ESP32 Programming Tutorial for Custom Hardware (GPIO, Serial, SPI, WiFi) - Phil's Lab #91

How to write firmware for custom ESP32-based hardware. Example features an ESP32-C3 MCU with QSPI flash memory, SPI inertial measurement unit (sensor), USB, LEDs, and PCB antenna (WiFi). PCBs by PCBWay www.pcbway.com
Board bring-up using the Arduino IDE for simplicity.
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[LINKS]
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[TIMESTAMPS]
00:00 Introduction
02:02 Altium Designer Free Trial
02:27 PCBWay
03:04 Hardware Overview
05:30 Arduino IDE Set-Up for ESP32
06:35 Board Set-Up
09:00 Flashing Firmware
10:27 LED GPIOs
12:57 USB Serial
14:02 SPI Sensor Interface, Basic Set-Up
18:34 SPI Protocol Basics, Read Register Implementation
24:50 SPI Test (Chip ID and Temperature Sensor)
28:06 WiFi Test (Basic Server to Toggle LED)
31:12 Outro

[@nathanwiebe935]

Please do create a video showcasing your non-Arduino IDE/debugging workflow! Many (like me) who use IDEs and debuggers but are newer to ESP32 would be infinitely grateful, and many people who have only ever used Arduino will have their minds blown how quickly high quality code can be written and debugged so quickly with a proper debugger. Esspressif's own videos get outdated very quickly, and don't show a real walkthrough from start to finish, and it would be good to see a real developer demonstrate.

[@PhilsLab]

Thanks, Nathan! Definitely will make a video on that for ESP32. I have some already on STM32-based boards on the channel with a 'proper' IDE and debugger - using a debugger is infinitely helpful, as you say.

[@markhaskins840]

@@PhilsLab I would be interested in this also, starting 2or 3 projects this year at work all fit the esp32 well I need to get familiar with vs code / idf also they are in stock so I can spec something that can be purchaed in quantites... always a bonus nowadays!

[@RafaGmod]

I agree with you! The most common platform is use PlatformIO on VScode. Nowadays, the arduino IDE > 2.x uses VScode instead of that old proprietary inteface! It got realy better, but plaftformIO on vscode can do more, lige debugging and OTA updates. yes! Is crazy that the ESP32 runs a little "RTOS alike" inside so it can use the Wifi modem of the main program to get ota updates. It's a little different than some microcontrollers that we code the entire program and also thats the cause for it to take so long to compile!

[@jj74qformerlyjailbreak3]

I spent 2 hours trying to setup Expressifs IDE, IDF, and toolkit. That process made me fall in love with Arduino.

[@bitbanggaming204]

I'd be interested. I use the esp idf a ton but it's nice to see someone else's workflow. I do not use platform io as I think it's better to understand esp32 without it.

[@McReaL44]

I am a last year mechanical engineering student. In our finishing project, we needed to design mechatronic part too. For that part, I have designed pcb just by watching your videos and with kicad. I have learned a lot of things from you. Thank you Phil!

[@PhilsLab]

Thanks, Cem - that's great, congrats on making the PCB as well! Good luck with your final project :)

[@MikeHarris1984]

Your series is flat out amazing!!!! Thank you for this!!!! I couldn't find anything for the SOC ESP32. Only the prebuilt controller board and the solder that on. I wanted to step it up a notch and do my own and not a bunch of soldered PCBs on my own board. And going through tech design docs and all that from esspresif, I was 90% there and your series helped me get that final hump complete while teaching myself

[@fredflickinger643]

Thank you Phil for the this comprehensive series on the ESP32!

[@PhilsLab]

Thanks for watching, Fred!

[@michalpesko5598]

A video about ESP-IDF setup would actually be great!

[@andrew48dhs]

Thank you, just thank you. This tutorial is a lifesaver for a project Im working on right now and many more projects in the future

[@PhilsLab]

Very glad to hear that, Andrew!

[@andrewturnbull7690]

Excellent video, right pace, very clear and concise, ideal for a rusty old retired engineer like me to think about dipping my toe into electronics once again.

[@matteopoggiali6100]

If you will make a comparison between espressif and Arduino IDE I think It would be very appreciated, one of most viewed about this topic for sure

[@Stabby666]

The Espressif IDE is not fun. It would probably take an entire video just for the installation process - along with debugging why it doesn't work the first 10 times you try installting it. 🤣 I have tried using it and returned to Arduino. I only use it now to test libs that I convert to use with Arduino.

[@tarantula_live]

@@Stabby666 Do you use with VS Code plugin? It makes it pretty simple and debugging works

[@PhilsLab]

Thanks, Matteo - will be making a video on that in the near future!

[@zyghom]

@@Stabby666 installation is not a big deal even if it takes you 5h as it is done only once the bigger issue is: something what you can do in 3 lines of code in Arduino framework, will require 25 lines of code in Espressif framework for every piece of code

[@davidchamberlain1513]

@@Stabby666 that must be why I can't seem to get the Espressif IDF and Visual Code working, I've only tried it 5 or 6 times...

[@dyn01234567]

I would love to see you doing this with VSCode and ESP-IDF! I've tried editing other microcontroller code in VSCode before - it can be very challenging to setup, but if you can get it working, it is the most fluid development experience in my opinion. I'd also like to know what you think of PlatformIO plugin for VSCode.

[@mathhack8647]

Really Amazing. this how any engineer should read Components References.

[@Alberto0352]

Your videos are amazing I'm learning a lot from them, thank you for sharing this! The fact that you start from scratch is awesome, you explain everything in detail. You should make more series about designing esp32, stm32 and perhaps pic32 embedded hardware from scratch and how to program them with professional IDEs. Here are some ideas I'd be interest seeing in your videos: - designing full speed USB-C hardware - communication between multiple microcontrollers - interfacing an embedded system with a pc (maybe with a GUI) - some IoT application (WiFi and BLE) - talking more about FPGAs and how to program them.

[@PhilsLab]

Thank you very much, Alberto! Thanks also for the great video suggestions.

[@pietrogagliano4484]

Awesome content as always Phil!

[@PhilsLab]

Thanks, Pietro :)

[@UmairAhmadh]

Thank You! If you are doing something more on this, please consider writing firmware for a custom IC that has different clocks and signals to get the function working. For example, TLC5957 LED controller IC. That'll give a lot of knowledge on firmware.

[@oreovios306]

So thorough 👌🏾

[@Jose13T]

Thanks for all the tutorials and tips on PCBs! I would like a video of programing the ESP32 with VSCode and if its possible some debug with breakpoints and seeig the variables in running time. Again thanks for your awesome content!

[@sergeyp6941]

Thank you! I would really like to see projects on Xilinx working with NAND, PCI and flow control

[@pete3897]

World have been interesting to print the RSSI out and compare it to a standarised module in the same location on the same network (plus RSSI of both from the other end). I ponder the legal requirements one might have using a non pre-certified RF implementation in a commercial product. Excellent video 👍

[@PattysLab]

Up to that 100K awesome tutorial as always!

[@PhilsLab]

Thank you! Fingers crossed!

[@den19980107]

this is a good video! thanks alot!

[@sanjikaneki6226]

Great video again! Will you also make a video on how to use a more pro environment? like ESP-IDF wit ESP IDE or VScode using ESP-IDF ? Asking since Arduino IDE feels limiting and often at the mercy of what libraries are them.

[@midhunvr7236]

Great video. Thanks

[@tonygiguere2495]

And again like always great video :)

[@PhilsLab]

Thanks, Tony!

[@thedrunknmunky6571]

I use PlatformIO on VSCode to program my ESP32 projects. As I’m yet to get an in-line debugger working with it, I’d appreciate any videos in that regard.

[@Graham_Wideman]

Point of clarification regarding "Pins" for those unfamiliar with the Arduino IDE. Arduino libraries that interact with I/O often require a "Pin Number" argument. WIth an actual Arduino, that argument corresponds to the I/O pin numbers printed on the board. Of course, within the Arduino hardware description files, those pin numbers are mapped to particular bits on particular ports. So, for example, on ATMEGA328-based boards, the hardware config file maps "Pin 0" to Port D, bit 0, which, on the hardware is brought to a connector where it is labeled "0", and so on. But... For boards that are not actual Arduinos, like Phil's board, there is no existing reason for any particular physical I/O or GPIO to be any particular "Arduino pin number". So it's up to someone to create a board definition that maps Arduino library "Pin numbers" to GPIOs. It's quite convenient that the libraries Phil used just map Ardunio numbers to the same-number GPI0, but that's not required, and can be changed. Anyhow, this discussion explains why Phil named his constants Xxx_PIN, after just explaining that these are _not_hardware pin numbers. Instead, they are for use as "Arduino pin numbers" in functions that require such an argument, and rely on the mapping described above to interact with the desired GPIOs.

[@dasloki5598]

Brilliant work Phil and a great help. Would be great to see a video using the Espressif IDE for a custom made board, and would very much like to see how to use FreeRTOS to for example run the accelerometer/gyro on 1 core, and save the data on SD card or transmit via BT using the other core.

[@PhilsLab]

Thank you! I'll be making a video on IDF at some point (even though it's a slight pain in the rear end in my eyes).

[@muzairafzal1529]

Excellent content brother.....

[@PhilsLab]

Thank you!

[@mak22223]

Thank you, Phil, for your videos)

[@PhilsLab]

Thank you for watching :)

[@nicoladellino8124]

Very nice video, TNX Phil.

[@PhilsLab]

Thank you, Nicola!

[@steffenthun2076]

Hi Phil, great Tutorial. I planed to design my own PCB with Microcontroller, RF Communication and PWM DC Motorcontrol. Do you have experience with motorcontroller and RF Com on the same PCB?

[@larmaths9790]

great job, keep going you're awesome

[@PhilsLab]

Thank you!

[@th3magist3r]

Really awesome! Thank you for providing comments every step of the way. Could you please make a video for that PCIe interface of the custom FPGA?

[@PhilsLab]

Thank you, Alexandros! Right now I have a few projects going (incl. bringkng up the FPGA course board), so I'm not sure quite when I'll get round to the PCIe board I'm afraid..

[@ibrahimobaido]

Thanks for sharing 🙏🏻

[@PhilsLab]

Thanks for watching, Ibrahim!

[@mikey38632]

Great video! I have a newfound interest in microcontroller programming and found this video in my searches. Quick question: when setting up the on-chip wifi access point, can I make that SSID hidden? This is to keep the general public away. I may use my project in crowded event centers. Also, does the ESP32 detect and show hidden networks or keep them hidden?

[@nmjerry]

I'd like to see you setup, use and compare the idf framework

[@mitchelskees1937]

When selecting the board (06:50), plugging it in provided the board name automatically (09:15).

[@kzalesak4]

Subscribed. Perfect.

[@PhilsLab]

Many thanks!

[@drhubs7049]

Im ngl, where was this 6 months ago? 😈 Great material man, it was good to reinforce some of my knowledge and learn a thing or two 😁

[@PhilsLab]

Thank you very much!

[@StreuB1]

Well done, Phil. One of your best videos yet with regard to how you outlined what you were doing, why you were doing it, and the examples. Little quick when you were scrolling up and down through the code when going over SPI, but other than that it was brilliant. The SPI section and the simple section on reading the data sheet and using #define and WHY you were doing it was especially top tier. NO ONE EVER EXPLAINS #define!!!!! Thank you so much!!!! Any chance that you might do some work on a little bit of a lower level regarding SPLD's, like the ATF16V8B-15PU? FPGA's are an interest but far too esoteric for lots of us and the bar for entry is rather steep. I think starting off with a simple PLD using WinCUPL might be a nice little video series that viewers can use to get their feet wet. It is nice as well due to how cheap these PLD's are and that WinCUPL is free, old, and simple to understand for users who have no idea what fuses and the like even are. Thank you!!! 🙂

[@PhilsLab]

Thank you very much, Brian! I'll keep that in mind to go a bit slower when scrolling around for future videos. Not sure when/if I'll be covering PLDs I'm afraid. I only really make videos on things I use in my own projects or for work - if they do come up, I'll be sure to make a video though. Right now it's "just" been MCUs, FPGAs, SoCs, and so on.

[@StreuB1]

@@PhilsLab No worries on the speed, I can always pause and rewind. Though you seem like the type that doesn't mind feedback at times. Especially on some subtle areas. Understood on the content being project/work related. Completely understand that as it's easy (and relevant) to make content on what you're currently doing and interested in. I knew the chance was low and it might be a step backwards for you given the complexity of your projects. I would be remiss if I didn't at least ask. You're a great teacher and thought if someone could do a little intro on these and do it well, it would be you. Thanks again and look forward to the next video!! Your videos have really kindled my desire to start transitioning over to EE and software at work. When the opportunity comes up at least! 😁

[@hofertyp]

I'm woundering why this channel hasn't more subscribers. Coming from IT-Sec, would appreciate if you also do videos in that direction. eg safe communication with sensors and actuators. Also safe WiFi setup without saving the Wifi credentials locally. Thanks!

[@PhilsLab]

Thanks! I'm afraid my knowledge is rather limited w.r.t. safe comms, but if I ever dive deeper into that topic, I'll make videos on that as well.

[@Aludre]

nice video, I like the new playlist with esp32. How much current the board is use in Wifi mode. Maybe you can show the deep sleep function and its current usage?

[@Dazza_Doo]

I'm sorry I missed your first video, I'll be rewatching these. I have 5x ESP32-C3-Mini-1, a different type from yours, as it has the built in Antennae as a PCB. Thank you these will be invaluable. Have you considered doing a video on the OpenAi (ChatGPT). I attempted to use it for ESP32 programming, and while the Arduino interface are more examples, rather than complete code. I found it more useful to ask for code in Espressif (freeRtos) and PlatformIO. I haven't had anything successful with it, maybe you will have better luck. Interestingly I've been attempting to get the OTA working with FreeRtos and this isn't as simple as adding the Arduino ATO library. I also found the FreeRtos to be limited to C, while the Arduino allows for some C++

[@HolyPiyush]

Awesome information sir Just subscribed your channel ♥️🇮🇳♥️

[@PhilsLab]

Thank you, glad to have you here!

[@Biomancer81]

I would very much enjoy a video on non-arduino prgramming of esp32 based boards

[@berberger4814]

yeah please do the video on the toolchain that does not only use arduino ide, also can you maybe include some kind of display + a lib for it

[@AhmedAli-op6ng]

Hi phil i like your content. I have taken courses related to pcb designing and can design on various platforms but for testing i always use arduino ide but i am blank related to firmware or programming other boards. Please make more videos related to such topics.

[@PhilsLab]

Thanks, Ahmed! Will do :)

[@cigunrh]

Brilliant video. I desiged a pcb based on the esp32-c3-mini1. I added a uart connector.is it possibleto program the esp via an external ftdi and the uart connector?

[@andymouse]

I would love to see you use the ESP tools for programing...cheers. edit: great tutorial and would like to see more.

[@PhilsLab]

Thank you, Andy - will definitely be making on with the ESP tools!

[@NicksStuff]

27:15 I went down a rabbit hole after seeing your calculation...turns out you could shift accRegRead(0x08) one bit to the right: it's faster than multiplying by 0.5 and doesn't require to declare a constant as float

[@NotMarkKnopfler]

Just wondering if the BOM is available for viewing anywhere? I''m interested in part numbers for the bare ESP32 chip and also the passive components around the RF section. Many thanks.

[@NeuroMod]

I would like to see a comparison between your antenna and something else such as an ESP32-C3 module integrated antenna or your mobile phone. Just something that could be used as contrast.

[@youtubeviewer7077]

+1 for non-Arduino setup. Would be great to make it generic just using cross-platform tools like Makefiles and GCC toolchain on the command line, so it can easily be adapted to any IDE/editor on any platform.

[@CuriousMaker609]

Wish you had the pdf of the schematic in your repository to recreate your design with other PCB design tools.

[@kevinjypiter6445]

Thanks, Phil! These resources are great and please keep them coming! And yes, please make a video covering an IDE like VSCode or what you prefer for a professional workflow. I am independently making a product using the ESP32-C3, so my only resources are online. I would love to see how you create your own workflow and see what is recommended for professional standards. I have been using VSCode on my Mac but it has been somewhat temperamental but thankfully does what I need to.

[@PhilsLab]

Thank you, Kevin! Will definitely do that!

[@PattayaDriver]

Thank you so much!!! I also made a ESP32 self-made board with smd parts last month. It works well, but I was wondering why the serial Monitor not work, while I can upload code via serial. In your video I saw that I have to change in the Arduino IDE "USB CDC On Boot" from disable to enable. That was it!!! Now my board is perfect. Happy!

[@PhilsLab]

Glad to hear it helped!

[@Graham_Wideman]

Hahahaha... watching Phil bringing up a new board using Arduino IDE while taking a break from... bringing up a new board using Arduino IDE. 🙂

[@Ownedyou]

Great video! Anyone have any success getting BLE Long range (coded phy) to work? The example isn't very good...

[@rakol96]

You are doing great job, i really like to watch your's movies. Also your voice is so understandable even with my poor english ;) I have some questions, i hate float, in many cases there no need to use it. In this case, just multiple by 10 solved problem. Another thing, is that correct to firstlly initalize ie SPI and after set !CS pin? In my opinion, much safer method is firstly set pin direction and deactivate all CS pin and after that, initialize SPI peripheral. Pleas keep going your great job :) best regards from Poland

[@nevensky]

Very nice tutorial. But I too am worried about following the EMC dirrective. Would this be allowed in a commerical product, i.e. could you self-certify without "fear" or would you instead send it to a lab for proper EMC evaluation? I suppose that is not something you can do at home, i.e. without a proper anechoic chamber?

[@mikehughesdesigns]

How do you handle the antenna certification? (or is it not needed?)

[@jackparzick7711]

Is there any particular reason you chose SPI over I2C for the BMI055?

[@serggorod1423]

17:17 labelled point

[@Anukul_Anand1309]

@Phil's Lab we would like to see programming ESP32 using ESP-IDF. Arduino framework is very easy to setup and we don't use it when it comes to development.

[@robdavis3220]

would love to see the eclipse workthrough.

[@vladi_g]

I haven't watched your old videos yet. I wonder why a separate SPI memory chip is needed if the ESP32C3 chip has 32 megabits of built-in memory?

[@carlos.galhano]

I from Portugal, where can I get that ESP32? And I am just beginning with Arduino Uno, and I must have a temperature sensor DH to see with my phone. Do you have some tutorials with that? Thanks and great vídeo👍

[@martinchristiansson658]

If you are going to do a video about how to use other development IDEs I will watch. Vscode, kiel or other... Best Regards

[@mmrx428]

Did you install any bootloader into the esp32 chip? Or does it come with a pre-installed chip, thanks in advance 🙏

[@MegaTraxxas]

I also would like to see a video about using ESP IDF

[@fillempie1501]

Just curious. What is de RSSI with this PCB antenna? Until which distance the Wifi is still working?

[@dom1310df]

I would use PlatformIO rather than the Arduinio IDE. No messing around with the board manager. It still uses Arduino under the hood but gives a much more pleasant user experience via VSCode.

[@avinashsethu1447]

if i choose esp32 s3 chip then what is the board i need to select in Arduino IDE

[@riffshyperion]

Is there any reason you allocate the SPI class on the heap using new?

[@ulri-electronics]

Hey Phil, I don't know how far your job integrates with final product development and certification or if you're focussed on PCB design and firmware programming. In case you already participated in a whole product development workflow I'd be really grateful for a video describing certification process with e.g. FCC EMI checks. This is especially interesting as your new videos contain WiFi and PCB antennas onboard, so you have to have a look at certification while designing already, don't you? All in all another really interesting video with great and simply teached content. Thanks!

[@PhilsLab]

Hey Robin, Thanks! I'm planning on having an EMC/compliance expert on within the next couple of months, to talk about exactly that!

[@ulri-electronics]

@@PhilsLab That's great news. Really looking forward to this and any other upcoming videos! Kind greetings from Germany.

[@wouladjecabrelwen1006]

Damn you dead the game thank you Sir. It's been awhile while I'm sticked on your course

[@PhilsLab]

Thank you!

[@zerobow9413]

Cant get the C3 to work on win7 even with the latest comms driver [testing with M5 stamp C3U] I must be missing something !

[@panos26]

How did we get that we write the GPIO number in LED_PINs and not the pin number? What in the table of the datasheet "said" to do so?

[@maazsiddiqui6324]

can we do DMA in this project?

[@TheEmbeddedHobbyist]

I find it better to print out data values during testing in hex as its far easier to read and convert binary to hex in you head.

[@maximus6884]

Do we have to press the button each time we want to program?

[@MikeNugget]

Have you ever faced the need to update a firmware after shipping hardware to the customer? And how would you solve this problem?

[@ME-dg5np]

Is possibile to change the flash rom and solder 16 mb in esp32 s3 ? A tutorial Is possibile ?☀️🌈 Tks You are a true master ! 👍🌈

[@Quantum_Dots]

Love your video seriers I am learining a lot being a physics student,Im interested to see runing micro-ROS ESP32

[@PhilsLab]

Thank you, glad to hear that!

[@CuriousMaker609]

I didn't know micro-ROS was a thing.

[@danedwards_ee]

Have you considered making a discord or something for patreons?

[@Stabby666]

I use these ESP32 chips quite often on my custom boards - they're easy to source and offer a lot of power and peripherals for the price. I also just use the Arduino IDE for these parts as the IDF environment is so annoying to install and get working (e.g. it will not work if your user folder in Windows includes a space, and reinstalling often doesn't fix things as it doesn't overwrite various auto-generated config files from previous installs). There is also a lot more code and libs for Arduino - the Espressif IDE is nowhere near as accessible. Espressif also often break their libs, or at least break backward compatibility by changing function signatures, or even class and function names on a whim. For other manufacturers I do use their own IDEs when possible, but Espressif are really not doing a good job with theirs.

[@PhilsLab]

Agreed, the IDF is a pain in the rear end in comparison to set up.

[@velho6298]

Please do a video about the firmware development on more professional tools!

[@PhilsLab]

Will do!

[@Interelectronix]

Dear Phil what IDE would you use to program the ESP32 that is more professional then the Arduino IDE ?

[@PhilsLab]

Hi Christian, I'd go for VSCode or alternatively Eclipse with the Espressif IDF.

[@Interelectronix]

@@PhilsLab thank you

[@shahinhaque95]

How come you switched from JLCPCB to PCBWAY? is there any advantage for this? ie Cost/Quality etc?

[@PhilsLab]

PCBWay offers more advanced PCBs (layer count, clearances, HDI, ...) and a more custom assembly service.

[@stevensexton5801]

Phil, Do you plan on uploading your HW design files to GitHub? If so, can they be imported into KiCad?

[@PhilsLab]

Yeah, I'll push the files to Git tomorrow. I think KiCad has an Altium importer of some sort - will need to check.

[@ligius3]

I'm wondering if the CDC somehow resets the chip automatically and selects the flash boot mode, or how does it work?

[@PhilsLab]

I believe so!

[@bramSDASCL1759]

How to encrypt the firmware using arduino ide?

[@frankbose544]

Yes show us the esspressif tools

[@keithsummers1889]

Arduino is the beginner's tool.... a hobbyist platform. A tool suited for targeting multiple hardware with one code base - maybe.

[@alpgenrobotics]

👏

[@gaborm4767]

Is it possible to order this board?

[@aarbtheorigin]

Hello, this is a beautiful design. I would like to hire you for a project involving a stm32. While I am quite good using kicad for schematics and PCB design, my knowledge regarding firmware coding is next to nothing. It would be beautifuly awesome collaborating with you. Thanks in advance.

[@ballboy2965]

Link to the datasheet pls

[@yellowcrescent]

Great video, as always. Yes, using VSCode and the native Espressive tools would be great. Especially for STM32, having a working GDB server and integrated programming and debugger is super handy, esp if you already use VSCode for other things. Eclipse seems to still be pretty popular for a lot of embedded C toolchains... but I try to avoid if possible.. lol.

[@leizhao1387]

cooooooool

[@gorkemsay]

Hi, When I try to upload empty sketch this error shows up "A fatal error occurred: Could not open COM19, the port doesn't exist ". I couldn't figure out what the problem is? Does anyone know?

[@gorkemsay]

I just realized that the board is rebooting continuously when I plug the usb cable. but why I don't know

[@gorkemsay]

If anyone face with this problem, replace 100n cap on boot pin with 1u and connect GPIO 8 to 3v3.

[@vogonjelc]

I must be stupid but I can't find video #90 with this board design.

[@Ajay-bk4xh]

@PhilsLab