DFRobot FireBeetle ESP32-E Manual page 7

Port Pin: the default physical pin number of the chip, which can be directly used to control the corresponding pin
IDE: In Arduino IDE, the pin numbers have been remapped by FireBeetle, or you can directly use this symbol to control the corresponding
pin
RTC PIN: FireBeetle supports low power function, and in deepsleep mode, only RTC pins can be used.
Power: FireBeetle leads out the power source voltage and the voltage stablized 3.3V power supply through pins, which is convenient for
users to use.
GND: FireBeetle common ground pin
Power
GND: common ground for all power and logic
VCC: positive voltage of USB/li-ion battery input(5V-output USB voltage when powered by USB; 3.7V-Output battery voltage when
powered by Li-ion battery)
3V3: output of 3.3 voltage regulator, can provide 500mA peak current
Control
RST: connected to the reset pin of ESP32, can reset program
EN: enable pin of 3.3V voltage regulator. It has been pulled up, so grounding can disable the 3.3V regulator.
GPIO
D2 to D13: these are general purpose pins, which are usually used as digital pins or multiplexed function
A0 to A4: these are analog input pins, of which A0-A3 can only be used as input pins.
SDA-IIC(line) data pin
SCL-IIC(line) clock pin
SCK/MOSI/MISO: hardware SPI pins, you can use them as normal GPIO pins (but it is recommended to leave them idle as they are best
suited for high-speed SPI hardware)