Build
Use an ESP32-S3 Super Mini or Seeed Studio XIAO ESP32-S3 with a ZW101-style UART fingerprint sensor. Use 3.3 V power and logic.
Wire the sensor
| Sensor pin | Signal | ESP32-S3 | XIAO |
|---|---|---|---|
| 1 | VTouch | 3V3 | 3V3 |
| 2 | TouchOut | GPIO2 | D1 |
| 3 | VCC | 3V3 | 3V3 |
| 4 | TX | GPIO44 (RX) | D7 |
| 5 | RX | GPIO43 (TX) | D6 |
| 6 | GND | GND | GND |
The UART pair is crossed: sensor TX goes to board RX. Sensor RX goes to board TX.
Check continuity. Confirm that 3V3 and GND are not shorted before connecting USB.
Next: Flash factory firmware.