SHT31 Monitor - Wiring
The SHT31 communicates over I2C - four wires from the sensor to the ESP32.
Pin Connections
| SHT31 Pin | Freenove ESP32-S3 WROOM Pin | Notes |
|---|---|---|
| VCC | 3.3V | Do not use 5V |
| GND | GND | |
| SDA | GPIO11 | I2C data |
| SCL | GPIO12 | I2C clock |
| ADDR | Not connected | Leaves I2C address at default 0x44 |
Notes
- Use the 3.3V pin, not 5V - the SHT31 is a 3.3V device
- Leave the ADDR pin floating (unconnected) for default address
0x44 - Connect with jumper wires via pin headers - no soldering required
- The Freenove ESP32-S3 WROOM has two USB-C ports:
- USB port - used for flashing and serial monitor
- UART port - do not use for flashing, monitoring only
I2C Address
| ADDR pin | I2C Address |
|---|---|
| Floating / GND | 0x44 (default) |
| VCC | 0x45 |
The config uses 0x44. If you need to run two SHT31 sensors on the same bus, connect the second sensor’s ADDR pin to VCC and set address: 0x45 in the config.