#Guide: Which ESP32 development board to choose to develop DIY connected objects

After the success of the Wi-Fi ESP8266 modules, Espressif has not stopped in such a good way and today offers us its successor the ESP32. The first development board based on the SoC ESP-WROOM-32 very often exceeded €15. Since the beginning of 2017, prices have fallen sharply. It is no longer rare to find maps for about €7 / $8 (postage included). It’s happy because the competition is tough against the Raspberry Pi Zero W offers around €11. The ESP32 offer is now very diversified. Here is a brief overview.

New models ESP32 2018

Just like the ESP8266 which is now called ESP8266EX or ESP-WROOM-02, Espressif has completely revised its range of ESP32 WiFi chips at the end of 2017. The 2018 range now has 6 models. The ESP-WROOM-32 module will probably be the most widely used module for development board manufacturers for the general public and DIY projects. The ESP32-WROVER module is also available for sale.

Module Description Puce Dimensions (mm) Pins Flash (MB) PSRAM (MB) Antenne
ESP-WROOM-32 integrates ESP32 SoC, flash memory, sensors and PCB antenna with good RF performance

Technical documentation

ESP32-D0WDQ6 18×25.5×2.8 38 4 N/A PCB
ESP32-WROOM-32D integrates an ESP32-D0WD SoC. It targets a wide variety of applications, sensor networks, voice encoding, music streaming and MP3 decoding

Technical documentation

ESP32-D0WD 18×25.5×3.1 38 4 N/A PCB
ESP32-WROOM-32U integrates an ESP32-D0WD SoC. It is equipped with an IPEX U.FL connector

Technical documentation

ESP32-D0WD 18×19.2×3.2 38 4 N/A IPEX
ESP32-WROVER has both an external 4 MB SPI flash memory and an external 4 MB PSRAM

Technical documentation

ESP32-D0WDQ6 18×31.4×3.3 38 4 4 PCB
ESP32-WROVER-I has an IPEX antenna. The module has an external SPI flash memory of 4 MB and an external PSRAM of 4 MB

Technical documentation

ESP32-D0WDQ6 18×31.4×3.3 38 4 4 IPEX
ESP32-PICO-D4 is a System-in-Package (SiP) module in a single box.

Technical documentation

ESP32 7.0×7.0x0.94 48 4 N/A N/A

In addition to these 6 models, Espressif has developed a mono-core processor clocked at 160MHz that will be available in 2018. This module referenced ESP32-SOLO-1 incorporates the main technical features of the ESP32 modules. This less powerful module should also be less energy intensive, so better suited for battery-powered applications.

  • WiFi antenna power: +19.5 dBm
  • Bluetooth BLE with L2CAP support, SDP, GAP, SMP, AVDTP, AVCTP, A2DP (SNK) and AVRCP (CT)
  • Standby current is less than 5 μA
  • Equipped with the same devices as other ESP32 modules: Capacitive Touchscreen Support, Hall Sensor, Low Noise Amplifiers, SD Card Interface, Ethernet, High Speed SPI, UART, I2S and I2C
  • CE and FCC certified

Technical Specifications of ESP-WROOM-32 Modules

Before going any further, a brief reminder of the technical characteristics (official document) of the ESP-WROOM-32 module. It is the ESP32 module that is most commonly used in development board manufacturers.

  • ESP32 Module: ESP-WROOM-32 from Espressive.
    • Microprocessor dual core @ 240 MHz
    • 4MB flash memory
  • Connectivity
    • WiFi 802.11 b / g / n compliant with IEEE 802.11 compatible with WFA, WPA / WPA2 and WAPI
    • Bluetooth 4.0 LE and BR / EDR
  • I/O
    • 26x Digital I/O (3.3V)
    • 12x analog inputs
    • 4 × SPI, 2 × I²S, 2 × I²C, 3 × UART, CAN 2.0, IR, Touch Sensor,
    • Temperature sensor
  • Cryptographic protection: AES, SHA-2, RSA, ECC, random number generator (RNG)

Here is also the general identification of the pins. As you can see, unlike the Arduino, almost all pins support the Pulse Width Modulation (PWM). On the other hand no evolution regarding the input voltage and output, it is always 3.3V.

ESP32 espressif Pinout broche esp-wroom-32

Generic ESP32 boards: Geekcreit, Doit

There are some at all prices. Can not test them all. We can just rely on the opinions left by buyers. However, Geekcreit is now a recognized manufacturer. We also find his board under the name MUST recently. The Geekcreit is equipped with a micro-USB connector for power, programming and debugging. It is very well supported by the Espressive SDK. The ESP32 Generic Module must be chosen. It is available for the price of €8,07 excl. It is very often promoted for about €7.

esp32 geekcreit wroom

 

Full selection of generic ESP32 development boards

Known manufacturers: Wemos, SparkFun

If you prefer to stay on familiar terrain, the major board manufacturers now offer boards based on the ESP-WROOM-32 module. The latest is the Wemos LoLin32 presented in this article. It is an excellent choice. Equipped with 4MB of memory and a micro USB connector for programming, it is narrow and equipped with an external LiPo battery connector. It is supported natively by the Espressive SDK. It is available for the price of €6,45 + shipping (8,10 € in my case). This is much cheaper than the SparkFun ESP32 Thing.

wemos lolin32 esp-wroom-32 espressif top view

In the same category Hornbill, an Indian manufacturer launched a Crowd Funding campaign recently and offers the ESP32 Dev

Hornbill ESP32 Dev

Full selection of Wemos LoLin32 development board

Full selection of Wemos LoLin32 Lite (more compact) development board

Specific ESP32 development boards

Interesting news, this board-based ESP32 combined with an OLED screen SSD1306 (tutorial). It comes with an expansion board with 10 connectors that appear to be in Intel Grove format. The board is sold under the Wemos brand and moreover it seems to be recognized as such by the SDK. It is offered for about €12,80 (+ €2,21 postage).

esp32 wemos lolin32 oled grove intel 1 esp32 wemos lolin32 oled grove intel 2

This board sold under the name of LoLin ESP32 is available with several expansion boards: DHT11, DHT22, button, LiPo battery 18650 …

Full selection of ESP32 development board with SSD1306 OLED display

ESP32 board development for objects connected to the LoRaWan network

The LoRaWan network makes it possible to connect objects (sensors, actuators) or machines without going through a local WiFi network, ADSL or fiber. If you need to develop applications that use the LoRa network, there are now very economical development boards based on ESP32. Development boards are usually equipped with an OLED screen driven for an SSD1306 circuit.

Choose the radio module that corresponds to the frequency used in your country. Each radio module can be configured in a particular frequency. There is an optimal frequency for each module.

Module Frequency Best performance
Semtech SX1272 863-870 MHz (Europe)

902-928 MHz (US)

Semtech SX1278 Band2(LF): 410 ~525MhzBand3(LF): 137 ~175Mhz 433Mhz
Semtech SX1276 Band1(HF): 862 ~1020Mhz 868Mhz
Semtech SX1276 Band1(HF): 862 ~1020Mhz 915MHz

The complete selection of ESP32 development boards with LoRaWan SX1276 or SX1278 radio module

Sources : 

http://wiki.dragino.com/index.php?title=LoRa_Questions

https://www.libelium.com/forum/viewtopic.php?f=29&t=17198

Compact ESP32 boards

If the compactness of the development board is paramount for your project, there are very compact boards. Let us not forget that the ESP32 also incorporates Bluetooth, which makes it possible to make less expensive and more compact setups than starting from an Arduino nano V3 combined with a Bluetooth module HC-06. An HC-06 Bluetooth module alone costs 50% of an ESP32 development boards!

In this area, DIY MORE markets this board for example, which measures approximately 2cm side for about €17.90.

esp32 diy more development board

Less expensive (€6,90), the LoLin ESP32 is an equivalent of the Wemos d1 Mini. It is sold alone or in kit for €45 including a double base, shield DHT11, DHT22, relay, 4x LED WS2812B, 12x Led ring light, proto

lolin esp32 wemos kit

If you do not have a problem with the weld, nothing prevents you from going on the ESP32 + adapter module. We can find kits starting from 5,90 € approximately. Attention to the module, very often it is an ESP-32S which is delivered in the kit.

esp32s adapter board

Full selection of compact ESP32 development board

Build your PCB and integrate an ESP32 module

If you want to develop your own circuits (PCB), nothing prevents you from the ESP32 module alone. A good online circuit design software such as EasyEDA and it’s gone! The module can be found only from about €5 .

esp-wroom-32 esp32s module

Full selection of soldering module ESP32

Program ESP32 modules with Arduino IDE

The ESP32 introduces some changes in the programming. It took a while for the main bookstores to be adapted to run on the new Espressif SoC. Today, it is almost as easy to program an ESP32 as an ESP8266 with Arduino code. Read this tutorial to start programming ESP32 modules with the Arduino IDE (on Windows, macOS or Linux).

ide arduino esp32 demo led blink geekcreit

To go further, here are the latest articles and projects based on ESP32

Program ESP32 modules with PlatformIO

The PlatformIO editor also supports C ++ application development with built-in Arduino libraries. This code editor is very interesting if you want to share code with different micro-controllers. PlatformIO is also able to update the program remotely (including via internet). This feature that requires a paid subscription is for companies that develop sensor fleets. A limited use for Makers (Community version) is however proposed (50 update monthly, prices in detail here). To start with PlatformIO, it’s here. I advise you to install the PlatformIO plugin on VSCode, Microsoft Visual Studio Code open source code editor, lighter than Atom from GitHub.

visual studio code platformio home screen

Develop connected objects without programming with ESP Easy Mega (version 2)

The ESP Easy team is also working on adapting the firmware for the ESP32 modules. For now, it only works (very well) on the Wemos LoLin32 Lite. It is a little restrictive but it is an excellent development board to test absolutely. To learn more, you can read this full review, the opportunity to discover also the new features of the Mega version.

Subscribe to the weekly newsletter

No spam and no other use will be made of your email. You can unsubscribe anytime.

DIY Projects