos, without LDO and USB, and they consume microA while deep sleeping. But having USB and an VReg for updating and stuff would be convenient. I would have to add a jumper to disconnect the VReg when not using USB while running from the LiFePo, I guess. Again, thanks for confirming my thoughts.

[@hackswell]

@@atomic14 Not with an AMS117 regulator! Those things are power hogs! It has a Quiescent Current of 5_000 uA! Try something like the Ti TLV761 which has a quiescent current of around 65 uA, and still offers 3V3 at approx 1000 mA About US$0.66-0.75 each at Mouser.

[@der.Schtefan]

You can cherry pick an LED with a 1.7 Volt voltage drop. I think there are tools that allow you to search for which LED with which color has the highest probability to be EXACLTY 1.7 V. I have seen professional projects in the past abusing an LED for that.

[@atomic14]

Not a bad idea. Would certainly work for a low current circuit.

[@cowtaxi7451]

Where does a person buy a ams1117 33 d203 voltage regulator?

[@destiny_02]

it's easily available at any electronics store/website.

[@alejandroperez5368]

Because it's the one that most ESP32 dev board come out with. Hence, it can't be that bad

[@MOFUGGINFPV]

So I'm completely new to esp32 boards. I don't really understand most of this but I find it fascinating. I am however very familiar with Drone flight controllers, and the similarities between them is surprising.

[@atomic14]

Just having a look at some and they are pretty much the same as a lot of dev boards!

[@VidarrKerr]

OMG, What a Mess.

[@viktorhugo8252]

Why you don’t use a PCB for this work? The PCB with VDO and USB-Connector will not be much larger as the processor board.

[@atomic14]

Check out the next video in the series - kzbin.info/www/bejne/sJa2nYWseMlpqsk

[@viktorhugo8252]

@@atomic14 , I have seen your designed Dev Board, very good work. I can’t find any Board for ESP32-S3 only for processor and DVO and GPIO Connectors. I use this cheep board for ESP8266 and ESP32-WROOM with 16 MB.

[@circuitit4612]

always avoid mouting components on the antenna area

[@wilfredosandovaldelgado3690]

Guau... It's pretty.

[@Fixaj]

well if I test your viode on a new ESP32 S3 module (not replaced another ESP32 Board) it is NOT working. If I replaced another board esp32 s3 now working. SO i thing this this design needs a BOOT buton also. Otherwise this Error message appear on serial monitor : invalid header: 0xffffffff

[@atomic14]

Latest video with a fresh module seems to work out of the box - but I’m going to do some more experiments with more fresh modules straight from the packet.

[@OMNI_INFINITY]

Sad that I made an S3 board instead, because it hasn’t functioned properly yet. Got it to load in Windows, but it’s listed as “unknown” or similar. Guess that is logical because I designed the board. Would maybe try again, but it’s the f’ing cny festival now. Sigh…many chinese started vacation early and shipping from JLC was sadly EXTREMELY overpriced during cny. So maybe 10 or so days of no PCB orders. Sigh…

[@mathieusan]

if you remove the chip itself, since you can't program it anyway without the jtag, there you have it, back to nothing. Like the way I like it. Nice cause I started with nothing to do and ended up here

[@ressamendy]

It was a great challenge. A rabbit 🐇 came out of the hat.

[@gean7917]

Nice

[@kayakMike1000]

Oh. Its an S3...

[@Muss_._]

3:29 pentim

[@vkpc1]

Why most ESP32 modules contain a usb-serial chip if it was not required?

[@atomic14extras]

The original ESP32 module doesn’t have USB built in. Only the newer versions.

[@TheUnofficialMaker]

use wire wrap 30 ga wire