SparkFun ESP32 Thing

Hardware Overview

Espressif's ESP32 is one of the most unique microcontrollers on the market. Its laundry list of features include:

• Dual-core Tensilica LX6 microprocessor
• Up to 240MHz clock frequency
• 520kB internal SRAM
• Integrated 802.11 BGN WiFi transceiver
• 2.2 to 3.6V operating range
• 2.5 µA sleep current under hibernation
• 32 GPIO
• 10-electrode capacitive touch support
• Hardware accelerated encryption (AES, SHA2, ECC, RSA-4096)

The ESP32 Thing is designed to surround the ESP32 with everything necessary to run and program the microcontroller, plus a few extra goodies to take advantage of the chip's unique features.

Peripherals and I/O

The ESP32 features your standard fare of hardware peripherals, including:

• 18 analog-to-digital converter (ADC) channels
• 3 SPI interfaces
• 3 UART interfaces
• Two I2C interfaces
• 16 PWM outputs
• 2 digital-to-analog converters (DAC)
• Two I2S interfaces

And, thanks to the chip's pin multiplexing feature, those peripherals can be connected to just about any of the 28 broken out I/O pins. That means you decide which pins are RX, TX, MISO, MOSI, SCLK, SDA, SCL, etc.

There are, however, a few hardware features -- namely the ADC and DAC -- which are assigned static pins. The graphical reference below helps demonstrate where you can find those peripherals (click to embiggen!).