KeeYees ESP32S ESP32 Development Board 2.4 GHz Dual Core WLAN WiFi + Bluetooth 2-in-1 Microcontroller ESP-WROOM-32 Chip for Arduino (38PIN Narrow Version, 2PCS)

I just received my first two this afternoon, and uploaded several sketches to both. They work just fine. I like the little sticky tapes with the pin names on them. A few tips:1) For those that complain about pressing the right-hand button to start an upload in the Arduino UI, this is very common, not a quirk in these particular boards. Not a big deal, really. Watch your sketch compile, then when it starts to upload, press the right-hand "boot" button for a few seconds. In my case, I hold the button until I see upload progress start, then let go. Nothing to it.2) The on-board blue LED is connected to D2, by the way. Try the "blink" sketch first, and just change the default pin name or number to 2 instead of whatever the sketch default is.3) When deciding what flavor of ESP32 board to select in the Arduino UI, I just use the generic "ESP32 Dev Module" and everything works fine for me. I have several other ESP32 modules, like the WROOM, and they all work with the Dev Module selection for me. Easy.4) I also tried the very simple Wi-Fi server that can flash the on-board LED (no external connections needed) by going to Examples/WiFi/SimpleWiFiServer. Change the default pin 5 to pin 2 in several places, and then put in your home Wi-Fi SSID and your password. Enable the serial monitor for 115200 bps, and upload it. Once it connects, the ESP32 will tell you what its IP address is. Enter that IP address (like 192.168.1.123) in your phone or computer web browser, and you'll get a simple page coming from your ESP32 (which is now an HTTP server). The page tells you something like "click here to turn LED D2 on" (assuming you edited your sketch so that it says "D2" instead of D5) and a similar line to turn the LED off. Nothing to it, and you did this with zero hardware!5) My modules did not have any labeling or silkscreen on them, but the included sticky labels are just fine. I stuck one set on the bottom of one module, and on the connector edge of the other. They are sticky enough that I'm not worried about them falling off.I really like these units, and will definitely buy more! I also bought a pair of the KeeYees breakout boards with screw terminals, and they perfectly match the pinout of these 38pin modules.

I had to install the CP210x USB-to-serial driver to get Windows 10 to see the device on a COM port. Also, when the Arduino IDE started trying to upload my program to the board, when the IDE output said "Connecting...", I had to press the right pushbutton on the board, for a couple of seconds, in order to allow uploading to occur. Other than those two not-serious gotchas, the board seems to work as expected. (I tested getting chip info, doing an http get via WiFi, and deep sleep with timer wakeup.) The chip is reported as model ESP32-D0WDQ6 Rev 1. Both boards work fine.Update 2022-11-23: I bought two more boards for a total of four. All 4 have functioned well without any known reliability problems. (I'm using WiFi, digital GPIO usage, internal LED, flash updates, NVS changes.) THESE THINGS ARE GREAT!Update 2022-12-08: I bought two more boards. 6 out of 6 have worked flawlessly. I wrote custom motion sensor software using PlatformIO...flashing from PlatformIO works flawlessly OTA or wired. Every pinout has behaved as expected.Update 2024-10-13: I've purchased five batches of 2 boards (10 boards in total) over the past two years, and all of them have worked flawlessly. They are 38-pin narrow boards (25.4mm/1in wide), unlike many of the other boards that are 2.54mm/.1in wider than this one. So these fit nicely on a 400 point breadboard, leaving a usable wire point adjacent to each pin on both sides of the board after it's been seated into the breadboard. They have 4MB of flash storage. Excellent quality/value.

I got these to replace some nearly identical ones from a different seller which had super flaky wifi (it turned out due to counterfeit USB chip leaking high voltage to the ESP32). I'm happy to report that, despite having a no-name USB chip (CP2102 clone, I think) all the voltages measure as they should (unlike the other brand) and the units work so far flawlessly. I bought these from KeeYees this time because I had purchased some ESP8266s from them a long time ago which have worked great for years, and so far it looks like their ESP32s are similarly well-enough made.So, if you are scratching your head over which brand of this board to buy when there seem to be so many that are exactly the same: Beware they may be the same design but the components matter, and so far for me at least KeeYees has sent me good, working boards, spanning multiple years, which I can't say for some other random brands/sellers.

So far, mine have worked well. My only complaints are that the pin outs don’t match another ESP-32 developer board and, in particular, the diagrams left me worried about Vin5V pin. As with Arduino boards, my other ESP32 board had a 5V pin which directly connected to the USB 5V. This design allowed me to use it to either power the board or to power small loads. This meant that I could develop safely through the USB or with one power supply: Plug it into USB and the 5V powers the devices, plug a 5V into it and that powers my devices and USB. Here, it’s not so clear whether I can draw a small current through that pin. So I’m keeping it powered with the 5V power supply AND the USB while I’m developing.