TTGO ESP32 rev1 (rev one) Dev Module WiFi & Bluetooth 4MB Flash

Power Pins

GND - this is the common ground for all power and logic

BAT - this is the positive voltage to/from the JST jack for the optional Lipoly battery

USB - this is the positive voltage to/from the micro USB jack if connected

EN - this is the 3.3V regulator's enable pin. It's pulled up, so connect to ground to disable the 3.3V regulator

3V - this is the output from the 3.3V regulator. The regulator can supply 500mA peak but half of that is drawn by the ESP32, and it's a fairly power-hungry chip. So if you need a ton of power for stuff like LEDs, motors, etc. Use the USB or BAT pins, and an additional regulator

Logic pins

This is the general purpose I/O pin set for the microcontroller. All logic is 3.3V

The ESP32 runs on 3.3V power and logic, and unless otherwise specified, GPIO pins are not 5V safe!

Serial pins

RX and TX are the additional Serial1 pins, and are not connected to the USB/Serial converter. That means you can use them to connect to UART-devices like GPS's, fingerprint sensors, etc.

The TX pin is the output from the module. The RX pin is the input into the module. Both are 3.3V logic

I2C & SPI pins

You can use the ESP32 to control I2C and SPI devices, sensors, outputs, etc. If using with Arduino, the standard Wire and SPI devices work as you'd expect!

Note that the I2C pins do not have pullup resistors already! You must add them if you want to communicate with an I2C device

GPIO & Analog Pins

There are tons of GPIO and analog inputs available to you for connecting LEDs, buttons, switches, sensors, etc. Here's the remaining pins available.

Bottom row:

A0 - this is an analog input A0 and also an analog output DAC2. It can also be used as a GPIO #26

A1 - this is an analog input A1 and also an analog output DAC1. It can also be used as a GPIO #25

A2 - this is an analog input A2 and also GPI #34. Note it is not an output-capable pin!

A3 - this is an analog input A3 and also GPI #39. Note it is not an output-capable pin!

A4 - this is an analog input A4 and also GPIO #36

A5 - this is an analog input A5 and also GPIO #4

21 - General purpose IO pin #21

Top row:

13 - This is GPIO #13 and also an analog input A12. It's also connected to the red LED next to the USB portIt's also connected to the red LED next to the USB port

12 - This is GPIO #12 and also an analog input A11. This pin has a pull-down resistor built into it, we recommend using it as an output only, or making sure that the pull-down is not affected during boot.

27 - This is GPIO #27 and also an analog input A10

33 - This is GPIO #33 and also an analog input A9. It can also be used to connect a 32 KHz crystal.

15 - This is GPIO #15 and also an analog input A8

32 - This is GPIO #32 and also an analog input A7. It can also be used to connect a 32 KHz crystal.

14 - This is GPIO #15 and also an analog input A6

http://www.silabs.com/products/development-tools/software/usb-to-uart-bridge-vcp-drivers

Here are ：https://espressif.com/en/products/hardware/esp32/overview

240 MHz dual core Tensilica LX6 microcontroller with 600 DMIPS

Integrated 520 KB SRAM

Integrated 802.11b/g/n HT40 Wi-Fi transceiver, baseband, stack and LWIP

Integrated dual mode Bluetooth (classic and BLE)

4 MByte flash

On-board PCB antenna

Ultra-low noise analog amplifier

Hall sensor

10x capacitive touch interface

32 kHz crystal oscillator

3 x UARTs (only two are configured by default in the Feather Arduino IDE support, one UART is used for bootloading/debug)

2 x I2C (only one is configured by default in the Feather Arduino IDE support)

12 x ADC input channels

2 x I2S Audio

2 x DAC

PWM/timer input/output available on every GPIO pin

OpenOCD debug interface with 32 kB TRAX buffer

SDIO master/slave 50 MHz

SD-card interface support