#embeddeddevelopment

Metro RP2350 take 5 🔄🌟🤞

The ESP32 has completely transformed the world of DIY electronics and IoT development. From smart home automation and wireless sensor networks to robotics, industrial monitoring, AI edge devices, and wearable electronics, ESP32 boards are now powering millions of connected projects worldwide.

One of the biggest reasons behind this popularity is the massive variety of ESP32 boards available today. What started as a simple Wi-Fi + Bluetooth microcontroller family has now evolved into an entire ecosystem of specialized chips and development boards optimized for different applications.

But with so many variants available - ESP32 DevKit, ESP32-C3, ESP32-S2, ESP32-S3, ESP32-H2, WROOM, WROVER, PICO, TTGO, T-Display, T-Beam, and dozens more - selecting the right board for an IoT project can quickly become overwhelming.

This guide breaks down the major ESP32 families, their strengths, weaknesses, and ideal use cases so you can choose the perfect board for your next project.

Why ESP32 Boards Are So Popular?

ESP32 boards combine several features that previously required multiple separate components:

Built-in Wi-Fi

Bluetooth Classic + BLE

Dual-core processing

Low power operation

Rich GPIO support

ADC, DAC, PWM, SPI, I2C, UART

Affordable pricing

Massive software ecosystem

Unlike older Arduino boards that required external Wi-Fi modules, ESP32 boards integrate wireless connectivity directly into the MCU. This dramatically simplifies IoT development while reducing cost and complexity.

The platform also supports multiple development environments including:

Arduino IDE

ESP-IDF

PlatformIO

MicroPython

FreeRTOS

CircuitPython

Because of this flexibility, ESP32 has become the default choice for both beginners and professional embedded developers.

Understanding the ESP32 Ecosystem

The term “ESP32” does not refer to a single board.

Instead, it represents an entire family of microcontrollers and modules developed by Espressif Systems. Different versions are optimized for different tasks like ultra-low power sensing, AI processing, USB applications, display interfacing, or mesh networking.

The ecosystem can broadly be divided into:

Classic ESP32 Series

ESP32-C Series

ESP32-S Series

ESP32-H Series

Specialized Display & LoRa Boards

Compact Mini Boards

Industrial & AIoT Boards

Each category serves different IoT requirements.

Classic ESP32 Boards

ESP32 DevKit V1

The ESP32 DevKit V1 remains the most widely used ESP32 board in the maker community.

It typically uses the ESP32-WROOM-32 module and offers:

Dual-core Xtensa processor

Wi-Fi + Bluetooth

Around 30 GPIO pins

ADC, DAC, PWM, Touch Sensors

Excellent community support

This board is perfect for:

Smart home projects

MQTT communication

Wireless automation

Sensor interfacing

Robotics

IoT learning

For beginners, this is still the safest and most versatile starting point.

ESP32 DevKit V4

The V4 boards are newer revisions with improved power regulation, better USB interfaces, and more stable designs.

They are commonly used in:

Commercial prototyping

Stable USB communication projects

Long-running IoT deployments

ESP32-WROOM-32

This is technically the module used on many development boards.

It contains:

ESP32 chip

Flash memory

RF circuitry

PCB antenna

Manufacturers build custom development boards around this module.

It is widely used for:

Custom PCB designs

Embedded products

Production-ready IoT hardware

ESP32-WROVER

The WROVER series adds PSRAM.

This extra memory is extremely useful for:

Camera applications

TFT displays

Audio processing

AI workloads

Buffer-intensive applications

If your project involves graphics or large data handling, WROVER boards are significantly better than standard WROOM modules.

ESP32-C Series

The ESP32-C series is focused on low power and cost optimization.

ESP32-C3

The ESP32-C3 is one of the most important modern ESP32 variants.

Key features include:

RISC-V architecture

Wi-Fi + BLE 5

Lower power consumption

Improved security

Compact form factor

These boards are excellent for:

Battery-powered sensors

Portable IoT devices

BLE beacons

Smart locks

Energy-efficient nodes

ESP32-C3 boards are rapidly replacing older ESP8266-based designs.

ESP32-C6

The ESP32-C6 introduces major wireless upgrades including:

Wi-Fi 6

BLE 5

Zigbee

Thread support

This makes it ideal for next-generation smart home ecosystems.

C6 boards are becoming increasingly important for Matter-compatible devices and advanced mesh networking applications.

ESP32-S Series

The S-series focuses on USB functionality, AI acceleration, and advanced peripherals.

ESP32-S2

The ESP32-S2 is a single-core processor with native USB support.

It is useful for:

USB gadgets

HID devices

Keyboard emulation

USB automation tools

Secure IoT applications

Although it lacks Bluetooth, it offers strong security features and stable USB integration.

ESP32-S3

The ESP32-S3 is currently one of the most powerful and versatile ESP32 variants available.

Features include:

Dual-core Xtensa LX7

Vector instructions for AI

Native USB

Improved GPIO handling

Better display support

Enhanced BLE capabilities

ESP32-S3 boards are ideal for:

AIoT devices

Voice recognition

Edge machine learning

Smart displays

Camera projects

LVGL GUI applications

Many modern display development boards now use ESP32-S3 chips.

ESP32-H Series

The H-series is optimized for low-power mesh communication.

ESP32-H2

The ESP32-H2 supports:

Zigbee

Thread

BLE 5.2

Unlike most ESP32 variants, it does not include Wi-Fi.

This board is designed specifically for:

Matter devices

Smart home ecosystems

Mesh sensor networks

Industrial automation

As smart home standards evolve, ESP32-H2 boards are expected to become increasingly important.

Compact ESP32 Boards

Miniature ESP32 boards are becoming extremely popular for embedded and wearable projects.

ESP32-C3 Super Mini

Despite its tiny size, this board still provides:

Wi-Fi

BLE

GPIO support

USB programming

It is excellent for:

Wearables

Mini robots

Compact sensors

DIY gadgets

Portable electronics

These boards are especially useful when PCB space is limited.

ESP32-PICO-D4

The PICO series integrates:

MCU

Flash

Passive components

into a single compact package.

This simplifies PCB design and reduces external component count.

Perfect for:

Production devices

Space-constrained designs

Consumer electronics

Display-Based ESP32 Boards

ESP32 display boards are becoming increasingly popular for modern IoT interfaces.

TTGO T-Display

This board combines:

ESP32 MCU

Built-in TFT display

USB interface

Compact design

It is widely used for:

IoT dashboards

Smart clocks

Portable monitoring systems

Cyberdeck projects

Data visualization

LilyGO T-Display S3

The S3 versions offer:

Better processing power

Improved graphics handling

USB-C connectivity

Larger display compatibility

Excellent for LVGL GUI development and smart interfaces.

M5Stack Series

M5Stack boards are modular ESP32 systems designed for rapid prototyping.

They often include:

Displays

Batteries

Sensors

Expansion ports

Grove connectivity

Popular in:

Industrial prototyping

STEM education

Rapid IoT deployment

LoRa ESP32 Boards

LoRa-enabled ESP32 boards combine Wi-Fi with long-range wireless communication.

TTGO T-Beam

The T-Beam includes:

ESP32

LoRa radio

GPS module

Battery management

Perfect for:

GPS tracking

Remote monitoring

Mesh communication

Off-grid IoT systems

These boards are heavily used in Meshtastic projects.

Heltec WiFi LoRa 32

One of the most popular LoRa ESP32 boards.

Features include:

OLED display

LoRa radio

Compact size

USB programming

Excellent for remote sensor nodes and wireless telemetry systems.

Which ESP32 Board Is Best for Beginners?

For beginners, the best overall choice is still the ESP32 DevKit V1.

Why?

Because it offers:

Huge community support

Endless tutorials

Stable performance

Low cost

Easy sensor interfacing

Excellent compatibility

It remains the easiest entry point into IoT development.

Best ESP32 Boards for Different Applications

Best for General IoT

ESP32 DevKit V1

Best for Low Power Projects

ESP32-C3

Best for AI and Smart Displays

ESP32-S3

Best for Matter & Zigbee

ESP32-C6 / ESP32-H2

Best for Wearables

ESP32-C3 Super Mini

Best for LoRa Projects

TTGO T-Beam

Best for GUI Interfaces

LilyGO T-Display S3

Best for Camera Projects

ESP32-WROVER

Final Thoughts

The ESP32 ecosystem has grown far beyond a simple Wi-Fi development board. It now includes specialized platforms for AI, low-power sensing, display interfaces, LoRa communication, Zigbee networking, USB devices, and industrial automation.

The “best” ESP32 board ultimately depends on your exact application requirements.

If you are just starting your IoT journey, an ESP32 DevKit board is still the most practical option. But as projects become more advanced, newer boards like the ESP32-S3, C6, and H2 unlock entirely new possibilities in edge AI, Matter networking, and next-generation wireless communication.

No matter which board you choose, the ESP32 family remains one of the most powerful, flexible, and affordable platforms available for modern IoT development.

In today's interconnected world, Bluetooth technology meets not only audio transmission needs but also plays a key role in data transfer. The KT1025A chip offers excellent Bluetooth data transmission features, supporting two main modes: BLE and SPP.

BLE Transparent Transmission: A Power-Efficient Solution

Designed for low-power applications, BLE is ideal for devices requiring long operation times with minimal power consumption. KT1025A supports standard BLE data transmission, ensuring stable connections and data interaction between devices. This makes it a top choice for smart home and health monitoring devices.

SPP Transparent Transmission: A Classic and Reliable Option

Based on the classic Bluetooth protocol, SPP provides higher data transfer rates and stability. It's perfect for applications needing fast and reliable data transmission, such as industrial control and medical data collection.

Flexibility and Reliability in Data Transmission

Whether using BLE or SPP mode, KT1025A ensures efficient and reliable data transmission. The built-in protocol stack handles the complexities of Bluetooth connections, allowing developers to focus on application development.

Practical Application Cases

In smart home systems, KT1025A can connect various sensors and controllers via BLE for seamless communication. In medical devices, SPP mode can transmit high-precision monitoring data, ensuring accuracy and timeliness.

Conclusion

Fruit Jam RP2350B credit-card mini computer with all the fixin's 🍓🍇💾

We were catching up on a recent Hackaday hackchat with Eben Upton (https://hackaday.io/event/202122-raspberry-pi-hack-chat-with-eben-upton) and learned some fun facts: such as the DVI hack for the RP2040 was inspired by a device called the IchigoJam (https://www.hackster.io/news/ichigojam-combines-strawberry-and-raspberry-to-deliver-a-raspberry-pi-pico-powered-educational-micro-66aa5d2f6eec). We remember reading about this back when it was an LPC1114, now it uses an RP2040. Well, we're wrapping up the Metro RP2350 (https://www.adafruit.com/product/6003), and lately, we've been joking around that with DVI output and USB Host support via bit-banged PIO, you could sorta build a little stand-alone computer. Well, one pear-green-tea-fueled-afternoon later we tried our hand at designing a 'credit card sized' computer - that's 3.375" x 2.125", about the same size as a business card (https://hackaday.com/2024/05/07/the-2024-business-card-challenge-starts-now/) and turns out there's even a standard named for it: ISO/IEC 7810 ID-1 (https://www.iso.org/standard/70483.html).

Anyhow, with the extra pins of the QFN-80 RP2350B, we're able to jam a ridonkulous amount of hardware into this shape: RP2350B dual 150MHz Cortex M33 w/ PicoProbe debug port, 16 MB Flash + 8 MB PSRAM, USB type C for bootloading/USB client, Micro SD card with SPI or SDIO, DVI output on the HSTX port, I2S stereo headphone + mono speaker via the TLV320DAC3100 (https://www.digikey.com/en/products/detail/texas-instruments/tlv320dac3100irhbt/2353656), 2-port USB type A hub for both keyboard and mouse or game controllers, chunky on-off switch, Stemma QT I2C + Stemma classic JST 3-pin, EYESPI for TFT displays, 5x NeoPixels, 3x tactile switches, and a 16-pin socket header with 10 A/D GPIO + 5V/3V/GND power pins. The PSRAM will help when we want to do things like run emulations that we need to store in fast RAM access, and it will also let us use the main SRAM as the DVI video buffer.

"See" the Sounds of Classic Mac Audio 🔊🍏

We're working on the Pico-Mac port https://github.com/jepler/pico-mac/tree/rp2350-fruitjam to Fruit Jam https://www.adafruit.com/product/6200 and one thing we really want to add is sound support for classic Mac games and HyperCard stacks.

Espressif programmer test success! 💻✨🔧

While developing boards, there are oftentimes we want to program ESP chips without going through the onboard USB port; this adapter will help us (and others) do that! It has a CP2102N USB-serial chip

https://www.digikey.com/short/bm7n3p5z

...with RX/TX signal LEDs and two transistors wired up to the DTR/RTS line for the 'esptool standard' reset procedure technique. The output IO, plus a 3.3V 500mA regulated output, is available on a socket header, so you can plug wires in for quick programming and debugging. You can use this for everything from an ESP8266 up to the ESP32-P4! Here, we are testing it with a HUZZAH ESP8266 breakout board

Bus Pirate 5 is in stock and shipping now, going fast! 🚌 🏴‍☠️

Bus Pirate 5 is the latest edition of the original universal serial interface trusted by hackers since 2008. We've stocked and loved the Bus Pirate 4 for years and are excited to see the latest and greatest from the minds at WhereLabs.

The Bus Pirate is a RP2040 based, open-source hardware debugging tool that converts simple commands into common bus protocols such as 1-Wire, I2C, SPI, UART, several LEDs and more. Send commands to a chip or sensor and get the response, without writing a line of code.

Feather RP2350 boards are being tested and are close to shipping 🪶🍇

Our RP2350 Feather design is finally inching closer to release in the adafruit shop - having fixed a clock delay bug that was causing 50% of our boards to not boot, we've now got the tester working well and able to program and test boards in about 8 seconds. Now that we know the hardware is in good shape, we'll fabricate more and get this first set of 150 pieces into the shop. sign up to get first dibs!