ESP32-DevKitC V4 is a small development board based on ESP32 by Espressif. Most of the pins of the modules on the board have been led out. Developers can easily connect multiple peripheral devices through jumpers according to actual needs, or develop the board is used on the breadboard.
EN: Reset button.
Boot: Download button. Press and hold the Boot button, and press the EN button (do not release the Boot button at this time) to enter the “firmware download” mode and download the firmware through the serial port.
USB-to-UART Bridge | A single-chip USB-UART bridge that can provide transfer rates up to 3 Mbps. : Micro USB port
USB interface: It can be used as the power supply of the circuit board, or the communication interface between the PC and the ESP32-WROOM-32 module.
5V Power On LED: When the development board is powered on (USB or external 5 V), this indicator will light up.
I/O: Most of the pins of the module on the board have been led to the header of the development board. Users can program ESP32 to realize various functions such as PWM, ADC, DAC, I2C, I2S, SPI and so on.
Pins D0, D1, D2, D3, CMD and CLK are used for internal communication between the ESP32 chip and the SPI flash, and are concentrated on the two sides of the development board near the USB port. Generally speaking, these pins should not be connected, otherwise it may affect the operation of SPI flash / SPI RAM.
Pins GPIO16 and GPIO17 are only applicable to the onboard ESP32-WROOM series and ESP32-SOLO-1 development boards, reserved for internal use.
The development board can choose one of the following three power supply modes:
Micro USB power supply (default)
5V / GND pin power supply
3V3 / GND pin power supply