| Pin | Name | Function |
|---|---|---|
| 1 | EN | Enable / reset |
| 2 | GPIO36 (VP) | Input only, ADC1_CH0 |
| 3 | GPIO39 (VN) | Input only, ADC1_CH3 |
| 4 | GPIO34 | Input only, ADC1_CH6 |
| 5 | GPIO35 | Input only, ADC1_CH7 |
| 6 | GPIO32 | ADC1_CH4 |
| 7 | GPIO33 | ADC1_CH5 |
| 8 | GPIO25 | ADC2_CH8, DAC1 |
| 9 | GPIO26 | ADC2_CH9, DAC2 |
| 10 | GPIO27 | ADC2_CH7 |
| 11 | GPIO14 | ADC2_CH6, HSPI_CLK |
| 12 | GPIO12 | ADC2_CH5, strapping pin |
| 13 | GND | Ground |
| 14 | GPIO13 | ADC2_CH4, HSPI_MOSI |
| 15 | GPIO9 (SD2) | onboard flash |
| 16 | GPIO10 (SD3) | onboard flash |
| 17 | GPIO11 (CMD) | onboard flash |
| 18 | VIN | 5V power in |
| 19 | 3V3 | 3.3V power out |
| 20 | GND | Ground |
| 21 | GPIO23 | VSPI_MOSI |
| 22 | GPIO22 | I2C SCL |
| 23 | GPIO1 (TX0) | UART0 TX |
| 24 | GPIO3 (RX0) | UART0 RX |
| 25 | GPIO21 | I2C SDA |
| 26 | GND | Ground |
| 27 | GPIO19 | VSPI_MISO |
| 28 | GPIO18 | VSPI_CLK |
| 29 | GPIO5 | VSPI_CS0 |
| 30 | GPIO17 (TX2) | UART2 TX |
| 31 | GPIO16 (RX2) | UART2 RX |
| 32 | GPIO4 | ADC2_CH0 |
| 33 | GPIO0 | Boot mode select |
| 34 | GPIO2 | Onboard LED |
| 35 | GPIO15 | ADC2_CH3 |
| 36 | GPIO8 (SD1) | onboard flash |
| 37 | GPIO7 (SD0) | onboard flash |
| 38 | GPIO6 (CLK) | onboard flash |
Summary
Common ESP32-WROOM-32 38-pin DevKit V1 layout. Dual-core Wi-Fi + Bluetooth microcontroller module, the most popular ESP32 dev board for hobby projects. Has 38 GPIO pins covering ADC, I2C, SPI, UART, and PWM, so it can replace an Arduino in most projects while adding built-in wireless.
- CPU: Dual-core Xtensa LX6, up to 240MHz
- Wireless: Wi-Fi 802.11 b/g/n, Bluetooth 4.2 (BR/EDR + BLE)
- Flash: 4MB (typical)
- Supply voltage: 5V via VIN, 3.3V logic level
- Package: 38-pin DevKit board