ESP32-DevKitC-32UE Development Board

Arrived relatively on time. Both seem to be working fine. The ESP32 has a lot of features: SPI tested OK, SDIO tested OK, I2C tested OK, UART tested OK, WiFI OK. Something to look out for is that its fuses were different from the original DevKitC boards. In my opinion, because these boards come pre-built with SPI flash, then the respective fuses should have been pre-burned so that you don't get strapping pin issues with your SD-Card. The thing seems to be working fine. They are GREAT, feature-filled little development boards for the price. (There is a learning curve for the ESP-IDF development, but the NET is full of tutorials.) They are more expensive from Amazon (double or more), but at $11.00, the price is still good for what you get. I'm very pleased with them so far.

These are amazing products for the price. I've owned several of the ESP32-DevkitC-32U, and I read those are obsolete for new development, so I bought this one instead. I was disappointed that I had to hold the reset button to get the program to start once power was applied. I know there are fixes online for that, but I just added an exterior pushbutton that connects EN and GND momentarily. I power it on and press the button and it works. The ESP32 isn't accessible in my project, so this works for me. Anyway, I love the external antenna for projects that connect to WiFi.

Got this to fork from my Arduino hobby into a board with embedded comms. Haven't tested Bluetooth yet but wifi works really well. So far it's everything I hoped for, have built several test projects and it nailed them. Long term, this board or another like it will power a system that monitors cycle time on a 240v mechanical system and uploads to a cloud DB with a grafana dashboard with out of compliance alerting. Good stuff.

Update: Some developers might be better off avoiding the WROVER based DevKitC boards. This goes for all DevKitC boards with WROVER's on them, not just ones from this seller. Several of the exposed pins are useless for general development purposes. For example, pins 17/18 (which many ESP32 developers might know as the default UART2) are unusable on this board with a WROVER. Several of the pins near the USB connector also have reserved uses that can make them annoying to use. For more information, check the Espressif technical documentation on ESP32-DevKitC. You could save a tiny bit of money buying a 3rd party ESP32 board. Then realize you have to press/hold buttons to flash anything, or that you have to flash bootloaders. Then some things don't quite work the right way... Or, just get a real Espressif board to begin with and know that everything works the way it's supposed to. Sometimes it's nice when things just work... It doesn't hurt that it's using the newest WROVER variant of ESP32 with PSRAM, etc.

These are pricey but they are the standard. They worked as advertised and I use these first when developing projects because they have the fewest bugs. Once I figure out exactly how something will operate and have already written the code, I switch to smaller or cheaper boards. If a project isn't working using another ESP32, try this one and see if it 'just works'.

I stumbled across a tutorial written several years ago by a guy in Germany who wanted to build a device that would report the humidity in several rooms in his basement through an Amazon Echo (Alexa) device. His tutorial didn't quite work for me, but it gave me a lot of good hints on how to start. I was able to build three devices that use this board and a DHT22 temperature and humidity sensor that will report temperature and humidity in different locations through an Alexa skill I wrote. Then I extended the skill and the code that runs on the ESP32 to add control of an AC solid state relay with a DC control input. The Mongoose-OS software made the ESP32 side easy. I wish I could say figuring out how to write the Alexa skill was as easy.

The construction and feel of the board feels of high quality. Sturdy and you can really see the number on the GPIOS. It comes with exactly 0 in the way of docs but you can find info online. NOTE: it does fit on a standard mini bread board BUT you ONLY get ONE row of free GPIO pins! You will need to 'smoosh' 2 mini boards together after pulling apart their power rails. I love that this has 4 MB of ram. I *thought* it had 8 MB (my bad) . But really happy so far regardless, it's day one. EDIT 1/2024: What goes on in the AMZN warehouse? It got smooshed on delivery!

Replaced a different one that I fried and works as intended.