ESP32-DevKitC-VIE Development Board

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.

These are much better quality than ESP32 boards that I have purchased from other manufacturers. This should be expected as these are made by the same company that manufactures the ESP32 chip. These work very well with ESPHome. I am using them with an ultrasonic sensor to determine car position in my garage.

This is the new ESP32-DevKitc_V4-VIE development board from Espressif. It has only been available for purchase for a few months. It is the latest iteration of the WROVER models that have the additional 8 megabytes of PSRAM (but only 4 MB can currently be used). Until now I have only seen these Espressif development boards offered with 4 megabytes of program flash memory. This model has double that -- 8 MB! So twice the memory and an extra 4 MB of usable PSRAM!To see details of the different ESP32s, google "Espressif Product Ordering Information." Based on that source, this WROVER-VIE uses the new ESP32-D0WD-V3 chip. It has an IPEX (ergo the "I" in "VIE") connector for an external antenna, as well as an onboard PCB antenna that is disabled. It is possible to convert it to use the onboard antenna, but that involves doing some micro-soldering to remove a tiny 0 ohm resistor and add a tiny solder bridge. So if you want to use the onboard antenna, I strongly suggest you order the VE (no "I") version that Amazon sells for the same price: https://www.amazon.com/Espressif-ESP32-DevKitC-VE-Development-Board/dp/B087TNPQCVHere is an example of an external antenna that works well https://www.amazon.com/gp/product/B01KBU61S8Features:240 Mhz CPU (configurable)80 Mhz Flash (configurable)IPEX connector for external antenna (buy the “VE” version if you want to use the onboard PCB antenna)OTA upgradeablePROs:Great price – only $11.008 Megabytes of flash memory8 Megabytes of PSRAM (but only 4 Megabytes can be used)Quality buildDoes not require that you manually put it in boot loader mode before flashingCONs:Due to its width, when installed in a breadboard, only one row of exposed pin sockets are availableI have used multiple models of the Espressif Esp32-devkitc_v4 development boards in the past and have been happy with them all. This one is my new favorite.

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 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.

I have no idea why this ESP32 board isn't the most popular on Amazon. It's priced competitively, and it's an official implementation straight from the manufacturer. Since its OEM, the board works perfectly out of the box, unlike some other ESP32 implementations from other companies. No soldering caps across EN/GND (HiLetGo ESP32 uploading issue) or 3.3/GND (KeeYees ESP32 wifi issue). The silkscreen is also printed on the top of the board like any same human being would want, as well as the bottom.The only caveat is that the picture is incorrect like another review has said. This board uses the WROOM chip with the 4 MB memory, not the 8 MB of the WROVER chip. The model is correct though.

The chip works fine and programs like any other esp32. But the manufacturer made some fatal mistake here. There is literally no WiFi range. I can only communicate with it if it’s sitting on top of my laptop and it’s in ap mode. It will not even try to connect to my router unless I set it atop my router. I think they forgot to solder the antenna to the chip.

This is a blue tooth interface, but much more. It is a development kit for dirt cheap. It has a powerful processor, a low power processor, a blue tooth interface and a wi-fi interface. The processor has A/Ds, D/As, PWM ports, digital inputs, digital outputs, timers and a USB interface. This $10 module has it all.